freebsd-skq/sys/kern/kern_sig.c

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/*-
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* Copyright (c) 1982, 1986, 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
*/
2003-06-11 00:56:59 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_compat.h"
#include "opt_kdtrace.h"
#include "opt_ktrace.h"
#include "opt_core.h"
#include "opt_procdesc.h"
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#include <sys/param.h>
#include <sys/systm.h>
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#include <sys/signalvar.h>
#include <sys/vnode.h>
#include <sys/acct.h>
#include <sys/capability.h>
2001-01-16 01:00:43 +00:00
#include <sys/condvar.h>
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#include <sys/event.h>
#include <sys/fcntl.h>
#include <sys/imgact.h>
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#include <sys/kernel.h>
#include <sys/ktr.h>
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#include <sys/ktrace.h>
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#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/procdesc.h>
#include <sys/posix4.h>
2003-05-05 21:26:25 +00:00
#include <sys/pioctl.h>
#include <sys/racct.h>
#include <sys/resourcevar.h>
#include <sys/sdt.h>
#include <sys/sbuf.h>
Switch the sleep/wakeup and condition variable implementations to use the sleep queue interface: - Sleep queues attempt to merge some of the benefits of both sleep queues and condition variables. Having sleep qeueus in a hash table avoids having to allocate a queue head for each wait channel. Thus, struct cv has shrunk down to just a single char * pointer now. However, the hash table does not hold threads directly, but queue heads. This means that once you have located a queue in the hash bucket, you no longer have to walk the rest of the hash chain looking for threads. Instead, you have a list of all the threads sleeping on that wait channel. - Outside of the sleepq code and the sleep/cv code the kernel no longer differentiates between cv's and sleep/wakeup. For example, calls to abortsleep() and cv_abort() are replaced with a call to sleepq_abort(). Thus, the TDF_CVWAITQ flag is removed. Also, calls to unsleep() and cv_waitq_remove() have been replaced with calls to sleepq_remove(). - The sched_sleep() function no longer accepts a priority argument as sleep's no longer inherently bump the priority. Instead, this is soley a propery of msleep() which explicitly calls sched_prio() before blocking. - The TDF_ONSLEEPQ flag has been dropped as it was never used. The associated TDF_SET_ONSLEEPQ and TDF_CLR_ON_SLEEPQ macros have also been dropped and replaced with a single explicit clearing of td_wchan. TD_SET_ONSLEEPQ() would really have only made sense if it had taken the wait channel and message as arguments anyway. Now that that only happens in one place, a macro would be overkill.
2004-02-27 18:52:44 +00:00
#include <sys/sleepqueue.h>
Overhaul of the SMP code. Several portions of the SMP kernel support have been made machine independent and various other adjustments have been made to support Alpha SMP. - It splits the per-process portions of hardclock() and statclock() off into hardclock_process() and statclock_process() respectively. hardclock() and statclock() call the *_process() functions for the current process so that UP systems will run as before. For SMP systems, it is simply necessary to ensure that all other processors execute the *_process() functions when the main clock functions are triggered on one CPU by an interrupt. For the alpha 4100, clock interrupts are delievered in a staggered broadcast fashion, so we simply call hardclock/statclock on the boot CPU and call the *_process() functions on the secondaries. For x86, we call statclock and hardclock as usual and then call forward_hardclock/statclock in the MD code to send an IPI to cause the AP's to execute forwared_hardclock/statclock which then call the *_process() functions. - forward_signal() and forward_roundrobin() have been reworked to be MI and to involve less hackery. Now the cpu doing the forward sets any flags, etc. and sends a very simple IPI_AST to the other cpu(s). AST IPIs now just basically return so that they can execute ast() and don't bother with setting the astpending or needresched flags themselves. This also removes the loop in forward_signal() as sched_lock closes the race condition that the loop worked around. - need_resched(), resched_wanted() and clear_resched() have been changed to take a process to act on rather than assuming curproc so that they can be used to implement forward_roundrobin() as described above. - Various other SMP variables have been moved to a MI subr_smp.c and a new header sys/smp.h declares MI SMP variables and API's. The IPI API's from machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h. - The globaldata_register() and globaldata_find() functions as well as the SLIST of globaldata structures has become MI and moved into subr_smp.c. Also, the globaldata list is only available if SMP support is compiled in. Reviewed by: jake, peter Looked over by: eivind
2001-04-27 19:28:25 +00:00
#include <sys/smp.h>
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#include <sys/stat.h>
#include <sys/sx.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
2003-05-05 21:26:25 +00:00
#include <sys/sysent.h>
#include <sys/syslog.h>
#include <sys/sysproto.h>
#include <sys/timers.h>
#include <sys/unistd.h>
2003-05-05 21:26:25 +00:00
#include <sys/wait.h>
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/uma.h>
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#include <sys/jail.h>
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#include <machine/cpu.h>
#include <security/audit/audit.h>
#define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
SDT_PROVIDER_DECLARE(proc);
SDT_PROBE_DEFINE(proc, kernel, , signal_send, signal-send);
SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 0, "struct thread *");
SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 1, "struct proc *");
SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 2, "int");
SDT_PROBE_DEFINE(proc, kernel, , signal_clear, signal-clear);
SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 0, "int");
SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 1, "ksiginfo_t *");
SDT_PROBE_DEFINE(proc, kernel, , signal_discard, signal-discard);
SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 0, "struct thread *");
SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 1, "struct proc *");
SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 2, "int");
static int coredump(struct thread *);
static char *expand_name(const char *, uid_t, pid_t, struct thread *, int);
static int killpg1(struct thread *td, int sig, int pgid, int all,
ksiginfo_t *ksi);
static int issignal(struct thread *td, int stop_allowed);
static int sigprop(int sig);
static void tdsigwakeup(struct thread *, int, sig_t, int);
static void sig_suspend_threads(struct thread *, struct proc *, int);
static int filt_sigattach(struct knote *kn);
static void filt_sigdetach(struct knote *kn);
static int filt_signal(struct knote *kn, long hint);
static struct thread *sigtd(struct proc *p, int sig, int prop);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
static void sigqueue_start(void);
static uma_zone_t ksiginfo_zone = NULL;
struct filterops sig_filtops = {
.f_isfd = 0,
.f_attach = filt_sigattach,
.f_detach = filt_sigdetach,
.f_event = filt_signal,
};
static int kern_logsigexit = 1;
SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
&kern_logsigexit, 0,
"Log processes quitting on abnormal signals to syslog(3)");
static int kern_forcesigexit = 1;
SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
&kern_forcesigexit, 0, "Force trap signal to be handled");
static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
"POSIX real time signal");
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
static int max_pending_per_proc = 128;
SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
&max_pending_per_proc, 0, "Max pending signals per proc");
static int preallocate_siginfo = 1024;
TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
&preallocate_siginfo, 0, "Preallocated signal memory size");
static int signal_overflow = 0;
2005-12-09 02:26:44 +00:00
SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
&signal_overflow, 0, "Number of signals overflew");
static int signal_alloc_fail = 0;
2005-12-09 02:26:44 +00:00
SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
&signal_alloc_fail, 0, "signals failed to be allocated");
SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
/*
* Policy -- Can ucred cr1 send SIGIO to process cr2?
* Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
* in the right situations.
*/
#define CANSIGIO(cr1, cr2) \
((cr1)->cr_uid == 0 || \
(cr1)->cr_ruid == (cr2)->cr_ruid || \
(cr1)->cr_uid == (cr2)->cr_ruid || \
(cr1)->cr_ruid == (cr2)->cr_uid || \
(cr1)->cr_uid == (cr2)->cr_uid)
static int sugid_coredump;
SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
&sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
static int do_coredump = 1;
SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
&do_coredump, 0, "Enable/Disable coredumps");
static int set_core_nodump_flag = 0;
SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
0, "Enable setting the NODUMP flag on coredump files");
/*
* Signal properties and actions.
* The array below categorizes the signals and their default actions
* according to the following properties:
*/
#define SA_KILL 0x01 /* terminates process by default */
#define SA_CORE 0x02 /* ditto and coredumps */
#define SA_STOP 0x04 /* suspend process */
#define SA_TTYSTOP 0x08 /* ditto, from tty */
#define SA_IGNORE 0x10 /* ignore by default */
#define SA_CONT 0x20 /* continue if suspended */
#define SA_CANTMASK 0x40 /* non-maskable, catchable */
static int sigproptbl[NSIG] = {
SA_KILL, /* SIGHUP */
SA_KILL, /* SIGINT */
SA_KILL|SA_CORE, /* SIGQUIT */
SA_KILL|SA_CORE, /* SIGILL */
SA_KILL|SA_CORE, /* SIGTRAP */
SA_KILL|SA_CORE, /* SIGABRT */
SA_KILL|SA_CORE, /* SIGEMT */
SA_KILL|SA_CORE, /* SIGFPE */
SA_KILL, /* SIGKILL */
SA_KILL|SA_CORE, /* SIGBUS */
SA_KILL|SA_CORE, /* SIGSEGV */
SA_KILL|SA_CORE, /* SIGSYS */
SA_KILL, /* SIGPIPE */
SA_KILL, /* SIGALRM */
SA_KILL, /* SIGTERM */
SA_IGNORE, /* SIGURG */
SA_STOP, /* SIGSTOP */
SA_STOP|SA_TTYSTOP, /* SIGTSTP */
SA_IGNORE|SA_CONT, /* SIGCONT */
SA_IGNORE, /* SIGCHLD */
SA_STOP|SA_TTYSTOP, /* SIGTTIN */
SA_STOP|SA_TTYSTOP, /* SIGTTOU */
SA_IGNORE, /* SIGIO */
SA_KILL, /* SIGXCPU */
SA_KILL, /* SIGXFSZ */
SA_KILL, /* SIGVTALRM */
SA_KILL, /* SIGPROF */
SA_IGNORE, /* SIGWINCH */
SA_IGNORE, /* SIGINFO */
SA_KILL, /* SIGUSR1 */
SA_KILL, /* SIGUSR2 */
};
static void reschedule_signals(struct proc *p, sigset_t block, int flags);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
static void
sigqueue_start(void)
{
ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
uma_prealloc(ksiginfo_zone, preallocate_siginfo);
2005-12-01 00:25:50 +00:00
p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
}
ksiginfo_t *
ksiginfo_alloc(int wait)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
{
int flags;
flags = M_ZERO;
if (! wait)
flags |= M_NOWAIT;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (ksiginfo_zone != NULL)
return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
return (NULL);
}
void
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksiginfo_free(ksiginfo_t *ksi)
{
uma_zfree(ksiginfo_zone, ksi);
}
static __inline int
ksiginfo_tryfree(ksiginfo_t *ksi)
{
if (!(ksi->ksi_flags & KSI_EXT)) {
uma_zfree(ksiginfo_zone, ksi);
return (1);
}
return (0);
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
void
sigqueue_init(sigqueue_t *list, struct proc *p)
{
SIGEMPTYSET(list->sq_signals);
SIGEMPTYSET(list->sq_kill);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
TAILQ_INIT(&list->sq_list);
list->sq_proc = p;
list->sq_flags = SQ_INIT;
}
/*
* Get a signal's ksiginfo.
* Return:
* 0 - signal not found
* others - signal number
*/
static int
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
{
struct proc *p = sq->sq_proc;
struct ksiginfo *ksi, *next;
int count = 0;
KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
if (!SIGISMEMBER(sq->sq_signals, signo))
return (0);
if (SIGISMEMBER(sq->sq_kill, signo)) {
count++;
SIGDELSET(sq->sq_kill, signo);
}
TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (ksi->ksi_signo == signo) {
if (count == 0) {
TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
ksi->ksi_sigq = NULL;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksiginfo_copy(ksi, si);
if (ksiginfo_tryfree(ksi) && p != NULL)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
p->p_pendingcnt--;
}
if (++count > 1)
break;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
}
}
if (count <= 1)
SIGDELSET(sq->sq_signals, signo);
si->ksi_signo = signo;
return (signo);
}
void
sigqueue_take(ksiginfo_t *ksi)
{
struct ksiginfo *kp;
struct proc *p;
sigqueue_t *sq;
if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
return;
p = sq->sq_proc;
TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
ksi->ksi_sigq = NULL;
if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
p->p_pendingcnt--;
for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
kp = TAILQ_NEXT(kp, ksi_link)) {
if (kp->ksi_signo == ksi->ksi_signo)
break;
}
if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
SIGDELSET(sq->sq_signals, ksi->ksi_signo);
}
static int
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
{
struct proc *p = sq->sq_proc;
struct ksiginfo *ksi;
int ret = 0;
KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
SIGADDSET(sq->sq_kill, signo);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
goto out_set_bit;
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
/* directly insert the ksi, don't copy it */
if (si->ksi_flags & KSI_INS) {
if (si->ksi_flags & KSI_HEAD)
TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
else
TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
si->ksi_sigq = sq;
goto out_set_bit;
}
if (__predict_false(ksiginfo_zone == NULL)) {
SIGADDSET(sq->sq_kill, signo);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
goto out_set_bit;
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
signal_overflow++;
ret = EAGAIN;
} else if ((ksi = ksiginfo_alloc(0)) == NULL) {
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
signal_alloc_fail++;
ret = EAGAIN;
} else {
if (p != NULL)
p->p_pendingcnt++;
ksiginfo_copy(si, ksi);
ksi->ksi_signo = signo;
if (si->ksi_flags & KSI_HEAD)
TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
else
TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
ksi->ksi_sigq = sq;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
}
if ((si->ksi_flags & KSI_TRAP) != 0 ||
(si->ksi_flags & KSI_SIGQ) == 0) {
if (ret != 0)
SIGADDSET(sq->sq_kill, signo);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ret = 0;
goto out_set_bit;
}
if (ret != 0)
return (ret);
out_set_bit:
SIGADDSET(sq->sq_signals, signo);
return (ret);
}
void
sigqueue_flush(sigqueue_t *sq)
{
struct proc *p = sq->sq_proc;
ksiginfo_t *ksi;
KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
if (p != NULL)
PROC_LOCK_ASSERT(p, MA_OWNED);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
ksi->ksi_sigq = NULL;
if (ksiginfo_tryfree(ksi) && p != NULL)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
p->p_pendingcnt--;
}
SIGEMPTYSET(sq->sq_signals);
SIGEMPTYSET(sq->sq_kill);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
}
static void
sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
{
sigset_t tmp;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
struct proc *p1, *p2;
ksiginfo_t *ksi, *next;
KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
p1 = src->sq_proc;
p2 = dst->sq_proc;
/* Move siginfo to target list */
TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
if (SIGISMEMBER(*set, ksi->ksi_signo)) {
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
if (p1 != NULL)
p1->p_pendingcnt--;
TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
ksi->ksi_sigq = dst;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (p2 != NULL)
p2->p_pendingcnt++;
}
}
/* Move pending bits to target list */
tmp = src->sq_kill;
SIGSETAND(tmp, *set);
SIGSETOR(dst->sq_kill, tmp);
SIGSETNAND(src->sq_kill, tmp);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
tmp = src->sq_signals;
SIGSETAND(tmp, *set);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
SIGSETOR(dst->sq_signals, tmp);
SIGSETNAND(src->sq_signals, tmp);
}
#if 0
static void
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
{
sigset_t set;
SIGEMPTYSET(set);
SIGADDSET(set, signo);
sigqueue_move_set(src, dst, &set);
}
#endif
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
static void
sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
{
struct proc *p = sq->sq_proc;
ksiginfo_t *ksi, *next;
KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
/* Remove siginfo queue */
TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (SIGISMEMBER(*set, ksi->ksi_signo)) {
TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
ksi->ksi_sigq = NULL;
if (ksiginfo_tryfree(ksi) && p != NULL)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
p->p_pendingcnt--;
}
}
SIGSETNAND(sq->sq_kill, *set);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
SIGSETNAND(sq->sq_signals, *set);
}
void
sigqueue_delete(sigqueue_t *sq, int signo)
{
sigset_t set;
SIGEMPTYSET(set);
SIGADDSET(set, signo);
sigqueue_delete_set(sq, &set);
}
/* Remove a set of signals for a process */
static void
sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
{
sigqueue_t worklist;
struct thread *td0;
PROC_LOCK_ASSERT(p, MA_OWNED);
sigqueue_init(&worklist, NULL);
sigqueue_move_set(&p->p_sigqueue, &worklist, set);
FOREACH_THREAD_IN_PROC(p, td0)
sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
sigqueue_flush(&worklist);
}
void
sigqueue_delete_proc(struct proc *p, int signo)
{
sigset_t set;
SIGEMPTYSET(set);
SIGADDSET(set, signo);
sigqueue_delete_set_proc(p, &set);
}
static void
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete_stopmask_proc(struct proc *p)
{
sigset_t set;
SIGEMPTYSET(set);
SIGADDSET(set, SIGSTOP);
SIGADDSET(set, SIGTSTP);
SIGADDSET(set, SIGTTIN);
SIGADDSET(set, SIGTTOU);
sigqueue_delete_set_proc(p, &set);
}
/*
* Determine signal that should be delivered to process p, the current
* process, 0 if none. If there is a pending stop signal with default
* action, the process stops in issignal().
*/
int
cursig(struct thread *td, int stop_allowed)
{
PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
KASSERT(stop_allowed == SIG_STOP_ALLOWED ||
stop_allowed == SIG_STOP_NOT_ALLOWED, ("cursig: stop_allowed"));
mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
return (SIGPENDING(td) ? issignal(td, stop_allowed) : 0);
}
/*
* Arrange for ast() to handle unmasked pending signals on return to user
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
* mode. This must be called whenever a signal is added to td_sigqueue or
* unmasked in td_sigmask.
*/
void
signotify(struct thread *td)
{
struct proc *p;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
if (SIGPENDING(td)) {
thread_lock(td);
td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
thread_unlock(td);
}
}
int
sigonstack(size_t sp)
{
struct thread *td = curthread;
return ((td->td_pflags & TDP_ALTSTACK) ?
#if defined(COMPAT_43)
((td->td_sigstk.ss_size == 0) ?
(td->td_sigstk.ss_flags & SS_ONSTACK) :
((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
#else
((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
#endif
: 0);
}
static __inline int
sigprop(int sig)
{
if (sig > 0 && sig < NSIG)
return (sigproptbl[_SIG_IDX(sig)]);
return (0);
}
int
sig_ffs(sigset_t *set)
{
int i;
for (i = 0; i < _SIG_WORDS; i++)
if (set->__bits[i])
return (ffs(set->__bits[i]) + (i * 32));
return (0);
}
/*
* kern_sigaction
* sigaction
* freebsd4_sigaction
* osigaction
*/
int
kern_sigaction(td, sig, act, oact, flags)
struct thread *td;
register int sig;
struct sigaction *act, *oact;
int flags;
{
struct sigacts *ps;
struct proc *p = td->td_proc;
if (!_SIG_VALID(sig))
return (EINVAL);
PROC_LOCK(p);
ps = p->p_sigacts;
mtx_lock(&ps->ps_mtx);
if (oact) {
oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
oact->sa_flags = 0;
if (SIGISMEMBER(ps->ps_sigonstack, sig))
oact->sa_flags |= SA_ONSTACK;
if (!SIGISMEMBER(ps->ps_sigintr, sig))
oact->sa_flags |= SA_RESTART;
if (SIGISMEMBER(ps->ps_sigreset, sig))
oact->sa_flags |= SA_RESETHAND;
if (SIGISMEMBER(ps->ps_signodefer, sig))
oact->sa_flags |= SA_NODEFER;
if (SIGISMEMBER(ps->ps_siginfo, sig)) {
oact->sa_flags |= SA_SIGINFO;
oact->sa_sigaction =
(__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
} else
oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
oact->sa_flags |= SA_NOCLDSTOP;
if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
oact->sa_flags |= SA_NOCLDWAIT;
}
if (act) {
if ((sig == SIGKILL || sig == SIGSTOP) &&
act->sa_handler != SIG_DFL) {
mtx_unlock(&ps->ps_mtx);
PROC_UNLOCK(p);
return (EINVAL);
}
/*
* Change setting atomically.
*/
ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
if (act->sa_flags & SA_SIGINFO) {
ps->ps_sigact[_SIG_IDX(sig)] =
(__sighandler_t *)act->sa_sigaction;
SIGADDSET(ps->ps_siginfo, sig);
} else {
ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
SIGDELSET(ps->ps_siginfo, sig);
}
if (!(act->sa_flags & SA_RESTART))
SIGADDSET(ps->ps_sigintr, sig);
else
SIGDELSET(ps->ps_sigintr, sig);
if (act->sa_flags & SA_ONSTACK)
SIGADDSET(ps->ps_sigonstack, sig);
else
SIGDELSET(ps->ps_sigonstack, sig);
if (act->sa_flags & SA_RESETHAND)
SIGADDSET(ps->ps_sigreset, sig);
else
SIGDELSET(ps->ps_sigreset, sig);
if (act->sa_flags & SA_NODEFER)
SIGADDSET(ps->ps_signodefer, sig);
else
SIGDELSET(ps->ps_signodefer, sig);
if (sig == SIGCHLD) {
if (act->sa_flags & SA_NOCLDSTOP)
ps->ps_flag |= PS_NOCLDSTOP;
else
ps->ps_flag &= ~PS_NOCLDSTOP;
if (act->sa_flags & SA_NOCLDWAIT) {
/*
* Paranoia: since SA_NOCLDWAIT is implemented
* by reparenting the dying child to PID 1 (and
* trust it to reap the zombie), PID 1 itself
* is forbidden to set SA_NOCLDWAIT.
*/
if (p->p_pid == 1)
ps->ps_flag &= ~PS_NOCLDWAIT;
else
ps->ps_flag |= PS_NOCLDWAIT;
} else
ps->ps_flag &= ~PS_NOCLDWAIT;
if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
ps->ps_flag |= PS_CLDSIGIGN;
else
ps->ps_flag &= ~PS_CLDSIGIGN;
}
/*
* Set bit in ps_sigignore for signals that are set to SIG_IGN,
* and for signals set to SIG_DFL where the default is to
* ignore. However, don't put SIGCONT in ps_sigignore, as we
* have to restart the process.
*/
if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
(sigprop(sig) & SA_IGNORE &&
ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
/* never to be seen again */
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete_proc(p, sig);
if (sig != SIGCONT)
/* easier in psignal */
SIGADDSET(ps->ps_sigignore, sig);
SIGDELSET(ps->ps_sigcatch, sig);
} else {
SIGDELSET(ps->ps_sigignore, sig);
if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
SIGDELSET(ps->ps_sigcatch, sig);
else
SIGADDSET(ps->ps_sigcatch, sig);
}
#ifdef COMPAT_FREEBSD4
if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
(flags & KSA_FREEBSD4) == 0)
SIGDELSET(ps->ps_freebsd4, sig);
else
SIGADDSET(ps->ps_freebsd4, sig);
#endif
#ifdef COMPAT_43
if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
(flags & KSA_OSIGSET) == 0)
SIGDELSET(ps->ps_osigset, sig);
else
SIGADDSET(ps->ps_osigset, sig);
#endif
}
mtx_unlock(&ps->ps_mtx);
PROC_UNLOCK(p);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct sigaction_args {
int sig;
struct sigaction *act;
struct sigaction *oact;
1994-05-24 10:09:53 +00:00
};
#endif
int
sys_sigaction(td, uap)
struct thread *td;
1994-05-24 10:09:53 +00:00
register struct sigaction_args *uap;
{
struct sigaction act, oact;
register struct sigaction *actp, *oactp;
int error;
1994-05-24 10:09:53 +00:00
actp = (uap->act != NULL) ? &act : NULL;
oactp = (uap->oact != NULL) ? &oact : NULL;
if (actp) {
error = copyin(uap->act, actp, sizeof(act));
if (error)
return (error);
1994-05-24 10:09:53 +00:00
}
error = kern_sigaction(td, uap->sig, actp, oactp, 0);
if (oactp && !error)
error = copyout(oactp, uap->oact, sizeof(oact));
return (error);
1994-05-24 10:09:53 +00:00
}
#ifdef COMPAT_FREEBSD4
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_sigaction_args {
int sig;
struct sigaction *act;
struct sigaction *oact;
};
#endif
int
freebsd4_sigaction(td, uap)
struct thread *td;
register struct freebsd4_sigaction_args *uap;
{
struct sigaction act, oact;
register struct sigaction *actp, *oactp;
int error;
actp = (uap->act != NULL) ? &act : NULL;
oactp = (uap->oact != NULL) ? &oact : NULL;
if (actp) {
error = copyin(uap->act, actp, sizeof(act));
if (error)
return (error);
}
error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
if (oactp && !error)
error = copyout(oactp, uap->oact, sizeof(oact));
return (error);
}
#endif /* COMAPT_FREEBSD4 */
#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
#ifndef _SYS_SYSPROTO_H_
struct osigaction_args {
int signum;
struct osigaction *nsa;
struct osigaction *osa;
};
#endif
int
osigaction(td, uap)
struct thread *td;
register struct osigaction_args *uap;
1994-05-24 10:09:53 +00:00
{
struct osigaction sa;
struct sigaction nsa, osa;
register struct sigaction *nsap, *osap;
int error;
1994-05-24 10:09:53 +00:00
if (uap->signum <= 0 || uap->signum >= ONSIG)
return (EINVAL);
nsap = (uap->nsa != NULL) ? &nsa : NULL;
osap = (uap->osa != NULL) ? &osa : NULL;
if (nsap) {
error = copyin(uap->nsa, &sa, sizeof(sa));
if (error)
return (error);
nsap->sa_handler = sa.sa_handler;
nsap->sa_flags = sa.sa_flags;
OSIG2SIG(sa.sa_mask, nsap->sa_mask);
Implement SA_SIGINFO for i386. Thanks to Bruce Evans for much more than a review, this was a nice puzzle. This is supposed to be binary and source compatible with older applications that access the old FreeBSD-style three arguments to a signal handler. Except those applications that access hidden signal handler arguments bejond the documented third one. If you have applications that do, please let me know so that we take the opportunity to provide the functionality they need in a documented manner. Also except application that use 'struct sigframe' directly. You need to recompile gdb and doscmd. `make world` is recommended. Example program that demonstrates how SA_SIGINFO and old-style FreeBSD handlers (with their three args) may be used in the same process is at http://www3.cons.org/tmp/fbsd-siginfo.c Programs that use the old FreeBSD-style three arguments are easy to change to SA_SIGINFO (although they don't need to, since the old style will still work): Old args to signal handler: void handler_sn(int sig, int code, struct sigcontext *scp) New args: void handler_si(int sig, siginfo_t *si, void *third) where: old:code == new:second->si_code old:scp == &(new:si->si_scp) /* Passed by value! */ The latter is also pointed to by new:third, but accessing via si->si_scp is preferred because it is type-save. FreeBSD implementation notes: - This is just the framework to make the interface POSIX compatible. For now, no additional functionality is provided. This is supposed to happen now, starting with floating point values. - We don't use 'sigcontext_t.si_value' for now (POSIX meant it for realtime-related values). - Documentation will be updated when new functionality is added and the exact arguments passed are determined. The comments in sys/signal.h are meant to be useful. Reviewed by: BDE
1999-07-06 07:13:48 +00:00
}
error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
if (osap && !error) {
sa.sa_handler = osap->sa_handler;
sa.sa_flags = osap->sa_flags;
SIG2OSIG(osap->sa_mask, sa.sa_mask);
error = copyout(&sa, uap->osa, sizeof(sa));
1994-05-24 10:09:53 +00:00
}
return (error);
1994-05-24 10:09:53 +00:00
}
#if !defined(__i386__)
/* Avoid replicating the same stub everywhere */
int
osigreturn(td, uap)
struct thread *td;
struct osigreturn_args *uap;
{
return (nosys(td, (struct nosys_args *)uap));
}
#endif
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
/*
* Initialize signal state for process 0;
* set to ignore signals that are ignored by default.
*/
void
siginit(p)
struct proc *p;
{
register int i;
struct sigacts *ps;
1994-05-24 10:09:53 +00:00
PROC_LOCK(p);
ps = p->p_sigacts;
mtx_lock(&ps->ps_mtx);
for (i = 1; i <= NSIG; i++)
if (sigprop(i) & SA_IGNORE && i != SIGCONT)
SIGADDSET(ps->ps_sigignore, i);
mtx_unlock(&ps->ps_mtx);
PROC_UNLOCK(p);
1994-05-24 10:09:53 +00:00
}
/*
* Reset signals for an exec of the specified process.
*/
void
execsigs(struct proc *p)
1994-05-24 10:09:53 +00:00
{
struct sigacts *ps;
int sig;
struct thread *td;
1994-05-24 10:09:53 +00:00
/*
* Reset caught signals. Held signals remain held
* through td_sigmask (unless they were caught,
1994-05-24 10:09:53 +00:00
* and are now ignored by default).
*/
PROC_LOCK_ASSERT(p, MA_OWNED);
td = FIRST_THREAD_IN_PROC(p);
ps = p->p_sigacts;
mtx_lock(&ps->ps_mtx);
while (SIGNOTEMPTY(ps->ps_sigcatch)) {
sig = sig_ffs(&ps->ps_sigcatch);
SIGDELSET(ps->ps_sigcatch, sig);
if (sigprop(sig) & SA_IGNORE) {
if (sig != SIGCONT)
SIGADDSET(ps->ps_sigignore, sig);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete_proc(p, sig);
1994-05-24 10:09:53 +00:00
}
ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1994-05-24 10:09:53 +00:00
}
/*
* Reset stack state to the user stack.
* Clear set of signals caught on the signal stack.
*/
td->td_sigstk.ss_flags = SS_DISABLE;
td->td_sigstk.ss_size = 0;
td->td_sigstk.ss_sp = 0;
td->td_pflags &= ~TDP_ALTSTACK;
/*
* Reset no zombies if child dies flag as Solaris does.
*/
ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
mtx_unlock(&ps->ps_mtx);
1994-05-24 10:09:53 +00:00
}
/*
* kern_sigprocmask()
*
* Manipulate signal mask.
1994-05-24 10:09:53 +00:00
*/
int
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
int flags)
{
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
sigset_t new_block, oset1;
struct proc *p;
int error;
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
p = td->td_proc;
if (!(flags & SIGPROCMASK_PROC_LOCKED))
PROC_LOCK(p);
if (oset != NULL)
*oset = td->td_sigmask;
error = 0;
if (set != NULL) {
switch (how) {
case SIG_BLOCK:
SIG_CANTMASK(*set);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
oset1 = td->td_sigmask;
SIGSETOR(td->td_sigmask, *set);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
new_block = td->td_sigmask;
SIGSETNAND(new_block, oset1);
break;
case SIG_UNBLOCK:
SIGSETNAND(td->td_sigmask, *set);
signotify(td);
goto out;
case SIG_SETMASK:
SIG_CANTMASK(*set);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
oset1 = td->td_sigmask;
if (flags & SIGPROCMASK_OLD)
SIGSETLO(td->td_sigmask, *set);
else
td->td_sigmask = *set;
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
new_block = td->td_sigmask;
SIGSETNAND(new_block, oset1);
signotify(td);
break;
default:
error = EINVAL;
goto out;
}
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
/*
* The new_block set contains signals that were not previously
* blocked, but are blocked now.
*
* In case we block any signal that was not previously blocked
* for td, and process has the signal pending, try to schedule
* signal delivery to some thread that does not block the
* signal, possibly waking it up.
*/
if (p->p_numthreads != 1)
reschedule_signals(p, new_block, flags);
}
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
out:
if (!(flags & SIGPROCMASK_PROC_LOCKED))
PROC_UNLOCK(p);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct sigprocmask_args {
int how;
const sigset_t *set;
sigset_t *oset;
1994-05-24 10:09:53 +00:00
};
#endif
int
sys_sigprocmask(td, uap)
register struct thread *td;
1994-05-24 10:09:53 +00:00
struct sigprocmask_args *uap;
{
sigset_t set, oset;
sigset_t *setp, *osetp;
int error;
1994-05-24 10:09:53 +00:00
setp = (uap->set != NULL) ? &set : NULL;
osetp = (uap->oset != NULL) ? &oset : NULL;
if (setp) {
error = copyin(uap->set, setp, sizeof(set));
if (error)
return (error);
}
error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
if (osetp && !error) {
error = copyout(osetp, uap->oset, sizeof(oset));
}
return (error);
}
1994-05-24 10:09:53 +00:00
#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
#ifndef _SYS_SYSPROTO_H_
struct osigprocmask_args {
int how;
osigset_t mask;
};
#endif
int
osigprocmask(td, uap)
register struct thread *td;
struct osigprocmask_args *uap;
{
sigset_t set, oset;
int error;
1995-05-30 08:16:23 +00:00
OSIG2SIG(uap->mask, set);
error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
SIG2OSIG(oset, td->td_retval[0]);
1994-05-24 10:09:53 +00:00
return (error);
}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
int
sys_sigwait(struct thread *td, struct sigwait_args *uap)
{
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksiginfo_t ksi;
sigset_t set;
int error;
error = copyin(uap->set, &set, sizeof(set));
if (error) {
td->td_retval[0] = error;
return (0);
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
error = kern_sigtimedwait(td, set, &ksi, NULL);
if (error) {
if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
error = ERESTART;
if (error == ERESTART)
return (error);
td->td_retval[0] = error;
return (0);
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
td->td_retval[0] = error;
return (0);
}
int
sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
{
struct timespec ts;
struct timespec *timeout;
sigset_t set;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksiginfo_t ksi;
int error;
if (uap->timeout) {
error = copyin(uap->timeout, &ts, sizeof(ts));
if (error)
return (error);
timeout = &ts;
} else
timeout = NULL;
error = copyin(uap->set, &set, sizeof(set));
if (error)
return (error);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
error = kern_sigtimedwait(td, set, &ksi, timeout);
if (error)
return (error);
if (uap->info)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
if (error == 0)
td->td_retval[0] = ksi.ksi_signo;
return (error);
}
int
sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
{
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksiginfo_t ksi;
sigset_t set;
int error;
error = copyin(uap->set, &set, sizeof(set));
if (error)
return (error);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
error = kern_sigtimedwait(td, set, &ksi, NULL);
if (error)
return (error);
if (uap->info)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
if (error == 0)
td->td_retval[0] = ksi.ksi_signo;
return (error);
}
int
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
struct timespec *timeout)
{
struct sigacts *ps;
sigset_t saved_mask, new_block;
struct proc *p;
int error, sig, timo, timevalid = 0;
struct timespec rts, ets, ts;
struct timeval tv;
p = td->td_proc;
error = 0;
ets.tv_sec = 0;
ets.tv_nsec = 0;
if (timeout != NULL) {
if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
timevalid = 1;
getnanouptime(&rts);
ets = rts;
timespecadd(&ets, timeout);
}
}
ksiginfo_init(ksi);
/* Some signals can not be waited for. */
SIG_CANTMASK(waitset);
ps = p->p_sigacts;
PROC_LOCK(p);
saved_mask = td->td_sigmask;
SIGSETNAND(td->td_sigmask, waitset);
for (;;) {
mtx_lock(&ps->ps_mtx);
sig = cursig(td, SIG_STOP_ALLOWED);
mtx_unlock(&ps->ps_mtx);
if (sig != 0 && SIGISMEMBER(waitset, sig)) {
if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
error = 0;
break;
}
}
if (error != 0)
break;
/*
* POSIX says this must be checked after looking for pending
* signals.
*/
if (timeout != NULL) {
if (!timevalid) {
error = EINVAL;
break;
}
getnanouptime(&rts);
if (timespeccmp(&rts, &ets, >=)) {
error = EAGAIN;
break;
}
ts = ets;
timespecsub(&ts, &rts);
TIMESPEC_TO_TIMEVAL(&tv, &ts);
timo = tvtohz(&tv);
} else {
timo = 0;
}
error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
if (timeout != NULL) {
if (error == ERESTART) {
/* Timeout can not be restarted. */
error = EINTR;
} else if (error == EAGAIN) {
/* We will calculate timeout by ourself. */
error = 0;
}
}
}
new_block = saved_mask;
SIGSETNAND(new_block, td->td_sigmask);
td->td_sigmask = saved_mask;
/*
* Fewer signals can be delivered to us, reschedule signal
* notification.
*/
if (p->p_numthreads != 1)
reschedule_signals(p, new_block, 0);
if (error == 0) {
SDT_PROBE(proc, kernel, , signal_clear, sig, ksi, 0, 0, 0);
if (ksi->ksi_code == SI_TIMER)
itimer_accept(p, ksi->ksi_timerid, ksi);
#ifdef KTRACE
if (KTRPOINT(td, KTR_PSIG)) {
sig_t action;
mtx_lock(&ps->ps_mtx);
action = ps->ps_sigact[_SIG_IDX(sig)];
mtx_unlock(&ps->ps_mtx);
ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
}
#endif
if (sig == SIGKILL)
sigexit(td, sig);
}
PROC_UNLOCK(p);
return (error);
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
#ifndef _SYS_SYSPROTO_H_
struct sigpending_args {
sigset_t *set;
};
#endif
int
sys_sigpending(td, uap)
struct thread *td;
1994-05-24 10:09:53 +00:00
struct sigpending_args *uap;
{
struct proc *p = td->td_proc;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigset_t pending;
1994-05-24 10:09:53 +00:00
PROC_LOCK(p);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
pending = p->p_sigqueue.sq_signals;
SIGSETOR(pending, td->td_sigqueue.sq_signals);
PROC_UNLOCK(p);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
return (copyout(&pending, uap->set, sizeof(sigset_t)));
}
#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
#ifndef _SYS_SYSPROTO_H_
struct osigpending_args {
int dummy;
};
#endif
int
osigpending(td, uap)
struct thread *td;
struct osigpending_args *uap;
{
struct proc *p = td->td_proc;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigset_t pending;
PROC_LOCK(p);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
pending = p->p_sigqueue.sq_signals;
SIGSETOR(pending, td->td_sigqueue.sq_signals);
PROC_UNLOCK(p);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
SIG2OSIG(pending, td->td_retval[0]);
1994-05-24 10:09:53 +00:00
return (0);
}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
#if defined(COMPAT_43)
1994-05-24 10:09:53 +00:00
/*
* Generalized interface signal handler, 4.3-compatible.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct osigvec_args {
int signum;
struct sigvec *nsv;
struct sigvec *osv;
};
#endif
1994-05-24 10:09:53 +00:00
/* ARGSUSED */
int
osigvec(td, uap)
struct thread *td;
1994-05-24 10:09:53 +00:00
register struct osigvec_args *uap;
{
struct sigvec vec;
struct sigaction nsa, osa;
register struct sigaction *nsap, *osap;
int error;
1994-05-24 10:09:53 +00:00
if (uap->signum <= 0 || uap->signum >= ONSIG)
return (EINVAL);
nsap = (uap->nsv != NULL) ? &nsa : NULL;
osap = (uap->osv != NULL) ? &osa : NULL;
if (nsap) {
error = copyin(uap->nsv, &vec, sizeof(vec));
if (error)
1994-05-24 10:09:53 +00:00
return (error);
nsap->sa_handler = vec.sv_handler;
OSIG2SIG(vec.sv_mask, nsap->sa_mask);
nsap->sa_flags = vec.sv_flags;
nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1994-05-24 10:09:53 +00:00
}
error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
if (osap && !error) {
vec.sv_handler = osap->sa_handler;
SIG2OSIG(osap->sa_mask, vec.sv_mask);
vec.sv_flags = osap->sa_flags;
vec.sv_flags &= ~SA_NOCLDWAIT;
vec.sv_flags ^= SA_RESTART;
error = copyout(&vec, uap->osv, sizeof(vec));
1994-05-24 10:09:53 +00:00
}
return (error);
1994-05-24 10:09:53 +00:00
}
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct osigblock_args {
int mask;
};
#endif
int
osigblock(td, uap)
register struct thread *td;
1994-05-24 10:09:53 +00:00
struct osigblock_args *uap;
{
sigset_t set, oset;
1994-05-24 10:09:53 +00:00
OSIG2SIG(uap->mask, set);
kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
SIG2OSIG(oset, td->td_retval[0]);
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return (0);
}
#ifndef _SYS_SYSPROTO_H_
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struct osigsetmask_args {
int mask;
};
#endif
int
osigsetmask(td, uap)
struct thread *td;
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struct osigsetmask_args *uap;
{
sigset_t set, oset;
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OSIG2SIG(uap->mask, set);
kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
SIG2OSIG(oset, td->td_retval[0]);
1994-05-24 10:09:53 +00:00
return (0);
}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
/*
* Suspend calling thread until signal, providing mask to be set in the
* meantime.
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*/
#ifndef _SYS_SYSPROTO_H_
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struct sigsuspend_args {
const sigset_t *sigmask;
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};
#endif
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/* ARGSUSED */
int
sys_sigsuspend(td, uap)
struct thread *td;
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struct sigsuspend_args *uap;
{
sigset_t mask;
int error;
error = copyin(uap->sigmask, &mask, sizeof(mask));
if (error)
return (error);
return (kern_sigsuspend(td, mask));
}
int
kern_sigsuspend(struct thread *td, sigset_t mask)
{
struct proc *p = td->td_proc;
int has_sig, sig;
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/*
* When returning from sigsuspend, we want
1994-05-24 10:09:53 +00:00
* the old mask to be restored after the
* signal handler has finished. Thus, we
* save it here and mark the sigacts structure
* to indicate this.
*/
PROC_LOCK(p);
kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
SIGPROCMASK_PROC_LOCKED);
td->td_pflags |= TDP_OLDMASK;
/*
* Process signals now. Otherwise, we can get spurious wakeup
* due to signal entered process queue, but delivered to other
* thread. But sigsuspend should return only on signal
* delivery.
*/
Reorganize syscall entry and leave handling. Extend struct sysvec with three new elements: sv_fetch_syscall_args - the method to fetch syscall arguments from usermode into struct syscall_args. The structure is machine-depended (this might be reconsidered after all architectures are converted). sv_set_syscall_retval - the method to set a return value for usermode from the syscall. It is a generalization of cpu_set_syscall_retval(9) to allow ABIs to override the way to set a return value. sv_syscallnames - the table of syscall names. Use sv_set_syscall_retval in kern_sigsuspend() instead of hardcoding the call to cpu_set_syscall_retval(). The new functions syscallenter(9) and syscallret(9) are provided that use sv_*syscall* pointers and contain the common repeated code from the syscall() implementations for the architecture-specific syscall trap handlers. Syscallenter() fetches arguments, calls syscall implementation from ABI sysent table, and set up return frame. The end of syscall bookkeeping is done by syscallret(). Take advantage of single place for MI syscall handling code and implement ptrace_lwpinfo pl_flags PL_FLAG_SCE, PL_FLAG_SCX and PL_FLAG_EXEC. The SCE and SCX flags notify the debugger that the thread is stopped at syscall entry or return point respectively. The EXEC flag augments SCX and notifies debugger that the process address space was changed by one of exec(2)-family syscalls. The i386, amd64, sparc64, sun4v, powerpc and ia64 syscall()s are changed to use syscallenter()/syscallret(). MIPS and arm are not converted and use the mostly unchanged syscall() implementation. Reviewed by: jhb, marcel, marius, nwhitehorn, stas Tested by: marcel (ia64), marius (sparc64), nwhitehorn (powerpc), stas (mips) MFC after: 1 month
2010-05-23 18:32:02 +00:00
(p->p_sysent->sv_set_syscall_retval)(td, EINTR);
for (has_sig = 0; !has_sig;) {
while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
0) == 0)
/* void */;
thread_suspend_check(0);
mtx_lock(&p->p_sigacts->ps_mtx);
while ((sig = cursig(td, SIG_STOP_ALLOWED)) != 0)
has_sig += postsig(sig);
mtx_unlock(&p->p_sigacts->ps_mtx);
}
PROC_UNLOCK(p);
td->td_errno = EINTR;
td->td_pflags |= TDP_NERRNO;
return (EJUSTRETURN);
}
#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
/*
* Compatibility sigsuspend call for old binaries. Note nonstandard calling
* convention: libc stub passes mask, not pointer, to save a copyin.
*/
#ifndef _SYS_SYSPROTO_H_
struct osigsuspend_args {
osigset_t mask;
};
#endif
/* ARGSUSED */
int
osigsuspend(td, uap)
struct thread *td;
struct osigsuspend_args *uap;
{
sigset_t mask;
OSIG2SIG(uap->mask, mask);
return (kern_sigsuspend(td, mask));
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}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
#if defined(COMPAT_43)
#ifndef _SYS_SYSPROTO_H_
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struct osigstack_args {
struct sigstack *nss;
struct sigstack *oss;
};
#endif
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/* ARGSUSED */
int
osigstack(td, uap)
struct thread *td;
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register struct osigstack_args *uap;
{
struct sigstack nss, oss;
int error = 0;
if (uap->nss != NULL) {
error = copyin(uap->nss, &nss, sizeof(nss));
if (error)
return (error);
}
oss.ss_sp = td->td_sigstk.ss_sp;
oss.ss_onstack = sigonstack(cpu_getstack(td));
if (uap->nss != NULL) {
td->td_sigstk.ss_sp = nss.ss_sp;
td->td_sigstk.ss_size = 0;
td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
td->td_pflags |= TDP_ALTSTACK;
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}
if (uap->oss != NULL)
error = copyout(&oss, uap->oss, sizeof(oss));
return (error);
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}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
#ifndef _SYS_SYSPROTO_H_
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struct sigaltstack_args {
stack_t *ss;
stack_t *oss;
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};
#endif
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/* ARGSUSED */
int
sys_sigaltstack(td, uap)
struct thread *td;
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register struct sigaltstack_args *uap;
{
stack_t ss, oss;
int error;
if (uap->ss != NULL) {
error = copyin(uap->ss, &ss, sizeof(ss));
if (error)
return (error);
}
error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
(uap->oss != NULL) ? &oss : NULL);
if (error)
return (error);
if (uap->oss != NULL)
error = copyout(&oss, uap->oss, sizeof(stack_t));
return (error);
}
int
kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
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{
struct proc *p = td->td_proc;
int oonstack;
oonstack = sigonstack(cpu_getstack(td));
if (oss != NULL) {
*oss = td->td_sigstk;
oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
}
if (ss != NULL) {
if (oonstack)
return (EPERM);
if ((ss->ss_flags & ~SS_DISABLE) != 0)
return (EINVAL);
if (!(ss->ss_flags & SS_DISABLE)) {
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (ss->ss_size < p->p_sysent->sv_minsigstksz)
return (ENOMEM);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
td->td_sigstk = *ss;
td->td_pflags |= TDP_ALTSTACK;
} else {
td->td_pflags &= ~TDP_ALTSTACK;
}
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}
return (0);
1994-05-24 10:09:53 +00:00
}
/*
* Common code for kill process group/broadcast kill.
* cp is calling process.
*/
static int
killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
{
struct proc *p;
struct pgrp *pgrp;
int err;
int ret;
1995-05-30 08:16:23 +00:00
ret = ESRCH;
if (all) {
1995-05-30 08:16:23 +00:00
/*
* broadcast
*/
sx_slock(&allproc_lock);
FOREACH_PROC_IN_SYSTEM(p) {
PROC_LOCK(p);
if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
p == td->td_proc || p->p_state == PRS_NEW) {
PROC_UNLOCK(p);
continue;
}
err = p_cansignal(td, p, sig);
if (err == 0) {
if (sig)
pksignal(p, sig, ksi);
ret = err;
}
else if (ret == ESRCH)
ret = err;
PROC_UNLOCK(p);
}
sx_sunlock(&allproc_lock);
} else {
sx_slock(&proctree_lock);
if (pgid == 0) {
1995-05-30 08:16:23 +00:00
/*
* zero pgid means send to my process group.
*/
pgrp = td->td_proc->p_pgrp;
PGRP_LOCK(pgrp);
} else {
pgrp = pgfind(pgid);
if (pgrp == NULL) {
sx_sunlock(&proctree_lock);
return (ESRCH);
}
}
sx_sunlock(&proctree_lock);
LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
PROC_LOCK(p);
if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
2011-03-23 13:44:32 +00:00
p->p_state == PRS_NEW) {
PROC_UNLOCK(p);
continue;
}
err = p_cansignal(td, p, sig);
if (err == 0) {
if (sig)
pksignal(p, sig, ksi);
ret = err;
}
else if (ret == ESRCH)
ret = err;
PROC_UNLOCK(p);
}
PGRP_UNLOCK(pgrp);
}
return (ret);
}
#ifndef _SYS_SYSPROTO_H_
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struct kill_args {
int pid;
int signum;
};
#endif
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/* ARGSUSED */
int
sys_kill(struct thread *td, struct kill_args *uap)
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{
ksiginfo_t ksi;
struct proc *p;
int error;
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AUDIT_ARG_SIGNUM(uap->signum);
AUDIT_ARG_PID(uap->pid);
if ((u_int)uap->signum > _SIG_MAXSIG)
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return (EINVAL);
ksiginfo_init(&ksi);
ksi.ksi_signo = uap->signum;
ksi.ksi_code = SI_USER;
ksi.ksi_pid = td->td_proc->p_pid;
ksi.ksi_uid = td->td_ucred->cr_ruid;
1994-05-24 10:09:53 +00:00
if (uap->pid > 0) {
/* kill single process */
if ((p = pfind(uap->pid)) == NULL) {
if ((p = zpfind(uap->pid)) == NULL)
return (ESRCH);
}
AUDIT_ARG_PROCESS(p);
error = p_cansignal(td, p, uap->signum);
if (error == 0 && uap->signum)
pksignal(p, uap->signum, &ksi);
PROC_UNLOCK(p);
return (error);
}
switch (uap->pid) {
case -1: /* broadcast signal */
return (killpg1(td, uap->signum, 0, 1, &ksi));
case 0: /* signal own process group */
return (killpg1(td, uap->signum, 0, 0, &ksi));
default: /* negative explicit process group */
return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1994-05-24 10:09:53 +00:00
}
/* NOTREACHED */
1994-05-24 10:09:53 +00:00
}
int
sys_pdkill(td, uap)
struct thread *td;
struct pdkill_args *uap;
{
#ifdef PROCDESC
struct proc *p;
int error;
AUDIT_ARG_SIGNUM(uap->signum);
AUDIT_ARG_FD(uap->fd);
if ((u_int)uap->signum > _SIG_MAXSIG)
return (EINVAL);
error = procdesc_find(td, uap->fd, CAP_PDKILL, &p);
if (error)
return (error);
AUDIT_ARG_PROCESS(p);
error = p_cansignal(td, p, uap->signum);
if (error == 0 && uap->signum)
kern_psignal(p, uap->signum);
PROC_UNLOCK(p);
return (error);
#else
return (ENOSYS);
#endif
}
#if defined(COMPAT_43)
#ifndef _SYS_SYSPROTO_H_
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struct okillpg_args {
int pgid;
int signum;
};
#endif
1994-05-24 10:09:53 +00:00
/* ARGSUSED */
int
okillpg(struct thread *td, struct okillpg_args *uap)
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{
ksiginfo_t ksi;
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AUDIT_ARG_SIGNUM(uap->signum);
AUDIT_ARG_PID(uap->pgid);
if ((u_int)uap->signum > _SIG_MAXSIG)
1994-05-24 10:09:53 +00:00
return (EINVAL);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksiginfo_init(&ksi);
ksi.ksi_signo = uap->signum;
ksi.ksi_code = SI_USER;
ksi.ksi_pid = td->td_proc->p_pid;
ksi.ksi_uid = td->td_ucred->cr_ruid;
return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1994-05-24 10:09:53 +00:00
}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
#ifndef _SYS_SYSPROTO_H_
struct sigqueue_args {
pid_t pid;
int signum;
/* union sigval */ void *value;
};
#endif
int
sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
{
ksiginfo_t ksi;
struct proc *p;
int error;
if ((u_int)uap->signum > _SIG_MAXSIG)
return (EINVAL);
/*
* Specification says sigqueue can only send signal to
* single process.
*/
if (uap->pid <= 0)
return (EINVAL);
if ((p = pfind(uap->pid)) == NULL) {
if ((p = zpfind(uap->pid)) == NULL)
return (ESRCH);
}
error = p_cansignal(td, p, uap->signum);
if (error == 0 && uap->signum != 0) {
ksiginfo_init(&ksi);
ksi.ksi_flags = KSI_SIGQ;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksi.ksi_signo = uap->signum;
ksi.ksi_code = SI_QUEUE;
ksi.ksi_pid = td->td_proc->p_pid;
ksi.ksi_uid = td->td_ucred->cr_ruid;
ksi.ksi_value.sival_ptr = uap->value;
error = pksignal(p, ksi.ksi_signo, &ksi);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
}
PROC_UNLOCK(p);
return (error);
}
1994-05-24 10:09:53 +00:00
/*
* Send a signal to a process group.
*/
void
gsignal(int pgid, int sig, ksiginfo_t *ksi)
1994-05-24 10:09:53 +00:00
{
struct pgrp *pgrp;
if (pgid != 0) {
sx_slock(&proctree_lock);
pgrp = pgfind(pgid);
sx_sunlock(&proctree_lock);
if (pgrp != NULL) {
pgsignal(pgrp, sig, 0, ksi);
PGRP_UNLOCK(pgrp);
}
}
1994-05-24 10:09:53 +00:00
}
/*
* Send a signal to a process group. If checktty is 1,
1994-05-24 10:09:53 +00:00
* limit to members which have a controlling terminal.
*/
void
pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1994-05-24 10:09:53 +00:00
{
struct proc *p;
1994-05-24 10:09:53 +00:00
if (pgrp) {
PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
PROC_LOCK(p);
if (p->p_state == PRS_NORMAL &&
(checkctty == 0 || p->p_flag & P_CONTROLT))
pksignal(p, sig, ksi);
PROC_UNLOCK(p);
}
}
1994-05-24 10:09:53 +00:00
}
/*
* Send a signal caused by a trap to the current thread. If it will be
* caught immediately, deliver it with correct code. Otherwise, post it
* normally.
1994-05-24 10:09:53 +00:00
*/
void
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
trapsignal(struct thread *td, ksiginfo_t *ksi)
1994-05-24 10:09:53 +00:00
{
struct sigacts *ps;
sigset_t mask;
struct proc *p;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
int sig;
int code;
p = td->td_proc;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sig = ksi->ksi_signo;
code = ksi->ksi_code;
KASSERT(_SIG_VALID(sig), ("invalid signal"));
PROC_LOCK(p);
ps = p->p_sigacts;
mtx_lock(&ps->ps_mtx);
if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
!SIGISMEMBER(td->td_sigmask, sig)) {
td->td_ru.ru_nsignals++;
1994-05-24 10:09:53 +00:00
#ifdef KTRACE
if (KTRPOINT(curthread, KTR_PSIG))
ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
&td->td_sigmask, code);
1994-05-24 10:09:53 +00:00
#endif
(*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
ksi, &td->td_sigmask);
mask = ps->ps_catchmask[_SIG_IDX(sig)];
if (!SIGISMEMBER(ps->ps_signodefer, sig))
SIGADDSET(mask, sig);
kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
if (SIGISMEMBER(ps->ps_sigreset, sig)) {
/*
* See kern_sigaction() for origin of this code.
*/
SIGDELSET(ps->ps_sigcatch, sig);
if (sig != SIGCONT &&
sigprop(sig) & SA_IGNORE)
SIGADDSET(ps->ps_sigignore, sig);
ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
}
mtx_unlock(&ps->ps_mtx);
} else {
/*
* Avoid a possible infinite loop if the thread
* masking the signal or process is ignoring the
* signal.
*/
if (kern_forcesigexit &&
(SIGISMEMBER(td->td_sigmask, sig) ||
ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
SIGDELSET(td->td_sigmask, sig);
SIGDELSET(ps->ps_sigcatch, sig);
SIGDELSET(ps->ps_sigignore, sig);
ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
}
mtx_unlock(&ps->ps_mtx);
p->p_code = code; /* XXX for core dump/debugger */
p->p_sig = sig; /* XXX to verify code */
tdsendsignal(p, td, sig, ksi);
1994-05-24 10:09:53 +00:00
}
PROC_UNLOCK(p);
1994-05-24 10:09:53 +00:00
}
static struct thread *
sigtd(struct proc *p, int sig, int prop)
{
struct thread *td, *signal_td;
PROC_LOCK_ASSERT(p, MA_OWNED);
/*
* Check if current thread can handle the signal without
2009-10-01 12:46:58 +00:00
* switching context to another thread.
*/
if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
return (curthread);
signal_td = NULL;
FOREACH_THREAD_IN_PROC(p, td) {
if (!SIGISMEMBER(td->td_sigmask, sig)) {
signal_td = td;
break;
}
}
if (signal_td == NULL)
signal_td = FIRST_THREAD_IN_PROC(p);
return (signal_td);
}
1994-05-24 10:09:53 +00:00
/*
* Send the signal to the process. If the signal has an action, the action
* is usually performed by the target process rather than the caller; we add
* the signal to the set of pending signals for the process.
*
* Exceptions:
* o When a stop signal is sent to a sleeping process that takes the
* default action, the process is stopped without awakening it.
* o SIGCONT restarts stopped processes (or puts them back to sleep)
* regardless of the signal action (eg, blocked or ignored).
*
* Other ignored signals are discarded immediately.
*
* NB: This function may be entered from the debugger via the "kill" DDB
* command. There is little that can be done to mitigate the possibly messy
* side effects of this unwise possibility.
1994-05-24 10:09:53 +00:00
*/
void
kern_psignal(struct proc *p, int sig)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
{
ksiginfo_t ksi;
ksiginfo_init(&ksi);
ksi.ksi_signo = sig;
ksi.ksi_code = SI_KERNEL;
(void) tdsendsignal(p, NULL, sig, &ksi);
}
int
pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
{
return (tdsendsignal(p, NULL, sig, ksi));
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
}
/* Utility function for finding a thread to send signal event to. */
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
int
sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
{
struct thread *td;
if (sigev->sigev_notify == SIGEV_THREAD_ID) {
td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
if (td == NULL)
return (ESRCH);
*ttd = td;
} else {
*ttd = NULL;
PROC_LOCK(p);
}
return (0);
}
void
tdsignal(struct thread *td, int sig)
{
ksiginfo_t ksi;
ksiginfo_init(&ksi);
ksi.ksi_signo = sig;
ksi.ksi_code = SI_KERNEL;
(void) tdsendsignal(td->td_proc, td, sig, &ksi);
}
void
tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
{
(void) tdsendsignal(td->td_proc, td, sig, ksi);
}
int
tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
{
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sig_t action;
sigqueue_t *sigqueue;
int prop;
struct sigacts *ps;
int intrval;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
int ret = 0;
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
int wakeup_swapper;
1994-05-24 10:09:53 +00:00
MPASS(td == NULL || p == td->td_proc);
PROC_LOCK_ASSERT(p, MA_OWNED);
if (!_SIG_VALID(sig))
2010-07-20 02:23:12 +00:00
panic("%s(): invalid signal %d", __func__, sig);
2010-07-20 02:23:12 +00:00
KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
/*
* IEEE Std 1003.1-2001: return success when killing a zombie.
*/
if (p->p_state == PRS_ZOMBIE) {
if (ksi && (ksi->ksi_flags & KSI_INS))
ksiginfo_tryfree(ksi);
return (ret);
}
ps = p->p_sigacts;
KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
prop = sigprop(sig);
if (td == NULL) {
td = sigtd(p, sig, prop);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
sigqueue = &p->p_sigqueue;
} else {
KASSERT(td->td_proc == p, ("invalid thread"));
sigqueue = &td->td_sigqueue;
}
SDT_PROBE(proc, kernel, , signal_send, td, p, sig, 0, 0 );
1994-05-24 10:09:53 +00:00
/*
* If the signal is being ignored,
* then we forget about it immediately.
* (Note: we don't set SIGCONT in ps_sigignore,
* and if it is set to SIG_IGN,
* action will be SIG_DFL here.)
1994-05-24 10:09:53 +00:00
*/
mtx_lock(&ps->ps_mtx);
if (SIGISMEMBER(ps->ps_sigignore, sig)) {
SDT_PROBE(proc, kernel, , signal_discard, td, p, sig, 0, 0 );
mtx_unlock(&ps->ps_mtx);
if (ksi && (ksi->ksi_flags & KSI_INS))
ksiginfo_tryfree(ksi);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
return (ret);
1994-05-24 10:09:53 +00:00
}
if (SIGISMEMBER(td->td_sigmask, sig))
action = SIG_HOLD;
else if (SIGISMEMBER(ps->ps_sigcatch, sig))
action = SIG_CATCH;
else
action = SIG_DFL;
if (SIGISMEMBER(ps->ps_sigintr, sig))
intrval = EINTR;
else
intrval = ERESTART;
mtx_unlock(&ps->ps_mtx);
1994-05-24 10:09:53 +00:00
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (prop & SA_CONT)
sigqueue_delete_stopmask_proc(p);
else if (prop & SA_STOP) {
1994-05-24 10:09:53 +00:00
/*
* If sending a tty stop signal to a member of an orphaned
* process group, discard the signal here if the action
* is default; don't stop the process below if sleeping,
* and don't clear any pending SIGCONT.
*/
if ((prop & SA_TTYSTOP) &&
(p->p_pgrp->pg_jobc == 0) &&
(action == SIG_DFL)) {
if (ksi && (ksi->ksi_flags & KSI_INS))
ksiginfo_tryfree(ksi);
return (ret);
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete_proc(p, SIGCONT);
if (p->p_flag & P_CONTINUED) {
p->p_flag &= ~P_CONTINUED;
PROC_LOCK(p->p_pptr);
sigqueue_take(p->p_ksi);
PROC_UNLOCK(p->p_pptr);
}
1994-05-24 10:09:53 +00:00
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ret = sigqueue_add(sigqueue, sig, ksi);
if (ret != 0)
return (ret);
signotify(td);
/*
* Defer further processing for signals which are held,
* except that stopped processes must be continued by SIGCONT.
*/
if (action == SIG_HOLD &&
!((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
return (ret);
/*
* SIGKILL: Remove procfs STOPEVENTs.
*/
if (sig == SIGKILL) {
/* from procfs_ioctl.c: PIOCBIC */
p->p_stops = 0;
/* from procfs_ioctl.c: PIOCCONT */
p->p_step = 0;
wakeup(&p->p_step);
}
1994-05-24 10:09:53 +00:00
/*
* Some signals have a process-wide effect and a per-thread
* component. Most processing occurs when the process next
* tries to cross the user boundary, however there are some
* times when processing needs to be done immediatly, such as
* waking up threads so that they can cross the user boundary.
* We try do the per-process part here.
1994-05-24 10:09:53 +00:00
*/
if (P_SHOULDSTOP(p)) {
KASSERT(!(p->p_flag & P_WEXIT),
("signal to stopped but exiting process"));
if (sig == SIGKILL) {
2010-09-01 01:26:07 +00:00
/*
* If traced process is already stopped,
* then no further action is necessary.
*/
if (p->p_flag & P_TRACED)
goto out;
/*
* SIGKILL sets process running.
* It will die elsewhere.
* All threads must be restarted.
*/
p->p_flag &= ~P_STOPPED_SIG;
goto runfast;
}
if (prop & SA_CONT) {
2010-09-01 01:26:07 +00:00
/*
* If traced process is already stopped,
* then no further action is necessary.
*/
if (p->p_flag & P_TRACED)
goto out;
/*
* If SIGCONT is default (or ignored), we continue the
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
* process but don't leave the signal in sigqueue as
* it has no further action. If SIGCONT is held, we
* continue the process and leave the signal in
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
* sigqueue. If the process catches SIGCONT, let it
* handle the signal itself. If it isn't waiting on
* an event, it goes back to run state.
* Otherwise, process goes back to sleep state.
*/
p->p_flag &= ~P_STOPPED_SIG;
PROC_SLOCK(p);
if (p->p_numthreads == p->p_suspcount) {
PROC_SUNLOCK(p);
p->p_flag |= P_CONTINUED;
p->p_xstat = SIGCONT;
PROC_LOCK(p->p_pptr);
childproc_continued(p);
PROC_UNLOCK(p->p_pptr);
PROC_SLOCK(p);
}
if (action == SIG_DFL) {
thread_unsuspend(p);
PROC_SUNLOCK(p);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete(sigqueue, sig);
goto out;
}
if (action == SIG_CATCH) {
/*
* The process wants to catch it so it needs
* to run at least one thread, but which one?
*/
PROC_SUNLOCK(p);
goto runfast;
}
/*
* The signal is not ignored or caught.
*/
thread_unsuspend(p);
PROC_SUNLOCK(p);
1994-05-24 10:09:53 +00:00
goto out;
}
if (prop & SA_STOP) {
2010-09-01 01:26:07 +00:00
/*
* If traced process is already stopped,
* then no further action is necessary.
*/
if (p->p_flag & P_TRACED)
goto out;
/*
* Already stopped, don't need to stop again
* (If we did the shell could get confused).
* Just make sure the signal STOP bit set.
*/
p->p_flag |= P_STOPPED_SIG;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete(sigqueue, sig);
goto out;
}
1994-05-24 10:09:53 +00:00
/*
* All other kinds of signals:
* If a thread is sleeping interruptibly, simulate a
* wakeup so that when it is continued it will be made
* runnable and can look at the signal. However, don't make
* the PROCESS runnable, leave it stopped.
* It may run a bit until it hits a thread_suspend_check().
1994-05-24 10:09:53 +00:00
*/
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
wakeup_swapper = 0;
PROC_SLOCK(p);
thread_lock(td);
Switch the sleep/wakeup and condition variable implementations to use the sleep queue interface: - Sleep queues attempt to merge some of the benefits of both sleep queues and condition variables. Having sleep qeueus in a hash table avoids having to allocate a queue head for each wait channel. Thus, struct cv has shrunk down to just a single char * pointer now. However, the hash table does not hold threads directly, but queue heads. This means that once you have located a queue in the hash bucket, you no longer have to walk the rest of the hash chain looking for threads. Instead, you have a list of all the threads sleeping on that wait channel. - Outside of the sleepq code and the sleep/cv code the kernel no longer differentiates between cv's and sleep/wakeup. For example, calls to abortsleep() and cv_abort() are replaced with a call to sleepq_abort(). Thus, the TDF_CVWAITQ flag is removed. Also, calls to unsleep() and cv_waitq_remove() have been replaced with calls to sleepq_remove(). - The sched_sleep() function no longer accepts a priority argument as sleep's no longer inherently bump the priority. Instead, this is soley a propery of msleep() which explicitly calls sched_prio() before blocking. - The TDF_ONSLEEPQ flag has been dropped as it was never used. The associated TDF_SET_ONSLEEPQ and TDF_CLR_ON_SLEEPQ macros have also been dropped and replaced with a single explicit clearing of td_wchan. TD_SET_ONSLEEPQ() would really have only made sense if it had taken the wait channel and message as arguments anyway. Now that that only happens in one place, a macro would be overkill.
2004-02-27 18:52:44 +00:00
if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
wakeup_swapper = sleepq_abort(td, intrval);
thread_unlock(td);
PROC_SUNLOCK(p);
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
if (wakeup_swapper)
kick_proc0();
goto out;
1994-05-24 10:09:53 +00:00
/*
2004-03-29 22:46:54 +00:00
* Mutexes are short lived. Threads waiting on them will
* hit thread_suspend_check() soon.
1994-05-24 10:09:53 +00:00
*/
} else if (p->p_state == PRS_NORMAL) {
if (p->p_flag & P_TRACED || action == SIG_CATCH) {
tdsigwakeup(td, sig, action, intrval);
1994-05-24 10:09:53 +00:00
goto out;
}
MPASS(action == SIG_DFL);
In the kernel code, we have the tsleep() call with the PCATCH argument. PCATCH means 'if we get a signal, interrupt me!" and tsleep returns either EINTR or ERESTART depending on the circumstances. ERESTART is "special" because it causes the system call to fail, but right as it returns back to userland it tells the trap handler to move %eip back a bit so that userland will immediately re-run the syscall. This is a syscall restart. It only works for things like read() etc where nothing has changed yet. Note that *userland* is tricked into restarting the syscall by the kernel. The kernel doesn't actually do the restart. It is deadly for things like select, poll, nanosleep etc where it might cause the elapsed time to be reset and start again from scratch. So those syscalls do this to prevent userland rerunning the syscall: if (error == ERESTART) error = EINTR; Fake "signals" like SIGTSTP from ^Z etc do not normally invoke userland signal handlers. But, in -current, the PCATCH *is* being triggered and tsleep is returning ERESTART, and the syscall is aborted even though no userland signal handler was run. That is the fault here. We're triggering the PCATCH in cases that we shouldn't. ie: it is being triggered on *any* signal processing, rather than the case where the signal is posted to userland. --- Peter The work of psignal() is a patchwork of special case required by the process debugging and job-control facilities... --- Kirk McKusick "The design and impelementation of the 4.4BSD Operating system" Page 105 in STABLE source, when psignal is posting a STOP signal to sleeping process and the signal action of the process is SIG_DFL, system will directly change the process state from SSLEEP to SSTOP, and when SIGCONT is posted to the stopped process, if it finds that the process is still on sleep queue, the process state will be restored to SSLEEP, and won't wakeup the process. this commit mimics the behaviour in STABLE source tree. Reviewed by: Jon Mini, Tim Robbins, Peter Wemm Approved by: julian@freebsd.org (mentor)
2002-09-03 12:56:01 +00:00
if (prop & SA_STOP) {
if (p->p_flag & (P_PPWAIT|P_WEXIT))
In the kernel code, we have the tsleep() call with the PCATCH argument. PCATCH means 'if we get a signal, interrupt me!" and tsleep returns either EINTR or ERESTART depending on the circumstances. ERESTART is "special" because it causes the system call to fail, but right as it returns back to userland it tells the trap handler to move %eip back a bit so that userland will immediately re-run the syscall. This is a syscall restart. It only works for things like read() etc where nothing has changed yet. Note that *userland* is tricked into restarting the syscall by the kernel. The kernel doesn't actually do the restart. It is deadly for things like select, poll, nanosleep etc where it might cause the elapsed time to be reset and start again from scratch. So those syscalls do this to prevent userland rerunning the syscall: if (error == ERESTART) error = EINTR; Fake "signals" like SIGTSTP from ^Z etc do not normally invoke userland signal handlers. But, in -current, the PCATCH *is* being triggered and tsleep is returning ERESTART, and the syscall is aborted even though no userland signal handler was run. That is the fault here. We're triggering the PCATCH in cases that we shouldn't. ie: it is being triggered on *any* signal processing, rather than the case where the signal is posted to userland. --- Peter The work of psignal() is a patchwork of special case required by the process debugging and job-control facilities... --- Kirk McKusick "The design and impelementation of the 4.4BSD Operating system" Page 105 in STABLE source, when psignal is posting a STOP signal to sleeping process and the signal action of the process is SIG_DFL, system will directly change the process state from SSLEEP to SSTOP, and when SIGCONT is posted to the stopped process, if it finds that the process is still on sleep queue, the process state will be restored to SSLEEP, and won't wakeup the process. this commit mimics the behaviour in STABLE source tree. Reviewed by: Jon Mini, Tim Robbins, Peter Wemm Approved by: julian@freebsd.org (mentor)
2002-09-03 12:56:01 +00:00
goto out;
p->p_flag |= P_STOPPED_SIG;
p->p_xstat = sig;
PROC_SLOCK(p);
sig_suspend_threads(td, p, 1);
if (p->p_numthreads == p->p_suspcount) {
/*
* only thread sending signal to another
* process can reach here, if thread is sending
* signal to its process, because thread does
* not suspend itself here, p_numthreads
* should never be equal to p_suspcount.
*/
thread_stopped(p);
PROC_SUNLOCK(p);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete_proc(p, p->p_xstat);
} else
PROC_SUNLOCK(p);
In the kernel code, we have the tsleep() call with the PCATCH argument. PCATCH means 'if we get a signal, interrupt me!" and tsleep returns either EINTR or ERESTART depending on the circumstances. ERESTART is "special" because it causes the system call to fail, but right as it returns back to userland it tells the trap handler to move %eip back a bit so that userland will immediately re-run the syscall. This is a syscall restart. It only works for things like read() etc where nothing has changed yet. Note that *userland* is tricked into restarting the syscall by the kernel. The kernel doesn't actually do the restart. It is deadly for things like select, poll, nanosleep etc where it might cause the elapsed time to be reset and start again from scratch. So those syscalls do this to prevent userland rerunning the syscall: if (error == ERESTART) error = EINTR; Fake "signals" like SIGTSTP from ^Z etc do not normally invoke userland signal handlers. But, in -current, the PCATCH *is* being triggered and tsleep is returning ERESTART, and the syscall is aborted even though no userland signal handler was run. That is the fault here. We're triggering the PCATCH in cases that we shouldn't. ie: it is being triggered on *any* signal processing, rather than the case where the signal is posted to userland. --- Peter The work of psignal() is a patchwork of special case required by the process debugging and job-control facilities... --- Kirk McKusick "The design and impelementation of the 4.4BSD Operating system" Page 105 in STABLE source, when psignal is posting a STOP signal to sleeping process and the signal action of the process is SIG_DFL, system will directly change the process state from SSLEEP to SSTOP, and when SIGCONT is posted to the stopped process, if it finds that the process is still on sleep queue, the process state will be restored to SSLEEP, and won't wakeup the process. this commit mimics the behaviour in STABLE source tree. Reviewed by: Jon Mini, Tim Robbins, Peter Wemm Approved by: julian@freebsd.org (mentor)
2002-09-03 12:56:01 +00:00
goto out;
}
} else {
/* Not in "NORMAL" state. discard the signal. */
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete(sigqueue, sig);
goto out;
}
1994-05-24 10:09:53 +00:00
/*
* The process is not stopped so we need to apply the signal to all the
* running threads.
*/
runfast:
tdsigwakeup(td, sig, action, intrval);
PROC_SLOCK(p);
thread_unsuspend(p);
PROC_SUNLOCK(p);
out:
/* If we jump here, proc slock should not be owned. */
PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
return (ret);
}
1994-05-24 10:09:53 +00:00
/*
* The force of a signal has been directed against a single
* thread. We need to see what we can do about knocking it
* out of any sleep it may be in etc.
*/
static void
tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
{
struct proc *p = td->td_proc;
register int prop;
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
int wakeup_swapper;
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
wakeup_swapper = 0;
PROC_LOCK_ASSERT(p, MA_OWNED);
prop = sigprop(sig);
PROC_SLOCK(p);
thread_lock(td);
/*
* Bring the priority of a thread up if we want it to get
* killed in this lifetime.
*/
if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
sched_prio(td, PUSER);
if (TD_ON_SLEEPQ(td)) {
/*
* If thread is sleeping uninterruptibly
* we can't interrupt the sleep... the signal will
* be noticed when the process returns through
* trap() or syscall().
*/
Switch the sleep/wakeup and condition variable implementations to use the sleep queue interface: - Sleep queues attempt to merge some of the benefits of both sleep queues and condition variables. Having sleep qeueus in a hash table avoids having to allocate a queue head for each wait channel. Thus, struct cv has shrunk down to just a single char * pointer now. However, the hash table does not hold threads directly, but queue heads. This means that once you have located a queue in the hash bucket, you no longer have to walk the rest of the hash chain looking for threads. Instead, you have a list of all the threads sleeping on that wait channel. - Outside of the sleepq code and the sleep/cv code the kernel no longer differentiates between cv's and sleep/wakeup. For example, calls to abortsleep() and cv_abort() are replaced with a call to sleepq_abort(). Thus, the TDF_CVWAITQ flag is removed. Also, calls to unsleep() and cv_waitq_remove() have been replaced with calls to sleepq_remove(). - The sched_sleep() function no longer accepts a priority argument as sleep's no longer inherently bump the priority. Instead, this is soley a propery of msleep() which explicitly calls sched_prio() before blocking. - The TDF_ONSLEEPQ flag has been dropped as it was never used. The associated TDF_SET_ONSLEEPQ and TDF_CLR_ON_SLEEPQ macros have also been dropped and replaced with a single explicit clearing of td_wchan. TD_SET_ONSLEEPQ() would really have only made sense if it had taken the wait channel and message as arguments anyway. Now that that only happens in one place, a macro would be overkill.
2004-02-27 18:52:44 +00:00
if ((td->td_flags & TDF_SINTR) == 0)
goto out;
1994-05-24 10:09:53 +00:00
/*
* If SIGCONT is default (or ignored) and process is
* asleep, we are finished; the process should not
* be awakened.
1994-05-24 10:09:53 +00:00
*/
if ((prop & SA_CONT) && action == SIG_DFL) {
thread_unlock(td);
PROC_SUNLOCK(p);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete(&p->p_sigqueue, sig);
/*
* It may be on either list in this state.
* Remove from both for now.
*/
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete(&td->td_sigqueue, sig);
return;
}
/*
* Give low priority threads a better chance to run.
*/
if (td->td_priority > PUSER)
sched_prio(td, PUSER);
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
wakeup_swapper = sleepq_abort(td, intrval);
} else {
1994-05-24 10:09:53 +00:00
/*
* Other states do nothing with the signal immediately,
1994-05-24 10:09:53 +00:00
* other than kicking ourselves if we are running.
* It will either never be noticed, or noticed very soon.
*/
#ifdef SMP
Switch the sleep/wakeup and condition variable implementations to use the sleep queue interface: - Sleep queues attempt to merge some of the benefits of both sleep queues and condition variables. Having sleep qeueus in a hash table avoids having to allocate a queue head for each wait channel. Thus, struct cv has shrunk down to just a single char * pointer now. However, the hash table does not hold threads directly, but queue heads. This means that once you have located a queue in the hash bucket, you no longer have to walk the rest of the hash chain looking for threads. Instead, you have a list of all the threads sleeping on that wait channel. - Outside of the sleepq code and the sleep/cv code the kernel no longer differentiates between cv's and sleep/wakeup. For example, calls to abortsleep() and cv_abort() are replaced with a call to sleepq_abort(). Thus, the TDF_CVWAITQ flag is removed. Also, calls to unsleep() and cv_waitq_remove() have been replaced with calls to sleepq_remove(). - The sched_sleep() function no longer accepts a priority argument as sleep's no longer inherently bump the priority. Instead, this is soley a propery of msleep() which explicitly calls sched_prio() before blocking. - The TDF_ONSLEEPQ flag has been dropped as it was never used. The associated TDF_SET_ONSLEEPQ and TDF_CLR_ON_SLEEPQ macros have also been dropped and replaced with a single explicit clearing of td_wchan. TD_SET_ONSLEEPQ() would really have only made sense if it had taken the wait channel and message as arguments anyway. Now that that only happens in one place, a macro would be overkill.
2004-02-27 18:52:44 +00:00
if (TD_IS_RUNNING(td) && td != curthread)
forward_signal(td);
#endif
}
out:
PROC_SUNLOCK(p);
thread_unlock(td);
If a thread that is swapped out is made runnable, then the setrunnable() routine wakes up proc0 so that proc0 can swap the thread back in. Historically, this has been done by waking up proc0 directly from setrunnable() itself via a wakeup(). When waking up a sleeping thread that was swapped out (the usual case when waking proc0 since only sleeping threads are eligible to be swapped out), this resulted in a bit of recursion (e.g. wakeup() -> setrunnable() -> wakeup()). With sleep queues having separate locks in 6.x and later, this caused a spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock). An attempt was made to fix this in 7.0 by making the proc0 wakeup use the ithread mechanism for doing the wakeup. However, this required grabbing proc0's thread lock to perform the wakeup. If proc0 was asleep elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated into the same LOR since the thread lock would be some other sleepq lock. Fix this by deferring the wakeup of the swapper until after the sleepq lock held by the upper layer has been locked. The setrunnable() routine now returns a boolean value to indicate whether or not proc0 needs to be woken up. The end result is that consumers of the sleepq API such as *sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup proc0 if they get a non-zero return value from sleepq_abort(), sleepq_broadcast(), or sleepq_signal(). Discussed with: jeff Glanced at by: sam Tested by: Jurgen Weber jurgen - ish com au MFC after: 2 weeks
2008-08-05 20:02:31 +00:00
if (wakeup_swapper)
kick_proc0();
1994-05-24 10:09:53 +00:00
}
static void
sig_suspend_threads(struct thread *td, struct proc *p, int sending)
{
struct thread *td2;
int wakeup_swapper;
PROC_LOCK_ASSERT(p, MA_OWNED);
PROC_SLOCK_ASSERT(p, MA_OWNED);
wakeup_swapper = 0;
FOREACH_THREAD_IN_PROC(p, td2) {
thread_lock(td2);
td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
(td2->td_flags & TDF_SINTR)) {
if (td2->td_flags & TDF_SBDRY) {
if (TD_IS_SUSPENDED(td2))
wakeup_swapper |=
thread_unsuspend_one(td2);
if (TD_ON_SLEEPQ(td2))
wakeup_swapper |=
sleepq_abort(td2, ERESTART);
} else if (!TD_IS_SUSPENDED(td2)) {
thread_suspend_one(td2);
}
} else if (!TD_IS_SUSPENDED(td2)) {
if (sending || td != td2)
td2->td_flags |= TDF_ASTPENDING;
#ifdef SMP
if (TD_IS_RUNNING(td2) && td2 != td)
forward_signal(td2);
#endif
}
thread_unlock(td2);
}
if (wakeup_swapper)
kick_proc0();
}
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
int
ptracestop(struct thread *td, int sig)
{
struct proc *p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
&p->p_mtx.lock_object, "Stopping for traced signal");
td->td_dbgflags |= TDB_XSIG;
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
td->td_xsig = sig;
PROC_SLOCK(p);
while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
if (p->p_flag & P_SINGLE_EXIT) {
td->td_dbgflags &= ~TDB_XSIG;
PROC_SUNLOCK(p);
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
return (sig);
}
/*
* Just make wait() to work, the last stopped thread
* will win.
*/
p->p_xstat = sig;
p->p_xthread = td;
p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
sig_suspend_threads(td, p, 0);
if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
td->td_dbgflags &= ~TDB_STOPATFORK;
cv_broadcast(&p->p_dbgwait);
}
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
stopme:
thread_suspend_switch(td);
if (p->p_xthread == td)
p->p_xthread = NULL;
if (!(p->p_flag & P_TRACED))
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
break;
if (td->td_dbgflags & TDB_SUSPEND) {
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
if (p->p_flag & P_SINGLE_EXIT)
break;
goto stopme;
}
}
PROC_SUNLOCK(p);
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
return (td->td_xsig);
}
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
static void
reschedule_signals(struct proc *p, sigset_t block, int flags)
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
{
struct sigacts *ps;
struct thread *td;
int sig;
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
PROC_LOCK_ASSERT(p, MA_OWNED);
if (SIGISEMPTY(p->p_siglist))
return;
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
ps = p->p_sigacts;
SIGSETAND(block, p->p_siglist);
while ((sig = sig_ffs(&block)) != 0) {
SIGDELSET(block, sig);
td = sigtd(p, sig, 0);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
signotify(td);
if (!(flags & SIGPROCMASK_PS_LOCKED))
mtx_lock(&ps->ps_mtx);
if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
tdsigwakeup(td, sig, SIG_CATCH,
(SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
ERESTART));
if (!(flags & SIGPROCMASK_PS_LOCKED))
mtx_unlock(&ps->ps_mtx);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
}
}
void
tdsigcleanup(struct thread *td)
{
struct proc *p;
sigset_t unblocked;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
sigqueue_flush(&td->td_sigqueue);
if (p->p_numthreads == 1)
return;
/*
* Since we cannot handle signals, notify signal post code
* about this by filling the sigmask.
*
* Also, if needed, wake up thread(s) that do not block the
* same signals as the exiting thread, since the thread might
* have been selected for delivery and woken up.
*/
SIGFILLSET(unblocked);
SIGSETNAND(unblocked, td->td_sigmask);
SIGFILLSET(td->td_sigmask);
reschedule_signals(p, unblocked, 0);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
}
1994-05-24 10:09:53 +00:00
/*
* If the current process has received a signal (should be caught or cause
* termination, should interrupt current syscall), return the signal number.
* Stop signals with default action are processed immediately, then cleared;
* they aren't returned. This is checked after each entry to the system for
* a syscall or trap (though this can usually be done without calling issignal
* by checking the pending signal masks in cursig.) The normal call
1994-05-24 10:09:53 +00:00
* sequence is
*
* while (sig = cursig(curthread))
* postsig(sig);
1994-05-24 10:09:53 +00:00
*/
static int
issignal(struct thread *td, int stop_allowed)
1994-05-24 10:09:53 +00:00
{
struct proc *p;
struct sigacts *ps;
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
struct sigqueue *queue;
sigset_t sigpending;
int sig, prop, newsig;
1994-05-24 10:09:53 +00:00
p = td->td_proc;
ps = p->p_sigacts;
mtx_assert(&ps->ps_mtx, MA_OWNED);
PROC_LOCK_ASSERT(p, MA_OWNED);
1994-05-24 10:09:53 +00:00
for (;;) {
int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigpending = td->td_sigqueue.sq_signals;
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
SIGSETNAND(sigpending, td->td_sigmask);
1994-05-24 10:09:53 +00:00
if (p->p_flag & P_PPWAIT)
SIG_STOPSIGMASK(sigpending);
if (SIGISEMPTY(sigpending)) /* no signal to send */
1994-05-24 10:09:53 +00:00
return (0);
sig = sig_ffs(&sigpending);
if (p->p_stops & S_SIG) {
mtx_unlock(&ps->ps_mtx);
stopevent(p, S_SIG, sig);
mtx_lock(&ps->ps_mtx);
}
1994-05-24 10:09:53 +00:00
/*
* We should see pending but ignored signals
* only if P_TRACED was on when they were posted.
*/
if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete(&td->td_sigqueue, sig);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
sigqueue_delete(&p->p_sigqueue, sig);
1994-05-24 10:09:53 +00:00
continue;
}
if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
/*
* If traced, always stop.
* Remove old signal from queue before the stop.
* XXX shrug off debugger, it causes siginfo to
* be thrown away.
1994-05-24 10:09:53 +00:00
*/
queue = &td->td_sigqueue;
td->td_dbgksi.ksi_signo = 0;
if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
queue = &p->p_sigqueue;
sigqueue_get(queue, sig, &td->td_dbgksi);
}
mtx_unlock(&ps->ps_mtx);
Add code to support debugging threaded process. 1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel thread current user thread is running on. Add tm_dflags into kse_thr_mailbox, the flags is written by debugger, it tells UTS and kernel what should be done when the process is being debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER. TMDF_SSTEP is used to tell kernel to turn on single stepping, or turn off if it is not set. TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall whenever possible, to UTS, it means do not run the user thread until debugger clears it, this behaviour is necessary because gdb wants to resume only one thread when the thread's pc is at a breakpoint, and thread needs to go forward, in order to avoid other threads sneak pass the breakpoints, it needs to remove breakpoint, only wants one thread to go. Also, add km_lwp to kse_mailbox, the lwp id is copied to kse_thr_mailbox at context switch time when process is not being debugged, so when process is attached, debugger can map kernel thread to user thread. 2. Add p_xthread to proc strcuture and td_xsig to thread structure. p_xthread is used by a thread when it wants to report event to debugger, every thread can set the pointer, especially, when it is used in ptracestop, it is the last thread reporting event will win the race. Every thread has a td_xsig to exchange signal with debugger, thread uses TDF_XSIG flag to indicate it is reporting signal to debugger, if the flag is not cleared, thread will keep retrying until it is cleared by debugger, p_xthread may be used by debugger to indicate CURRENT thread. The p_xstat is still in proc structure to keep wait() to work, in future, we may just use td_xsig. 3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend a thread. When process stops, debugger can set the flag for thread, thread will check the flag in thread_suspend_check, enters a loop, unless it is cleared by debugger, process is detached or process is existing. The flag is also checked in ptracestop, so debugger can temporarily suspend a thread even if the thread wants to exchange signal. 4. Current, in ptrace, we always resume all threads, but if a thread has already a TDF_DBSUSPEND flag set by debugger, it won't run. Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
newsig = ptracestop(td, sig);
mtx_lock(&ps->ps_mtx);
1994-05-24 10:09:53 +00:00
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (sig != newsig) {
/*
* If parent wants us to take the signal,
* then it will leave it in p->p_xstat;
* otherwise we just look for signals again.
*/
if (newsig == 0)
continue;
sig = newsig;
/*
* Put the new signal into td_sigqueue. If the
* signal is being masked, look for other signals.
*/
sigqueue_add(queue, sig, NULL);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
if (SIGISMEMBER(td->td_sigmask, sig))
continue;
signotify(td);
} else {
if (td->td_dbgksi.ksi_signo != 0) {
td->td_dbgksi.ksi_flags |= KSI_HEAD;
if (sigqueue_add(&td->td_sigqueue, sig,
&td->td_dbgksi) != 0)
td->td_dbgksi.ksi_signo = 0;
}
if (td->td_dbgksi.ksi_signo == 0)
sigqueue_add(&td->td_sigqueue, sig,
NULL);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
}
/*
* If the traced bit got turned off, go back up
* to the top to rescan signals. This ensures
* that p_sig* and p_sigact are consistent.
*/
if ((p->p_flag & P_TRACED) == 0)
continue;
1994-05-24 10:09:53 +00:00
}
prop = sigprop(sig);
1994-05-24 10:09:53 +00:00
/*
* Decide whether the signal should be returned.
* Return the signal's number, or fall through
* to clear it from the pending mask.
*/
switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
1994-05-24 10:09:53 +00:00
case (intptr_t)SIG_DFL:
1994-05-24 10:09:53 +00:00
/*
* Don't take default actions on system processes.
*/
if (p->p_pid <= 1) {
#ifdef DIAGNOSTIC
/*
* Are you sure you want to ignore SIGSEGV
* in init? XXX
*/
printf("Process (pid %lu) got signal %d\n",
(u_long)p->p_pid, sig);
1994-05-24 10:09:53 +00:00
#endif
break; /* == ignore */
}
/*
* If there is a pending stop signal to process
* with default action, stop here,
* then clear the signal. However,
* if process is member of an orphaned
* process group, ignore tty stop signals.
*/
if (prop & SA_STOP) {
if (p->p_flag & (P_TRACED|P_WEXIT) ||
1994-05-24 10:09:53 +00:00
(p->p_pgrp->pg_jobc == 0 &&
prop & SA_TTYSTOP))
1994-05-24 10:09:53 +00:00
break; /* == ignore */
/* Ignore, but do not drop the stop signal. */
if (stop_allowed != SIG_STOP_ALLOWED)
return (sig);
mtx_unlock(&ps->ps_mtx);
WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
&p->p_mtx.lock_object, "Catching SIGSTOP");
p->p_flag |= P_STOPPED_SIG;
p->p_xstat = sig;
PROC_SLOCK(p);
sig_suspend_threads(td, p, 0);
thread_suspend_switch(td);
PROC_SUNLOCK(p);
mtx_lock(&ps->ps_mtx);
1994-05-24 10:09:53 +00:00
break;
} else if (prop & SA_IGNORE) {
1994-05-24 10:09:53 +00:00
/*
* Except for SIGCONT, shouldn't get here.
* Default action is to ignore; drop it.
*/
break; /* == ignore */
} else
return (sig);
1994-05-24 10:09:53 +00:00
/*NOTREACHED*/
case (intptr_t)SIG_IGN:
1994-05-24 10:09:53 +00:00
/*
* Masking above should prevent us ever trying
* to take action on an ignored signal other
* than SIGCONT, unless process is traced.
*/
if ((prop & SA_CONT) == 0 &&
(p->p_flag & P_TRACED) == 0)
printf("issignal\n");
break; /* == ignore */
default:
/*
* This signal has an action, let
* postsig() process it.
*/
return (sig);
1994-05-24 10:09:53 +00:00
}
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
sigqueue_delete(&p->p_sigqueue, sig);
1994-05-24 10:09:53 +00:00
}
/* NOTREACHED */
}
void
thread_stopped(struct proc *p)
{
int n;
PROC_LOCK_ASSERT(p, MA_OWNED);
PROC_SLOCK_ASSERT(p, MA_OWNED);
n = p->p_suspcount;
if (p == curproc)
n++;
if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
PROC_SUNLOCK(p);
p->p_flag &= ~P_WAITED;
PROC_LOCK(p->p_pptr);
childproc_stopped(p, (p->p_flag & P_TRACED) ?
CLD_TRAPPED : CLD_STOPPED);
PROC_UNLOCK(p->p_pptr);
PROC_SLOCK(p);
}
}
1994-05-24 10:09:53 +00:00
/*
* Take the action for the specified signal
* from the current set of pending signals.
*/
int
postsig(sig)
register int sig;
1994-05-24 10:09:53 +00:00
{
struct thread *td = curthread;
register struct proc *p = td->td_proc;
struct sigacts *ps;
sig_t action;
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksiginfo_t ksi;
sigset_t returnmask, mask;
1994-05-24 10:09:53 +00:00
KASSERT(sig != 0, ("postsig"));
PROC_LOCK_ASSERT(p, MA_OWNED);
ps = p->p_sigacts;
mtx_assert(&ps->ps_mtx, MA_OWNED);
ksiginfo_init(&ksi);
Currently, when signal is delivered to the process and there is a thread not blocking the signal, signal is placed on the thread sigqueue. If the selected thread is in kernel executing thr_exit() or sigprocmask() syscalls, then signal might be not delivered to usermode for arbitrary amount of time, and for exiting thread it is lost. Put process-directed signals to the process queue unconditionally, selecting the thread to deliver the signal only by the thread returning to usermode, since only then the thread can handle delivery of signal reliably. For exiting thread or thread that has blocked some signals, check whether the newly blocked signal is queued for the process, and try to find a thread to wakeup for delivery, in reschedule_signal(). For exiting thread, assume that all signals are blocked. Change cursig() and postsig() to look both into the thread and process signal queues. When there is a signal that thread returning to usermode could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do unlocked read of p_siglist and p_pendingcnt to check for queued signals. Note that thread that has a signal unblocked might get spurious wakeup and EINTR from the interruptible system call now, due to the possibility of being selected by reschedule_signals(), while other thread returned to usermode earlier and removed the signal from process queue. This should not cause compliance issues, since the thread has not blocked a signal and thus should be ready to receive it anyway. Reported by: Justin Teller <justin.teller gmail com> Reviewed by: davidxu, jilles MFC after: 1 month
2009-10-11 16:49:30 +00:00
if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
return (0);
1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most changes in MD code are trivial, before this change, trapsignal and sendsig use discrete parameters, now they uses member fields of ksiginfo_t structure. For sendsig, this change allows us to pass POSIX realtime signal value to user code. 2. Remove cpu_thread_siginfo, it is no longer needed because we now always generate ksiginfo_t data and feed it to libpthread. 3. Add p_sigqueue to proc structure to hold shared signals which were blocked by all threads in the proc. 4. Add td_sigqueue to thread structure to hold all signals delivered to thread. 5. i386 and amd64 now return POSIX standard si_code, other arches will be fixed. 6. In this sigqueue implementation, pending signal set is kept as before, an extra siginfo list holds additional siginfo_t data for signals. kernel code uses psignal() still behavior as before, it won't be failed even under memory pressure, only exception is when deleting a signal, we should call sigqueue_delete to remove signal from sigqueue but not SIGDELSET. Current there is no kernel code will deliver a signal with additional data, so kernel should be as stable as before, a ksiginfo can carry more information, for example, allow signal to be delivered but throw away siginfo data if memory is not enough. SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can not be caught or masked. The sigqueue() syscall allows user code to queue a signal to target process, if resource is unavailable, EAGAIN will be returned as specification said. Just before thread exits, signal queue memory will be freed by sigqueue_flush. Current, all signals are allowed to be queued, not only realtime signals. Earlier patch reviewed by: jhb, deischen Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
ksi.ksi_signo = sig;
if (ksi.ksi_code == SI_TIMER)
itimer_accept(p, ksi.ksi_timerid, &ksi);
action = ps->ps_sigact[_SIG_IDX(sig)];
1994-05-24 10:09:53 +00:00
#ifdef KTRACE
if (KTRPOINT(td, KTR_PSIG))
ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
&td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
1994-05-24 10:09:53 +00:00
#endif
if (p->p_stops & S_SIG) {
mtx_unlock(&ps->ps_mtx);
stopevent(p, S_SIG, sig);
mtx_lock(&ps->ps_mtx);
}
if (action == SIG_DFL) {
1994-05-24 10:09:53 +00:00
/*
* Default action, where the default is to kill
* the process. (Other cases were ignored above.)
*/
mtx_unlock(&ps->ps_mtx);
sigexit(td, sig);
1994-05-24 10:09:53 +00:00
/* NOTREACHED */
} else {
/*
* If we get here, the signal must be caught.
*/
KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
1999-01-10 01:58:29 +00:00
("postsig action"));
1994-05-24 10:09:53 +00:00
/*
* Set the new mask value and also defer further
* occurrences of this signal.
1994-05-24 10:09:53 +00:00
*
* Special case: user has done a sigsuspend. Here the
1994-05-24 10:09:53 +00:00
* current mask is not of interest, but rather the
* mask from before the sigsuspend is what we want
1994-05-24 10:09:53 +00:00
* restored after the signal processing is completed.
*/
if (td->td_pflags & TDP_OLDMASK) {
returnmask = td->td_oldsigmask;
td->td_pflags &= ~TDP_OLDMASK;
1994-05-24 10:09:53 +00:00
} else
returnmask = td->td_sigmask;
mask = ps->ps_catchmask[_SIG_IDX(sig)];
if (!SIGISMEMBER(ps->ps_signodefer, sig))
SIGADDSET(mask, sig);
kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
if (SIGISMEMBER(ps->ps_sigreset, sig)) {
/*
* See kern_sigaction() for origin of this code.
*/
SIGDELSET(ps->ps_sigcatch, sig);
if (sig != SIGCONT &&
sigprop(sig) & SA_IGNORE)
SIGADDSET(ps->ps_sigignore, sig);
ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
}
td->td_ru.ru_nsignals++;
if (p->p_sig == sig) {
p->p_code = 0;
p->p_sig = 0;
1994-05-24 10:09:53 +00:00
}
(*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
1994-05-24 10:09:53 +00:00
}
return (1);
1994-05-24 10:09:53 +00:00
}
/*
* Kill the current process for stated reason.
*/
void
1994-05-24 10:09:53 +00:00
killproc(p, why)
struct proc *p;
char *why;
{
PROC_LOCK_ASSERT(p, MA_OWNED);
CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)",
p, p->p_pid, p->p_comm);
log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
o Merge contents of struct pcred into struct ucred. Specifically, add the real uid, saved uid, real gid, and saved gid to ucred, as well as the pcred->pc_uidinfo, which was associated with the real uid, only rename it to cr_ruidinfo so as not to conflict with cr_uidinfo, which corresponds to the effective uid. o Remove p_cred from struct proc; add p_ucred to struct proc, replacing original macro that pointed. p->p_ucred to p->p_cred->pc_ucred. o Universally update code so that it makes use of ucred instead of pcred, p->p_ucred instead of p->p_pcred, cr_ruidinfo instead of p_uidinfo, cr_{r,sv}{u,g}id instead of p_*, etc. o Remove pcred0 and its initialization from init_main.c; initialize cr_ruidinfo there. o Restruction many credential modification chunks to always crdup while we figure out locking and optimizations; generally speaking, this means moving to a structure like this: newcred = crdup(oldcred); ... p->p_ucred = newcred; crfree(oldcred); It's not race-free, but better than nothing. There are also races in sys_process.c, all inter-process authorization, fork, exec, and exit. o Remove sigio->sio_ruid since sigio->sio_ucred now contains the ruid; remove comments indicating that the old arrangement was a problem. o Restructure exec1() a little to use newcred/oldcred arrangement, and use improved uid management primitives. o Clean up exit1() so as to do less work in credential cleanup due to pcred removal. o Clean up fork1() so as to do less work in credential cleanup and allocation. o Clean up ktrcanset() to take into account changes, and move to using suser_xxx() instead of performing a direct uid==0 comparision. o Improve commenting in various kern_prot.c credential modification calls to better document current behavior. In a couple of places, current behavior is a little questionable and we need to check POSIX.1 to make sure it's "right". More commenting work still remains to be done. o Update credential management calls, such as crfree(), to take into account new ruidinfo reference. o Modify or add the following uid and gid helper routines: change_euid() change_egid() change_ruid() change_rgid() change_svuid() change_svgid() In each case, the call now acts on a credential not a process, and as such no longer requires more complicated process locking/etc. They now assume the caller will do any necessary allocation of an exclusive credential reference. Each is commented to document its reference requirements. o CANSIGIO() is simplified to require only credentials, not processes and pcreds. o Remove lots of (p_pcred==NULL) checks. o Add an XXX to authorization code in nfs_lock.c, since it's questionable, and needs to be considered carefully. o Simplify posix4 authorization code to require only credentials, not processes and pcreds. Note that this authorization, as well as CANSIGIO(), needs to be updated to use the p_cansignal() and p_cansched() centralized authorization routines, as they currently do not take into account some desirable restrictions that are handled by the centralized routines, as well as being inconsistent with other similar authorization instances. o Update libkvm to take these changes into account. Obtained from: TrustedBSD Project Reviewed by: green, bde, jhb, freebsd-arch, freebsd-audit
2001-05-25 16:59:11 +00:00
p->p_ucred ? p->p_ucred->cr_uid : -1, why);
p->p_flag |= P_WKILLED;
kern_psignal(p, SIGKILL);
1994-05-24 10:09:53 +00:00
}
/*
* Force the current process to exit with the specified signal, dumping core
* if appropriate. We bypass the normal tests for masked and caught signals,
* allowing unrecoverable failures to terminate the process without changing
* signal state. Mark the accounting record with the signal termination.
* If dumping core, save the signal number for the debugger. Calls exit and
* does not return.
*/
void
sigexit(td, sig)
struct thread *td;
int sig;
1994-05-24 10:09:53 +00:00
{
struct proc *p = td->td_proc;
1994-05-24 10:09:53 +00:00
PROC_LOCK_ASSERT(p, MA_OWNED);
1994-05-24 10:09:53 +00:00
p->p_acflag |= AXSIG;
/*
* We must be single-threading to generate a core dump. This
* ensures that the registers in the core file are up-to-date.
* Also, the ELF dump handler assumes that the thread list doesn't
* change out from under it.
*
* XXX If another thread attempts to single-thread before us
* (e.g. via fork()), we won't get a dump at all.
*/
if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
p->p_sig = sig;
/*
* Log signals which would cause core dumps
1995-05-30 08:16:23 +00:00
* (Log as LOG_INFO to appease those who don't want
* these messages.)
* XXX : Todo, as well as euid, write out ruid too
* Note that coredump() drops proc lock.
*/
if (coredump(td) == 0)
sig |= WCOREFLAG;
if (kern_logsigexit)
log(LOG_INFO,
"pid %d (%s), uid %d: exited on signal %d%s\n",
p->p_pid, p->p_comm,
td->td_ucred ? td->td_ucred->cr_uid : -1,
sig &~ WCOREFLAG,
sig & WCOREFLAG ? " (core dumped)" : "");
} else
PROC_UNLOCK(p);
exit1(td, W_EXITCODE(0, sig));
1994-05-24 10:09:53 +00:00
/* NOTREACHED */
}
/*
* Send queued SIGCHLD to parent when child process's state
* is changed.
*/
static void
sigparent(struct proc *p, int reason, int status)
{
PROC_LOCK_ASSERT(p, MA_OWNED);
PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
if (p->p_ksi != NULL) {
p->p_ksi->ksi_signo = SIGCHLD;
p->p_ksi->ksi_code = reason;
p->p_ksi->ksi_status = status;
p->p_ksi->ksi_pid = p->p_pid;
p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
if (KSI_ONQ(p->p_ksi))
return;
}
pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
}
static void
childproc_jobstate(struct proc *p, int reason, int status)
{
struct sigacts *ps;
PROC_LOCK_ASSERT(p, MA_OWNED);
PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
/*
* Wake up parent sleeping in kern_wait(), also send
* SIGCHLD to parent, but SIGCHLD does not guarantee
* that parent will awake, because parent may masked
* the signal.
*/
p->p_pptr->p_flag |= P_STATCHILD;
wakeup(p->p_pptr);
ps = p->p_pptr->p_sigacts;
mtx_lock(&ps->ps_mtx);
if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
mtx_unlock(&ps->ps_mtx);
sigparent(p, reason, status);
} else
mtx_unlock(&ps->ps_mtx);
}
void
childproc_stopped(struct proc *p, int reason)
{
childproc_jobstate(p, reason, p->p_xstat);
}
void
childproc_continued(struct proc *p)
{
childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
}
void
childproc_exited(struct proc *p)
{
int reason;
int status = p->p_xstat; /* convert to int */
reason = CLD_EXITED;
if (WCOREDUMP(status))
reason = CLD_DUMPED;
else if (WIFSIGNALED(status))
reason = CLD_KILLED;
/*
* XXX avoid calling wakeup(p->p_pptr), the work is
* done in exit1().
*/
sigparent(p, reason, status);
}
/*
* We only have 1 character for the core count in the format
* string, so the range will be 0-9
*/
#define MAX_NUM_CORES 10
static int num_cores = 5;
static int
sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
{
int error;
int new_val;
new_val = num_cores;
error = sysctl_handle_int(oidp, &new_val, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
if (new_val > MAX_NUM_CORES)
new_val = MAX_NUM_CORES;
if (new_val < 0)
new_val = 0;
num_cores = new_val;
return (0);
}
SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
#if defined(COMPRESS_USER_CORES)
int compress_user_cores = 1;
SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
&compress_user_cores, 0, "");
int compress_user_cores_gzlevel = -1; /* default level */
SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
&compress_user_cores_gzlevel, -1, "user core gz compression level");
#define GZ_SUFFIX ".gz"
#define GZ_SUFFIX_LEN 3
#endif
static char corefilename[MAXPATHLEN] = {"%N.core"};
SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
sizeof(corefilename), "process corefile name format string");
/*
* expand_name(name, uid, pid, td, compress)
* Expand the name described in corefilename, using name, uid, and pid.
* corefilename is a printf-like string, with three format specifiers:
* %N name of process ("name")
* %P process id (pid)
* %U user id (uid)
* For example, "%N.core" is the default; they can be disabled completely
* by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
* This is controlled by the sysctl variable kern.corefile (see above).
*/
static char *
expand_name(const char *name, uid_t uid, pid_t pid, struct thread *td,
int compress)
{
struct sbuf sb;
const char *format;
char *temp;
size_t i;
int indexpos;
char *hostname;
hostname = NULL;
format = corefilename;
temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
if (temp == NULL)
return (NULL);
indexpos = -1;
(void)sbuf_new(&sb, temp, MAXPATHLEN, SBUF_FIXEDLEN);
for (i = 0; format[i]; i++) {
switch (format[i]) {
case '%': /* Format character */
i++;
switch (format[i]) {
case '%':
sbuf_putc(&sb, '%');
break;
case 'H': /* hostname */
if (hostname == NULL) {
hostname = malloc(MAXHOSTNAMELEN,
M_TEMP, M_NOWAIT);
if (hostname == NULL) {
log(LOG_ERR,
"pid %ld (%s), uid (%lu): "
"unable to alloc memory "
"for corefile hostname\n",
(long)pid, name,
(u_long)uid);
goto nomem;
}
}
getcredhostname(td->td_ucred, hostname,
MAXHOSTNAMELEN);
sbuf_printf(&sb, "%s", hostname);
break;
case 'I': /* autoincrementing index */
sbuf_printf(&sb, "0");
indexpos = sbuf_len(&sb) - 1;
break;
case 'N': /* process name */
sbuf_printf(&sb, "%s", name);
break;
case 'P': /* process id */
sbuf_printf(&sb, "%u", pid);
break;
case 'U': /* user id */
sbuf_printf(&sb, "%u", uid);
break;
default:
log(LOG_ERR,
"Unknown format character %c in "
"corename `%s'\n", format[i], format);
}
break;
default:
sbuf_putc(&sb, format[i]);
}
}
free(hostname, M_TEMP);
#ifdef COMPRESS_USER_CORES
if (compress) {
sbuf_printf(&sb, GZ_SUFFIX);
}
#endif
if (sbuf_error(&sb) != 0) {
log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
"long\n", (long)pid, name, (u_long)uid);
nomem:
sbuf_delete(&sb);
free(temp, M_TEMP);
return (NULL);
}
sbuf_finish(&sb);
sbuf_delete(&sb);
/*
* If the core format has a %I in it, then we need to check
* for existing corefiles before returning a name.
* To do this we iterate over 0..num_cores to find a
* non-existing core file name to use.
*/
if (indexpos != -1) {
struct nameidata nd;
int error, n;
int flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
int cmode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
int vfslocked;
for (n = 0; n < num_cores; n++) {
temp[indexpos] = '0' + n;
NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE,
temp, td);
error = vn_open(&nd, &flags, cmode, NULL);
if (error) {
if (error == EEXIST) {
continue;
}
log(LOG_ERR,
"pid %d (%s), uid (%u): Path `%s' failed "
"on initial open test, error = %d\n",
pid, name, uid, temp, error);
free(temp, M_TEMP);
return (NULL);
}
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
VOP_UNLOCK(nd.ni_vp, 0);
error = vn_close(nd.ni_vp, FWRITE, td->td_ucred, td);
VFS_UNLOCK_GIANT(vfslocked);
if (error) {
log(LOG_ERR,
"pid %d (%s), uid (%u): Path `%s' failed "
"on close after initial open test, "
"error = %d\n",
pid, name, uid, temp, error);
free(temp, M_TEMP);
return (NULL);
}
break;
}
}
return (temp);
}
/*
* Dump a process' core. The main routine does some
* policy checking, and creates the name of the coredump;
* then it passes on a vnode and a size limit to the process-specific
* coredump routine if there is one; if there _is not_ one, it returns
* ENOSYS; otherwise it returns the error from the process-specific routine.
*/
static int
coredump(struct thread *td)
{
struct proc *p = td->td_proc;
register struct vnode *vp;
register struct ucred *cred = td->td_ucred;
struct flock lf;
struct nameidata nd;
struct vattr vattr;
int error, error1, flags, locked;
struct mount *mp;
char *name; /* name of corefile */
off_t limit;
int vfslocked;
int compress;
#ifdef COMPRESS_USER_CORES
compress = compress_user_cores;
#else
compress = 0;
#endif
PROC_LOCK_ASSERT(p, MA_OWNED);
MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
_STOPEVENT(p, S_CORE, 0);
name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid, td,
compress);
if (name == NULL) {
PROC_UNLOCK(p);
#ifdef AUDIT
audit_proc_coredump(td, NULL, EINVAL);
#endif
return (EINVAL);
}
if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) {
PROC_UNLOCK(p);
#ifdef AUDIT
audit_proc_coredump(td, name, EFAULT);
#endif
free(name, M_TEMP);
return (EFAULT);
}
/*
* Note that the bulk of limit checking is done after
* the corefile is created. The exception is if the limit
* for corefiles is 0, in which case we don't bother
* creating the corefile at all. This layout means that
* a corefile is truncated instead of not being created,
* if it is larger than the limit.
*/
Locking for the per-process resource limits structure. - struct plimit includes a mutex to protect a reference count. The plimit structure is treated similarly to struct ucred in that is is always copy on write, so having a reference to a structure is sufficient to read from it without needing a further lock. - The proc lock protects the p_limit pointer and must be held while reading limits from a process to keep the limit structure from changing out from under you while reading from it. - Various global limits that are ints are not protected by a lock since int writes are atomic on all the archs we support and thus a lock wouldn't buy us anything. - All accesses to individual resource limits from a process are abstracted behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return either an rlimit, or the current or max individual limit of the specified resource from a process. - dosetrlimit() was renamed to kern_setrlimit() to match existing style of other similar syscall helper functions. - The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit() (it didn't used the stackgap when it should have) but uses lim_rlimit() and kern_setrlimit() instead. - The svr4 compat no longer uses the stackgap for resource limits calls, but uses lim_rlimit() and kern_setrlimit() instead. - The ibcs2 compat no longer uses the stackgap for resource limits. It also no longer uses the stackgap for accessing sysctl's for the ibcs2_sysconf() syscall but uses kernel_sysctl() instead. As a result, ibcs2_sysconf() no longer needs Giant. - The p_rlimit macro no longer exists. Submitted by: mtm (mostly, I only did a few cleanups and catchups) Tested on: i386 Compiled on: alpha, amd64
2004-02-04 21:52:57 +00:00
limit = (off_t)lim_cur(p, RLIMIT_CORE);
if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
PROC_UNLOCK(p);
#ifdef AUDIT
audit_proc_coredump(td, name, EFBIG);
#endif
free(name, M_TEMP);
Locking for the per-process resource limits structure. - struct plimit includes a mutex to protect a reference count. The plimit structure is treated similarly to struct ucred in that is is always copy on write, so having a reference to a structure is sufficient to read from it without needing a further lock. - The proc lock protects the p_limit pointer and must be held while reading limits from a process to keep the limit structure from changing out from under you while reading from it. - Various global limits that are ints are not protected by a lock since int writes are atomic on all the archs we support and thus a lock wouldn't buy us anything. - All accesses to individual resource limits from a process are abstracted behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return either an rlimit, or the current or max individual limit of the specified resource from a process. - dosetrlimit() was renamed to kern_setrlimit() to match existing style of other similar syscall helper functions. - The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit() (it didn't used the stackgap when it should have) but uses lim_rlimit() and kern_setrlimit() instead. - The svr4 compat no longer uses the stackgap for resource limits calls, but uses lim_rlimit() and kern_setrlimit() instead. - The ibcs2 compat no longer uses the stackgap for resource limits. It also no longer uses the stackgap for accessing sysctl's for the ibcs2_sysconf() syscall but uses kernel_sysctl() instead. As a result, ibcs2_sysconf() no longer needs Giant. - The p_rlimit macro no longer exists. Submitted by: mtm (mostly, I only did a few cleanups and catchups) Tested on: i386 Compiled on: alpha, amd64
2004-02-04 21:52:57 +00:00
return (EFBIG);
}
PROC_UNLOCK(p);
restart:
NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, name, td);
flags = O_CREAT | FWRITE | O_NOFOLLOW;
error = vn_open_cred(&nd, &flags, S_IRUSR | S_IWUSR, VN_OPEN_NOAUDIT,
cred, NULL);
if (error) {
#ifdef AUDIT
audit_proc_coredump(td, name, error);
#endif
free(name, M_TEMP);
return (error);
}
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
vp = nd.ni_vp;
/* Don't dump to non-regular files or files with links. */
if (vp->v_type != VREG ||
VOP_GETATTR(vp, &vattr, cred) || vattr.va_nlink != 1) {
VOP_UNLOCK(vp, 0);
error = EFAULT;
goto close;
}
VOP_UNLOCK(vp, 0);
lf.l_whence = SEEK_SET;
lf.l_start = 0;
lf.l_len = 0;
lf.l_type = F_WRLCK;
locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
lf.l_type = F_UNLCK;
if (locked)
VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
goto out;
if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
goto out;
VFS_UNLOCK_GIANT(vfslocked);
goto restart;
}
VATTR_NULL(&vattr);
vattr.va_size = 0;
if (set_core_nodump_flag)
vattr.va_flags = UF_NODUMP;
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
VOP_SETATTR(vp, &vattr, cred);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
PROC_LOCK(p);
p->p_acflag |= ACORE;
PROC_UNLOCK(p);
error = p->p_sysent->sv_coredump ?
p->p_sysent->sv_coredump(td, vp, limit, compress ? IMGACT_CORE_COMPRESS : 0) :
ENOSYS;
if (locked) {
lf.l_type = F_UNLCK;
VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
}
close:
error1 = vn_close(vp, FWRITE, cred, td);
if (error == 0)
error = error1;
out:
#ifdef AUDIT
audit_proc_coredump(td, name, error);
#endif
free(name, M_TEMP);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
1994-05-24 10:09:53 +00:00
/*
* Nonexistent system call-- signal process (may want to handle it). Flag
* error in case process won't see signal immediately (blocked or ignored).
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct nosys_args {
int dummy;
};
#endif
1994-05-24 10:09:53 +00:00
/* ARGSUSED */
int
nosys(td, args)
struct thread *td;
1994-05-24 10:09:53 +00:00
struct nosys_args *args;
{
struct proc *p = td->td_proc;
PROC_LOCK(p);
tdsignal(td, SIGSYS);
PROC_UNLOCK(p);
return (ENOSYS);
1994-05-24 10:09:53 +00:00
}
/*
* Send a SIGIO or SIGURG signal to a process or process group using stored
* credentials rather than those of the current process.
*/
void
pgsigio(sigiop, sig, checkctty)
struct sigio **sigiop;
int sig, checkctty;
{
ksiginfo_t ksi;
struct sigio *sigio;
ksiginfo_init(&ksi);
ksi.ksi_signo = sig;
ksi.ksi_code = SI_KERNEL;
SIGIO_LOCK();
sigio = *sigiop;
if (sigio == NULL) {
SIGIO_UNLOCK();
return;
}
if (sigio->sio_pgid > 0) {
PROC_LOCK(sigio->sio_proc);
if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
kern_psignal(sigio->sio_proc, sig);
PROC_UNLOCK(sigio->sio_proc);
} else if (sigio->sio_pgid < 0) {
struct proc *p;
PGRP_LOCK(sigio->sio_pgrp);
LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
PROC_LOCK(p);
if (p->p_state == PRS_NORMAL &&
CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
(checkctty == 0 || (p->p_flag & P_CONTROLT)))
kern_psignal(p, sig);
PROC_UNLOCK(p);
}
PGRP_UNLOCK(sigio->sio_pgrp);
}
SIGIO_UNLOCK();
}
static int
filt_sigattach(struct knote *kn)
{
struct proc *p = curproc;
kn->kn_ptr.p_proc = p;
kn->kn_flags |= EV_CLEAR; /* automatically set */
knlist_add(&p->p_klist, kn, 0);
return (0);
}
static void
filt_sigdetach(struct knote *kn)
{
struct proc *p = kn->kn_ptr.p_proc;
knlist_remove(&p->p_klist, kn, 0);
}
/*
* signal knotes are shared with proc knotes, so we apply a mask to
* the hint in order to differentiate them from process hints. This
* could be avoided by using a signal-specific knote list, but probably
* isn't worth the trouble.
*/
static int
filt_signal(struct knote *kn, long hint)
{
if (hint & NOTE_SIGNAL) {
hint &= ~NOTE_SIGNAL;
if (kn->kn_id == hint)
kn->kn_data++;
}
return (kn->kn_data != 0);
}
struct sigacts *
sigacts_alloc(void)
{
struct sigacts *ps;
ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
ps->ps_refcnt = 1;
mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
return (ps);
}
void
sigacts_free(struct sigacts *ps)
{
mtx_lock(&ps->ps_mtx);
ps->ps_refcnt--;
if (ps->ps_refcnt == 0) {
mtx_destroy(&ps->ps_mtx);
free(ps, M_SUBPROC);
} else
mtx_unlock(&ps->ps_mtx);
}
struct sigacts *
sigacts_hold(struct sigacts *ps)
{
mtx_lock(&ps->ps_mtx);
ps->ps_refcnt++;
mtx_unlock(&ps->ps_mtx);
return (ps);
}
void
sigacts_copy(struct sigacts *dest, struct sigacts *src)
{
KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
mtx_lock(&src->ps_mtx);
bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
mtx_unlock(&src->ps_mtx);
}
int
sigacts_shared(struct sigacts *ps)
{
int shared;
mtx_lock(&ps->ps_mtx);
shared = ps->ps_refcnt > 1;
mtx_unlock(&ps->ps_mtx);
return (shared);
}