freebsd-dev/lib/libpthread/thread/thr_sig.c

1251 lines
36 KiB
C
Raw Normal View History

/*
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
* All rights reserved.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 AUTHOR 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.
*
1999-08-28 00:22:10 +00:00
* $FreeBSD$
*/
sigset_t change (part 5 of 5) ----------------------------- Most of the userland changes are in libc. For both the alpha and the i386 setjmp has been changed to accomodate for the new sigset_t. Internally, libc is mostly rewritten to use the new syscalls. The exception is in compat-43/sigcompat.c The POSIX thread library has also been rewritten to use the new sigset_t. Except, that it currently only handles NSIG signals instead of the maximum _SIG_MAXSIG. This should not be a problem because current applications don't use any signals higher than NSIG. There are version bumps for the following libraries: libdialog libreadline libc libc_r libedit libftpio libss These libraries either a) have one of the modified structures visible in the interface, or b) use sigset_t internally and may cause breakage if new binaries are used against libraries that don't have the sigset_t change. This not an immediate issue, but will be as soon as applications start using the new range to its fullest. NOTE: libncurses already had an version bump and has not been given one now. NOTE: doscmd is a real casualty and has been disconnected for the moment. Reconnection will eventually happen after doscmd has been fixed. I'm aware that being the last one to touch it, I'm automaticly promoted to being maintainer. According to good taste this means that I will receive a badge which either will be glued or mechanically stapled, drilled or otherwise violently forced onto me :-) NOTE: pcvt/vttest cannot be compiled with -traditional. The change cause sys/types to be included along the way which contains the const and volatile modifiers. I don't consider this a solution, but more a workaround.
1999-09-29 15:18:46 +00:00
#include <sys/param.h>
#include <sys/types.h>
#include <sys/signalvar.h>
#include <signal.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <pthread.h>
#include "thr_private.h"
/* Prototypes: */
static inline void build_siginfo(siginfo_t *info, int signo);
#ifndef SYSTEM_SCOPE_ONLY
static struct pthread *thr_sig_find(struct kse *curkse, int sig,
siginfo_t *info);
#endif
static inline void thr_sigframe_restore(struct pthread *thread,
struct pthread_sigframe *psf);
static inline void thr_sigframe_save(struct pthread *thread,
struct pthread_sigframe *psf);
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
#define SA_KILL 0x01 /* terminates process by default */
#define SA_STOP 0x02
#define SA_CONT 0x04
static int sigproptbl[NSIG] = {
SA_KILL, /* SIGHUP */
SA_KILL, /* SIGINT */
SA_KILL, /* SIGQUIT */
SA_KILL, /* SIGILL */
SA_KILL, /* SIGTRAP */
SA_KILL, /* SIGABRT */
SA_KILL, /* SIGEMT */
SA_KILL, /* SIGFPE */
SA_KILL, /* SIGKILL */
SA_KILL, /* SIGBUS */
SA_KILL, /* SIGSEGV */
SA_KILL, /* SIGSYS */
SA_KILL, /* SIGPIPE */
SA_KILL, /* SIGALRM */
SA_KILL, /* SIGTERM */
0, /* SIGURG */
SA_STOP, /* SIGSTOP */
SA_STOP, /* SIGTSTP */
SA_CONT, /* SIGCONT */
0, /* SIGCHLD */
SA_STOP, /* SIGTTIN */
SA_STOP, /* SIGTTOU */
0, /* SIGIO */
SA_KILL, /* SIGXCPU */
SA_KILL, /* SIGXFSZ */
SA_KILL, /* SIGVTALRM */
SA_KILL, /* SIGPROF */
0, /* SIGWINCH */
0, /* SIGINFO */
SA_KILL, /* SIGUSR1 */
SA_KILL /* SIGUSR2 */
};
/* #define DEBUG_SIGNAL */
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
#ifdef DEBUG_SIGNAL
#define DBG_MSG stdout_debug
#else
#define DBG_MSG(x...)
#endif
/*
* Signal setup and delivery.
*
* 1) Delivering signals to threads in the same KSE.
* These signals are sent by upcall events and are set in the
* km_sigscaught field of the KSE mailbox. Since these signals
* are received while operating on the KSE stack, they can be
* delivered either by using signalcontext() to add a stack frame
* to the target thread's stack, or by adding them in the thread's
* pending set and having the thread run them down after it
* 2) Delivering signals to threads in other KSEs/KSEGs.
* 3) Delivering signals to threads in critical regions.
* 4) Delivering signals to threads after they change their signal masks.
*
* Methods of delivering signals.
*
* 1) Add a signal frame to the thread's saved context.
* 2) Add the signal to the thread structure, mark the thread as
* having signals to handle, and let the thread run them down
* after it resumes from the KSE scheduler.
*
* Problem with 1). You can't do this to a running thread or a
* thread in a critical region.
*
* Problem with 2). You can't do this to a thread that doesn't
* yield in some way (explicitly enters the scheduler). A thread
* blocked in the kernel or a CPU hungry thread will not see the
* signal without entering the scheduler.
*
* The solution is to use both 1) and 2) to deliver signals:
*
* o Thread in critical region - use 2). When the thread
* leaves the critical region it will check to see if it
* has pending signals and run them down.
*
* o Thread enters scheduler explicitly - use 2). The thread
* can check for pending signals after it returns from the
* the scheduler.
*
* o Thread is running and not current thread - use 2). When the
* thread hits a condition specified by one of the other bullets,
* the signal will be delivered.
*
* o Thread is running and is current thread (e.g., the thread
* has just changed its signal mask and now sees that it has
* pending signals) - just run down the pending signals.
*
* o Thread is swapped out due to quantum expiration - use 1)
*
* o Thread is blocked in kernel - kse_thr_wakeup() and then
* use 1)
*/
/*
* Rules for selecting threads for signals received:
*
* 1) If the signal is a sychronous signal, it is delivered to
* the generating (current thread). If the thread has the
* signal masked, it is added to the threads pending signal
* set until the thread unmasks it.
*
* 2) A thread in sigwait() where the signal is in the thread's
* waitset.
*
* 3) A thread in sigsuspend() where the signal is not in the
* thread's suspended signal mask.
*
* 4) Any thread (first found/easiest to deliver) that has the
* signal unmasked.
*/
#ifndef SYSTEM_SCOPE_ONLY
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
static void *
sig_daemon(void *arg /* Unused */)
{
int i;
kse_critical_t crit;
struct timespec ts;
sigset_t set;
struct kse *curkse;
struct pthread *curthread = _get_curthread();
DBG_MSG("signal daemon started(%p)\n", curthread);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
curthread->name = strdup("signal thread");
crit = _kse_critical_enter();
curkse = _get_curkse();
/*
* Daemon thread is a bound thread and we must be created with
* all signals masked
*/
#if 0
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
SIGFILLSET(set);
__sys_sigprocmask(SIG_SETMASK, &set, NULL);
#endif
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
__sys_sigpending(&set);
ts.tv_sec = 0;
ts.tv_nsec = 0;
while (1) {
KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
_thr_proc_sigpending = set;
KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
for (i = 1; i <= _SIG_MAXSIG; i++) {
if (SIGISMEMBER(set, i) != 0)
_thr_sig_dispatch(curkse, i,
NULL /* no siginfo */);
}
ts.tv_sec = 30;
ts.tv_nsec = 0;
curkse->k_kcb->kcb_kmbx.km_flags =
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
KMF_NOUPCALL | KMF_NOCOMPLETED | KMF_WAITSIGEVENT;
kse_release(&ts);
curkse->k_kcb->kcb_kmbx.km_flags = 0;
set = curkse->k_kcb->kcb_kmbx.km_sigscaught;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
return (0);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* Utility function to create signal daemon thread */
int
_thr_start_sig_daemon(void)
{
pthread_attr_t attr;
sigset_t sigset, oldset;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
SIGFILLSET(sigset);
pthread_sigmask(SIG_SETMASK, &sigset, &oldset);
pthread_attr_init(&attr);
pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM);
attr->flags |= THR_SIGNAL_THREAD;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* sigmask will be inherited */
if (pthread_create(&_thr_sig_daemon, &attr, sig_daemon, NULL))
PANIC("can not create signal daemon thread!\n");
pthread_attr_destroy(&attr);
pthread_sigmask(SIG_SETMASK, &oldset, NULL);
return (0);
}
/*
* This signal handler only delivers asynchronous signals.
* This must be called with upcalls disabled and without
* holding any locks.
*/
void
_thr_sig_dispatch(struct kse *curkse, int sig, siginfo_t *info)
{
struct kse_mailbox *kmbx;
struct pthread *thread;
DBG_MSG(">>> _thr_sig_dispatch(%d)\n", sig);
/* Check if the signal requires a dump of thread information: */
if (sig == SIGINFO) {
/* Dump thread information to file: */
_thread_dump_info();
}
while ((thread = thr_sig_find(curkse, sig, info)) != NULL) {
/*
* Setup the target thread to receive the signal:
*/
DBG_MSG("Got signal %d, selecting thread %p\n", sig, thread);
KSE_SCHED_LOCK(curkse, thread->kseg);
if ((thread->state == PS_DEAD) ||
(thread->state == PS_DEADLOCK) ||
THR_IS_EXITING(thread) || THR_IS_SUSPENDED(thread)) {
KSE_SCHED_UNLOCK(curkse, thread->kseg);
_thr_ref_delete(NULL, thread);
} else if (SIGISMEMBER(thread->sigmask, sig)) {
KSE_SCHED_UNLOCK(curkse, thread->kseg);
_thr_ref_delete(NULL, thread);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
} else {
kmbx = _thr_sig_add(thread, sig, info);
KSE_SCHED_UNLOCK(curkse, thread->kseg);
_thr_ref_delete(NULL, thread);
if (kmbx != NULL)
kse_wakeup(kmbx);
break;
}
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
DBG_MSG("<<< _thr_sig_dispatch\n");
}
#endif /* ! SYSTEM_SCOPE_ONLY */
static __inline int
sigprop(int sig)
{
if (sig > 0 && sig < NSIG)
return (sigproptbl[_SIG_IDX(sig)]);
return (0);
}
typedef void (*ohandler)(int sig, int code,
struct sigcontext *scp, char *addr, __sighandler_t *catcher);
void
_thr_sig_handler(int sig, siginfo_t *info, ucontext_t *ucp)
{
struct pthread_sigframe psf;
__siginfohandler_t *sigfunc;
struct pthread *curthread;
struct kse *curkse;
struct sigaction act;
int sa_flags, err_save;
err_save = errno;
DBG_MSG(">>> _thr_sig_handler(%d)\n", sig);
curthread = _get_curthread();
if (curthread == NULL)
PANIC("No current thread.\n");
if (!(curthread->attr.flags & PTHREAD_SCOPE_SYSTEM))
PANIC("Thread is not system scope.\n");
if (curthread->flags & THR_FLAGS_EXITING) {
errno = err_save;
return;
}
curkse = _get_curkse();
/*
* If thread is in critical region or if thread is on
* the way of state transition, then latch signal into buffer.
*/
if (_kse_in_critical() || THR_IN_CRITICAL(curthread) ||
curthread->state != PS_RUNNING) {
DBG_MSG(">>> _thr_sig_handler(%d) in critical\n", sig);
curthread->siginfo[sig-1] = *info;
curthread->check_pending = 1;
curkse->k_sigseqno++;
SIGADDSET(curthread->sigpend, sig);
/*
* If the kse is on the way to idle itself, but
* we have signal ready, we should prevent it
* to sleep, kernel will latch the wakeup request,
* so kse_release will return from kernel immediately.
*/
if (KSE_IS_IDLE(curkse))
kse_wakeup(&curkse->k_kcb->kcb_kmbx);
errno = err_save;
return;
}
/* Check if the signal requires a dump of thread information: */
if (sig == SIGINFO) {
/* Dump thread information to file: */
_thread_dump_info();
}
/* Check the threads previous state: */
curthread->critical_count++;
if (curthread->sigbackout != NULL)
curthread->sigbackout((void *)curthread);
curthread->critical_count--;
thr_sigframe_save(curthread, &psf);
THR_ASSERT(!(curthread->sigbackout), "sigbackout was not cleared.");
_kse_critical_enter();
/* Get a fresh copy of signal mask */
__sys_sigprocmask(SIG_BLOCK, NULL, &curthread->sigmask);
KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
sigfunc = _thread_sigact[sig - 1].sa_sigaction;
2003-12-28 12:20:04 +00:00
sa_flags = _thread_sigact[sig - 1].sa_flags;
if (sa_flags & SA_RESETHAND) {
act.sa_handler = SIG_DFL;
act.sa_flags = SA_RESTART;
SIGEMPTYSET(act.sa_mask);
__sys_sigaction(sig, &act, NULL);
__sys_sigaction(sig, NULL, &_thread_sigact[sig - 1]);
}
KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
_kse_critical_leave(&curthread->tcb->tcb_tmbx);
/* Now invoke real handler */
if (((__sighandler_t *)sigfunc != SIG_DFL) &&
((__sighandler_t *)sigfunc != SIG_IGN) &&
(sigfunc != (__siginfohandler_t *)_thr_sig_handler)) {
if ((sa_flags & SA_SIGINFO) != 0 || info == NULL)
(*(sigfunc))(sig, info, ucp);
else {
((ohandler)(*sigfunc))(
sig, info->si_code, (struct sigcontext *)ucp,
info->si_addr, (__sighandler_t *)sigfunc);
}
} else {
if ((__sighandler_t *)sigfunc == SIG_DFL) {
if (sigprop(sig) & SA_KILL) {
if (_kse_isthreaded())
kse_thr_interrupt(NULL,
KSE_INTR_SIGEXIT, sig);
else
kill(getpid(), sig);
}
#ifdef NOTYET
else if (sigprop(sig) & SA_STOP)
kse_thr_interrupt(NULL, KSE_INTR_JOBSTOP, sig);
#endif
}
}
_kse_critical_enter();
curthread->sigmask = ucp->uc_sigmask;
SIG_CANTMASK(curthread->sigmask);
_kse_critical_leave(&curthread->tcb->tcb_tmbx);
thr_sigframe_restore(curthread, &psf);
DBG_MSG("<<< _thr_sig_handler(%d)\n", sig);
errno = err_save;
}
struct sighandle_info {
__siginfohandler_t *sigfunc;
int sa_flags;
int sig;
siginfo_t *info;
ucontext_t *ucp;
};
static void handle_signal(struct pthread *curthread,
struct sighandle_info *shi);
static void handle_signal_altstack(struct pthread *curthread,
struct sighandle_info *shi);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* Must be called with signal lock and schedule lock held in order */
static void
thr_sig_invoke_handler(struct pthread *curthread, int sig, siginfo_t *info,
ucontext_t *ucp)
{
__siginfohandler_t *sigfunc;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
sigset_t sigmask;
int sa_flags;
int onstack;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
struct sigaction act;
struct kse *curkse;
struct sighandle_info shi;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/*
* Invoke the signal handler without going through the scheduler:
*/
DBG_MSG("Got signal %d, calling handler for current thread %p\n",
sig, curthread);
In the words of the author: o The polling mechanism for I/O readiness was changed from select() to poll(). In additon, a wrapped version of poll() is now provided. o The wrapped select routine now converts each fd_set to a poll array so that the thread scheduler doesn't have to perform a bitwise search for selected fds each time file descriptors are polled for I/O readiness. o The thread scheduler was modified to use a new queue (_workq) for threads that need work. Threads waiting for I/O readiness and spinblocks are added to the work queue in addition to the waiting queue. This reduces the time spent forming/searching the array of file descriptors being polled. o The waiting queue (_waitingq) is now maintained in order of thread wakeup time. This allows the thread scheduler to find the nearest wakeup time by looking at the first thread in the queue instead of searching the entire queue. o Removed file descriptor locking for select/poll routines. An application should not rely on the threads library for providing this locking; if necessary, the application should use mutexes to protect selecting/polling of file descriptors. o Retrieve and use the kernel clock rate/resolution at startup instead of hardcoding the clock resolution to 10 msec (tested with kernel running at 1000 HZ). o All queues have been changed to use queue.h macros. These include the queues of all threads, dead threads, and threads waiting for file descriptor locks. o Added reinitialization of the GC mutex and condition variable after a fork. Also prevented reallocation of the ready queue after a fork. o Prevented the wrapped close routine from closing the thread kernel pipes. o Initialized file descriptor table for stdio entries at thread init. o Provided additional flags to indicate to what queues threads belong. o Moved TAILQ initialization for statically allocated mutex and condition variables to after the spinlock. o Added dispatching of signals to pthread_kill. Removing the dispatching of signals from thread activation broke sigsuspend when pthread_kill was used to send a signal to a thread. o Temporarily set the state of a thread to PS_SUSPENDED when it is first created and placed in the list of threads so that it will not be accidentally scheduled before becoming a member of one of the scheduling queues. o Change the signal handler to queue signals to the thread kernel pipe if the scheduling queues are protected. When scheduling queues are unprotected, signals are then dequeued and handled. o Ensured that all installed signal handlers block the scheduling signal and that the scheduling signal handler blocks all other signals. This ensures that the signal handler is only interruptible for and by non-scheduling signals. An atomic lock is used to decide which instance of the signal handler will handle pending signals. o Removed _lock_thread_list and _unlock_thread_list as they are no longer used to protect the thread list. o Added missing RCS IDs to modified files. o Added checks for appropriate queue membership and activity when adding, removing, and searching the scheduling queues. These checks add very little overhead and are enabled when compiled with _PTHREADS_INVARIANTS defined. Suggested and implemented by Tor Egge with some modification by me. o Close a race condition in uthread_close. (Tor Egge) o Protect the scheduling queues while modifying them in pthread_cond_signal and _thread_fd_unlock. (Tor Egge) o Ensure that when a thread gets a mutex, the mutex is on that threads list of owned mutexes. (Tor Egge) o Set the kernel-in-scheduler flag in _thread_kern_sched_state and _thread_kern_sched_state_unlock to prevent a scheduling signal from calling the scheduler again. (Tor Egge) o Don't use TAILQ_FOREACH macro while searching the waiting queue for threads in a sigwait state, because a change of state destroys the TAILQ link. It is actually safe to do so, though, because once a sigwaiting thread is found, the loop ends and the function returns. (Tor Egge) o When dispatching signals to threads, make the thread inherit the signal deferral flag of the currently running thread. (Tor Egge) Submitted by: Daniel Eischen <eischen@vigrid.com> and Tor Egge <Tor.Egge@fast.no>
1999-06-20 08:28:48 +00:00
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (!_kse_in_critical())
PANIC("thr_sig_invoke_handler without in critical\n");
curkse = curthread->kse;
/*
* Check that a custom handler is installed and if
* the signal is not blocked:
*/
sigfunc = _thread_sigact[sig - 1].sa_sigaction;
2003-12-28 12:20:04 +00:00
sa_flags = _thread_sigact[sig - 1].sa_flags;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
sigmask = curthread->sigmask;
SIGSETOR(curthread->sigmask, _thread_sigact[sig - 1].sa_mask);
if (!(sa_flags & (SA_NODEFER | SA_RESETHAND)))
SIGADDSET(curthread->sigmask, sig);
if ((sig != SIGILL) && (sa_flags & SA_RESETHAND)) {
act.sa_handler = SIG_DFL;
act.sa_flags = SA_RESTART;
SIGEMPTYSET(act.sa_mask);
__sys_sigaction(sig, &act, NULL);
__sys_sigaction(sig, NULL, &_thread_sigact[sig - 1]);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
KSE_SCHED_UNLOCK(curkse, curkse->k_kseg);
/*
* We are processing buffered signals, synchronize working
* signal mask into kernel.
*/
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
__sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL);
onstack = _thr_sigonstack(&sigfunc);
ucp->uc_stack = curthread->sigstk;
ucp->uc_stack.ss_flags = (curthread->sigstk.ss_flags & SS_DISABLE)
? SS_DISABLE : ((onstack) ? SS_ONSTACK : 0);
if (curthread->oldsigmask) {
ucp->uc_sigmask = *(curthread->oldsigmask);
curthread->oldsigmask = NULL;
} else
ucp->uc_sigmask = sigmask;
shi.sigfunc = sigfunc;
shi.sig = sig;
2004-01-02 00:27:30 +00:00
shi.sa_flags = sa_flags;
shi.info = info;
shi.ucp = ucp;
if ((curthread->sigstk.ss_flags & SS_DISABLE) == 0) {
/* Deliver signal on alternative stack */
if (sa_flags & SA_ONSTACK && !onstack)
handle_signal_altstack(curthread, &shi);
else
handle_signal(curthread, &shi);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
} else {
handle_signal(curthread, &shi);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
_kse_critical_enter();
/* Don't trust after critical leave/enter */
curkse = curthread->kse;
/*
* Restore the thread's signal mask.
*/
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
curthread->sigmask = ucp->uc_sigmask;
SIG_CANTMASK(curthread->sigmask);
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
__sys_sigprocmask(SIG_SETMASK, &ucp->uc_sigmask, NULL);
KSE_SCHED_LOCK(curkse, curkse->k_kseg);
KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
DBG_MSG("Got signal %d, handler returned %p\n", sig, curthread);
}
static void
handle_signal(struct pthread *curthread, struct sighandle_info *shi)
{
_kse_critical_leave(&curthread->tcb->tcb_tmbx);
/* Check if the signal requires a dump of thread information: */
if (shi->sig == SIGINFO) {
/* Dump thread information to file: */
_thread_dump_info();
}
if (((__sighandler_t *)shi->sigfunc != SIG_DFL) &&
((__sighandler_t *)shi->sigfunc != SIG_IGN)) {
if ((shi->sa_flags & SA_SIGINFO) != 0 || shi->info == NULL)
(*(shi->sigfunc))(shi->sig, shi->info, shi->ucp);
else {
((ohandler)(*shi->sigfunc))(
shi->sig, shi->info->si_code,
(struct sigcontext *)shi->ucp,
shi->info->si_addr,
(__sighandler_t *)shi->sigfunc);
}
} else {
if ((__sighandler_t *)shi->sigfunc == SIG_DFL) {
if (sigprop(shi->sig) & SA_KILL) {
if (_kse_isthreaded())
kse_thr_interrupt(NULL,
KSE_INTR_SIGEXIT, shi->sig);
else
kill(getpid(), shi->sig);
}
#ifdef NOTYET
else if (sigprop(shi->sig) & SA_STOP)
kse_thr_interrupt(NULL, KSE_INTR_JOBSTOP,
shi->sig);
#endif
}
}
}
static void
handle_signal_wrapper(struct pthread *curthread, ucontext_t *ret_uc,
struct sighandle_info *shi)
{
shi->ucp->uc_stack.ss_flags = SS_ONSTACK;
handle_signal(curthread, shi);
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
setcontext(ret_uc);
else {
/* Work around for ia64, THR_SETCONTEXT does not work */
_kse_critical_enter();
curthread->tcb->tcb_tmbx.tm_context = *ret_uc;
_thread_switch(curthread->kse->k_kcb, curthread->tcb, 1);
/* THR_SETCONTEXT */
}
}
/*
* Jump to stack set by sigaltstack before invoking signal handler
*/
static void
handle_signal_altstack(struct pthread *curthread, struct sighandle_info *shi)
{
volatile int once;
ucontext_t uc1, *uc2;
THR_ASSERT(_kse_in_critical(), "Not in critical");
once = 0;
THR_GETCONTEXT(&uc1);
if (once == 0) {
once = 1;
/* XXX
* We are still in critical region, it is safe to operate thread
* context
*/
uc2 = &curthread->tcb->tcb_tmbx.tm_context;
uc2->uc_stack = curthread->sigstk;
makecontext(uc2, (void (*)(void))handle_signal_wrapper,
3, curthread, &uc1, shi);
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
setcontext(uc2);
else {
_thread_switch(curthread->kse->k_kcb, curthread->tcb, 1);
/* THR_SETCONTEXT(uc2); */
}
}
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
int
_thr_getprocsig(int sig, siginfo_t *siginfo)
{
kse_critical_t crit;
struct kse *curkse;
int ret;
DBG_MSG(">>> _thr_getprocsig\n");
crit = _kse_critical_enter();
curkse = _get_curkse();
KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
ret = _thr_getprocsig_unlocked(sig, siginfo);
KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
_kse_critical_leave(crit);
DBG_MSG("<<< _thr_getprocsig\n");
return (ret);
}
int
_thr_getprocsig_unlocked(int sig, siginfo_t *siginfo)
{
sigset_t sigset;
struct timespec ts;
/* try to retrieve signal from kernel */
SIGEMPTYSET(sigset);
SIGADDSET(sigset, sig);
ts.tv_sec = 0;
ts.tv_nsec = 0;
SIGDELSET(_thr_proc_sigpending, sig);
if (__sys_sigtimedwait(&sigset, siginfo, &ts) > 0)
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
return (sig);
return (0);
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
}
#ifndef SYSTEM_SCOPE_ONLY
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
/*
* Find a thread that can handle the signal. This must be called
* with upcalls disabled.
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
*/
struct pthread *
thr_sig_find(struct kse *curkse, int sig, siginfo_t *info)
In the words of the author: o The polling mechanism for I/O readiness was changed from select() to poll(). In additon, a wrapped version of poll() is now provided. o The wrapped select routine now converts each fd_set to a poll array so that the thread scheduler doesn't have to perform a bitwise search for selected fds each time file descriptors are polled for I/O readiness. o The thread scheduler was modified to use a new queue (_workq) for threads that need work. Threads waiting for I/O readiness and spinblocks are added to the work queue in addition to the waiting queue. This reduces the time spent forming/searching the array of file descriptors being polled. o The waiting queue (_waitingq) is now maintained in order of thread wakeup time. This allows the thread scheduler to find the nearest wakeup time by looking at the first thread in the queue instead of searching the entire queue. o Removed file descriptor locking for select/poll routines. An application should not rely on the threads library for providing this locking; if necessary, the application should use mutexes to protect selecting/polling of file descriptors. o Retrieve and use the kernel clock rate/resolution at startup instead of hardcoding the clock resolution to 10 msec (tested with kernel running at 1000 HZ). o All queues have been changed to use queue.h macros. These include the queues of all threads, dead threads, and threads waiting for file descriptor locks. o Added reinitialization of the GC mutex and condition variable after a fork. Also prevented reallocation of the ready queue after a fork. o Prevented the wrapped close routine from closing the thread kernel pipes. o Initialized file descriptor table for stdio entries at thread init. o Provided additional flags to indicate to what queues threads belong. o Moved TAILQ initialization for statically allocated mutex and condition variables to after the spinlock. o Added dispatching of signals to pthread_kill. Removing the dispatching of signals from thread activation broke sigsuspend when pthread_kill was used to send a signal to a thread. o Temporarily set the state of a thread to PS_SUSPENDED when it is first created and placed in the list of threads so that it will not be accidentally scheduled before becoming a member of one of the scheduling queues. o Change the signal handler to queue signals to the thread kernel pipe if the scheduling queues are protected. When scheduling queues are unprotected, signals are then dequeued and handled. o Ensured that all installed signal handlers block the scheduling signal and that the scheduling signal handler blocks all other signals. This ensures that the signal handler is only interruptible for and by non-scheduling signals. An atomic lock is used to decide which instance of the signal handler will handle pending signals. o Removed _lock_thread_list and _unlock_thread_list as they are no longer used to protect the thread list. o Added missing RCS IDs to modified files. o Added checks for appropriate queue membership and activity when adding, removing, and searching the scheduling queues. These checks add very little overhead and are enabled when compiled with _PTHREADS_INVARIANTS defined. Suggested and implemented by Tor Egge with some modification by me. o Close a race condition in uthread_close. (Tor Egge) o Protect the scheduling queues while modifying them in pthread_cond_signal and _thread_fd_unlock. (Tor Egge) o Ensure that when a thread gets a mutex, the mutex is on that threads list of owned mutexes. (Tor Egge) o Set the kernel-in-scheduler flag in _thread_kern_sched_state and _thread_kern_sched_state_unlock to prevent a scheduling signal from calling the scheduler again. (Tor Egge) o Don't use TAILQ_FOREACH macro while searching the waiting queue for threads in a sigwait state, because a change of state destroys the TAILQ link. It is actually safe to do so, though, because once a sigwaiting thread is found, the loop ends and the function returns. (Tor Egge) o When dispatching signals to threads, make the thread inherit the signal deferral flag of the currently running thread. (Tor Egge) Submitted by: Daniel Eischen <eischen@vigrid.com> and Tor Egge <Tor.Egge@fast.no>
1999-06-20 08:28:48 +00:00
{
struct kse_mailbox *kmbx = NULL;
struct pthread *pthread;
struct pthread *suspended_thread, *signaled_thread;
__siginfohandler_t *sigfunc;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
siginfo_t si;
In the words of the author: o The polling mechanism for I/O readiness was changed from select() to poll(). In additon, a wrapped version of poll() is now provided. o The wrapped select routine now converts each fd_set to a poll array so that the thread scheduler doesn't have to perform a bitwise search for selected fds each time file descriptors are polled for I/O readiness. o The thread scheduler was modified to use a new queue (_workq) for threads that need work. Threads waiting for I/O readiness and spinblocks are added to the work queue in addition to the waiting queue. This reduces the time spent forming/searching the array of file descriptors being polled. o The waiting queue (_waitingq) is now maintained in order of thread wakeup time. This allows the thread scheduler to find the nearest wakeup time by looking at the first thread in the queue instead of searching the entire queue. o Removed file descriptor locking for select/poll routines. An application should not rely on the threads library for providing this locking; if necessary, the application should use mutexes to protect selecting/polling of file descriptors. o Retrieve and use the kernel clock rate/resolution at startup instead of hardcoding the clock resolution to 10 msec (tested with kernel running at 1000 HZ). o All queues have been changed to use queue.h macros. These include the queues of all threads, dead threads, and threads waiting for file descriptor locks. o Added reinitialization of the GC mutex and condition variable after a fork. Also prevented reallocation of the ready queue after a fork. o Prevented the wrapped close routine from closing the thread kernel pipes. o Initialized file descriptor table for stdio entries at thread init. o Provided additional flags to indicate to what queues threads belong. o Moved TAILQ initialization for statically allocated mutex and condition variables to after the spinlock. o Added dispatching of signals to pthread_kill. Removing the dispatching of signals from thread activation broke sigsuspend when pthread_kill was used to send a signal to a thread. o Temporarily set the state of a thread to PS_SUSPENDED when it is first created and placed in the list of threads so that it will not be accidentally scheduled before becoming a member of one of the scheduling queues. o Change the signal handler to queue signals to the thread kernel pipe if the scheduling queues are protected. When scheduling queues are unprotected, signals are then dequeued and handled. o Ensured that all installed signal handlers block the scheduling signal and that the scheduling signal handler blocks all other signals. This ensures that the signal handler is only interruptible for and by non-scheduling signals. An atomic lock is used to decide which instance of the signal handler will handle pending signals. o Removed _lock_thread_list and _unlock_thread_list as they are no longer used to protect the thread list. o Added missing RCS IDs to modified files. o Added checks for appropriate queue membership and activity when adding, removing, and searching the scheduling queues. These checks add very little overhead and are enabled when compiled with _PTHREADS_INVARIANTS defined. Suggested and implemented by Tor Egge with some modification by me. o Close a race condition in uthread_close. (Tor Egge) o Protect the scheduling queues while modifying them in pthread_cond_signal and _thread_fd_unlock. (Tor Egge) o Ensure that when a thread gets a mutex, the mutex is on that threads list of owned mutexes. (Tor Egge) o Set the kernel-in-scheduler flag in _thread_kern_sched_state and _thread_kern_sched_state_unlock to prevent a scheduling signal from calling the scheduler again. (Tor Egge) o Don't use TAILQ_FOREACH macro while searching the waiting queue for threads in a sigwait state, because a change of state destroys the TAILQ link. It is actually safe to do so, though, because once a sigwaiting thread is found, the loop ends and the function returns. (Tor Egge) o When dispatching signals to threads, make the thread inherit the signal deferral flag of the currently running thread. (Tor Egge) Submitted by: Daniel Eischen <eischen@vigrid.com> and Tor Egge <Tor.Egge@fast.no>
1999-06-20 08:28:48 +00:00
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
DBG_MSG("Looking for thread to handle signal %d\n", sig);
/*
* Enter a loop to look for threads that have the signal
* unmasked. POSIX specifies that a thread in a sigwait
* will get the signal over any other threads. Second
* preference will be threads in in a sigsuspend. Third
* preference will be the current thread. If none of the
* above, then the signal is delivered to the first thread
* that is found. Note that if a custom handler is not
* installed, the signal only affects threads in sigwait.
*/
suspended_thread = NULL;
signaled_thread = NULL;
KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
TAILQ_FOREACH(pthread, &_thread_list, tle) {
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (pthread == _thr_sig_daemon)
continue;
/* Signal delivering to bound thread is done by kernel */
if (pthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
continue;
/* Take the scheduling lock. */
KSE_SCHED_LOCK(curkse, pthread->kseg);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if ((pthread->state == PS_DEAD) ||
(pthread->state == PS_DEADLOCK) ||
THR_IS_EXITING(pthread) ||
THR_IS_SUSPENDED(pthread)) {
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
; /* Skip this thread. */
} else if (pthread->state == PS_SIGWAIT &&
SIGISMEMBER(*(pthread->data.sigwait->waitset), sig)) {
In the words of the author: o The polling mechanism for I/O readiness was changed from select() to poll(). In additon, a wrapped version of poll() is now provided. o The wrapped select routine now converts each fd_set to a poll array so that the thread scheduler doesn't have to perform a bitwise search for selected fds each time file descriptors are polled for I/O readiness. o The thread scheduler was modified to use a new queue (_workq) for threads that need work. Threads waiting for I/O readiness and spinblocks are added to the work queue in addition to the waiting queue. This reduces the time spent forming/searching the array of file descriptors being polled. o The waiting queue (_waitingq) is now maintained in order of thread wakeup time. This allows the thread scheduler to find the nearest wakeup time by looking at the first thread in the queue instead of searching the entire queue. o Removed file descriptor locking for select/poll routines. An application should not rely on the threads library for providing this locking; if necessary, the application should use mutexes to protect selecting/polling of file descriptors. o Retrieve and use the kernel clock rate/resolution at startup instead of hardcoding the clock resolution to 10 msec (tested with kernel running at 1000 HZ). o All queues have been changed to use queue.h macros. These include the queues of all threads, dead threads, and threads waiting for file descriptor locks. o Added reinitialization of the GC mutex and condition variable after a fork. Also prevented reallocation of the ready queue after a fork. o Prevented the wrapped close routine from closing the thread kernel pipes. o Initialized file descriptor table for stdio entries at thread init. o Provided additional flags to indicate to what queues threads belong. o Moved TAILQ initialization for statically allocated mutex and condition variables to after the spinlock. o Added dispatching of signals to pthread_kill. Removing the dispatching of signals from thread activation broke sigsuspend when pthread_kill was used to send a signal to a thread. o Temporarily set the state of a thread to PS_SUSPENDED when it is first created and placed in the list of threads so that it will not be accidentally scheduled before becoming a member of one of the scheduling queues. o Change the signal handler to queue signals to the thread kernel pipe if the scheduling queues are protected. When scheduling queues are unprotected, signals are then dequeued and handled. o Ensured that all installed signal handlers block the scheduling signal and that the scheduling signal handler blocks all other signals. This ensures that the signal handler is only interruptible for and by non-scheduling signals. An atomic lock is used to decide which instance of the signal handler will handle pending signals. o Removed _lock_thread_list and _unlock_thread_list as they are no longer used to protect the thread list. o Added missing RCS IDs to modified files. o Added checks for appropriate queue membership and activity when adding, removing, and searching the scheduling queues. These checks add very little overhead and are enabled when compiled with _PTHREADS_INVARIANTS defined. Suggested and implemented by Tor Egge with some modification by me. o Close a race condition in uthread_close. (Tor Egge) o Protect the scheduling queues while modifying them in pthread_cond_signal and _thread_fd_unlock. (Tor Egge) o Ensure that when a thread gets a mutex, the mutex is on that threads list of owned mutexes. (Tor Egge) o Set the kernel-in-scheduler flag in _thread_kern_sched_state and _thread_kern_sched_state_unlock to prevent a scheduling signal from calling the scheduler again. (Tor Egge) o Don't use TAILQ_FOREACH macro while searching the waiting queue for threads in a sigwait state, because a change of state destroys the TAILQ link. It is actually safe to do so, though, because once a sigwaiting thread is found, the loop ends and the function returns. (Tor Egge) o When dispatching signals to threads, make the thread inherit the signal deferral flag of the currently running thread. (Tor Egge) Submitted by: Daniel Eischen <eischen@vigrid.com> and Tor Egge <Tor.Egge@fast.no>
1999-06-20 08:28:48 +00:00
/*
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
* retrieve signal from kernel, if it is job control
* signal, and sigaction is SIG_DFL, then we will
* be stopped in kernel, we hold lock here, but that
* does not matter, because that's job control, and
* whole process should be stopped.
In the words of the author: o The polling mechanism for I/O readiness was changed from select() to poll(). In additon, a wrapped version of poll() is now provided. o The wrapped select routine now converts each fd_set to a poll array so that the thread scheduler doesn't have to perform a bitwise search for selected fds each time file descriptors are polled for I/O readiness. o The thread scheduler was modified to use a new queue (_workq) for threads that need work. Threads waiting for I/O readiness and spinblocks are added to the work queue in addition to the waiting queue. This reduces the time spent forming/searching the array of file descriptors being polled. o The waiting queue (_waitingq) is now maintained in order of thread wakeup time. This allows the thread scheduler to find the nearest wakeup time by looking at the first thread in the queue instead of searching the entire queue. o Removed file descriptor locking for select/poll routines. An application should not rely on the threads library for providing this locking; if necessary, the application should use mutexes to protect selecting/polling of file descriptors. o Retrieve and use the kernel clock rate/resolution at startup instead of hardcoding the clock resolution to 10 msec (tested with kernel running at 1000 HZ). o All queues have been changed to use queue.h macros. These include the queues of all threads, dead threads, and threads waiting for file descriptor locks. o Added reinitialization of the GC mutex and condition variable after a fork. Also prevented reallocation of the ready queue after a fork. o Prevented the wrapped close routine from closing the thread kernel pipes. o Initialized file descriptor table for stdio entries at thread init. o Provided additional flags to indicate to what queues threads belong. o Moved TAILQ initialization for statically allocated mutex and condition variables to after the spinlock. o Added dispatching of signals to pthread_kill. Removing the dispatching of signals from thread activation broke sigsuspend when pthread_kill was used to send a signal to a thread. o Temporarily set the state of a thread to PS_SUSPENDED when it is first created and placed in the list of threads so that it will not be accidentally scheduled before becoming a member of one of the scheduling queues. o Change the signal handler to queue signals to the thread kernel pipe if the scheduling queues are protected. When scheduling queues are unprotected, signals are then dequeued and handled. o Ensured that all installed signal handlers block the scheduling signal and that the scheduling signal handler blocks all other signals. This ensures that the signal handler is only interruptible for and by non-scheduling signals. An atomic lock is used to decide which instance of the signal handler will handle pending signals. o Removed _lock_thread_list and _unlock_thread_list as they are no longer used to protect the thread list. o Added missing RCS IDs to modified files. o Added checks for appropriate queue membership and activity when adding, removing, and searching the scheduling queues. These checks add very little overhead and are enabled when compiled with _PTHREADS_INVARIANTS defined. Suggested and implemented by Tor Egge with some modification by me. o Close a race condition in uthread_close. (Tor Egge) o Protect the scheduling queues while modifying them in pthread_cond_signal and _thread_fd_unlock. (Tor Egge) o Ensure that when a thread gets a mutex, the mutex is on that threads list of owned mutexes. (Tor Egge) o Set the kernel-in-scheduler flag in _thread_kern_sched_state and _thread_kern_sched_state_unlock to prevent a scheduling signal from calling the scheduler again. (Tor Egge) o Don't use TAILQ_FOREACH macro while searching the waiting queue for threads in a sigwait state, because a change of state destroys the TAILQ link. It is actually safe to do so, though, because once a sigwaiting thread is found, the loop ends and the function returns. (Tor Egge) o When dispatching signals to threads, make the thread inherit the signal deferral flag of the currently running thread. (Tor Egge) Submitted by: Daniel Eischen <eischen@vigrid.com> and Tor Egge <Tor.Egge@fast.no>
1999-06-20 08:28:48 +00:00
*/
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (_thr_getprocsig(sig, &si)) {
DBG_MSG("Waking thread %p in sigwait"
" with signal %d\n", pthread, sig);
/* where to put siginfo ? */
*(pthread->data.sigwait->siginfo) = si;
kmbx = _thr_setrunnable_unlocked(pthread);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
KSE_SCHED_UNLOCK(curkse, pthread->kseg);
/*
* POSIX doesn't doesn't specify which thread
* will get the signal if there are multiple
* waiters, so we give it to the first thread
* we find.
*
* Do not attempt to deliver this signal
* to other threads and do not add the signal
* to the process pending set.
*/
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
if (kmbx != NULL)
kse_wakeup(kmbx);
if (suspended_thread != NULL)
_thr_ref_delete(NULL, suspended_thread);
if (signaled_thread != NULL)
_thr_ref_delete(NULL, signaled_thread);
return (NULL);
} else if (!SIGISMEMBER(pthread->sigmask, sig)) {
/*
* If debugger is running, we don't quick exit,
* and give it a chance to check the signal.
*/
if (_libkse_debug == 0) {
sigfunc = _thread_sigact[sig - 1].sa_sigaction;
if ((__sighandler_t *)sigfunc == SIG_DFL) {
if (sigprop(sig) & SA_KILL) {
kse_thr_interrupt(NULL,
KSE_INTR_SIGEXIT, sig);
/* Never reach */
}
}
}
if (pthread->state == PS_SIGSUSPEND) {
if (suspended_thread == NULL) {
suspended_thread = pthread;
suspended_thread->refcount++;
}
} else if (signaled_thread == NULL) {
signaled_thread = pthread;
signaled_thread->refcount++;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
}
KSE_SCHED_UNLOCK(curkse, pthread->kseg);
}
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (suspended_thread != NULL) {
pthread = suspended_thread;
if (signaled_thread)
_thr_ref_delete(NULL, signaled_thread);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
} else if (signaled_thread) {
pthread = signaled_thread;
} else {
pthread = NULL;
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
return (pthread);
}
#endif /* ! SYSTEM_SCOPE_ONLY */
static inline void
build_siginfo(siginfo_t *info, int signo)
{
bzero(info, sizeof(*info));
info->si_signo = signo;
info->si_pid = _thr_pid;
}
/*
* This is called by a thread when it has pending signals to deliver.
* It should only be called from the context of the thread.
*/
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
void
_thr_sig_rundown(struct pthread *curthread, ucontext_t *ucp)
{
struct pthread_sigframe psf;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
siginfo_t siginfo;
int i, err_save;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
kse_critical_t crit;
struct kse *curkse;
sigset_t sigmask;
err_save = errno;
DBG_MSG(">>> thr_sig_rundown (%p)\n", curthread);
/* Check the threads previous state: */
curthread->critical_count++;
if (curthread->sigbackout != NULL)
curthread->sigbackout((void *)curthread);
curthread->critical_count--;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
THR_ASSERT(!(curthread->sigbackout), "sigbackout was not cleared.");
THR_ASSERT((curthread->state == PS_RUNNING), "state is not PS_RUNNING");
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
thr_sigframe_save(curthread, &psf);
/*
* Lower the priority before calling the handler in case
* it never returns (longjmps back):
*/
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
crit = _kse_critical_enter();
curkse = curthread->kse;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
KSE_SCHED_LOCK(curkse, curkse->k_kseg);
KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
curthread->active_priority &= ~THR_SIGNAL_PRIORITY;
SIGFILLSET(sigmask);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
while (1) {
/*
* For bound thread, we mask all signals and get a fresh
* copy of signal mask from kernel
*/
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
__sys_sigprocmask(SIG_SETMASK, &sigmask,
&curthread->sigmask);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
for (i = 1; i <= _SIG_MAXSIG; i++) {
if (SIGISMEMBER(curthread->sigmask, i))
continue;
if (SIGISMEMBER(curthread->sigpend, i)) {
SIGDELSET(curthread->sigpend, i);
siginfo = curthread->siginfo[i-1];
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
break;
}
if (!(curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
&& SIGISMEMBER(_thr_proc_sigpending, i)) {
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (_thr_getprocsig_unlocked(i, &siginfo))
break;
}
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (i <= _SIG_MAXSIG)
thr_sig_invoke_handler(curthread, i, &siginfo, ucp);
else {
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
__sys_sigprocmask(SIG_SETMASK,
&curthread->sigmask, NULL);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
break;
}
}
/* Don't trust after signal handling */
curkse = curthread->kse;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
KSE_SCHED_UNLOCK(curkse, curkse->k_kseg);
_kse_critical_leave(&curthread->tcb->tcb_tmbx);
/* repost masked signal to kernel, it hardly happens in real world */
if ((curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) &&
!SIGISEMPTY(curthread->sigpend)) { /* dirty read */
__sys_sigprocmask(SIG_SETMASK, &sigmask, &curthread->sigmask);
for (i = 1; i <= _SIG_MAXSIG; ++i) {
if (SIGISMEMBER(curthread->sigpend, i)) {
SIGDELSET(curthread->sigpend, i);
if (!_kse_isthreaded())
kill(getpid(), i);
else
kse_thr_interrupt(
&curthread->tcb->tcb_tmbx,
KSE_INTR_SENDSIG,
i);
}
}
__sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL);
}
DBG_MSG("<<< thr_sig_rundown (%p)\n", curthread);
thr_sigframe_restore(curthread, &psf);
errno = err_save;
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
}
/*
* This checks pending signals for the current thread. It should be
* called whenever a thread changes its signal mask. Note that this
* is called from a thread (using its stack).
*
* XXX - We might want to just check to see if there are pending
* signals for the thread here, but enter the UTS scheduler
* to actually install the signal handler(s).
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
*/
void
_thr_sig_check_pending(struct pthread *curthread)
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
{
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
ucontext_t uc;
volatile int once;
int errsave;
/*
* If the thread is in critical region, delay processing signals.
* If the thread state is not PS_RUNNING, it might be switching
* into UTS and but a THR_LOCK_RELEASE saw check_pending, and it
* goes here, in the case we delay processing signals, lets UTS
* process complicated things, normally UTS will call _thr_sig_add
* to resume the thread, so we needn't repeat doing it here.
*/
if (THR_IN_CRITICAL(curthread) || curthread->state != PS_RUNNING)
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
return;
errsave = errno;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
once = 0;
THR_GETCONTEXT(&uc);
if (once == 0) {
once = 1;
curthread->check_pending = 0;
_thr_sig_rundown(curthread, &uc);
}
errno = errsave;
}
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
/*
* Perform thread specific actions in response to a signal.
* This function is only called if there is a handler installed
* for the signal, and if the target thread has the signal
* unmasked.
*
* This must be called with the thread's scheduling lock held.
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
*/
struct kse_mailbox *
_thr_sig_add(struct pthread *pthread, int sig, siginfo_t *info)
{
siginfo_t siginfo;
struct kse *curkse;
struct kse_mailbox *kmbx = NULL;
struct pthread *curthread = _get_curthread();
int restart;
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
int suppress_handler = 0;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
int fromproc = 0;
__sighandler_t *sigfunc;
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
DBG_MSG(">>> _thr_sig_add %p (%d)\n", pthread, sig);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
curkse = _get_curkse();
restart = _thread_sigact[sig - 1].sa_flags & SA_RESTART;
sigfunc = _thread_sigact[sig - 1].sa_handler;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
fromproc = (curthread == _thr_sig_daemon);
if (pthread->state == PS_DEAD || pthread->state == PS_DEADLOCK ||
pthread->state == PS_STATE_MAX)
return (NULL); /* return false */
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if ((pthread->attr.flags & PTHREAD_SCOPE_SYSTEM) &&
(curthread != pthread)) {
PANIC("Please use _thr_send_sig for bound thread");
return (NULL);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
if (pthread->state != PS_SIGWAIT &&
SIGISMEMBER(pthread->sigmask, sig)) {
/* signal is masked, just add signal to thread. */
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (!fromproc) {
SIGADDSET(pthread->sigpend, sig);
if (info == NULL)
build_siginfo(&pthread->siginfo[sig-1], sig);
else if (info != &pthread->siginfo[sig-1])
memcpy(&pthread->siginfo[sig-1], info,
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
sizeof(*info));
} else {
if (!_thr_getprocsig(sig, &pthread->siginfo[sig-1]))
return (NULL);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
SIGADDSET(pthread->sigpend, sig);
}
}
else {
/* if process signal not exists, just return */
if (fromproc) {
if (!_thr_getprocsig(sig, &siginfo))
return (NULL);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
info = &siginfo;
}
if (pthread->state != PS_SIGWAIT && sigfunc == SIG_DFL &&
(sigprop(sig) & SA_KILL)) {
kse_thr_interrupt(NULL, KSE_INTR_SIGEXIT, sig);
/* Never reach */
}
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
/*
* Process according to thread state:
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
*/
switch (pthread->state) {
case PS_DEAD:
case PS_DEADLOCK:
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
case PS_STATE_MAX:
return (NULL); /* XXX return false */
case PS_LOCKWAIT:
case PS_SUSPENDED:
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
/*
* You can't call a signal handler for threads in these
* states.
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
*/
suppress_handler = 1;
break;
case PS_RUNNING:
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if ((pthread->flags & THR_FLAGS_IN_RUNQ)) {
THR_RUNQ_REMOVE(pthread);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
pthread->active_priority |= THR_SIGNAL_PRIORITY;
THR_RUNQ_INSERT_TAIL(pthread);
} else {
/* Possible not in RUNQ and has curframe ? */
pthread->active_priority |= THR_SIGNAL_PRIORITY;
}
break;
/*
* States which cannot be interrupted but still require the
* signal handler to run:
*/
case PS_COND_WAIT:
case PS_MUTEX_WAIT:
break;
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
case PS_SLEEP_WAIT:
/*
* Unmasked signals always cause sleep to terminate
* early regardless of SA_RESTART:
*/
pthread->interrupted = 1;
break;
case PS_JOIN:
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
break;
case PS_SIGSUSPEND:
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
pthread->interrupted = 1;
break;
case PS_SIGWAIT:
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
if (info == NULL)
build_siginfo(&pthread->siginfo[sig-1], sig);
else if (info != &pthread->siginfo[sig-1])
memcpy(&pthread->siginfo[sig-1], info,
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
sizeof(*info));
/*
* The signal handler is not called for threads in
* SIGWAIT.
*/
suppress_handler = 1;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* Wake up the thread if the signal is not blocked. */
if (SIGISMEMBER(*(pthread->data.sigwait->waitset), sig)) {
/* Return the signal number: */
*(pthread->data.sigwait->siginfo) = pthread->siginfo[sig-1];
/* Make the thread runnable: */
kmbx = _thr_setrunnable_unlocked(pthread);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
} else {
/* Increment the pending signal count. */
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
SIGADDSET(pthread->sigpend, sig);
if (!SIGISMEMBER(pthread->sigmask, sig)) {
if (sigfunc == SIG_DFL &&
sigprop(sig) & SA_KILL) {
kse_thr_interrupt(NULL,
KSE_INTR_SIGEXIT,
sig);
/* Never reach */
}
pthread->check_pending = 1;
pthread->interrupted = 1;
kmbx = _thr_setrunnable_unlocked(pthread);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
return (kmbx);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
SIGADDSET(pthread->sigpend, sig);
if (info == NULL)
build_siginfo(&pthread->siginfo[sig-1], sig);
else if (info != &pthread->siginfo[sig-1])
memcpy(&pthread->siginfo[sig-1], info, sizeof(*info));
pthread->check_pending = 1;
if (!(pthread->attr.flags & PTHREAD_SCOPE_SYSTEM) &&
(pthread->blocked != 0) && !THR_IN_CRITICAL(pthread))
kse_thr_interrupt(&pthread->tcb->tcb_tmbx,
restart ? KSE_INTR_RESTART : KSE_INTR_INTERRUPT, 0);
if (suppress_handler == 0) {
/*
* Setup a signal frame and save the current threads
* state:
*/
if (pthread->state != PS_RUNNING) {
if (pthread->flags & THR_FLAGS_IN_RUNQ)
THR_RUNQ_REMOVE(pthread);
pthread->active_priority |= THR_SIGNAL_PRIORITY;
kmbx = _thr_setrunnable_unlocked(pthread);
}
}
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
}
return (kmbx);
}
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
/*
* Send a signal to a specific thread (ala pthread_kill):
*/
void
_thr_sig_send(struct pthread *pthread, int sig)
{
struct pthread *curthread = _get_curthread();
struct kse_mailbox *kmbx;
if (pthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
kse_thr_interrupt(&pthread->tcb->tcb_tmbx, KSE_INTR_SENDSIG, sig);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
return;
}
/* Lock the scheduling queue of the target thread. */
THR_SCHED_LOCK(curthread, pthread);
if (_thread_sigact[sig - 1].sa_handler != SIG_IGN) {
kmbx = _thr_sig_add(pthread, sig, NULL);
/* Add a preemption point. */
if (kmbx == NULL && (curthread->kseg == pthread->kseg) &&
(pthread->active_priority > curthread->active_priority))
curthread->critical_yield = 1;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
THR_SCHED_UNLOCK(curthread, pthread);
if (kmbx != NULL)
kse_wakeup(kmbx);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* XXX
* If thread sent signal to itself, check signals now.
* It is not really needed, _kse_critical_leave should
* have already checked signals.
*/
if (pthread == curthread && curthread->check_pending)
_thr_sig_check_pending(curthread);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
} else {
THR_SCHED_UNLOCK(curthread, pthread);
}
}
static inline void
thr_sigframe_restore(struct pthread *curthread, struct pthread_sigframe *psf)
{
kse_critical_t crit;
struct kse *curkse;
THR_THREAD_LOCK(curthread, curthread);
curthread->cancelflags = psf->psf_cancelflags;
crit = _kse_critical_enter();
curkse = curthread->kse;
KSE_SCHED_LOCK(curkse, curthread->kseg);
curthread->flags = psf->psf_flags;
curthread->interrupted = psf->psf_interrupted;
curthread->timeout = psf->psf_timeout;
curthread->data = psf->psf_wait_data;
curthread->wakeup_time = psf->psf_wakeup_time;
curthread->continuation = psf->psf_continuation;
KSE_SCHED_UNLOCK(curkse, curthread->kseg);
_kse_critical_leave(crit);
THR_THREAD_UNLOCK(curthread, curthread);
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
}
static inline void
thr_sigframe_save(struct pthread *curthread, struct pthread_sigframe *psf)
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
{
kse_critical_t crit;
struct kse *curkse;
Implement zero system call thread switching. Performance of thread switches should be on par with that under scheduler activations. o Timing is achieved through the use of a fixed interval timer (ITIMER_PROF) to count scheduling ticks instead of retrieving the time-of-day upon every thread switch and calculating elapsed real time. o Polling for I/O readiness is performed once for each scheduling tick instead of every thread switch. o The non-signal saving/restoring versions of setjmp/longjmp are used to save and restore thread contexts. This may allow the removal of _THREAD_SAFE macros from setjmp() and longjmp() - needs more investigation. Change signal handling so that signals are handled in the context of the thread that is receiving the signal. When signals are dispatched to a thread, a special signal handling frame is created on top of the target threads stack. The frame contains the threads saved state information and a new context in which the thread can run. The applications signal handler is invoked through a wrapper routine that knows how to restore the threads saved state and unwind to previous frames. Fix interruption of threads due to signals. Some states were being improperly interrupted while other states were not being interrupted. This should fix several PRs. Signal handlers, which are invoked as a result of a process signal (not by pthread_kill()), are now called with the code (or siginfo_t if SA_SIGINFO was set in sa_flags) and sigcontext_t as received from the process signal handler. Modify the search for a thread to which a signal is delivered. The search algorithm is now: o First thread found in sigwait() with signal in wait mask. o First thread found sigsuspend()'d on the signal. o Current thread if signal is unmasked. o First thread found with signal unmasked. Collapse machine dependent support into macros defined in pthread_private.h. These should probably eventually be moved into separate MD files. Change the range of settable priorities to be compliant with POSIX (0-31). The threads library uses higher priorities internally for real-time threads (not yet implemented) and threads executing signal handlers. Real-time threads and threads running signal handlers add 64 and 32, respectively, to a threads base priority. Some other small changes and cleanups. PR: 17757 18559 21943 Reviewed by: jasone
2000-10-13 22:12:32 +00:00
THR_THREAD_LOCK(curthread, curthread);
psf->psf_cancelflags = curthread->cancelflags;
crit = _kse_critical_enter();
curkse = curthread->kse;
KSE_SCHED_LOCK(curkse, curthread->kseg);
/* This has to initialize all members of the sigframe. */
psf->psf_flags = (curthread->flags & (THR_FLAGS_PRIVATE | THR_FLAGS_EXITING));
psf->psf_interrupted = curthread->interrupted;
psf->psf_timeout = curthread->timeout;
psf->psf_wait_data = curthread->data;
psf->psf_wakeup_time = curthread->wakeup_time;
psf->psf_continuation = curthread->continuation;
KSE_SCHED_UNLOCK(curkse, curthread->kseg);
_kse_critical_leave(crit);
THR_THREAD_UNLOCK(curthread, curthread);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
void
_thr_signal_init(void)
{
struct sigaction act;
__siginfohandler_t *sigfunc;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
int i;
sigset_t sigset;
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
SIGFILLSET(sigset);
__sys_sigprocmask(SIG_SETMASK, &sigset, &_thr_initial->sigmask);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* Enter a loop to get the existing signal status: */
for (i = 1; i <= _SIG_MAXSIG; i++) {
/* Get the signal handler details: */
if (__sys_sigaction(i, NULL, &_thread_sigact[i - 1]) != 0) {
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/*
* Abort this process if signal
* initialisation fails:
*/
PANIC("Cannot read signal handler info");
}
/* Intall wrapper if handler was set */
sigfunc = _thread_sigact[i - 1].sa_sigaction;
if (((__sighandler_t *)sigfunc) != SIG_DFL &&
((__sighandler_t *)sigfunc) != SIG_IGN) {
act = _thread_sigact[i - 1];
act.sa_flags |= SA_SIGINFO;
act.sa_sigaction =
(__siginfohandler_t *)_thr_sig_handler;
__sys_sigaction(i, &act, NULL);
}
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
/*
* Install the signal handler for SIGINFO. It isn't
* really needed, but it is nice to have for debugging
* purposes.
*/
_thread_sigact[SIGINFO - 1].sa_flags = SA_SIGINFO | SA_RESTART;
SIGEMPTYSET(act.sa_mask);
act.sa_flags = SA_SIGINFO | SA_RESTART;
act.sa_sigaction = (__siginfohandler_t *)&_thr_sig_handler;
if (__sys_sigaction(SIGINFO, &act, NULL) != 0) {
__sys_sigprocmask(SIG_SETMASK, &_thr_initial->sigmask, NULL);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/*
* Abort this process if signal initialisation fails:
*/
PANIC("Cannot initialize signal handler");
}
__sys_sigprocmask(SIG_SETMASK, &_thr_initial->sigmask, NULL);
__sys_sigaltstack(NULL, &_thr_initial->sigstk);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}
void
_thr_signal_deinit(void)
{
int i;
struct pthread *curthread = _get_curthread();
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* Clear process pending signals. */
sigemptyset(&_thr_proc_sigpending);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/* Enter a loop to get the existing signal status: */
for (i = 1; i <= _SIG_MAXSIG; i++) {
/* Check for signals which cannot be trapped: */
if (i == SIGKILL || i == SIGSTOP) {
}
/* Set the signal handler details: */
else if (__sys_sigaction(i, &_thread_sigact[i - 1],
NULL) != 0) {
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
/*
* Abort this process if signal
* initialisation fails:
*/
PANIC("Cannot set signal handler info");
}
}
__sys_sigaltstack(&curthread->sigstk, NULL);
o Use a daemon thread to monitor signal events in kernel, if pending signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
2003-06-28 09:55:02 +00:00
}