freebsd-skq/lib/libkse/thread/thr_init.c
David Xu a772047bc6 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

496 lines
15 KiB
C

/*
* Copyright (c) 2003 Daniel M. Eischen <deischen@freebsd.org>
* 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.
*
* $FreeBSD$
*/
/* Allocate space for global thread variables here: */
#define GLOBAL_PTHREAD_PRIVATE
#include "namespace.h"
#include <sys/param.h>
#include <sys/types.h>
#include <sys/signalvar.h>
#include <machine/reg.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/uio.h>
#include <sys/socket.h>
#include <sys/event.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/ttycom.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <pthread.h>
#include <pthread_np.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "un-namespace.h"
#include "libc_private.h"
#include "thr_private.h"
#include "ksd.h"
int __pthread_cond_wait(pthread_cond_t *, pthread_mutex_t *);
int __pthread_mutex_lock(pthread_mutex_t *);
int __pthread_mutex_trylock(pthread_mutex_t *);
void _thread_init_hack(void);
static void init_private(void);
static void init_main_thread(struct pthread *thread);
/*
* All weak references used within libc should be in this table.
* This is so that static libraries will work.
*/
static void *references[] = {
&_accept,
&_bind,
&_close,
&_connect,
&_dup,
&_dup2,
&_execve,
&_fcntl,
&_flock,
&_flockfile,
&_fstat,
&_fstatfs,
&_fsync,
&_funlockfile,
&_getdirentries,
&_getlogin,
&_getpeername,
&_getsockname,
&_getsockopt,
&_ioctl,
&_kevent,
&_listen,
&_nanosleep,
&_open,
&_pthread_getspecific,
&_pthread_key_create,
&_pthread_key_delete,
&_pthread_mutex_destroy,
&_pthread_mutex_init,
&_pthread_mutex_lock,
&_pthread_mutex_trylock,
&_pthread_mutex_unlock,
&_pthread_mutexattr_init,
&_pthread_mutexattr_destroy,
&_pthread_mutexattr_settype,
&_pthread_once,
&_pthread_setspecific,
&_read,
&_readv,
&_recvfrom,
&_recvmsg,
&_select,
&_sendmsg,
&_sendto,
&_setsockopt,
&_sigaction,
&_sigprocmask,
&_sigsuspend,
&_socket,
&_socketpair,
&_thread_init_hack,
&_wait4,
&_write,
&_writev
};
/*
* These are needed when linking statically. All references within
* libgcc (and in the future libc) to these routines are weak, but
* if they are not (strongly) referenced by the application or other
* libraries, then the actual functions will not be loaded.
*/
static void *libgcc_references[] = {
&_pthread_once,
&_pthread_key_create,
&_pthread_key_delete,
&_pthread_getspecific,
&_pthread_setspecific,
&_pthread_mutex_init,
&_pthread_mutex_destroy,
&_pthread_mutex_lock,
&_pthread_mutex_trylock,
&_pthread_mutex_unlock
};
#define DUAL_ENTRY(entry) \
(pthread_func_t)entry, (pthread_func_t)entry
static pthread_func_t jmp_table[][2] = {
{DUAL_ENTRY(_pthread_cond_broadcast)}, /* PJT_COND_BROADCAST */
{DUAL_ENTRY(_pthread_cond_destroy)}, /* PJT_COND_DESTROY */
{DUAL_ENTRY(_pthread_cond_init)}, /* PJT_COND_INIT */
{DUAL_ENTRY(_pthread_cond_signal)}, /* PJT_COND_SIGNAL */
{(pthread_func_t)__pthread_cond_wait,
(pthread_func_t)_pthread_cond_wait}, /* PJT_COND_WAIT */
{DUAL_ENTRY(_pthread_getspecific)}, /* PJT_GETSPECIFIC */
{DUAL_ENTRY(_pthread_key_create)}, /* PJT_KEY_CREATE */
{DUAL_ENTRY(_pthread_key_delete)}, /* PJT_KEY_DELETE*/
{DUAL_ENTRY(_pthread_main_np)}, /* PJT_MAIN_NP */
{DUAL_ENTRY(_pthread_mutex_destroy)}, /* PJT_MUTEX_DESTROY */
{DUAL_ENTRY(_pthread_mutex_init)}, /* PJT_MUTEX_INIT */
{(pthread_func_t)__pthread_mutex_lock,
(pthread_func_t)_pthread_mutex_lock}, /* PJT_MUTEX_LOCK */
{(pthread_func_t)__pthread_mutex_trylock,
(pthread_func_t)_pthread_mutex_trylock},/* PJT_MUTEX_TRYLOCK */
{DUAL_ENTRY(_pthread_mutex_unlock)}, /* PJT_MUTEX_UNLOCK */
{DUAL_ENTRY(_pthread_mutexattr_destroy)}, /* PJT_MUTEXATTR_DESTROY */
{DUAL_ENTRY(_pthread_mutexattr_init)}, /* PJT_MUTEXATTR_INIT */
{DUAL_ENTRY(_pthread_mutexattr_settype)}, /* PJT_MUTEXATTR_SETTYPE */
{DUAL_ENTRY(_pthread_once)}, /* PJT_ONCE */
{DUAL_ENTRY(_pthread_rwlock_destroy)}, /* PJT_RWLOCK_DESTROY */
{DUAL_ENTRY(_pthread_rwlock_init)}, /* PJT_RWLOCK_INIT */
{DUAL_ENTRY(_pthread_rwlock_rdlock)}, /* PJT_RWLOCK_RDLOCK */
{DUAL_ENTRY(_pthread_rwlock_tryrdlock)},/* PJT_RWLOCK_TRYRDLOCK */
{DUAL_ENTRY(_pthread_rwlock_trywrlock)},/* PJT_RWLOCK_TRYWRLOCK */
{DUAL_ENTRY(_pthread_rwlock_unlock)}, /* PJT_RWLOCK_UNLOCK */
{DUAL_ENTRY(_pthread_rwlock_wrlock)}, /* PJT_RWLOCK_WRLOCK */
{DUAL_ENTRY(_pthread_self)}, /* PJT_SELF */
{DUAL_ENTRY(_pthread_setspecific)}, /* PJT_SETSPECIFIC */
{DUAL_ENTRY(_pthread_sigmask)} /* PJT_SIGMASK */
};
static int init_once = 0;
/*
* Threaded process initialization.
*
* This is only called under two conditions:
*
* 1) Some thread routines have detected that the library hasn't yet
* been initialized (_thr_initial == NULL && curthread == NULL), or
*
* 2) An explicit call to reinitialize after a fork (indicated
* by curthread != NULL)
*/
void
_libpthread_init(struct pthread *curthread)
{
int fd;
/* Check if this function has already been called: */
if ((_thr_initial != NULL) && (curthread == NULL))
/* Only initialize the threaded application once. */
return;
/*
* Make gcc quiescent about {,libgcc_}references not being
* referenced:
*/
if ((references[0] == NULL) || (libgcc_references[0] == NULL))
PANIC("Failed loading mandatory references in _thread_init");
/*
* Check the size of the jump table to make sure it is preset
* with the correct number of entries.
*/
if (sizeof(jmp_table) != (sizeof(pthread_func_t) * PJT_MAX * 2))
PANIC("Thread jump table not properly initialized");
memcpy(__thr_jtable, jmp_table, sizeof(jmp_table));
/*
* Check for the special case of this process running as
* or in place of init as pid = 1:
*/
if ((_thr_pid = getpid()) == 1) {
/*
* Setup a new session for this process which is
* assumed to be running as root.
*/
if (setsid() == -1)
PANIC("Can't set session ID");
if (revoke(_PATH_CONSOLE) != 0)
PANIC("Can't revoke console");
if ((fd = __sys_open(_PATH_CONSOLE, O_RDWR)) < 0)
PANIC("Can't open console");
if (setlogin("root") == -1)
PANIC("Can't set login to root");
if (__sys_ioctl(fd, TIOCSCTTY, (char *) NULL) == -1)
PANIC("Can't set controlling terminal");
}
/* Initialize pthread private data. */
init_private();
_kse_init();
/* Initialize the initial kse and kseg. */
_kse_initial = _kse_alloc(NULL);
if (_kse_initial == NULL)
PANIC("Can't allocate initial kse.");
_kse_initial->k_kseg = _kseg_alloc(NULL);
if (_kse_initial->k_kseg == NULL)
PANIC("Can't allocate initial kseg.");
_kse_initial->k_schedq = &_kse_initial->k_kseg->kg_schedq;
TAILQ_INSERT_TAIL(&_kse_initial->k_kseg->kg_kseq, _kse_initial, k_kgqe);
_kse_initial->k_kseg->kg_ksecount = 1;
/* Set the initial thread. */
if (curthread == NULL) {
/* Create and initialize the initial thread. */
curthread = _thr_alloc(NULL);
if (curthread == NULL)
PANIC("Can't allocate initial thread");
_thr_initial = curthread;
init_main_thread(curthread);
} else {
/*
* The initial thread is the current thread. It is
* assumed that the current thread is already initialized
* because it is left over from a fork().
*/
_thr_initial = curthread;
}
_kse_initial->k_kseg->kg_threadcount = 0;
_thr_initial->kse = _kse_initial;
_thr_initial->kseg = _kse_initial->k_kseg;
_thr_initial->active = 1;
/*
* Add the thread to the thread list and to the KSEG's thread
* queue.
*/
THR_LIST_ADD(_thr_initial);
KSEG_THRQ_ADD(_kse_initial->k_kseg, _thr_initial);
/* Setup the KSE/thread specific data for the current KSE/thread. */
if (_ksd_setprivate(&_thr_initial->kse->k_ksd) != 0)
PANIC("Can't set initial KSE specific data");
_set_curkse(_thr_initial->kse);
_thr_initial->kse->k_curthread = _thr_initial;
_thr_initial->kse->k_flags |= KF_INITIALIZED;
_kse_initial->k_curthread = _thr_initial;
_thr_rtld_init();
}
/*
* This function and pthread_create() do a lot of the same things.
* It'd be nice to consolidate the common stuff in one place.
*/
static void
init_main_thread(struct pthread *thread)
{
void *p;
int i;
/* Zero the initial thread structure. */
p = thread->alloc_addr;
memset(thread, 0, sizeof(struct pthread));
thread->alloc_addr = p;
/* Setup the thread attributes. */
thread->attr = _pthread_attr_default;
/*
* Set up the thread stack.
*
* Create a red zone below the main stack. All other stacks
* are constrained to a maximum size by the parameters
* passed to mmap(), but this stack is only limited by
* resource limits, so this stack needs an explicitly mapped
* red zone to protect the thread stack that is just beyond.
*/
if (mmap((void *)_usrstack - THR_STACK_INITIAL -
_thr_guard_default, _thr_guard_default, 0, MAP_ANON,
-1, 0) == MAP_FAILED)
PANIC("Cannot allocate red zone for initial thread");
/*
* Mark the stack as an application supplied stack so that it
* isn't deallocated.
*
* XXX - I'm not sure it would hurt anything to deallocate
* the main thread stack because deallocation doesn't
* actually free() it; it just puts it in the free
* stack queue for later reuse.
*/
thread->attr.stackaddr_attr = (void *)_usrstack - THR_STACK_INITIAL;
thread->attr.stacksize_attr = THR_STACK_INITIAL;
thread->attr.guardsize_attr = _thr_guard_default;
thread->attr.flags |= THR_STACK_USER;
/*
* Write a magic value to the thread structure
* to help identify valid ones:
*/
thread->magic = THR_MAGIC;
thread->slice_usec = -1;
thread->cancelflags = PTHREAD_CANCEL_ENABLE | PTHREAD_CANCEL_DEFERRED;
thread->name = strdup("initial thread");
/* Initialize the thread for signals: */
SIGEMPTYSET(thread->sigmask);
/*
* Set up the thread mailbox. The threads saved context
* is also in the mailbox.
*/
thread->tmbx.tm_udata = thread;
thread->tmbx.tm_context.uc_stack.ss_size = thread->attr.stacksize_attr;
thread->tmbx.tm_context.uc_stack.ss_sp = thread->attr.stackaddr_attr;
/* Default the priority of the initial thread: */
thread->base_priority = THR_DEFAULT_PRIORITY;
thread->active_priority = THR_DEFAULT_PRIORITY;
thread->inherited_priority = 0;
/* Initialize the mutex queue: */
TAILQ_INIT(&thread->mutexq);
/* Initialize thread locking. */
if (_lock_init(&thread->lock, LCK_ADAPTIVE,
_thr_lock_wait, _thr_lock_wakeup) != 0)
PANIC("Cannot initialize initial thread lock");
for (i = 0; i < MAX_THR_LOCKLEVEL; i++) {
_lockuser_init(&thread->lockusers[i], (void *)thread);
_LCK_SET_PRIVATE2(&thread->lockusers[i], (void *)thread);
}
/* Initialize hooks in the thread structure: */
thread->specific = NULL;
thread->cleanup = NULL;
thread->flags = 0;
thread->continuation = NULL;
thread->state = PS_RUNNING;
thread->uniqueid = 0;
}
static void
init_private(void)
{
struct clockinfo clockinfo;
size_t len;
int mib[2];
/*
* Avoid reinitializing some things if they don't need to be,
* e.g. after a fork().
*/
if (init_once == 0) {
/* Find the stack top */
mib[0] = CTL_KERN;
mib[1] = KERN_USRSTACK;
len = sizeof (_usrstack);
if (sysctl(mib, 2, &_usrstack, &len, NULL, 0) == -1)
PANIC("Cannot get kern.usrstack from sysctl");
/*
* Create a red zone below the main stack. All other
* stacks are constrained to a maximum size by the
* parameters passed to mmap(), but this stack is only
* limited by resource limits, so this stack needs an
* explicitly mapped red zone to protect the thread stack
* that is just beyond.
*/
if (mmap((void *)_usrstack - THR_STACK_INITIAL -
_thr_guard_default, _thr_guard_default,
0, MAP_ANON, -1, 0) == MAP_FAILED)
PANIC("Cannot allocate red zone for initial thread");
/* Get the kernel clockrate: */
mib[0] = CTL_KERN;
mib[1] = KERN_CLOCKRATE;
len = sizeof (struct clockinfo);
if (sysctl(mib, 2, &clockinfo, &len, NULL, 0) == 0)
_clock_res_usec = clockinfo.tick;
else
_clock_res_usec = CLOCK_RES_USEC;
_thr_page_size = getpagesize();
_thr_guard_default = _thr_page_size;
init_once = 1; /* Don't do this again. */
} else {
/*
* Destroy the locks before creating them. We don't
* know what state they are in so it is better to just
* recreate them.
*/
_lock_destroy(&_thread_signal_lock);
_lock_destroy(&_mutex_static_lock);
_lock_destroy(&_rwlock_static_lock);
_lock_destroy(&_keytable_lock);
}
/* Initialize everything else. */
TAILQ_INIT(&_thread_list);
TAILQ_INIT(&_thread_gc_list);
/* Initialize the SIG_DFL dummy handler count. */
bzero(_thread_dfl_count, sizeof(_thread_dfl_count));
/*
* Initialize the lock for temporary installation of signal
* handlers (to support sigwait() semantics) and for the
* process signal mask and pending signal sets.
*/
if (_lock_init(&_thread_signal_lock, LCK_ADAPTIVE,
_kse_lock_wait, _kse_lock_wakeup) != 0)
PANIC("Cannot initialize _thread_signal_lock");
if (_lock_init(&_mutex_static_lock, LCK_ADAPTIVE,
_thr_lock_wait, _thr_lock_wakeup) != 0)
PANIC("Cannot initialize mutex static init lock");
if (_lock_init(&_rwlock_static_lock, LCK_ADAPTIVE,
_thr_lock_wait, _thr_lock_wakeup) != 0)
PANIC("Cannot initialize rwlock static init lock");
if (_lock_init(&_keytable_lock, LCK_ADAPTIVE,
_thr_lock_wait, _thr_lock_wakeup) != 0)
PANIC("Cannot initialize thread specific keytable lock");
_thr_spinlock_init();
/* Clear pending signals and get the process signal mask. */
SIGEMPTYSET(_thr_proc_sigpending);
/*
* _thread_list_lock and _kse_count are initialized
* by _kse_init()
*/
}