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9bf4d6404e
2000-04-24 Ulrich Drepper <drepper@redhat.com> * manager.c (pthread_free): Use FREE_THREAD not FREE_THREAD_SELF. * sysdeps/i386/useldt.h: Use "q" constraint instead of "r" where necessary. * sysdeps/i386/i686/pt-machine.h: Include "../useldt.h".
705 lines
24 KiB
C
705 lines
24 KiB
C
/* Linuxthreads - a simple clone()-based implementation of Posix */
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/* threads for Linux. */
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/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
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/* */
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/* This program is free software; you can redistribute it and/or */
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/* modify it under the terms of the GNU Library General Public License */
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/* as published by the Free Software Foundation; either version 2 */
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/* of the License, or (at your option) any later version. */
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/* */
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/* This program is distributed in the hope that it will be useful, */
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/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
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/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */
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/* GNU Library General Public License for more details. */
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/* The "thread manager" thread: manages creation and termination of threads */
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#include <errno.h>
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#include <sched.h>
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#include <stddef.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include <sys/poll.h> /* for poll */
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#include <sys/mman.h> /* for mmap */
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#include <sys/param.h>
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#include <sys/time.h>
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#include <sys/wait.h> /* for waitpid macros */
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#include "pthread.h"
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#include "internals.h"
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#include "spinlock.h"
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#include "restart.h"
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#include "semaphore.h"
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/* Array of active threads. Entry 0 is reserved for the initial thread. */
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struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX] =
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{ { LOCK_INITIALIZER, &__pthread_initial_thread, 0},
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{ LOCK_INITIALIZER, &__pthread_manager_thread, 0}, /* All NULLs */ };
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/* For debugging purposes put the maximum number of threads in a variable. */
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const int __linuxthreads_pthread_threads_max = PTHREAD_THREADS_MAX;
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/* Indicate whether at least one thread has a user-defined stack (if 1),
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or if all threads have stacks supplied by LinuxThreads (if 0). */
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int __pthread_nonstandard_stacks;
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/* Number of active entries in __pthread_handles (used by gdb) */
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volatile int __pthread_handles_num = 2;
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/* Whether to use debugger additional actions for thread creation
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(set to 1 by gdb) */
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volatile int __pthread_threads_debug;
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/* Globally enabled events. */
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volatile td_thr_events_t __pthread_threads_events;
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/* Pointer to thread descriptor with last event. */
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volatile pthread_descr __pthread_last_event;
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/* Mapping from stack segment to thread descriptor. */
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/* Stack segment numbers are also indices into the __pthread_handles array. */
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/* Stack segment number 0 is reserved for the initial thread. */
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static inline pthread_descr thread_segment(int seg)
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{
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return (pthread_descr)(THREAD_STACK_START_ADDRESS - (seg - 1) * STACK_SIZE)
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- 1;
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}
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/* Flag set in signal handler to record child termination */
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static volatile int terminated_children = 0;
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/* Flag set when the initial thread is blocked on pthread_exit waiting
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for all other threads to terminate */
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static int main_thread_exiting = 0;
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/* Counter used to generate unique thread identifier.
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Thread identifier is pthread_threads_counter + segment. */
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static pthread_t pthread_threads_counter = 0;
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/* Forward declarations */
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static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
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void * (*start_routine)(void *), void *arg,
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sigset_t *mask, int father_pid,
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int report_events,
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td_thr_events_t *event_maskp);
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static void pthread_handle_free(pthread_t th_id);
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static void pthread_handle_exit(pthread_descr issuing_thread, int exitcode);
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static void pthread_reap_children(void);
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static void pthread_kill_all_threads(int sig, int main_thread_also);
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/* The server thread managing requests for thread creation and termination */
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int __pthread_manager(void *arg)
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{
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int reqfd = (int) (long int) arg;
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struct pollfd ufd;
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sigset_t mask;
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int n;
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struct pthread_request request;
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/* If we have special thread_self processing, initialize it. */
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#ifdef INIT_THREAD_SELF
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INIT_THREAD_SELF(&__pthread_manager_thread, 1);
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#endif
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/* Set the error variable. */
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__pthread_manager_thread.p_errnop = &__pthread_manager_thread.p_errno;
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__pthread_manager_thread.p_h_errnop = &__pthread_manager_thread.p_h_errno;
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/* Block all signals except __pthread_sig_cancel and SIGTRAP */
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sigfillset(&mask);
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sigdelset(&mask, __pthread_sig_cancel); /* for thread termination */
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sigdelset(&mask, SIGTRAP); /* for debugging purposes */
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if (__pthread_threads_debug && __pthread_sig_debug > 0)
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sigdelset(&mask, __pthread_sig_debug);
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sigprocmask(SIG_SETMASK, &mask, NULL);
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/* Raise our priority to match that of main thread */
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__pthread_manager_adjust_prio(__pthread_main_thread->p_priority);
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/* Synchronize debugging of the thread manager */
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n = __libc_read(reqfd, (char *)&request, sizeof(request));
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ASSERT(n == sizeof(request) && request.req_kind == REQ_DEBUG);
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ufd.fd = reqfd;
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ufd.events = POLLIN;
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/* Enter server loop */
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while(1) {
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n = __poll(&ufd, 1, 2000);
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/* Check for termination of the main thread */
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if (getppid() == 1) {
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pthread_kill_all_threads(SIGKILL, 0);
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_exit(0);
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}
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/* Check for dead children */
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if (terminated_children) {
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terminated_children = 0;
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pthread_reap_children();
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}
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/* Read and execute request */
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if (n == 1 && (ufd.revents & POLLIN)) {
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n = __libc_read(reqfd, (char *)&request, sizeof(request));
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ASSERT(n == sizeof(request));
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switch(request.req_kind) {
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case REQ_CREATE:
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request.req_thread->p_retcode =
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pthread_handle_create((pthread_t *) &request.req_thread->p_retval,
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request.req_args.create.attr,
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request.req_args.create.fn,
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request.req_args.create.arg,
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&request.req_args.create.mask,
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request.req_thread->p_pid,
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request.req_thread->p_report_events,
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&request.req_thread->p_eventbuf.eventmask);
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restart(request.req_thread);
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break;
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case REQ_FREE:
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pthread_handle_free(request.req_args.free.thread_id);
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break;
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case REQ_PROCESS_EXIT:
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pthread_handle_exit(request.req_thread,
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request.req_args.exit.code);
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break;
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case REQ_MAIN_THREAD_EXIT:
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main_thread_exiting = 1;
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if (__pthread_main_thread->p_nextlive == __pthread_main_thread) {
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restart(__pthread_main_thread);
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return 0;
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}
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break;
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case REQ_POST:
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__new_sem_post(request.req_args.post);
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break;
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case REQ_DEBUG:
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/* Make gdb aware of new thread and gdb will restart the
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new thread when it is ready to handle the new thread. */
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if (__pthread_threads_debug && __pthread_sig_debug > 0)
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raise(__pthread_sig_debug);
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break;
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}
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}
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}
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}
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int __pthread_manager_event(void *arg)
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{
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/* If we have special thread_self processing, initialize it. */
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#ifdef INIT_THREAD_SELF
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INIT_THREAD_SELF(&__pthread_manager_thread, 1);
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#endif
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/* Get the lock the manager will free once all is correctly set up. */
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__pthread_lock (THREAD_GETMEM((&__pthread_manager_thread), p_lock), NULL);
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/* Free it immediately. */
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__pthread_spin_unlock (THREAD_GETMEM((&__pthread_manager_thread), p_lock));
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return __pthread_manager(arg);
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}
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/* Process creation */
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static int pthread_start_thread(void *arg)
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{
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pthread_descr self = (pthread_descr) arg;
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struct pthread_request request;
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void * outcome;
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/* Initialize special thread_self processing, if any. */
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#ifdef INIT_THREAD_SELF
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INIT_THREAD_SELF(self, self->p_nr);
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#endif
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/* Make sure our pid field is initialized, just in case we get there
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before our father has initialized it. */
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THREAD_SETMEM(self, p_pid, __getpid());
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/* Initial signal mask is that of the creating thread. (Otherwise,
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we'd just inherit the mask of the thread manager.) */
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sigprocmask(SIG_SETMASK, &self->p_start_args.mask, NULL);
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/* Set the scheduling policy and priority for the new thread, if needed */
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if (THREAD_GETMEM(self, p_start_args.schedpolicy) >= 0)
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/* Explicit scheduling attributes were provided: apply them */
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__sched_setscheduler(THREAD_GETMEM(self, p_pid),
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THREAD_GETMEM(self, p_start_args.schedpolicy),
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&self->p_start_args.schedparam);
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else if (__pthread_manager_thread.p_priority > 0)
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/* Default scheduling required, but thread manager runs in realtime
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scheduling: switch new thread to SCHED_OTHER policy */
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{
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struct sched_param default_params;
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default_params.sched_priority = 0;
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__sched_setscheduler(THREAD_GETMEM(self, p_pid),
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SCHED_OTHER, &default_params);
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}
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/* Make gdb aware of new thread */
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if (__pthread_threads_debug && __pthread_sig_debug > 0) {
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request.req_thread = self;
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request.req_kind = REQ_DEBUG;
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__libc_write(__pthread_manager_request,
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(char *) &request, sizeof(request));
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suspend(self);
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}
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/* Run the thread code */
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outcome = self->p_start_args.start_routine(THREAD_GETMEM(self,
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p_start_args.arg));
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/* Exit with the given return value */
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pthread_exit(outcome);
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return 0;
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}
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static int pthread_start_thread_event(void *arg)
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{
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pthread_descr self = (pthread_descr) arg;
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#ifdef INIT_THREAD_SELF
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INIT_THREAD_SELF(self, self->p_nr);
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#endif
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/* Make sure our pid field is initialized, just in case we get there
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before our father has initialized it. */
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THREAD_SETMEM(self, p_pid, __getpid());
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/* Get the lock the manager will free once all is correctly set up. */
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__pthread_lock (THREAD_GETMEM(self, p_lock), NULL);
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/* Free it immediately. */
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__pthread_spin_unlock (THREAD_GETMEM(self, p_lock));
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/* Continue with the real function. */
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return pthread_start_thread (arg);
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}
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static int pthread_allocate_stack(const pthread_attr_t *attr,
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pthread_descr default_new_thread,
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int pagesize,
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pthread_descr * out_new_thread,
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char ** out_new_thread_bottom,
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char ** out_guardaddr,
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size_t * out_guardsize)
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{
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pthread_descr new_thread;
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char * new_thread_bottom;
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char * guardaddr;
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size_t stacksize, guardsize;
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if (attr != NULL && attr->__stackaddr_set)
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{
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/* The user provided a stack. */
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new_thread =
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(pthread_descr) ((long)(attr->__stackaddr) & -sizeof(void *)) - 1;
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new_thread_bottom = (char *) attr->__stackaddr - attr->__stacksize;
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guardaddr = NULL;
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guardsize = 0;
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__pthread_nonstandard_stacks = 1;
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}
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else
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{
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stacksize = STACK_SIZE - pagesize;
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if (attr != NULL)
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stacksize = MIN (stacksize, roundup(attr->__stacksize, pagesize));
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/* Allocate space for stack and thread descriptor at default address */
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new_thread = default_new_thread;
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new_thread_bottom = (char *) (new_thread + 1) - stacksize;
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if (mmap((caddr_t)((char *)(new_thread + 1) - INITIAL_STACK_SIZE),
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INITIAL_STACK_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
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MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED | MAP_GROWSDOWN,
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-1, 0) == MAP_FAILED)
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/* Bad luck, this segment is already mapped. */
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return -1;
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/* We manage to get a stack. Now see whether we need a guard
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and allocate it if necessary. Notice that the default
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attributes (stack_size = STACK_SIZE - pagesize) do not need
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a guard page, since the RLIMIT_STACK soft limit prevents stacks
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from running into one another. */
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if (stacksize == STACK_SIZE - pagesize)
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{
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/* We don't need a guard page. */
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guardaddr = NULL;
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guardsize = 0;
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}
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else
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{
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/* Put a bad page at the bottom of the stack */
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guardsize = attr->__guardsize;
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guardaddr = (void *)new_thread_bottom - guardsize;
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if (mmap ((caddr_t) guardaddr, guardsize, 0, MAP_FIXED, -1, 0)
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== MAP_FAILED)
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{
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/* We don't make this an error. */
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guardaddr = NULL;
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guardsize = 0;
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}
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}
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}
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/* Clear the thread data structure. */
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memset (new_thread, '\0', sizeof (*new_thread));
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*out_new_thread = new_thread;
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*out_new_thread_bottom = new_thread_bottom;
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*out_guardaddr = guardaddr;
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*out_guardsize = guardsize;
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return 0;
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}
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static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
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void * (*start_routine)(void *), void *arg,
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sigset_t * mask, int father_pid,
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int report_events,
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td_thr_events_t *event_maskp)
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{
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size_t sseg;
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int pid;
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pthread_descr new_thread;
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char * new_thread_bottom;
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pthread_t new_thread_id;
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char *guardaddr = NULL;
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size_t guardsize = 0;
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int pagesize = __getpagesize();
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/* First check whether we have to change the policy and if yes, whether
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we can do this. Normally this should be done by examining the
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return value of the __sched_setscheduler call in pthread_start_thread
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but this is hard to implement. FIXME */
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if (attr != NULL && attr->__schedpolicy != SCHED_OTHER && geteuid () != 0)
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return EPERM;
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/* Find a free segment for the thread, and allocate a stack if needed */
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for (sseg = 2; ; sseg++)
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{
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if (sseg >= PTHREAD_THREADS_MAX)
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return EAGAIN;
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if (__pthread_handles[sseg].h_descr != NULL)
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continue;
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if (pthread_allocate_stack(attr, thread_segment(sseg), pagesize,
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&new_thread, &new_thread_bottom,
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&guardaddr, &guardsize) == 0)
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break;
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}
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__pthread_handles_num++;
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/* Allocate new thread identifier */
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pthread_threads_counter += PTHREAD_THREADS_MAX;
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new_thread_id = sseg + pthread_threads_counter;
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/* Initialize the thread descriptor. Elements which have to be
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initialized to zero already have this value. */
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new_thread->p_tid = new_thread_id;
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new_thread->p_lock = &(__pthread_handles[sseg].h_lock);
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new_thread->p_cancelstate = PTHREAD_CANCEL_ENABLE;
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new_thread->p_canceltype = PTHREAD_CANCEL_DEFERRED;
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new_thread->p_errnop = &new_thread->p_errno;
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new_thread->p_h_errnop = &new_thread->p_h_errno;
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new_thread->p_resp = &new_thread->p_res;
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new_thread->p_guardaddr = guardaddr;
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new_thread->p_guardsize = guardsize;
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new_thread->p_self = new_thread;
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new_thread->p_nr = sseg;
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/* Initialize the thread handle */
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__pthread_init_lock(&__pthread_handles[sseg].h_lock);
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__pthread_handles[sseg].h_descr = new_thread;
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__pthread_handles[sseg].h_bottom = new_thread_bottom;
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/* Determine scheduling parameters for the thread */
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new_thread->p_start_args.schedpolicy = -1;
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if (attr != NULL) {
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new_thread->p_detached = attr->__detachstate;
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new_thread->p_userstack = attr->__stackaddr_set;
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switch(attr->__inheritsched) {
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case PTHREAD_EXPLICIT_SCHED:
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new_thread->p_start_args.schedpolicy = attr->__schedpolicy;
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memcpy (&new_thread->p_start_args.schedparam, &attr->__schedparam,
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sizeof (struct sched_param));
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break;
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case PTHREAD_INHERIT_SCHED:
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new_thread->p_start_args.schedpolicy = __sched_getscheduler(father_pid);
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__sched_getparam(father_pid, &new_thread->p_start_args.schedparam);
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break;
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}
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new_thread->p_priority =
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new_thread->p_start_args.schedparam.sched_priority;
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}
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/* Finish setting up arguments to pthread_start_thread */
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new_thread->p_start_args.start_routine = start_routine;
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new_thread->p_start_args.arg = arg;
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new_thread->p_start_args.mask = *mask;
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/* Make the new thread ID available already now. If any of the later
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functions fail we return an error value and the caller must not use
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the stored thread ID. */
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*thread = new_thread_id;
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/* Raise priority of thread manager if needed */
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__pthread_manager_adjust_prio(new_thread->p_priority);
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/* Do the cloning. We have to use two different functions depending
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on whether we are debugging or not. */
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pid = 0; /* Note that the thread never can have PID zero. */
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if (report_events)
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{
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/* See whether the TD_CREATE event bit is set in any of the
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masks. */
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int idx = __td_eventword (TD_CREATE);
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uint32_t mask = __td_eventmask (TD_CREATE);
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if ((mask & (__pthread_threads_events.event_bits[idx]
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| event_maskp->event_bits[idx])) != 0)
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{
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/* Lock the mutex the child will use now so that it will stop. */
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__pthread_lock(new_thread->p_lock, NULL);
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/* We have to report this event. */
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pid = __clone(pthread_start_thread_event, (void **) new_thread,
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CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
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__pthread_sig_cancel, new_thread);
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if (pid != -1)
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{
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/* Now fill in the information about the new thread in
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the newly created thread's data structure. We cannot let
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the new thread do this since we don't know whether it was
|
|
already scheduled when we send the event. */
|
|
new_thread->p_eventbuf.eventdata = new_thread;
|
|
new_thread->p_eventbuf.eventnum = TD_CREATE;
|
|
__pthread_last_event = new_thread;
|
|
|
|
/* We have to set the PID here since the callback function
|
|
in the debug library will need it and we cannot guarantee
|
|
the child got scheduled before the debugger. */
|
|
new_thread->p_pid = pid;
|
|
|
|
/* Now call the function which signals the event. */
|
|
__linuxthreads_create_event ();
|
|
|
|
/* Now restart the thread. */
|
|
__pthread_spin_unlock(new_thread->p_lock);
|
|
}
|
|
}
|
|
}
|
|
if (pid == 0)
|
|
pid = __clone(pthread_start_thread, (void **) new_thread,
|
|
CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
|
|
__pthread_sig_cancel, new_thread);
|
|
/* Check if cloning succeeded */
|
|
if (pid == -1) {
|
|
/* Free the stack if we allocated it */
|
|
if (attr == NULL || !attr->__stackaddr_set)
|
|
{
|
|
if (new_thread->p_guardsize != 0)
|
|
munmap(new_thread->p_guardaddr, new_thread->p_guardsize);
|
|
munmap((caddr_t)((char *)(new_thread+1) - INITIAL_STACK_SIZE),
|
|
INITIAL_STACK_SIZE);
|
|
}
|
|
__pthread_handles[sseg].h_descr = NULL;
|
|
__pthread_handles[sseg].h_bottom = NULL;
|
|
__pthread_handles_num--;
|
|
return errno;
|
|
}
|
|
/* Insert new thread in doubly linked list of active threads */
|
|
new_thread->p_prevlive = __pthread_main_thread;
|
|
new_thread->p_nextlive = __pthread_main_thread->p_nextlive;
|
|
__pthread_main_thread->p_nextlive->p_prevlive = new_thread;
|
|
__pthread_main_thread->p_nextlive = new_thread;
|
|
/* Set pid field of the new thread, in case we get there before the
|
|
child starts. */
|
|
new_thread->p_pid = pid;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Try to free the resources of a thread when requested by pthread_join
|
|
or pthread_detach on a terminated thread. */
|
|
|
|
static void pthread_free(pthread_descr th)
|
|
{
|
|
pthread_handle handle;
|
|
pthread_readlock_info *iter, *next;
|
|
|
|
ASSERT(th->p_exited);
|
|
/* Make the handle invalid */
|
|
handle = thread_handle(th->p_tid);
|
|
__pthread_lock(&handle->h_lock, NULL);
|
|
handle->h_descr = NULL;
|
|
handle->h_bottom = (char *)(-1L);
|
|
__pthread_spin_unlock(&handle->h_lock);
|
|
#ifdef FREE_THREAD
|
|
FREE_THREAD(th, th->p_nr);
|
|
#endif
|
|
/* One fewer threads in __pthread_handles */
|
|
__pthread_handles_num--;
|
|
|
|
/* Destroy read lock list, and list of free read lock structures.
|
|
If the former is not empty, it means the thread exited while
|
|
holding read locks! */
|
|
|
|
for (iter = th->p_readlock_list; iter != NULL; iter = next)
|
|
{
|
|
next = iter->pr_next;
|
|
free(iter);
|
|
}
|
|
|
|
for (iter = th->p_readlock_free; iter != NULL; iter = next)
|
|
{
|
|
next = iter->pr_next;
|
|
free(iter);
|
|
}
|
|
|
|
/* If initial thread, nothing to free */
|
|
if (th == &__pthread_initial_thread) return;
|
|
if (!th->p_userstack)
|
|
{
|
|
/* Free the stack and thread descriptor area */
|
|
if (th->p_guardsize != 0)
|
|
munmap(th->p_guardaddr, th->p_guardsize);
|
|
munmap((caddr_t) ((char *)(th+1) - STACK_SIZE), STACK_SIZE);
|
|
}
|
|
}
|
|
|
|
/* Handle threads that have exited */
|
|
|
|
static void pthread_exited(pid_t pid)
|
|
{
|
|
pthread_descr th;
|
|
int detached;
|
|
/* Find thread with that pid */
|
|
for (th = __pthread_main_thread->p_nextlive;
|
|
th != __pthread_main_thread;
|
|
th = th->p_nextlive) {
|
|
if (th->p_pid == pid) {
|
|
/* Remove thread from list of active threads */
|
|
th->p_nextlive->p_prevlive = th->p_prevlive;
|
|
th->p_prevlive->p_nextlive = th->p_nextlive;
|
|
/* Mark thread as exited, and if detached, free its resources */
|
|
__pthread_lock(th->p_lock, NULL);
|
|
th->p_exited = 1;
|
|
/* If we have to signal this event do it now. */
|
|
if (th->p_report_events)
|
|
{
|
|
/* See whether TD_DEATH is in any of the mask. */
|
|
int idx = __td_eventword (TD_REAP);
|
|
uint32_t mask = __td_eventmask (TD_REAP);
|
|
|
|
if ((mask & (__pthread_threads_events.event_bits[idx]
|
|
| th->p_eventbuf.eventmask.event_bits[idx])) != 0)
|
|
{
|
|
/* Yep, we have to signal the death. */
|
|
th->p_eventbuf.eventnum = TD_DEATH;
|
|
th->p_eventbuf.eventdata = th;
|
|
__pthread_last_event = th;
|
|
|
|
/* Now call the function to signal the event. */
|
|
__linuxthreads_reap_event();
|
|
}
|
|
}
|
|
detached = th->p_detached;
|
|
__pthread_spin_unlock(th->p_lock);
|
|
if (detached)
|
|
pthread_free(th);
|
|
break;
|
|
}
|
|
}
|
|
/* If all threads have exited and the main thread is pending on a
|
|
pthread_exit, wake up the main thread and terminate ourselves. */
|
|
if (main_thread_exiting &&
|
|
__pthread_main_thread->p_nextlive == __pthread_main_thread) {
|
|
restart(__pthread_main_thread);
|
|
_exit(0);
|
|
}
|
|
}
|
|
|
|
static void pthread_reap_children(void)
|
|
{
|
|
pid_t pid;
|
|
int status;
|
|
|
|
while ((pid = __libc_waitpid(-1, &status, WNOHANG | __WCLONE)) > 0) {
|
|
pthread_exited(pid);
|
|
if (WIFSIGNALED(status)) {
|
|
/* If a thread died due to a signal, send the same signal to
|
|
all other threads, including the main thread. */
|
|
pthread_kill_all_threads(WTERMSIG(status), 1);
|
|
_exit(0);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Try to free the resources of a thread when requested by pthread_join
|
|
or pthread_detach on a terminated thread. */
|
|
|
|
static void pthread_handle_free(pthread_t th_id)
|
|
{
|
|
pthread_handle handle = thread_handle(th_id);
|
|
pthread_descr th;
|
|
|
|
__pthread_lock(&handle->h_lock, NULL);
|
|
if (invalid_handle(handle, th_id)) {
|
|
/* pthread_reap_children has deallocated the thread already,
|
|
nothing needs to be done */
|
|
__pthread_spin_unlock(&handle->h_lock);
|
|
return;
|
|
}
|
|
th = handle->h_descr;
|
|
if (th->p_exited) {
|
|
__pthread_spin_unlock(&handle->h_lock);
|
|
pthread_free(th);
|
|
} else {
|
|
/* The Unix process of the thread is still running.
|
|
Mark the thread as detached so that the thread manager will
|
|
deallocate its resources when the Unix process exits. */
|
|
th->p_detached = 1;
|
|
__pthread_spin_unlock(&handle->h_lock);
|
|
}
|
|
}
|
|
|
|
/* Send a signal to all running threads */
|
|
|
|
static void pthread_kill_all_threads(int sig, int main_thread_also)
|
|
{
|
|
pthread_descr th;
|
|
for (th = __pthread_main_thread->p_nextlive;
|
|
th != __pthread_main_thread;
|
|
th = th->p_nextlive) {
|
|
kill(th->p_pid, sig);
|
|
}
|
|
if (main_thread_also) {
|
|
kill(__pthread_main_thread->p_pid, sig);
|
|
}
|
|
}
|
|
|
|
/* Process-wide exit() */
|
|
|
|
static void pthread_handle_exit(pthread_descr issuing_thread, int exitcode)
|
|
{
|
|
pthread_descr th;
|
|
__pthread_exit_requested = 1;
|
|
__pthread_exit_code = exitcode;
|
|
/* Send the CANCEL signal to all running threads, including the main
|
|
thread, but excluding the thread from which the exit request originated
|
|
(that thread must complete the exit, e.g. calling atexit functions
|
|
and flushing stdio buffers). */
|
|
for (th = issuing_thread->p_nextlive;
|
|
th != issuing_thread;
|
|
th = th->p_nextlive) {
|
|
kill(th->p_pid, __pthread_sig_cancel);
|
|
}
|
|
/* Now, wait for all these threads, so that they don't become zombies
|
|
and their times are properly added to the thread manager's times. */
|
|
for (th = issuing_thread->p_nextlive;
|
|
th != issuing_thread;
|
|
th = th->p_nextlive) {
|
|
waitpid(th->p_pid, NULL, __WCLONE);
|
|
}
|
|
restart(issuing_thread);
|
|
_exit(0);
|
|
}
|
|
|
|
/* Handler for __pthread_sig_cancel in thread manager thread */
|
|
|
|
void __pthread_manager_sighandler(int sig)
|
|
{
|
|
terminated_children = 1;
|
|
}
|
|
|
|
/* Adjust priority of thread manager so that it always run at a priority
|
|
higher than all threads */
|
|
|
|
void __pthread_manager_adjust_prio(int thread_prio)
|
|
{
|
|
struct sched_param param;
|
|
|
|
if (thread_prio <= __pthread_manager_thread.p_priority) return;
|
|
param.sched_priority =
|
|
thread_prio < __sched_get_priority_max(SCHED_FIFO)
|
|
? thread_prio + 1 : thread_prio;
|
|
__sched_setscheduler(__pthread_manager_thread.p_pid, SCHED_FIFO, ¶m);
|
|
__pthread_manager_thread.p_priority = thread_prio;
|
|
}
|