diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/timer_routines.c')
| -rw-r--r-- | sysdeps/unix/sysv/linux/timer_routines.c | 155 |
1 files changed, 1 insertions, 154 deletions
diff --git a/sysdeps/unix/sysv/linux/timer_routines.c b/sysdeps/unix/sysv/linux/timer_routines.c index 2ad1e7baf2..6e25b021ab 100644 --- a/sysdeps/unix/sysv/linux/timer_routines.c +++ b/sysdeps/unix/sysv/linux/timer_routines.c @@ -1,154 +1 @@ -/* Copyright (C) 2003-2023 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public License as - published by the Free Software Foundation; either version 2.1 of the - License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; see the file COPYING.LIB. If - not, see <https://www.gnu.org/licenses/>. */ - -#include <errno.h> -#include <setjmp.h> -#include <signal.h> -#include <stdbool.h> -#include <sysdep-cancel.h> -#include <pthreadP.h> -#include "kernel-posix-timers.h" - - -/* List of active SIGEV_THREAD timers. */ -struct timer *__timer_active_sigev_thread; - -/* Lock for _timer_active_sigev_thread. */ -pthread_mutex_t __timer_active_sigev_thread_lock = PTHREAD_MUTEX_INITIALIZER; - -struct thread_start_data -{ - void (*thrfunc) (sigval_t); - sigval_t sival; -}; - - -/* Helper thread to call the user-provided function. */ -static void * -timer_sigev_thread (void *arg) -{ - signal_unblock_sigtimer (); - - struct thread_start_data *td = (struct thread_start_data *) arg; - void (*thrfunc) (sigval_t) = td->thrfunc; - sigval_t sival = td->sival; - - /* The TD object was allocated in timer_helper_thread. */ - free (td); - - /* Call the user-provided function. */ - thrfunc (sival); - - return NULL; -} - - -/* Helper function to support starting threads for SIGEV_THREAD. */ -static _Noreturn void * -timer_helper_thread (void *arg) -{ - /* Endless loop of waiting for signals. The loop is only ended when - the thread is canceled. */ - while (1) - { - siginfo_t si; - - while (__sigwaitinfo (&sigtimer_set, &si) < 0); - if (si.si_code == SI_TIMER) - { - struct timer *tk = (struct timer *) si.si_ptr; - - /* Check the timer is still used and will not go away - while we are reading the values here. */ - __pthread_mutex_lock (&__timer_active_sigev_thread_lock); - - struct timer *runp = __timer_active_sigev_thread; - while (runp != NULL) - if (runp == tk) - break; - else - runp = runp->next; - - if (runp != NULL) - { - struct thread_start_data *td = malloc (sizeof (*td)); - - /* There is not much we can do if the allocation fails. */ - if (td != NULL) - { - /* This is the signal we are waiting for. */ - td->thrfunc = tk->thrfunc; - td->sival = tk->sival; - - pthread_t th; - __pthread_create (&th, &tk->attr, timer_sigev_thread, td); - } - } - - __pthread_mutex_unlock (&__timer_active_sigev_thread_lock); - } - } -} - - -/* Control variable for helper thread creation. */ -pthread_once_t __timer_helper_once = PTHREAD_ONCE_INIT; - - -/* TID of the helper thread. */ -pid_t __timer_helper_tid; - - -/* Reset variables so that after a fork a new helper thread gets started. */ -void -__timer_fork_subprocess (void) -{ - __timer_helper_once = PTHREAD_ONCE_INIT; - __timer_helper_tid = 0; -} - - -void -__timer_start_helper_thread (void) -{ - /* The helper thread needs only very little resources - and should go away automatically when canceled. */ - pthread_attr_t attr; - __pthread_attr_init (&attr); - __pthread_attr_setstacksize (&attr, __pthread_get_minstack (&attr)); - - /* Block all signals in the helper thread but SIGSETXID. */ - sigset_t ss; - __sigfillset (&ss); - __sigdelset (&ss, SIGSETXID); - int res = __pthread_attr_setsigmask_internal (&attr, &ss); - if (res != 0) - { - __pthread_attr_destroy (&attr); - return; - } - - /* Create the helper thread for this timer. */ - pthread_t th; - res = __pthread_create (&th, &attr, timer_helper_thread, NULL); - if (res == 0) - /* We managed to start the helper thread. */ - __timer_helper_tid = ((struct pthread *) th)->tid; - - /* No need for the attribute anymore. */ - __pthread_attr_destroy (&attr); -} +/* Empty. */ |