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-rw-r--r--linuxthreads/sysdeps/pthread/timer_routines.c573
1 files changed, 0 insertions, 573 deletions
diff --git a/linuxthreads/sysdeps/pthread/timer_routines.c b/linuxthreads/sysdeps/pthread/timer_routines.c
deleted file mode 100644
index 3877b86fbb..0000000000
--- a/linuxthreads/sysdeps/pthread/timer_routines.c
+++ /dev/null
@@ -1,573 +0,0 @@
-/* Helper code for POSIX timer implementation on LinuxThreads.
- Copyright (C) 2000, 2001, 2002, 2004 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Kaz Kylheku <kaz@ashi.footprints.net>.
-
- 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,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
-
-#include <assert.h>
-#include <errno.h>
-#include <pthread.h>
-#include <stddef.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sysdep.h>
-#include <time.h>
-#include <unistd.h>
-#include <sys/syscall.h>
-
-#include "posix-timer.h"
-
-
-/* Number of threads used. */
-#define THREAD_MAXNODES 16
-
-/* Array containing the descriptors for the used threads. */
-static struct thread_node thread_array[THREAD_MAXNODES];
-
-/* Static array with the structures for all the timers. */
-struct timer_node __timer_array[TIMER_MAX];
-
-/* Global lock to protect operation on the lists. */
-pthread_mutex_t __timer_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-/* Variable to protext initialization. */
-pthread_once_t __timer_init_once_control = PTHREAD_ONCE_INIT;
-
-/* Nonzero if initialization of timer implementation failed. */
-int __timer_init_failed;
-
-/* Node for the thread used to deliver signals. */
-struct thread_node __timer_signal_thread_rclk;
-
-/* Lists to keep free and used timers and threads. */
-struct list_links timer_free_list;
-struct list_links thread_free_list;
-struct list_links thread_active_list;
-
-
-#ifdef __NR_rt_sigqueueinfo
-extern int __syscall_rt_sigqueueinfo (int, int, siginfo_t *);
-#endif
-
-
-/* List handling functions. */
-static inline void
-list_init (struct list_links *list)
-{
- list->next = list->prev = list;
-}
-
-static inline void
-list_append (struct list_links *list, struct list_links *newp)
-{
- newp->prev = list->prev;
- newp->next = list;
- list->prev->next = newp;
- list->prev = newp;
-}
-
-static inline void
-list_insbefore (struct list_links *list, struct list_links *newp)
-{
- list_append (list, newp);
-}
-
-/*
- * Like list_unlink_ip, except that calling it on a node that
- * is already unlinked is disastrous rather than a noop.
- */
-
-static inline void
-list_unlink (struct list_links *list)
-{
- struct list_links *lnext = list->next, *lprev = list->prev;
-
- lnext->prev = lprev;
- lprev->next = lnext;
-}
-
-static inline struct list_links *
-list_first (struct list_links *list)
-{
- return list->next;
-}
-
-static inline struct list_links *
-list_null (struct list_links *list)
-{
- return list;
-}
-
-static inline struct list_links *
-list_next (struct list_links *list)
-{
- return list->next;
-}
-
-static inline int
-list_isempty (struct list_links *list)
-{
- return list->next == list;
-}
-
-
-/* Functions build on top of the list functions. */
-static inline struct thread_node *
-thread_links2ptr (struct list_links *list)
-{
- return (struct thread_node *) ((char *) list
- - offsetof (struct thread_node, links));
-}
-
-static inline struct timer_node *
-timer_links2ptr (struct list_links *list)
-{
- return (struct timer_node *) ((char *) list
- - offsetof (struct timer_node, links));
-}
-
-
-/* Initialize a newly allocated thread structure. */
-static void
-thread_init (struct thread_node *thread, const pthread_attr_t *attr, clockid_t clock_id)
-{
- if (attr != NULL)
- thread->attr = *attr;
- else
- {
- pthread_attr_init (&thread->attr);
- pthread_attr_setdetachstate (&thread->attr, PTHREAD_CREATE_DETACHED);
- }
-
- thread->exists = 0;
- list_init (&thread->timer_queue);
- pthread_cond_init (&thread->cond, 0);
- thread->current_timer = 0;
- thread->captured = pthread_self ();
- thread->clock_id = clock_id;
-}
-
-
-/* Initialize the global lists, and acquire global resources. Error
- reporting is done by storing a non-zero value to the global variable
- timer_init_failed. */
-static void
-init_module (void)
-{
- int i;
-
- list_init (&timer_free_list);
- list_init (&thread_free_list);
- list_init (&thread_active_list);
-
- for (i = 0; i < TIMER_MAX; ++i)
- {
- list_append (&timer_free_list, &__timer_array[i].links);
- __timer_array[i].inuse = TIMER_FREE;
- }
-
- for (i = 0; i < THREAD_MAXNODES; ++i)
- list_append (&thread_free_list, &thread_array[i].links);
-
- thread_init (&__timer_signal_thread_rclk, 0, CLOCK_REALTIME);
-}
-
-
-/* This is a handler executed in a child process after a fork()
- occurs. It reinitializes the module, resetting all of the data
- structures to their initial state. The mutex is initialized in
- case it was locked in the parent process. */
-static void
-reinit_after_fork (void)
-{
- init_module ();
- pthread_mutex_init (&__timer_mutex, 0);
-}
-
-
-/* Called once form pthread_once in timer_init. This initializes the
- module and ensures that reinit_after_fork will be executed in any
- child process. */
-void
-__timer_init_once (void)
-{
- init_module ();
- pthread_atfork (0, 0, reinit_after_fork);
-}
-
-
-/* Deinitialize a thread that is about to be deallocated. */
-static void
-thread_deinit (struct thread_node *thread)
-{
- assert (list_isempty (&thread->timer_queue));
- pthread_cond_destroy (&thread->cond);
-}
-
-
-/* Allocate a thread structure from the global free list. Global
- mutex lock must be held by caller. The thread is moved to
- the active list. */
-struct thread_node *
-__timer_thread_alloc (const pthread_attr_t *desired_attr, clockid_t clock_id)
-{
- struct list_links *node = list_first (&thread_free_list);
-
- if (node != list_null (&thread_free_list))
- {
- struct thread_node *thread = thread_links2ptr (node);
- list_unlink (node);
- thread_init (thread, desired_attr, clock_id);
- list_append (&thread_active_list, node);
- return thread;
- }
-
- return 0;
-}
-
-
-/* Return a thread structure to the global free list. Global lock
- must be held by caller. */
-void
-__timer_thread_dealloc (struct thread_node *thread)
-{
- thread_deinit (thread);
- list_unlink (&thread->links);
- list_append (&thread_free_list, &thread->links);
-}
-
-
-/* Each of our threads which terminates executes this cleanup
- handler. We never terminate threads ourselves; if a thread gets here
- it means that the evil application has killed it. If the thread has
- timers, these require servicing and so we must hire a replacement
- thread right away. We must also unblock another thread that may
- have been waiting for this thread to finish servicing a timer (see
- timer_delete()). */
-
-static void
-thread_cleanup (void *val)
-{
- if (val != NULL)
- {
- struct thread_node *thread = val;
-
- /* How did the signal thread get killed? */
- assert (thread != &__timer_signal_thread_rclk);
-
- pthread_mutex_lock (&__timer_mutex);
-
- thread->exists = 0;
-
- /* We are no longer processing a timer event. */
- thread->current_timer = 0;
-
- if (list_isempty (&thread->timer_queue))
- __timer_thread_dealloc (thread);
- else
- (void) __timer_thread_start (thread);
-
- pthread_mutex_unlock (&__timer_mutex);
-
- /* Unblock potentially blocked timer_delete(). */
- pthread_cond_broadcast (&thread->cond);
- }
-}
-
-
-/* Handle a timer which is supposed to go off now. */
-static void
-thread_expire_timer (struct thread_node *self, struct timer_node *timer)
-{
- self->current_timer = timer; /* Lets timer_delete know timer is running. */
-
- pthread_mutex_unlock (&__timer_mutex);
-
- switch (__builtin_expect (timer->event.sigev_notify, SIGEV_SIGNAL))
- {
- case SIGEV_NONE:
- break;
-
- case SIGEV_SIGNAL:
-#ifdef __NR_rt_sigqueueinfo
- {
- siginfo_t info;
-
- /* First, clear the siginfo_t structure, so that we don't pass our
- stack content to other tasks. */
- memset (&info, 0, sizeof (siginfo_t));
- /* We must pass the information about the data in a siginfo_t
- value. */
- info.si_signo = timer->event.sigev_signo;
- info.si_code = SI_TIMER;
- info.si_pid = timer->creator_pid;
- info.si_uid = getuid ();
- info.si_value = timer->event.sigev_value;
-
- INLINE_SYSCALL (rt_sigqueueinfo, 3, info.si_pid, info.si_signo, &info);
- }
-#else
- if (pthread_kill (self->captured, timer->event.sigev_signo) != 0)
- {
- if (pthread_kill (self->id, timer->event.sigev_signo) != 0)
- abort ();
- }
-#endif
- break;
-
- case SIGEV_THREAD:
- timer->event.sigev_notify_function (timer->event.sigev_value);
- break;
-
- default:
- assert (! "unknown event");
- break;
- }
-
- pthread_mutex_lock (&__timer_mutex);
-
- self->current_timer = 0;
-
- pthread_cond_broadcast (&self->cond);
-}
-
-
-/* Thread function; executed by each timer thread. The job of this
- function is to wait on the thread's timer queue and expire the
- timers in chronological order as close to their scheduled time as
- possible. */
-static void
-__attribute__ ((noreturn))
-thread_func (void *arg)
-{
- struct thread_node *self = arg;
-
- /* Register cleanup handler, in case rogue application terminates
- this thread. (This cannot happen to __timer_signal_thread, which
- doesn't invoke application callbacks). */
-
- pthread_cleanup_push (thread_cleanup, self);
-
- pthread_mutex_lock (&__timer_mutex);
-
- while (1)
- {
- struct list_links *first;
- struct timer_node *timer = NULL;
-
- /* While the timer queue is not empty, inspect the first node. */
- first = list_first (&self->timer_queue);
- if (first != list_null (&self->timer_queue))
- {
- struct timespec now;
-
- timer = timer_links2ptr (first);
-
- /* This assumes that the elements of the list of one thread
- are all for the same clock. */
- clock_gettime (timer->clock, &now);
-
- while (1)
- {
- /* If the timer is due or overdue, remove it from the queue.
- If it's a periodic timer, re-compute its new time and
- requeue it. Either way, perform the timer expiry. */
- if (timespec_compare (&now, &timer->expirytime) < 0)
- break;
-
- list_unlink_ip (first);
-
- if (__builtin_expect (timer->value.it_interval.tv_sec, 0) != 0
- || timer->value.it_interval.tv_nsec != 0)
- {
- timer->overrun_count = 0;
- timespec_add (&timer->expirytime, &timer->expirytime,
- &timer->value.it_interval);
- while (timespec_compare (&timer->expirytime, &now) < 0)
- {
- timespec_add (&timer->expirytime, &timer->expirytime,
- &timer->value.it_interval);
- if (timer->overrun_count < DELAYTIMER_MAX)
- ++timer->overrun_count;
- }
- __timer_thread_queue_timer (self, timer);
- }
-
- thread_expire_timer (self, timer);
-
- first = list_first (&self->timer_queue);
- if (first == list_null (&self->timer_queue))
- break;
-
- timer = timer_links2ptr (first);
- }
- }
-
- /* If the queue is not empty, wait until the expiry time of the
- first node. Otherwise wait indefinitely. Insertions at the
- head of the queue must wake up the thread by broadcasting
- this condition variable. */
- if (timer != NULL)
- pthread_cond_timedwait (&self->cond, &__timer_mutex,
- &timer->expirytime);
- else
- pthread_cond_wait (&self->cond, &__timer_mutex);
- }
- /* This macro will never be executed since the while loop loops
- forever - but we have to add it for proper nesting. */
- pthread_cleanup_pop (1);
-}
-
-
-/* Enqueue a timer in wakeup order in the thread's timer queue.
- Returns 1 if the timer was inserted at the head of the queue,
- causing the queue's next wakeup time to change. */
-
-int
-__timer_thread_queue_timer (struct thread_node *thread,
- struct timer_node *insert)
-{
- struct list_links *iter;
- int athead = 1;
-
- for (iter = list_first (&thread->timer_queue);
- iter != list_null (&thread->timer_queue);
- iter = list_next (iter))
- {
- struct timer_node *timer = timer_links2ptr (iter);
-
- if (timespec_compare (&insert->expirytime, &timer->expirytime) < 0)
- break;
- athead = 0;
- }
-
- list_insbefore (iter, &insert->links);
- return athead;
-}
-
-
-/* Start a thread and associate it with the given thread node. Global
- lock must be held by caller. */
-int
-__timer_thread_start (struct thread_node *thread)
-{
- int retval = 1;
-
- assert (!thread->exists);
- thread->exists = 1;
-
- if (pthread_create (&thread->id, &thread->attr,
- (void *(*) (void *)) thread_func, thread) != 0)
- {
- thread->exists = 0;
- retval = -1;
- }
-
- return retval;
-}
-
-
-void
-__timer_thread_wakeup (struct thread_node *thread)
-{
- pthread_cond_broadcast (&thread->cond);
-}
-
-
-/* Compare two pthread_attr_t thread attributes for exact equality.
- Returns 1 if they are equal, otherwise zero if they are not equal or
- contain illegal values. This version is LinuxThreads-specific for
- performance reason. One could use the access functions to get the
- values of all the fields of the attribute structure. */
-static int
-thread_attr_compare (const pthread_attr_t *left, const pthread_attr_t *right)
-{
- return (left->__detachstate == right->__detachstate
- && left->__schedpolicy == right->__schedpolicy
- && left->__guardsize == right->__guardsize
- && (left->__schedparam.sched_priority
- == right->__schedparam.sched_priority)
- && left->__inheritsched == right->__inheritsched
- && left->__scope == right->__scope
- && left->__stacksize == right->__stacksize
- && left->__stackaddr_set == right->__stackaddr_set
- && (left->__stackaddr_set
- || left->__stackaddr == right->__stackaddr));
-}
-
-
-/* Search the list of active threads and find one which has matching
- attributes. Global mutex lock must be held by caller. */
-struct thread_node *
-__timer_thread_find_matching (const pthread_attr_t *desired_attr,
- clockid_t desired_clock_id)
-{
- struct list_links *iter = list_first (&thread_active_list);
-
- while (iter != list_null (&thread_active_list))
- {
- struct thread_node *candidate = thread_links2ptr (iter);
-
- if (thread_attr_compare (desired_attr, &candidate->attr)
- && desired_clock_id == candidate->clock_id)
- return candidate;
-
- iter = list_next (iter);
- }
-
- return NULL;
-}
-
-
-/* Grab a free timer structure from the global free list. The global
- lock must be held by the caller. */
-struct timer_node *
-__timer_alloc (void)
-{
- struct list_links *node = list_first (&timer_free_list);
-
- if (node != list_null (&timer_free_list))
- {
- struct timer_node *timer = timer_links2ptr (node);
- list_unlink_ip (node);
- timer->inuse = TIMER_INUSE;
- timer->refcount = 1;
- return timer;
- }
-
- return NULL;
-}
-
-
-/* Return a timer structure to the global free list. The global lock
- must be held by the caller. */
-void
-__timer_dealloc (struct timer_node *timer)
-{
- assert (timer->refcount == 0);
- timer->thread = NULL; /* Break association between timer and thread. */
- timer->inuse = TIMER_FREE;
- list_append (&timer_free_list, &timer->links);
-}
-
-
-/* Thread cancellation handler which unlocks a mutex. */
-void
-__timer_mutex_cancel_handler (void *arg)
-{
- pthread_mutex_unlock (arg);
-}