From 6b6ede3d15f04fe825cfa9f697507457e3640344 Mon Sep 17 00:00:00 2001 From: Waldemar Brodkorb Date: Sat, 14 Feb 2015 23:00:19 -0600 Subject: resolve merge --- libpthread/linuxthreads/rwlock.c | 250 ++++++--------------------------------- 1 file changed, 39 insertions(+), 211 deletions(-) (limited to 'libpthread/linuxthreads/rwlock.c') diff --git a/libpthread/linuxthreads/rwlock.c b/libpthread/linuxthreads/rwlock.c index af72876f5..3ab940261 100644 --- a/libpthread/linuxthreads/rwlock.c +++ b/libpthread/linuxthreads/rwlock.c @@ -1,24 +1,23 @@ /* Read-write lock implementation. - Copyright (C) 1998, 2000 Free Software Foundation, Inc. + Copyright (C) 1998 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Xavier Leroy and Ulrich Drepper , 1998. 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 + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 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. + Library 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 . */ + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + see . */ -#include #include #include #include @@ -27,33 +26,6 @@ #include "spinlock.h" #include "restart.h" -/* Function called by pthread_cancel to remove the thread from - waiting inside pthread_rwlock_timedrdlock or pthread_rwlock_timedwrlock. */ - -static int rwlock_rd_extricate_func(void *obj, pthread_descr th) -{ - pthread_rwlock_t *rwlock = obj; - int did_remove = 0; - - __pthread_lock(&rwlock->__rw_lock, NULL); - did_remove = remove_from_queue(&rwlock->__rw_read_waiting, th); - __pthread_unlock(&rwlock->__rw_lock); - - return did_remove; -} - -static int rwlock_wr_extricate_func(void *obj, pthread_descr th) -{ - pthread_rwlock_t *rwlock = obj; - int did_remove = 0; - - __pthread_lock(&rwlock->__rw_lock, NULL); - did_remove = remove_from_queue(&rwlock->__rw_write_waiting, th); - __pthread_unlock(&rwlock->__rw_lock); - - return did_remove; -} - /* * Check whether the calling thread already owns one or more read locks on the * specified lock. If so, return a pointer to the read lock info structure @@ -65,8 +37,7 @@ rwlock_is_in_list(pthread_descr self, pthread_rwlock_t *rwlock) { pthread_readlock_info *info; - for (info = THREAD_GETMEM (self, p_readlock_list); info != NULL; - info = info->pr_next) + for (info = self->p_readlock_list; info != NULL; info = info->pr_next) { if (info->pr_lock == rwlock) return info; @@ -86,10 +57,10 @@ rwlock_is_in_list(pthread_descr self, pthread_rwlock_t *rwlock) static pthread_readlock_info * rwlock_add_to_list(pthread_descr self, pthread_rwlock_t *rwlock) { - pthread_readlock_info *info = THREAD_GETMEM (self, p_readlock_free); + pthread_readlock_info *info = self->p_readlock_free; if (info != NULL) - THREAD_SETMEM (self, p_readlock_free, info->pr_next); + self->p_readlock_free = info->pr_next; else info = malloc(sizeof *info); @@ -98,8 +69,8 @@ rwlock_add_to_list(pthread_descr self, pthread_rwlock_t *rwlock) info->pr_lock_count = 1; info->pr_lock = rwlock; - info->pr_next = THREAD_GETMEM (self, p_readlock_list); - THREAD_SETMEM (self, p_readlock_list, info); + info->pr_next = self->p_readlock_list; + self->p_readlock_list = info; return info; } @@ -189,12 +160,11 @@ rwlock_have_already(pthread_descr *pself, pthread_rwlock_t *rwlock, if (rwlock->__rw_kind == PTHREAD_RWLOCK_PREFER_WRITER_NP) { if (!self) - *pself = self = thread_self(); + self = thread_self(); existing = rwlock_is_in_list(self, rwlock); - if (existing != NULL - || THREAD_GETMEM (self, p_untracked_readlock_count) > 0) + if (existing != NULL || self->p_untracked_readlock_count > 0) have_lock_already = 1; else { @@ -206,13 +176,14 @@ rwlock_have_already(pthread_descr *pself, pthread_rwlock_t *rwlock, *pout_of_mem = out_of_mem; *pexisting = existing; + *pself = self; return have_lock_already; } int -__pthread_rwlock_init (pthread_rwlock_t *rwlock, - const pthread_rwlockattr_t *attr) +pthread_rwlock_init (pthread_rwlock_t *rwlock, + const pthread_rwlockattr_t *attr) { __pthread_init_lock(&rwlock->__rw_lock); rwlock->__rw_readers = 0; @@ -233,11 +204,10 @@ __pthread_rwlock_init (pthread_rwlock_t *rwlock, return 0; } -strong_alias (__pthread_rwlock_init, pthread_rwlock_init) int -__pthread_rwlock_destroy (pthread_rwlock_t *rwlock) +pthread_rwlock_destroy (pthread_rwlock_t *rwlock) { int readers; _pthread_descr writer; @@ -252,75 +222,22 @@ __pthread_rwlock_destroy (pthread_rwlock_t *rwlock) return 0; } -strong_alias (__pthread_rwlock_destroy, pthread_rwlock_destroy) int -__pthread_rwlock_rdlock (pthread_rwlock_t *rwlock) +pthread_rwlock_rdlock (pthread_rwlock_t *rwlock) { pthread_descr self = NULL; pthread_readlock_info *existing; int out_of_mem, have_lock_already; have_lock_already = rwlock_have_already(&self, rwlock, - &existing, &out_of_mem); - - if (self == NULL) - self = thread_self (); + &existing, &out_of_mem); for (;;) { - __pthread_lock (&rwlock->__rw_lock, self); - - if (rwlock_can_rdlock(rwlock, have_lock_already)) - break; - - enqueue (&rwlock->__rw_read_waiting, self); - __pthread_unlock (&rwlock->__rw_lock); - suspend (self); /* This is not a cancellation point */ - } - - ++rwlock->__rw_readers; - __pthread_unlock (&rwlock->__rw_lock); - - if (have_lock_already || out_of_mem) - { - if (existing != NULL) - ++existing->pr_lock_count; - else - ++self->p_untracked_readlock_count; - } - - return 0; -} -strong_alias (__pthread_rwlock_rdlock, pthread_rwlock_rdlock) - -int -__pthread_rwlock_timedrdlock (pthread_rwlock_t *rwlock, - const struct timespec *abstime) -{ - pthread_descr self = NULL; - pthread_readlock_info *existing; - int out_of_mem, have_lock_already; - pthread_extricate_if extr; - - if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) - return EINVAL; - - have_lock_already = rwlock_have_already(&self, rwlock, - &existing, &out_of_mem); - - if (self == NULL) - self = thread_self (); - - /* Set up extrication interface */ - extr.pu_object = rwlock; - extr.pu_extricate_func = rwlock_rd_extricate_func; - - /* Register extrication interface */ - __pthread_set_own_extricate_if (self, &extr); + if (self == NULL) + self = thread_self (); - for (;;) - { __pthread_lock (&rwlock->__rw_lock, self); if (rwlock_can_rdlock(rwlock, have_lock_already)) @@ -328,45 +245,25 @@ __pthread_rwlock_timedrdlock (pthread_rwlock_t *rwlock, enqueue (&rwlock->__rw_read_waiting, self); __pthread_unlock (&rwlock->__rw_lock); - /* This is not a cancellation point */ - if (timedsuspend (self, abstime) == 0) - { - int was_on_queue; - - __pthread_lock (&rwlock->__rw_lock, self); - was_on_queue = remove_from_queue (&rwlock->__rw_read_waiting, self); - __pthread_unlock (&rwlock->__rw_lock); - - if (was_on_queue) - { - __pthread_set_own_extricate_if (self, 0); - return ETIMEDOUT; - } - - /* Eat the outstanding restart() from the signaller */ - suspend (self); - } + suspend (self); /* This is not a cancellation point */ } - __pthread_set_own_extricate_if (self, 0); - ++rwlock->__rw_readers; __pthread_unlock (&rwlock->__rw_lock); if (have_lock_already || out_of_mem) { if (existing != NULL) - ++existing->pr_lock_count; + existing->pr_lock_count++; else - ++self->p_untracked_readlock_count; + self->p_untracked_readlock_count++; } return 0; } -strong_alias (__pthread_rwlock_timedrdlock, pthread_rwlock_timedrdlock) int -__pthread_rwlock_tryrdlock (pthread_rwlock_t *rwlock) +pthread_rwlock_tryrdlock (pthread_rwlock_t *rwlock) { pthread_descr self = thread_self(); pthread_readlock_info *existing; @@ -397,19 +294,18 @@ __pthread_rwlock_tryrdlock (pthread_rwlock_t *rwlock) if (have_lock_already || out_of_mem) { if (existing != NULL) - ++existing->pr_lock_count; + existing->pr_lock_count++; else - ++self->p_untracked_readlock_count; + self->p_untracked_readlock_count++; } } return retval; } -strong_alias (__pthread_rwlock_tryrdlock, pthread_rwlock_tryrdlock) int -__pthread_rwlock_wrlock (pthread_rwlock_t *rwlock) +pthread_rwlock_wrlock (pthread_rwlock_t *rwlock) { pthread_descr self = thread_self (); @@ -429,68 +325,10 @@ __pthread_rwlock_wrlock (pthread_rwlock_t *rwlock) suspend (self); /* This is not a cancellation point */ } } -strong_alias (__pthread_rwlock_wrlock, pthread_rwlock_wrlock) int -__pthread_rwlock_timedwrlock (pthread_rwlock_t *rwlock, - const struct timespec *abstime) -{ - pthread_descr self; - pthread_extricate_if extr; - - if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) - return EINVAL; - - self = thread_self (); - - /* Set up extrication interface */ - extr.pu_object = rwlock; - extr.pu_extricate_func = rwlock_wr_extricate_func; - - /* Register extrication interface */ - __pthread_set_own_extricate_if (self, &extr); - - while(1) - { - __pthread_lock (&rwlock->__rw_lock, self); - - if (rwlock->__rw_readers == 0 && rwlock->__rw_writer == NULL) - { - rwlock->__rw_writer = self; - __pthread_set_own_extricate_if (self, 0); - __pthread_unlock (&rwlock->__rw_lock); - return 0; - } - - /* Suspend ourselves, then try again */ - enqueue (&rwlock->__rw_write_waiting, self); - __pthread_unlock (&rwlock->__rw_lock); - /* This is not a cancellation point */ - if (timedsuspend (self, abstime) == 0) - { - int was_on_queue; - - __pthread_lock (&rwlock->__rw_lock, self); - was_on_queue = remove_from_queue (&rwlock->__rw_write_waiting, self); - __pthread_unlock (&rwlock->__rw_lock); - - if (was_on_queue) - { - __pthread_set_own_extricate_if (self, 0); - return ETIMEDOUT; - } - - /* Eat the outstanding restart() from the signaller */ - suspend (self); - } - } -} -strong_alias (__pthread_rwlock_timedwrlock, pthread_rwlock_timedwrlock) - - -int -__pthread_rwlock_trywrlock (pthread_rwlock_t *rwlock) +pthread_rwlock_trywrlock (pthread_rwlock_t *rwlock) { int result = EBUSY; @@ -504,11 +342,10 @@ __pthread_rwlock_trywrlock (pthread_rwlock_t *rwlock) return result; } -strong_alias (__pthread_rwlock_trywrlock, pthread_rwlock_trywrlock) int -__pthread_rwlock_unlock (pthread_rwlock_t *rwlock) +pthread_rwlock_unlock (pthread_rwlock_t *rwlock) { pthread_descr torestart; pthread_descr th; @@ -524,9 +361,8 @@ __pthread_rwlock_unlock (pthread_rwlock_t *rwlock) } rwlock->__rw_writer = NULL; - if ((rwlock->__rw_kind == PTHREAD_RWLOCK_PREFER_READER_NP - && !queue_is_empty(&rwlock->__rw_read_waiting)) - || (th = dequeue(&rwlock->__rw_write_waiting)) == NULL) + if (rwlock->__rw_kind == PTHREAD_RWLOCK_PREFER_READER_NP + || (th = dequeue (&rwlock->__rw_write_waiting)) == NULL) { /* Restart all waiting readers. */ torestart = rwlock->__rw_read_waiting; @@ -573,22 +409,20 @@ __pthread_rwlock_unlock (pthread_rwlock_t *rwlock) { if (victim->pr_lock_count == 0) { - victim->pr_next = THREAD_GETMEM (self, p_readlock_free); - THREAD_SETMEM (self, p_readlock_free, victim); + victim->pr_next = self->p_readlock_free; + self->p_readlock_free = victim; } } else { - int val = THREAD_GETMEM (self, p_untracked_readlock_count); - if (val > 0) - THREAD_SETMEM (self, p_untracked_readlock_count, val - 1); + if (self->p_untracked_readlock_count > 0) + self->p_untracked_readlock_count--; } } } return 0; } -strong_alias (__pthread_rwlock_unlock, pthread_rwlock_unlock) @@ -596,18 +430,17 @@ int pthread_rwlockattr_init (pthread_rwlockattr_t *attr) { attr->__lockkind = 0; - attr->__pshared = PTHREAD_PROCESS_PRIVATE; + attr->__pshared = 0; return 0; } int -__pthread_rwlockattr_destroy (pthread_rwlockattr_t *attr) +pthread_rwlockattr_destroy (pthread_rwlockattr_t *attr attribute_unused) { return 0; } -strong_alias (__pthread_rwlockattr_destroy, pthread_rwlockattr_destroy) int @@ -624,10 +457,6 @@ pthread_rwlockattr_setpshared (pthread_rwlockattr_t *attr, int pshared) if (pshared != PTHREAD_PROCESS_PRIVATE && pshared != PTHREAD_PROCESS_SHARED) return EINVAL; - /* For now it is not possible to shared a conditional variable. */ - if (pshared != PTHREAD_PROCESS_PRIVATE) - return ENOSYS; - attr->__pshared = pshared; return 0; @@ -647,7 +476,6 @@ pthread_rwlockattr_setkind_np (pthread_rwlockattr_t *attr, int pref) { if (pref != PTHREAD_RWLOCK_PREFER_READER_NP && pref != PTHREAD_RWLOCK_PREFER_WRITER_NP - && pref != PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP && pref != PTHREAD_RWLOCK_DEFAULT_NP) return EINVAL; -- cgit v1.2.3