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2015-01-21Fix semaphore destruction (bug 12674).Carlos O'Donell
This commit fixes semaphore destruction by either using 64b atomic operations (where available), or by using two separate fields when only 32b atomic operations are available. In the latter case, we keep a conservative estimate of whether there are any waiting threads in one bit of the field that counts the number of available tokens, thus allowing sem_post to atomically both add a token and determine whether it needs to call futex_wake. See: https://sourceware.org/ml/libc-alpha/2014-12/msg00155.html
2003-06-19Make clear that futex_wake in sem_post gets passed the new value.Ulrich Drepper
2002-11-26Initial revisioncvs/initialUlrich Drepper
2002-11-26 Ulrich Drepper <drepper@redhat.com> * allocatestack.c (queue_stack): Don't remove stack from list here. Do it in the caller. Correct condition to prematurely terminate loop to free stacks. (__deallocate_stack): Remove stack from list here. 2002-11-26 Ulrich Drepper <drepper@redhat.com> * Makefile (tests): Add tst-stack1. * tst-stack1.c: New file. * allocatestack.c (allocate_stack): Initialize the TCB on a user provided stack. * pthread_attr_getstack.c: Return bottom of the thread area. 2002-11-25 Ulrich Drepper <drepper@redhat.com> * Makefile (libpthread-routines): Add pt-allocrtsig and pthread_kill_other_threads. * pt-allocrtsig.c: New file. * pthread_kill_other_threads.c: New file. * sysdeps/unix/sysv/linux/allocrtsig.c: Add additional aliases for all three functions. * sysdeps/unix/sysv/linux/Makefile (sysdep_routines): Remove allocrtsig. * sysdeps/unix/sysv/linux/Versions (libc:GLIBC_PRIVATE): Export __libc_current_sigrtmin_private, __libc_current_sigrtmax_private, and __libc_allocate_rtsig_private. * Versions (libpthread): Export pthread_kill_other_threads_np, __libc_current_sigrtmin, and __libc_current_sigrtmax. 2002-11-24 Ulrich Drepper <drepper@redhat.com> * allocatestack.c (allocate_stack): stackaddr in attribute points to the end of the stack. Adjust computations. When mprotect call fails dequeue stack and free it. * pthread_attr_setstack.c: Store top of the stack in stackaddr attribute. * pthread_getattr_np.c: Likewise. * descr.h (IS_DETACHED): Add some more parenthesis to prevent surprises. 2002-11-23 Ulrich Drepper <drepper@redhat.com> * sysdeps/pthread/pthread.h (pthread_self): __THROW must come before attribute definitions. Patch by Luca Barbieri <ldb@ldb.ods.org>. 2002-11-22 Ulrich Drepper <drepper@redhat.com> * pthread_getspecific.c: Optimize access to first 2nd-level array. * pthread_setspecific.c: Likewise. 2002-11-21 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/i386/createthread.c: Remove CLONE_ flags definitions. Get them from the official place. * sysdeps/unix/sysv/linux/i386/fork.c: Likewise. * sysdeps/unix/sysv/linux/i386/createthread.c: Update CLONE_* flags. Use new CLONE_ flags in clone() calls. * sysdeps/unix/sysv/linux/fork.c: Use ARCH_FORK to actually fork. * sysdeps/unix/sysv/linux/i386/fork.c: New file. * Versions: Add pthread_* functions for libc. * forward.c: New file. * sysdeps/pthread/Makefile (libpthread-sysdeps_routines): Add errno-loc. * herrno.c: New file. * res.c: New file. * Makefile (libpthread-routines): Remove sem_post, sem_wait, sem_trywait, and sem_timedwait. Add herrno and res. * sem_init.c: Don't initialize lock and waiters members. * sem_open.c: Likewise. * sem_post.c: Removed. * sem_wait.c: Removed. * sem_trywait.c: Removed. * sem_timedwait.c: Removed. * sysdeps/unix/sysv/linux/i386/i486/lowlevelsem.S: Complete rewrite. Includes full implementations of sem_post, sem_wait, sem_trywait, and sem_timedwait. * sysdeps/unix/sysv/linux/i386/lowlevelsem.h (lll_sem_post): Adjust for new implementation. * sysdeps/unix/sysv/linux/internaltypes.h (struct sem): Remove lock and waiters fields. * tst-sem3.c: Improve error message. * tst-signal3.c: Likewise. * init.c (__pthread_initialize_minimal): Use set_tid_address syscall to tell the kernel about the termination futex and to initialize tid member. Don't initialize main_thread. * descr.h (struct pthread): Remove main_thread member. * cancelllation.c (__do_cancel): Remove code handling main thread. The main thread is not special anymore. * allocatestack.c (__reclaim_stacks): Mark stacks as unused. Add size of the stacks to stack_cache_actsize. * pt-readv.c: Add missing "defined". * pt-sigwait.c: Likewise. * pt-writev.c: Likewise. 2002-11-09 Ulrich Drepper <drepper@redhat.com> * Versions: Export __connect from libpthread. Patch by Luca Barbieri <ldb@ldb.ods.org>. * Makefile (libpthread-routines): Add pt-raise. * sysdeps/unix/sysv/linux/raise.c: New file. * sysdeps/unix/sysv/linux/pt-raise.c: New file. * sysdeps/generic/pt-raise.c: New file. * pthread_cond_init.c: Initialize all data elements of the condvar structure. Patch by Luca Barbieri <ldb@ldb.ods.org>. * pthread_attr_init.c: Actually implement 2.0 compatibility version. * pthread_create.c: Likewise. * Makefile (tests): Add tst-key1, tst-key2, tst-key3. * tst-key1.c: New file. * tst-key2.c: New file. * tst-key3.c: New file. * Versions: Export pthread_detach for version GLIBC_2.0. Reported by Saurabh Desai <sdesai@austin.ibm.com>. 2002-11-08 Ulrich Drepper <drepper@redhat.com> * pthread_key_create.c: Terminate search after an unused key was found. Patch by Luca Barbieri <ldb@ldb.ods.org>. * sysdeps/unix/sysv/linux/i386/pthread_once.S: Return zero. Patch by Luca Barbieri <ldb@ldb.ods.org>. 2002-10-10 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/i386/i486/lowlevelsem.S: Use slow generic dynamic lookup for errno in PIC. * allocatestack.c (get_cached_stack): Rearrange code slightly to release the stack lock as soon as possible. Call _dl_allocate_tls_init for TCB from the cache to re-initialize the static TLS block. (allocate_stack): Call _dl_allocate_tls_init for user-provided stack. * cancellation.c: Renamed from cancelation.c. * Makefile: Adjust accordingly. * pthreadP.h (CANCELLATION_P): Renamed from CANCELATION_P. * cleanup_defer.c: Use CANCELLATION_P. * pthread_testcancel.c: Likewise. * descr.h: Fix spelling in comments. * init.c: Likewise. * pthread_getattr_np.c: Likewise. * pthread_getschedparam.c: Likewise. * pthread_setschedparam.c: Likewise. * Versions: Likewise. * pt-pselect.c: New file. * Makefile (libpthread-routines): Add pt-pselect. * Versions: Add pselect. * tst-cancel4.c: New file. * Makefile (tests): Add tst-cancel4. 2002-10-09 Ulrich Drepper <drepper@redhat.com> * pthread_mutex_lock.c: Always record lock ownership. * pthread_mutex_timedlock.c: Likewise. * pthread_mutex_trylock.c: Likewise. * pt-readv.c: New file. * pt-writev.c: New file. * pt-creat.c: New file. * pt-msgrcv.c: New file. * pt-msgsnd.c: New file. * pt-poll.c: New file. * pt-select.c: New file. * pt-sigpause.c: New file. * pt-sigsuspend.c: New file. * pt-sigwait.c: New file. * pt-sigwaitinfo.c: New file. * pt-waitid.c: New file. * Makefile (libpthread-routines): Add pt-readv, pt-writev, pt-creat, pt-msgrcv, pt-msgsnd, pt-poll, pt-select, pt-sigpause, pt-sigsuspend, pt-sigwait, pt-sigwaitinfo, and pt-waitid. * Versions: Add all the new functions. * tst-exit1.c: New file. * Makefile (tests): Add tst-exit1. * sem_timedwait.c: Minor optimization for more optimal fastpath. 2002-10-08 Ulrich Drepper <drepper@redhat.com> * pt-fcntl.c: Only enable asynchronous cancellation for F_SETLKW. * pthread_join.c: Enable asynchronous cancellation around lll_wait_tid call. pthread_join is an official cancellation point. * pthread_timedjoin.c: Likewise. * pthread_cond_wait.c: Revert order in which internal lock are dropped and the condvar's mutex are retrieved. * pthread_cond_timedwait.c: Likewise. Reported by dice@saros.East.Sun.COM. 2002-10-07 Ulrich Drepper <drepper@redhat.com> * pthreadP.h: Cut out all type definitions and move them... * sysdeps/unix/sysv/linux/internaltypes.h: ...here. New file. * pthreadP.h: Include <internaltypes.h>. * sysdeps/unix/sysv/linux/i386/lowlevelsem.h (lll_sem_post): Little performance tweaks. * sem_trywait.c: Shuffle #includes around to get right order. * sem_timedwait.c: Likewise. * sem_post.c: Likewise. * sem_wait.c: Likewise. * nptl 0.3 released. * Makefile (tests): Add tst-signal3. * tst-signal3.c: New file. 2002-10-05 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/i386/lowlevelsem.h: Tell the compiler that the asms modify the sem object. (__lll_sem_timedwait): Now takes struct sem* as first parameter. * sysdeps/unix/sysv/linux/i386/bits/semaphore.h (sem_t): Don't expose the actual members. * pthreadP.h (struct sem): New type. Actual semaphore type. * semaphoreP.h: Include pthreadP.h. * sem_getvalue.c: Adjust to sem_t change. * sem_init.c: Likewise. * sem_open.c: Likewise. * sem_post.c: Likewise. * sem_timedwait.c: Likewise. * sem_trywait.c: Likewise. * sem_wait.c: Likewise. 2002-10-04 Ulrich Drepper <drepper@redhat.com> * Makefile (tests): Add tst-basic2, tst-exec1, tst-exec3, tst-exec3. * tst-basic2.c: New file. * tst-exec1.c: New file. * tst-exec2.c: New file. * tst-exec3.c: New file. * tst-fork1.c: Remove extra */. * nptl 0.2 released. The API for IA-32 is complete.