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* robust mutexes: Fix broken x86 assembly by removing itTorvald Riegel2017-01-131-232/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | lll_robust_unlock on i386 and x86_64 first sets the futex word to FUTEX_WAITERS|0 before calling __lll_unlock_wake, which will set the futex word to 0. If the thread is killed between these steps, then the futex word will be FUTEX_WAITERS|0, and the kernel (at least current upstream) will not set it to FUTEX_OWNER_DIED|FUTEX_WAITERS because 0 is not equal to the TID of the crashed thread. The lll_robust_lock assembly code on i386 and x86_64 is not prepared to deal with this case because the fastpath tries to only CAS 0 to TID and not FUTEX_WAITERS|0 to TID; the slowpath simply waits until it can CAS 0 to TID or the futex_word has the FUTEX_OWNER_DIED bit set. This issue is fixed by removing the custom x86 assembly code and using the generic C code instead. However, instead of adding more duplicate code to the custom x86 lowlevellock.h, the code of the lll_robust* functions is inlined into the single call sites that exist for each of these functions in the pthread_mutex_* functions. The robust mutex paths in the latter have been slightly reorganized to make them simpler. This patch is meant to be easy to backport, so C11-style atomics are not used. [BZ #20985] * nptl/Makefile: Adapt. * nptl/pthread_mutex_cond_lock.c (LLL_ROBUST_MUTEX_LOCK): Remove. (LLL_ROBUST_MUTEX_LOCK_MODIFIER): New. * nptl/pthread_mutex_lock.c (LLL_ROBUST_MUTEX_LOCK): Remove. (LLL_ROBUST_MUTEX_LOCK_MODIFIER): New. (__pthread_mutex_lock_full): Inline lll_robust* functions and adapt. * nptl/pthread_mutex_timedlock.c (pthread_mutex_timedlock): Inline lll_robust* functions and adapt. * nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_full): Likewise. * sysdeps/nptl/lowlevellock.h (__lll_robust_lock_wait, __lll_robust_lock, lll_robust_cond_lock, __lll_robust_timedlock_wait, __lll_robust_timedlock, __lll_robust_unlock): Remove. * sysdeps/unix/sysv/linux/i386/lowlevellock.h (lll_robust_lock, lll_robust_cond_lock, lll_robust_timedlock, lll_robust_unlock): Remove. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (lll_robust_lock, lll_robust_cond_lock, lll_robust_timedlock, lll_robust_unlock): Remove. * sysdeps/unix/sysv/linux/sparc/lowlevellock.h (__lll_robust_lock_wait, __lll_robust_lock, lll_robust_cond_lock, __lll_robust_timedlock_wait, __lll_robust_timedlock, __lll_robust_unlock): Remove. * nptl/lowlevelrobustlock.c: Remove file. * nptl/lowlevelrobustlock.sym: Likewise. * sysdeps/unix/sysv/linux/i386/lowlevelrobustlock.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevelrobustlock.S: Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Move sysdeps/unix/sysv/linux/i386/i486/*.? to i386H.J. Lu2015-09-301-0/+232
Since glibc doesn't support i386 any more, we can move sysdeps/unix/sysv/linux/i386/i486/*.? to i386. [BZ #19006] * sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S: Moved to ... * sysdeps/unix/sysv/linux/i386/libc-lowlevellock.S: Here. * sysdeps/unix/sysv/linux/i386/i486/lll_timedlock_wait.c: Moved to ... * sysdeps/unix/sysv/linux/i386/lll_timedlock_wait.c: Here. * sysdeps/unix/sysv/linux/i386/i486/lll_timedwait_tid.c: Moved to ... * sysdeps/unix/sysv/linux/i386/lll_timedwait_tid.c: Here. * sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S: Moved to ... * sysdeps/unix/sysv/linux/i386/lowlevellock.S: Here. * sysdeps/unix/sysv/linux/i386/i486/lowlevelrobustlock.S: Moved to ... * sysdeps/unix/sysv/linux/i386/lowlevelrobustlock.S: Here. * sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S: Moved to ... * sysdeps/unix/sysv/linux/i386/pthread_barrier_wait.S: Here. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_broadcast.S: Moved to ... * sysdeps/unix/sysv/linux/i386/pthread_cond_broadcast.S: Here. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S: Moved to ... * sysdeps/unix/sysv/linux/i386/pthread_cond_signal.S: Here. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S: Moved to ... * sysdeps/unix/sysv/linux/i386/pthread_cond_timedwait.S: Here. * sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S: Moved to ... * sysdeps/unix/sysv/linux/i386/pthread_cond_wait.S: Here. * sysdeps/unix/sysv/linux/i386/i586/libc-lowlevellock.S: Removed. * sysdeps/unix/sysv/linux/i386/i586/lll_timedlock_wait.c: Likewise. * sysdeps/unix/sysv/linux/i386/i586/lll_timedwait_tid.c: Likewise. * sysdeps/unix/sysv/linux/i386/i586/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/lowlevelrobustlock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_barrier_wait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_broadcast.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_signal.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_timedwait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i586/pthread_cond_wait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/libc-lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/lll_timedlock_wait.c: Likewise. * sysdeps/unix/sysv/linux/i386/i686/lll_timedwait_tid.c: Likewise. * sysdeps/unix/sysv/linux/i386/i686/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/lowlevelrobustlock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_barrier_wait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_broadcast.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_signal.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_wait.S: Likewise. * sysdeps/unix/sysv/linux/i386/i686/pthread_cond_timedwait.S: Replace ../i486/pthread_cond_timedwait.S with ../pthread_cond_timedwait.S.