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* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* nptl: Fix sem_wait and sem_timedwait cancellation (BZ#18243)Adhemerval Zanella2016-09-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes both sem_wait and sem_timedwait cancellation point for uncontended case. In this scenario only atomics are involved and thus the futex cancellable call is not issue and a pending cancellation signal is not handled. The fix is straighforward by calling pthread_testcancel is both function start. Although it would be simpler to call CANCELLATION_P directly, I decided to add an internal pthread_testcancel alias and use it to export less internal implementation on such function. A possible change on how pthread_testcancel is internally implemented would lead to either continue to force use CANCELLATION_P or to adjust its every use. GLIBC testcase also does have tests for uncontended cases, test-cancel12 and test-cancel14.c, however both are flawed by adding another cancellation point just after thread pthread_cleanup_pop: 47 static void * 48 tf (void *arg) 49 { 50 pthread_cleanup_push (cleanup, NULL); 51 52 int e = pthread_barrier_wait (&bar); 53 if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD) 54 { 55 puts ("tf: 1st barrier_wait failed"); 56 exit (1); 57 } 58 59 /* This call should block and be cancelable. */ 60 sem_wait (&sem); 61 62 pthread_cleanup_pop (0); 63 64 puts ("sem_wait returned"); 65 66 return NULL; 67 } So sem_{timed}wait does not act on cancellation, pthread_cleanup_pop executes 'cleanup' and then 'puts' acts on cancellation. Since pthread_cleanup_pop removed the clean-up handler, it will ran only once and thus it won't accuse an error to indicate sem_wait has not acted on the cancellation signal. This patch also fixes this behavior by removing the cancellation point 'puts'. It also adds some cleanup on all sem_{timed}wait cancel tests. It partially fixes BZ #18243. Checked on x86_64. [BZ #18243] * nptl/pthreadP.h (__pthread_testcancel): Add prototype and hidden_proto. * nptl/pthread_testcancel.c (pthread_cancel): Add internal aliais definition. * nptl/sem_timedwait.c (sem_timedwait): Add cancellation check for uncontended case. * nptl/sem_wait.c (__new_sem_wait): Likewise. * nptl/tst-cancel12.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise. * nptl/tst-cancel13.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise. * nptl/tst-cancel14.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise. * nptl/tst-cancel15.c (cleanup): Remove wrong cancellation point. (tf): Fix check for uncontended case. (do_test): Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Fix semaphore destruction (bug 12674).Carlos O'Donell2015-01-211-88/+8
| | | | | | | | | | | | | 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
* Update copyright dates with scripts/update-copyrights.Joseph Myers2015-01-021-1/+1
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* NPTL: Add some missing #include'sRoland McGrath2014-10-201-0/+1
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* Get rid of nptl/sysdeps/ entirely!Roland McGrath2014-07-071-0/+116