diff options
Diffstat (limited to 'nptl')
| -rw-r--r-- | nptl/Makefile | 2 | ||||
| -rw-r--r-- | nptl/pthread_mutex_timedlock.c | 3 | ||||
| -rw-r--r-- | nptl/tst-mutex-errorcheck.c | 61 |
3 files changed, 64 insertions, 2 deletions
diff --git a/nptl/Makefile b/nptl/Makefile index 6d3d71170b..dc3ccab991 100644 --- a/nptl/Makefile +++ b/nptl/Makefile @@ -288,7 +288,7 @@ tests = tst-typesizes \ tst-initializers1 $(addprefix tst-initializers1-,\ c89 gnu89 c99 gnu99 c11 gnu11) \ tst-bad-schedattr \ - tst-thread_local1 + tst-thread_local1 tst-mutex-errorcheck xtests = tst-setuid1 tst-setuid1-static tst-setuid2 \ tst-mutexpp1 tst-mutexpp6 tst-mutexpp10 test-srcs = tst-oddstacklimit diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c index 9055e11f8f..07f0901e52 100644 --- a/nptl/pthread_mutex_timedlock.c +++ b/nptl/pthread_mutex_timedlock.c @@ -89,7 +89,8 @@ pthread_mutex_timedlock (pthread_mutex_t *mutex, if (__glibc_unlikely (mutex->__data.__owner == id)) return EDEADLK; - /* FALLTHROUGH */ + /* Don't do lock elision on an error checking mutex. */ + goto simple; case PTHREAD_MUTEX_TIMED_NP: FORCE_ELISION (mutex, goto elision); diff --git a/nptl/tst-mutex-errorcheck.c b/nptl/tst-mutex-errorcheck.c new file mode 100644 index 0000000000..7b756112a9 --- /dev/null +++ b/nptl/tst-mutex-errorcheck.c @@ -0,0 +1,61 @@ +/* Check that error checking mutexes are not subject to lock elision. + Copyright (C) 2016 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <stdio.h> +#include <errno.h> +#include <time.h> +#include <pthread.h> + +static int +do_test (void) +{ + struct timespec tms = { 0 }; + pthread_mutex_t mutex; + pthread_mutexattr_t mutexattr; + int ret = 0; + + if (pthread_mutexattr_init (&mutexattr) != 0) + return 1; + if (pthread_mutexattr_settype (&mutexattr, PTHREAD_MUTEX_ERRORCHECK) != 0) + return 1; + + if (pthread_mutex_init (&mutex, &mutexattr) != 0) + return 1; + if (pthread_mutexattr_destroy (&mutexattr) != 0) + return 1; + + /* The call to pthread_mutex_timedlock erroneously enabled lock elision + on the mutex, which then triggered an assertion failure in + pthread_mutex_unlock. It would also defeat the error checking nature + of the mutex. */ + if (pthread_mutex_timedlock (&mutex, &tms) != 0) + return 1; + if (pthread_mutex_timedlock (&mutex, &tms) != EDEADLK) + { + printf ("Failed error checking on locked mutex\n"); + ret = 1; + } + + if (pthread_mutex_unlock (&mutex) != 0) + ret = 1; + + return ret; +} + +#define TEST_FUNCTION do_test () +#include "../test-skeleton.c" |