diff options
| -rw-r--r-- | ChangeLog | 15 | ||||
| -rw-r--r-- | nptl/Makefile | 2 | ||||
| -rw-r--r-- | nptl/pthread_mutex_lock.c | 13 | ||||
| -rw-r--r-- | nptl/pthread_mutex_timedlock.c | 13 | ||||
| -rw-r--r-- | nptl/tst-mutex7.c | 45 | ||||
| -rw-r--r-- | nptl/tst-mutex7robust.c | 7 |
6 files changed, 73 insertions, 22 deletions
diff --git a/ChangeLog b/ChangeLog index 4cec993f99..5368e15fb7 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,4 +1,17 @@ -2017-07-23 Nathan Rossi <nathan@nathanrossi.com> +2017-07-29 Torvald Riegel <triegel@redhat.com> + Carlos O'Donell <carlos@redhat.com> + + [BZ 21778] + * nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Update + oldval if the CAS fails. + * nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full): Likewise. + * nptl/tst-mutex7.c: Add comments explaining template test. + (ROBUST, DELAY_NSEC, ROUNDS, N): New. + (tf, do_test): Use them. + * nptl/tst-mutex7robust.c: New file. + * nptl/Makefile (tests): Add new test. + +2017-07-28 Nathan Rossi <nathan@nathanrossi.com> [BZ #21779] * sysdeps/unix/sysv/linux/microblaze/pt-vfork.S: Branch using PLT. diff --git a/nptl/Makefile b/nptl/Makefile index 7e54684a36..5cb1bb2c3d 100644 --- a/nptl/Makefile +++ b/nptl/Makefile @@ -230,7 +230,7 @@ LDLIBS-tst-thread_local1 = -lstdc++ tests = tst-attr1 tst-attr2 tst-attr3 tst-default-attr \ tst-mutex1 tst-mutex2 tst-mutex3 tst-mutex4 tst-mutex5 tst-mutex6 \ - tst-mutex7 tst-mutex9 tst-mutex5a tst-mutex7a \ + tst-mutex7 tst-mutex9 tst-mutex5a tst-mutex7a tst-mutex7robust \ tst-mutexpi1 tst-mutexpi2 tst-mutexpi3 tst-mutexpi4 tst-mutexpi5 \ tst-mutexpi5a tst-mutexpi6 tst-mutexpi7 tst-mutexpi7a \ tst-mutexpi9 \ diff --git a/nptl/pthread_mutex_lock.c b/nptl/pthread_mutex_lock.c index b76475bc63..8c485035eb 100644 --- a/nptl/pthread_mutex_lock.c +++ b/nptl/pthread_mutex_lock.c @@ -197,11 +197,14 @@ __pthread_mutex_lock_full (pthread_mutex_t *mutex) { /* Try to acquire the lock through a CAS from 0 (not acquired) to our TID | assume_other_futex_waiters. */ - if (__glibc_likely ((oldval == 0) - && (atomic_compare_and_exchange_bool_acq - (&mutex->__data.__lock, - id | assume_other_futex_waiters, 0) == 0))) - break; + if (__glibc_likely (oldval == 0)) + { + oldval + = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, + id | assume_other_futex_waiters, 0); + if (__glibc_likely (oldval == 0)) + break; + } if ((oldval & FUTEX_OWNER_DIED) != 0) { diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c index be5338178f..d5ec3141f3 100644 --- a/nptl/pthread_mutex_timedlock.c +++ b/nptl/pthread_mutex_timedlock.c @@ -154,11 +154,14 @@ __pthread_mutex_timedlock (pthread_mutex_t *mutex, { /* Try to acquire the lock through a CAS from 0 (not acquired) to our TID | assume_other_futex_waiters. */ - if (__glibc_likely ((oldval == 0) - && (atomic_compare_and_exchange_bool_acq - (&mutex->__data.__lock, - id | assume_other_futex_waiters, 0) == 0))) - break; + if (__glibc_likely (oldval == 0)) + { + oldval + = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, + id | assume_other_futex_waiters, 0); + if (__glibc_likely (oldval == 0)) + break; + } if ((oldval & FUTEX_OWNER_DIED) != 0) { diff --git a/nptl/tst-mutex7.c b/nptl/tst-mutex7.c index a11afdba5e..08fe251eeb 100644 --- a/nptl/tst-mutex7.c +++ b/nptl/tst-mutex7.c @@ -22,25 +22,41 @@ #include <stdlib.h> #include <time.h> - +/* This test is a template for other tests to use. Other tests define + the following macros to change the behaviour of the template test. + The test is very simple, it configures N threads given the parameters + below and then proceeds to go through mutex lock and unlock + operations in each thread as described before for the thread + function. */ #ifndef TYPE # define TYPE PTHREAD_MUTEX_DEFAULT #endif - +#ifndef ROBUST +# define ROBUST PTHREAD_MUTEX_STALLED +#endif +#ifndef DELAY_NSEC +# define DELAY_NSEC 11000 +#endif +#ifndef ROUNDS +# define ROUNDS 1000 +#endif +#ifndef N +# define N 100 +#endif static pthread_mutex_t lock; - -#define ROUNDS 1000 -#define N 100 - - +/* Each thread locks and the subsequently unlocks the lock, yielding + the smallest critical section possible. After the unlock the thread + waits DELAY_NSEC nanoseconds before doing the lock and unlock again. + Every thread does this ROUNDS times. The lock and unlock are + checked for errors. */ static void * tf (void *arg) { int nr = (long int) arg; int cnt; - struct timespec ts = { .tv_sec = 0, .tv_nsec = 11000 }; + struct timespec ts = { .tv_sec = 0, .tv_nsec = DELAY_NSEC }; for (cnt = 0; cnt < ROUNDS; ++cnt) { @@ -56,13 +72,16 @@ tf (void *arg) return (void *) 1l; } - nanosleep (&ts, NULL); + if ((ts.tv_sec > 0) || (ts.tv_nsec > 0)) + nanosleep (&ts, NULL); } return NULL; } - +/* Setup and run N threads, where each thread does as described + in the above thread function. The threads are given a minimal 1MiB + stack since they don't do anything between the lock and unlock. */ static int do_test (void) { @@ -80,6 +99,12 @@ do_test (void) exit (1); } + if (pthread_mutexattr_setrobust (&a, ROBUST) != 0) + { + puts ("mutexattr_setrobust failed"); + exit (1); + } + #ifdef ENABLE_PI if (pthread_mutexattr_setprotocol (&a, PTHREAD_PRIO_INHERIT) != 0) { diff --git a/nptl/tst-mutex7robust.c b/nptl/tst-mutex7robust.c new file mode 100644 index 0000000000..8221a61d29 --- /dev/null +++ b/nptl/tst-mutex7robust.c @@ -0,0 +1,7 @@ +/* Bug 21778: Fix oversight in robust mutex lock acquisition. */ +#define TYPE PTHREAD_MUTEX_NORMAL +#define ROBUST PTHREAD_MUTEX_ROBUST +#define DELAY_NSEC 0 +#define ROUNDS 1000 +#define N 32 +#include "tst-mutex7.c" |