diff options
Diffstat (limited to 'nptl')
| -rw-r--r-- | nptl/pthread_join_common.c | 76 |
1 files changed, 18 insertions, 58 deletions
diff --git a/nptl/pthread_join_common.c b/nptl/pthread_join_common.c index 67d8e2b780..4293b072c8 100644 --- a/nptl/pthread_join_common.c +++ b/nptl/pthread_join_common.c @@ -32,55 +32,6 @@ cleanup (void *arg) atomic_compare_exchange_weak_acquire (&arg, &self, NULL); } -/* The kernel notifies a process which uses CLONE_CHILD_CLEARTID via futex - wake-up when the clone terminates. The memory location contains the - thread ID while the clone is running and is reset to zero by the kernel - afterwards. The kernel up to version 3.16.3 does not use the private futex - operations for futex wake-up when the clone terminates. */ -static int -clockwait_tid (pid_t *tidp, clockid_t clockid, - const struct __timespec64 *abstime) -{ - pid_t tid; - int ret; - - if (! valid_nanoseconds (abstime->tv_nsec)) - return EINVAL; - - /* Repeat until thread terminated. */ - while ((tid = *tidp) != 0) - { - struct __timespec64 rt; - - /* Get the current time. This can only fail if clockid is - invalid. */ - if (__glibc_unlikely (__clock_gettime64 (clockid, &rt))) - return EINVAL; - - /* Compute relative timeout. */ - rt.tv_sec = abstime->tv_sec - rt.tv_sec; - rt.tv_nsec = abstime->tv_nsec - rt.tv_nsec; - if (rt.tv_nsec < 0) - { - rt.tv_nsec += 1000000000; - --rt.tv_sec; - } - - /* Already timed out? */ - if (rt.tv_sec < 0) - return ETIMEDOUT; - - /* If *tidp == tid, wait until thread terminates or the wait times out. - The kernel up to version 3.16.3 does not use the private futex - operations for futex wake-up when the clone terminates. */ - ret = futex_timed_wait_cancel64 (tidp, tid, &rt, LLL_SHARED); - if (ret == -ETIMEDOUT || ret == -EOVERFLOW) - return -ret; - } - - return 0; -} - int __pthread_clockjoin_ex (pthread_t threadid, void **thread_return, clockid_t clockid, @@ -137,15 +88,24 @@ __pthread_clockjoin_ex (pthread_t threadid, void **thread_return, un-wait-ed for again. */ pthread_cleanup_push (cleanup, &pd->joinid); - if (abstime != NULL) - result = clockwait_tid (&pd->tid, clockid, abstime); - else - { - pid_t tid; - /* We need acquire MO here so that we synchronize with the - kernel's store to 0 when the clone terminates. (see above) */ - while ((tid = atomic_load_acquire (&pd->tid)) != 0) - lll_futex_wait_cancel (&pd->tid, tid, LLL_SHARED); + /* We need acquire MO here so that we synchronize with the + kernel's store to 0 when the clone terminates. (see above) */ + pid_t tid; + while ((tid = atomic_load_acquire (&pd->tid)) != 0) + { + /* The kernel notifies a process which uses CLONE_CHILD_CLEARTID via + futex wake-up when the clone terminates. The memory location + contains the thread ID while the clone is running and is reset to + zero by the kernel afterwards. The kernel up to version 3.16.3 + does not use the private futex operations for futex wake-up when + the clone terminates. */ + int ret = __futex_abstimed_wait_cancelable64 ( + (unsigned int *) &pd->tid, tid, clockid, abstime, LLL_SHARED); + if (ret == ETIMEDOUT || ret == EOVERFLOW) + { + result = ret; + break; + } } pthread_cleanup_pop (0); |