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author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2017-01-25 17:08:51 -0200 |
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committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2017-12-20 11:32:54 -0200 |
commit | 4735850f7a4f07f05ee9ff405238332f4bb3ab50 (patch) | |
tree | b16aba7381f9bc06cc2a903a36bd9c7d647e845c /nptl/pthread_join.c | |
parent | 8bfb461e20380dbc579f6dad4c54bb8a55afc82a (diff) | |
download | glibc-4735850f7a4f07f05ee9ff405238332f4bb3ab50.tar.gz glibc-4735850f7a4f07f05ee9ff405238332f4bb3ab50.tar.xz glibc-4735850f7a4f07f05ee9ff405238332f4bb3ab50.zip |
nptl: Consolidate pthread_{timed,try}join{_np}
This patch consolidates the pthread_join and gnu extensions to avoid code duplication. The function pthread_join, pthread_tryjoin_np, and pthread_timedjoin_np are now based on pthread_timedjoin_ex. It also fixes some inconsistencies on ESRCH, EINVAL, EDEADLK handling (where each implementation differs from each other) and also on clenup handler (which now always use a CAS). Checked on i686-linux-gnu and x86_64-linux-gnu. * nptl/pthreadP.h (__pthread_timedjoin_np): Define. * nptl/pthread_join.c (pthread_join): Use __pthread_timedjoin_np. * nptl/pthread_tryjoin.c (pthread_tryjoin): Likewise. * nptl/pthread_timedjoin.c (cleanup): Use CAS on argument setting. (pthread_timedjoin_np): Define internal symbol and common code from pthread_join. * sysdeps/unix/sysv/linux/i386/lowlevellock.h (__lll_timedwait_tid): Remove superflous checks. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (__lll_timedwait_tid): Likewise. Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Diffstat (limited to 'nptl/pthread_join.c')
-rw-r--r-- | nptl/pthread_join.c | 94 |
1 files changed, 1 insertions, 93 deletions
diff --git a/nptl/pthread_join.c b/nptl/pthread_join.c index afc8c379ca..47379a67a3 100644 --- a/nptl/pthread_join.c +++ b/nptl/pthread_join.c @@ -16,103 +16,11 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ -#include <errno.h> -#include <stdlib.h> - -#include <atomic.h> #include "pthreadP.h" -#include <stap-probe.h> - - -static void -cleanup (void *arg) -{ - /* If we already changed the waiter ID, reset it. The call cannot - fail for any reason but the thread not having done that yet so - there is no reason for a loop. */ - (void) atomic_compare_and_exchange_bool_acq ((struct pthread **) arg, NULL, - THREAD_SELF); -} - - int __pthread_join (pthread_t threadid, void **thread_return) { - struct pthread *pd = (struct pthread *) threadid; - - /* Make sure the descriptor is valid. */ - if (INVALID_NOT_TERMINATED_TD_P (pd)) - /* Not a valid thread handle. */ - return ESRCH; - - /* Is the thread joinable?. */ - if (IS_DETACHED (pd)) - /* We cannot wait for the thread. */ - return EINVAL; - - struct pthread *self = THREAD_SELF; - int result = 0; - - LIBC_PROBE (pthread_join, 1, threadid); - - /* During the wait we change to asynchronous cancellation. If we - are canceled the thread we are waiting for must be marked as - un-wait-ed for again. */ - pthread_cleanup_push (cleanup, &pd->joinid); - - /* Switch to asynchronous cancellation. */ - int oldtype = CANCEL_ASYNC (); - - if ((pd == self - || (self->joinid == pd - && (pd->cancelhandling - & (CANCELING_BITMASK | CANCELED_BITMASK | EXITING_BITMASK - | TERMINATED_BITMASK)) == 0)) - && !CANCEL_ENABLED_AND_CANCELED (self->cancelhandling)) - /* This is a deadlock situation. The threads are waiting for each - other to finish. Note that this is a "may" error. To be 100% - sure we catch this error we would have to lock the data - structures but it is not necessary. In the unlikely case that - two threads are really caught in this situation they will - deadlock. It is the programmer's problem to figure this - out. */ - result = EDEADLK; - /* Wait for the thread to finish. If it is already locked something - is wrong. There can only be one waiter. */ - else if (__builtin_expect (atomic_compare_and_exchange_bool_acq (&pd->joinid, - self, - NULL), 0)) - /* There is already somebody waiting for the thread. */ - result = EINVAL; - else - /* Wait for the child. */ - lll_wait_tid (pd->tid); - - - /* Restore cancellation mode. */ - CANCEL_RESET (oldtype); - - /* Remove the handler. */ - pthread_cleanup_pop (0); - - - if (__glibc_likely (result == 0)) - { - /* We mark the thread as terminated and as joined. */ - pd->tid = -1; - - /* Store the return value if the caller is interested. */ - if (thread_return != NULL) - *thread_return = pd->result; - - - /* Free the TCB. */ - __free_tcb (pd); - } - - LIBC_PROBE (pthread_join_ret, 3, threadid, result, pd->result); - - return result; + return __pthread_timedjoin_ex (threadid, thread_return, NULL, true); } weak_alias (__pthread_join, pthread_join) |