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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:15:05 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:15:05 +0000
commit46651ce6fe013220ed397add242004d764fc0153 (patch)
tree6e5299f990f88e60174a1d3ae6e48eedd2688b2b /src/port/pthread_barrier_wait.c
parentInitial commit. (diff)
downloadpostgresql-14-upstream.tar.xz
postgresql-14-upstream.zip
Adding upstream version 14.5.upstream/14.5upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/port/pthread_barrier_wait.c')
-rw-r--r--src/port/pthread_barrier_wait.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/src/port/pthread_barrier_wait.c b/src/port/pthread_barrier_wait.c
new file mode 100644
index 0000000..8282cc5
--- /dev/null
+++ b/src/port/pthread_barrier_wait.c
@@ -0,0 +1,77 @@
+/*-------------------------------------------------------------------------
+ *
+ * pthread_barrier_wait.c
+ * Implementation of pthread_barrier_t support for platforms lacking it.
+ *
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/port/pthread_barrier_wait.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "c.h"
+
+#include "port/pg_pthread.h"
+
+int
+pthread_barrier_init(pthread_barrier_t *barrier, const void *attr, int count)
+{
+ int error;
+
+ barrier->sense = false;
+ barrier->count = count;
+ barrier->arrived = 0;
+ if ((error = pthread_cond_init(&barrier->cond, NULL)) != 0)
+ return error;
+ if ((error = pthread_mutex_init(&barrier->mutex, NULL)) != 0)
+ {
+ pthread_cond_destroy(&barrier->cond);
+ return error;
+ }
+
+ return 0;
+}
+
+int
+pthread_barrier_wait(pthread_barrier_t *barrier)
+{
+ bool initial_sense;
+
+ pthread_mutex_lock(&barrier->mutex);
+
+ /* We have arrived at the barrier. */
+ barrier->arrived++;
+ Assert(barrier->arrived <= barrier->count);
+
+ /* If we were the last to arrive, release the others and return. */
+ if (barrier->arrived == barrier->count)
+ {
+ barrier->arrived = 0;
+ barrier->sense = !barrier->sense;
+ pthread_mutex_unlock(&barrier->mutex);
+ pthread_cond_broadcast(&barrier->cond);
+
+ return PTHREAD_BARRIER_SERIAL_THREAD;
+ }
+
+ /* Wait for someone else to flip the sense. */
+ initial_sense = barrier->sense;
+ do
+ {
+ pthread_cond_wait(&barrier->cond, &barrier->mutex);
+ } while (barrier->sense == initial_sense);
+
+ pthread_mutex_unlock(&barrier->mutex);
+
+ return 0;
+}
+
+int
+pthread_barrier_destroy(pthread_barrier_t *barrier)
+{
+ pthread_cond_destroy(&barrier->cond);
+ pthread_mutex_destroy(&barrier->mutex);
+ return 0;
+}