BUG/MEDIUM: threads: Fix the exit condition of the thread barrier
In thread_sync_barrier, we exit when all threads have set their own bit in the
barrier mask. It is done by comparing it to all_threads_mask. But we must not
use a simple equality to do so, becaue all_threads_mask may change. Since commit
ba86c6c25 ("MINOR: threads: Be sure to remove threads from all_threads_mask on
exit"), when a thread exit, its bit is removed from all_threads_mask. Instead,
we must use a bitwise AND to test is all bits of all_threads_mask are set.
This also requires that all_threads_mask is set to volatile if we want to
catch changes.
This patch must be backported in 1.8.
diff --git a/include/common/hathreads.h b/include/common/hathreads.h
index 5c4ceca..274f988 100644
--- a/include/common/hathreads.h
+++ b/include/common/hathreads.h
@@ -260,7 +260,7 @@
int thread_no_sync(void);
int thread_need_sync(void);
-extern unsigned long all_threads_mask;
+extern volatile unsigned long all_threads_mask;
#define ha_sigmask(how, set, oldset) pthread_sigmask(how, set, oldset)