BUG/MINOR: threads: Handle nbthread == MAX_THREADS.
If nbthread is MAX_THREADS, the shift operation needed to compute
all_threads_mask fails in thread_sync_init(). Instead pass a number
of threads to this function and let it compute the mask without
overflowing.
This should be backported to 1.8.
diff --git a/src/hathreads.c b/src/hathreads.c
index fa9993b..c0c5956 100644
--- a/src/hathreads.c
+++ b/src/hathreads.c
@@ -37,11 +37,11 @@
struct lock_stat lock_stats[LOCK_LABELS];
#endif
-/* Initializes the sync point. It creates a pipe used by threads to wakup all
- * others when a sync is requested. It also initialize the mask of all create
+/* Initializes the sync point. It creates a pipe used by threads to wake up all
+ * others when a sync is requested. It also initializes the mask of all created
* threads. It returns 0 on success and -1 if an error occurred.
*/
-int thread_sync_init(unsigned long mask)
+int thread_sync_init(int nbthread)
{
int rfd;
@@ -52,7 +52,9 @@
fcntl(rfd, F_SETFL, O_NONBLOCK);
fd_insert(rfd, thread_sync_io_handler, thread_sync_io_handler, MAX_THREADS_MASK);
- all_threads_mask = mask;
+ /* we proceed like this to be sure never to overflow the left shift */
+ all_threads_mask = 1UL << (nbthread - 1);
+ all_threads_mask |= all_threads_mask - 1;
return 0;
}