BUG/MEDIUM: threads: fix the no-thread case after the change to the sync point
In commit 0c026f4 ("MINOR: threads: add more consistency between certain
variables in no-thread case"), we ensured that we don't have all_threads_mask
zeroed anymore. But one test was missed for the write() to the sync pipe.
This results in a situation where when running single-threaded, once a
server status changes, a wake-up message is written to the pipe and never
consumed, showing a 100% CPU usage.
No backport is needed.
diff --git a/src/hathreads.c b/src/hathreads.c
index 69dcab9..16284be 100644
--- a/src/hathreads.c
+++ b/src/hathreads.c
@@ -70,7 +70,7 @@
*/
void thread_want_sync()
{
- if (all_threads_mask) {
+ if (all_threads_mask & (all_threads_mask - 1)) {
if (threads_want_sync & tid_bit)
return;
if (HA_ATOMIC_OR(&threads_want_sync, tid_bit) == tid_bit)