From d8b7a4701d1b01db5b0efc1de4227acfa9604d0f Mon Sep 17 00:00:00 2001
From: Olivier Houchard <ohouchard@haproxy.com>
Date: Thu, 16 Aug 2018 19:03:02 +0200
Subject: [PATCH] BUG/MEDIUM: tasks: Don't insert in the global rqueue if
 nbthread == 1

Make sure we don't insert a task in the global run queue if nbthread == 1,
as, as an optimisation, we avoid reading from it if nbthread == 1.
---
 src/task.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/task.c b/src/task.c
index de097baf7..e357bc169 100644
--- a/src/task.c
+++ b/src/task.c
@@ -395,7 +395,8 @@ void process_runnable_tasks()
 			state = HA_ATOMIC_AND(&t->state, ~TASK_RUNNING);
 			if (state)
 #ifdef USE_THREAD
-				__task_wakeup(t, (t->thread_mask == tid_bit) ?
+				__task_wakeup(t, (t->thread_mask == tid_bit ||
+				    global.nbthread == 1) ?
 				    &rqueue_local[tid] : &rqueue);
 #else
 				__task_wakeup(t, &rqueue_local[tid]);