From: Olivier Houchard <cognet@ci0.org>
Date: Tue, 24 Sep 2019 12:55:28 +0000 (+0200)
Subject: BUG/MEDIUM: tasklets: Make sure we're waking the target thread if it sleeps.
X-Git-Tag: v2.1-dev2~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bba1a263c5831436196d1c6fbd5f771d659b34a7;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: tasklets: Make sure we're waking the target thread if it sleeps.

Now that we can wake tasklet for other threads, make sure that if the thread
is sleeping, we wake it up, or the tasklet won't be executed until it's
done sleeping.
That also means that, before going to sleep, and after we put our bit
in sleeping_thread_mask, we have to check that nobody added a tasklet for
us, just checking for global_tasks_mask isn't enough anymore.
---

diff --git a/include/proto/task.h b/include/proto/task.h
index 511d3cd6ca..261ee9c5df 100644
--- a/include/proto/task.h
+++ b/include/proto/task.h
@@ -38,6 +38,8 @@
 #include <types/global.h>
 #include <types/task.h>
 
+#include <proto/fd.h>
+
 /* Principle of the wait queue.
  *
  * We want to be able to tell whether an expiration date is before of after the
@@ -226,8 +228,13 @@ static inline struct task *task_unlink_rq(struct task *t)
 
 static inline void tasklet_wakeup(struct tasklet *tl)
 {
-	if (MT_LIST_ADDQ(&task_per_thread[tl->tid].task_list, &tl->list) == 1)
+	if (MT_LIST_ADDQ(&task_per_thread[tl->tid].task_list, &tl->list) == 1) {
 		_HA_ATOMIC_ADD(&tasks_run_queue, 1);
+		if (sleeping_thread_mask & (1 << tl->tid)) {
+			_HA_ATOMIC_AND(&sleeping_thread_mask, ~(1 << tl->tid));
+			wake_thread(tl->tid);
+		}
+	}
 
 }
 
diff --git a/src/haproxy.c b/src/haproxy.c
index f577104f55..05b0afa32f 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -2634,7 +2634,7 @@ static void run_poll_loop()
 		else {
 			_HA_ATOMIC_OR(&sleeping_thread_mask, tid_bit);
 			__ha_barrier_atomic_store();
-			if (global_tasks_mask & tid_bit) {
+			if ((global_tasks_mask & tid_bit) || thread_has_tasks()) {
 				activity[tid].wake_tasks++;
 				_HA_ATOMIC_AND(&sleeping_thread_mask, ~tid_bit);
 			} else