From: Willy Tarreau <w@1wt.eu>
Date: Tue, 30 Jun 2020 09:19:23 +0000 (+0200)
Subject: MINOR: mux-fcgi: avoid taking the toremove_lock in on dying tasks
X-Git-Tag: v2.2-dev12~44
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=60814ffe8188ddd91fcdd6981a570e0d3107f60b;p=thirdparty%2Fhaproxy.git

MINOR: mux-fcgi: avoid taking the toremove_lock in on dying tasks

If the owning task is already dying (context was destroyed by fcgi_takeover)
there's no point taking the lock then removing it later since all the code
in between is conditionned by a non-null context. Let's simplify this.
---

diff --git a/src/mux_fcgi.c b/src/mux_fcgi.c
index 0e3ab3f1ad..b09ad566c2 100644
--- a/src/mux_fcgi.c
+++ b/src/mux_fcgi.c
@@ -3084,26 +3084,28 @@ static struct task *fcgi_timeout_task(struct task *t, void *context, unsigned sh
 
 	TRACE_ENTER(FCGI_EV_FCONN_WAKE, (fconn ? fconn->conn : NULL));
 
-	if (!expired && fconn) {
-		TRACE_DEVEL("leaving (not expired)", FCGI_EV_FCONN_WAKE, fconn->conn);
-		return t;
-	}
+	if (fconn) {
+		if (!expired) {
+			TRACE_DEVEL("leaving (not expired)", FCGI_EV_FCONN_WAKE, fconn->conn);
+			return t;
+		}
 
-	/* We're about to destroy the connection, so make sure nobody attempts
-	 * to steal it from us.
-	 */
-	HA_SPIN_LOCK(OTHER_LOCK, &idle_conns[tid].toremove_lock);
+		/* We're about to destroy the connection, so make sure nobody attempts
+		 * to steal it from us.
+		 */
+		HA_SPIN_LOCK(OTHER_LOCK, &idle_conns[tid].toremove_lock);
 
-	if (fconn && fconn->conn->flags & CO_FL_LIST_MASK)
-		MT_LIST_DEL(&fconn->conn->list);
+		if (fconn->conn->flags & CO_FL_LIST_MASK)
+			MT_LIST_DEL(&fconn->conn->list);
 
-	/* Somebody already stole the connection from us, so we should not
-	 * free it, we just have to free the task.
-	 */
-	if (!t->context)
-		fconn = NULL;
+		/* Somebody already stole the connection from us, so we should not
+		 * free it, we just have to free the task.
+		 */
+		if (!t->context)
+			fconn = NULL;
 
-	HA_SPIN_UNLOCK(OTHER_LOCK, &idle_conns[tid].toremove_lock);
+		HA_SPIN_UNLOCK(OTHER_LOCK, &idle_conns[tid].toremove_lock);
+	}
 
 	task_destroy(t);