linux-kernel - [PATCH 1/7] Avoid taking rq lock in wake_priority

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20061028024117.10809.74875.sendpatchset@schroedinger.engr.sgi.com>
Date:	Fri, 27 Oct 2006 19:41:17 -0700 (PDT)
From:	Christoph Lameter <clameter@....com>
To:	akpm@...l.org
Cc:	Peter Williams <pwil3058@...pond.net.au>,
	linux-kernel@...r.kernel.org,
	Nick Piggin <nickpiggin@...oo.com.au>,
	Christoph Lameter <clameter@....com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Ingo Molnar <mingo@...e.hu>,
	"Siddha, Suresh B" <suresh.b.siddha@...el.com>
Subject: [PATCH 1/7] Avoid taking rq lock in wake_priority_sleeper

Avoid taking the rq lock in wake_priority sleeper

Avoid taking the request queue lock in wake_priority_sleeper if
there are no running processes.

Signed-off-by: Christoph Lameter <clameter@....com>

Index: linux-2.6.19-rc3/kernel/sched.c
===================================================================
--- linux-2.6.19-rc3.orig/kernel/sched.c	2006-10-26 21:30:11.328325096 -0500
+++ linux-2.6.19-rc3/kernel/sched.c	2006-10-27 11:58:02.142767971 -0500
@@ -2898,6 +2898,9 @@ static inline int wake_priority_sleeper(
 	int ret = 0;
 
 #ifdef CONFIG_SCHED_SMT
+	if (!rq->nr_running)
+		return 0;
+
 	spin_lock(&rq->lock);
 	/*
 	 * If an SMT sibling task has been put to sleep for priority
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/