linux-kernel - [tip:sched/core] sched/nohz: Correctly initialize 'next

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] [day] [month] [year] [list]

Date:	Mon, 12 Mar 2012 21:45:55 -0700
From:	tip-bot for Diwakar Tundlam <dtundlam@...dia.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, hpa@...or.com, mingo@...hat.com,
	a.p.zijlstra@...llo.nl, dtundlam@...dia.com, tglx@...utronix.de,
	mingo@...e.hu
Subject: [tip:sched/core] sched/nohz: Correctly initialize 'next_balance'
  in 'nohz' idle balancer

Commit-ID:  554cecaf733623b327eef9652b65965eb1081b81
Gitweb:     http://git.kernel.org/tip/554cecaf733623b327eef9652b65965eb1081b81
Author:     Diwakar Tundlam <dtundlam@...dia.com>
AuthorDate: Wed, 7 Mar 2012 14:44:26 -0800
Committer:  Ingo Molnar <mingo@...e.hu>
CommitDate: Mon, 12 Mar 2012 20:43:16 +0100

sched/nohz: Correctly initialize 'next_balance' in 'nohz' idle balancer

The 'next_balance' field of 'nohz' idle balancer must be initialized
to jiffies. Since jiffies is initialized to negative 300 seconds the
'nohz' idle balancer does not run for the first 300s (5mins) after
bootup. If no new processes are spawed or no idle cycles happen, the
load on the cpus will remain unbalanced for that duration.

Signed-off-by: Diwakar Tundlam <dtundlam@...dia.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@...llo.nl>
Link: http://lkml.kernel.org/r/1DD7BFEDD3147247B1355BEFEFE4665237994F30EF@HQMAIL04.nvidia.com
Signed-off-by: Ingo Molnar <mingo@...e.hu>
---
 kernel/sched/fair.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index def17aa..11f3979 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5571,6 +5571,7 @@ __init void init_sched_fair_class(void)
 	open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
 
 #ifdef CONFIG_NO_HZ
+	nohz.next_balance = jiffies;
 	zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
 	cpu_notifier(sched_ilb_notifier, 0);
 #endif
--
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/