From: Diwakar Tundlam Date: Wed, 7 Mar 2012 22:44:26 +0000 (-0800) Subject: sched/nohz: Correctly initialize 'next_balance' in 'nohz' idle balancer X-Git-Tag: v3.4-rc1~3^2~15 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=554cecaf733623b327eef9652b65965eb1081b81;p=platform%2Fupstream%2Fkernel-adaptation-pc.git 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 Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1DD7BFEDD3147247B1355BEFEFE4665237994F30EF@HQMAIL04.nvidia.com Signed-off-by: Ingo Molnar --- 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