Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755531Ab0FNPOI (ORCPT ); Mon, 14 Jun 2010 11:14:08 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:48266 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754593Ab0FNPOG (ORCPT ); Mon, 14 Jun 2010 11:14:06 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=RvQCrLTuy3KIgg9+MR0JZ5ls1xRUi4AGxqTk/nbKDv7YXeGeUHaytEFykUzwJOq7io c9WtU4eGuiT97f03/AewvE/oU9PskzbR6HgATfifW0ZcVPxUUxEsFZx9+U/CgD7W+vgw CNI8ew54k8Z011ODFYJiB3gaR3Z4bNMhVNb+Y= Date: Mon, 14 Jun 2010 18:17:35 +0300 From: Sergey Senozhatsky To: Arjan van de Ven Cc: Sergey Senozhatsky , "Rafael J. Wysocki" , Maxim Levitsky , Len Brown , Pavel Machek , Jiri Slaby , Andrew Morton , linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: BUG: using smp_processor_id() in preemptible code: s2disk Message-ID: <20100614151735.GB3448@swordfish.minsk.epam.com> References: <20100613203352.GA3577@swordfish> <1276461183.2659.4.camel@maxim-laptop> <201006140136.18652.rjw@sisk.pl> <20100614140941.GA3581@swordfish.minsk.epam.com> <20100614073853.6fa2f91f@infradead.org> <20100614145439.GA3448@swordfish.minsk.epam.com> <20100614080154.7d6a71fc@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100614080154.7d6a71fc@infradead.org> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2874 Lines: 108 On (06/14/10 08:01), Arjan van de Ven wrote: > > decided to patch nr_iowait_cpu instead. > > the bug is that it needs to be > > nr_iowait_cpu(int cpu) > Something similar to this? --- diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 52ff8aa..4871ed5 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -137,14 +137,17 @@ static inline int which_bucket(unsigned int duration) { int bucket = 0; + int cpu = get_cpu(); /* * We keep two groups of stats; one with no * IO pending, one without. * This allows us to calculate * E(duration)|iowait */ - if (nr_iowait_cpu()) + if (nr_iowait_cpu(cpu)) bucket = BUCKETS/2; + + put_cpu(); if (duration < 10) return bucket; @@ -169,14 +172,17 @@ static inline int which_bucket(unsigned int duration) static inline int performance_multiplier(void) { int mult = 1; - + int cpu = get_cpu(); + /* for higher loadavg, we are more reluctant */ mult += 2 * get_loadavg(); /* for IO wait tasks (per cpu!) we add 5x each */ - mult += 10 * nr_iowait_cpu(); + mult += 10 * nr_iowait_cpu(cpu); + put_cpu(); + return mult; } diff --git a/include/linux/sched.h b/include/linux/sched.h index f118809..747fcae 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -139,7 +139,7 @@ extern int nr_processes(void); extern unsigned long nr_running(void); extern unsigned long nr_uninterruptible(void); extern unsigned long nr_iowait(void); -extern unsigned long nr_iowait_cpu(void); +extern unsigned long nr_iowait_cpu(int cpu); extern unsigned long this_cpu_load(void); diff --git a/kernel/sched.c b/kernel/sched.c index f8b8996..f61b48e 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2864,9 +2864,9 @@ unsigned long nr_iowait(void) return sum; } -unsigned long nr_iowait_cpu(void) +unsigned long nr_iowait_cpu(int cpu) { - struct rq *this = this_rq(); + struct rq *this = cpu_rq(cpu); return atomic_read(&this->nr_iowait); } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 1d7b9bc..101e8aa 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -159,10 +159,12 @@ update_ts_time_stats(struct tick_sched *ts, ktime_t now, u64 *last_update_time) ktime_t delta; if (ts->idle_active) { + int cpu = get_cpu(); delta = ktime_sub(now, ts->idle_entrytime); ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); - if (nr_iowait_cpu() > 0) + if (nr_iowait_cpu(cpu) > 0) ts->iowait_sleeptime = ktime_add(ts->iowait_sleeptime, delta); + put_cpu(); ts->idle_entrytime = now; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/