Return-path: Received: from mail-ww0-f46.google.com ([74.125.82.46]:57685 "EHLO mail-ww0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932525Ab0FPVAk convert rfc822-to-8bit (ORCPT ); Wed, 16 Jun 2010 17:00:40 -0400 MIME-Version: 1.0 Reply-To: sedat.dilek@gmail.com In-Reply-To: <20100616134231.23ff30da.akpm@linux-foundation.org> References:

<201006091122.35304.rjw@sisk.pl> <20100616134231.23ff30da.akpm@linux-foundation.org> Date: Wed, 16 Jun 2010 23:00:37 +0200 Message-ID: Subject: Re: 2.6.35-rc2-git2: Reported regressions from 2.6.34 From: Sedat Dilek To: Andrew Morton Cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Maciej Rutecki , Linus Torvalds , Kernel Testers List , Network Development , Linux ACPI , Linux PM List , Linux SCSI List , Linux Wireless List , DRI , dmonakhov@openvz.org Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: How do cpu-freq related stuff find its way into mainline? Is there a GIT repository/branch on where you can pull from? - Sedat - On Wed, Jun 16, 2010 at 10:42 PM, Andrew Morton wrote: > On Wed, 9 Jun 2010 11:22:35 +0200 > "Rafael J. Wysocki" wrote: > >> On Wednesday 09 June 2010, Sedat Dilek wrote: >> > The patch from [1] is still missing. >> > >> > "cpufreq-call-nr_iowait_cpu-with-disabled-preemption.patch" from >> > Dmitry Monakhoc >> > >> > Tested-by: Sedat Dilek >> > Tested-by Maciej Rutecki >> > >> > I have already reported this issue on LKML [2] and cpufreq ML [3]. >> > >> > - Sedat - >> > >> > [1] http://www.spinics.net/lists/cpufreq/msg01631.html >> > [2] http://lkml.org/lkml/2010/5/31/77 >> > [3] http://www.spinics.net/lists/cpufreq/msg01637.html >> >> Thanks, added. > > I just merged a different patch whcih should address this: > > > From: Sergey Senozhatsky > > Fix > > BUG: using smp_processor_id() in preemptible [00000000] code: s2disk/3392 > caller is nr_iowait_cpu+0xe/0x1e > Pid: 3392, comm: s2disk Not tainted 2.6.35-rc3-dbg-00106-ga75e02b #2 > Call Trace: > [] debug_smp_processor_id+0xa5/0xbc > [] nr_iowait_cpu+0xe/0x1e > [] update_ts_time_stats+0x32/0x6c > [] get_cpu_idle_time_us+0x36/0x58 > [] get_cpu_idle_time+0x12/0x74 > [] cpufreq_governor_dbs+0xc3/0x2dc > [] __cpufreq_governor+0x51/0x85 > [] __cpufreq_set_policy+0x10c/0x13d > [] cpufreq_add_dev_interface+0x212/0x233 > [] ? handle_update+0x0/0xd > [] cpufreq_add_dev+0x34b/0x35a > [] ? schedule_delayed_work_on+0x11/0x13 > [] cpufreq_cpu_callback+0x59/0x63 > [] notifier_call_chain+0x26/0x48 > [] __raw_notifier_call_chain+0xe/0x10 > [] __cpu_notify+0x15/0x29 > [] cpu_notify+0xd/0xf > [] _cpu_up+0xaf/0xd2 > [] enable_nonboot_cpus+0x3d/0x94 > [] hibernation_snapshot+0x104/0x1a2 > [] snapshot_ioctl+0x24b/0x53e > [] ? sub_preempt_count+0x7c/0x89 > [] vfs_ioctl+0x2e/0x8c > [] ? snapshot_ioctl+0x0/0x53e > [] do_vfs_ioctl+0x42f/0x45a > [] ? fsnotify_modify+0x4f/0x5a > [] ? tty_write+0x0/0x1d0 > [] ? vfs_write+0xa2/0xda > [] sys_ioctl+0x41/0x62 > [] sysenter_do_call+0x12/0x2d > > The initial fix was to use get_cpu/put_cpu in nr_iowait_cpu. However, > Arjan stated that "the bug is that it needs to be nr_iowait_cpu(int cpu)". > > This patch introduces nr_iowait_cpu(int cpu) and changes to it callers. > > akpm: addresses about 30,000,000 different bug reports. > > Signed-off-by: Sergey Senozhatsky > Cc: Arjan van de Ven > Cc: "Rafael J. Wysocki" > Cc: Maxim Levitsky > Cc: Len Brown > Cc: Pavel Machek > Cc: Jiri Slaby > Signed-off-by: Andrew Morton > --- > > drivers/cpuidle/governors/menu.c | 10 ++++++++-- > include/linux/sched.h | 2 +- > kernel/sched.c | 4 ++-- > kernel/time/tick-sched.c | 4 +++- > 4 files changed, 14 insertions(+), 6 deletions(-) > > diff -puN drivers/cpuidle/governors/menu.c~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu drivers/cpuidle/governors/menu.c > --- a/drivers/cpuidle/governors/menu.c~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu > +++ a/drivers/cpuidle/governors/menu.c > @@ -137,15 +137,18 @@ static inline int which_bucket(unsigned > { > 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; > if (duration < 100) > @@ -169,13 +172,16 @@ static inline int which_bucket(unsigned > 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 -puN include/linux/sched.h~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu include/linux/sched.h > --- a/include/linux/sched.h~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu > +++ a/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 -puN kernel/sched.c~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu kernel/sched.c > --- a/kernel/sched.c~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu > +++ a/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 -puN kernel/time/tick-sched.c~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu kernel/time/tick-sched.c > --- a/kernel/time/tick-sched.c~cpuidle-avoid-using-smp_processor_id-in-preemptible-code-nr_iowait_cpu > +++ a/kernel/time/tick-sched.c > @@ -159,10 +159,12 @@ update_ts_time_stats(struct tick_sched * > 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; > } > > _ > >