Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752682Ab0GAIOW (ORCPT ); Thu, 1 Jul 2010 04:14:22 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:61728 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751680Ab0GAIOT (ORCPT ); Thu, 1 Jul 2010 04:14:19 -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=YhtepkdDQyca7mFLe9Pun5tgvTWntrWPkqu6yc4XLDc35g9kUoqhKbIJ0tHeJDDFJh kTI+KoYsiy4hI/UNiFXtd6yJiqIY/ZCYinU4Z4tzJgGlN+vnIbXuCo297ESR2r+wokpV H+yBIShI4aK6u/EOWxLfrjN7bqmzgzmz1u40k= Date: Thu, 1 Jul 2010 11:18:25 +0300 From: Sergey Senozhatsky To: Peter Zijlstra Cc: Andrew Morton , Sergey Senozhatsky , Arjan van de Ven , "Rafael J. Wysocki" , Maxim Levitsky , Len Brown , Pavel Machek , Jiri Slaby , linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Thomas Gleixner , Ingo Molnar Subject: Re: [PATCH] sched: Cure nr_iowait_cpu() users Message-ID: <20100701081825.GA3982@swordfish.minsk.epam.com> References: <20100614151735.GB3448@swordfish.minsk.epam.com> <20100614204021.52c50cdc@infradead.org> <20100615061927.GA3312@swordfish> <20100615072435.5a47d850@infradead.org> <20100615145029.GB3967@swordfish.minsk.epam.com> <20100615080808.6286448b@infradead.org> <20100617062950.GA3979@swordfish> <1277476773.32034.639.camel@twins> <20100630125853.245e6b99.akpm@linux-foundation.org> <1277968037.1868.120.camel@laptop> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/9DWx/yDrRhgMJTb" Content-Disposition: inline In-Reply-To: <1277968037.1868.120.camel@laptop> 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: 5801 Lines: 183 --/9DWx/yDrRhgMJTb Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Acked-by: Sergey Senozhatsky (??) Sergey On (07/01/10 09:07), Peter Zijlstra wrote: > Subject: [PATCH] sched: Cure nr_iowait_cpu() users > X-Mailer: Evolution 2.28.3=20 >=20 > With 0224cf4c5e (sched: Intoduce get_cpu_iowait_time_us()) Arjan broke > things by not making sure preemption was indeed disabled by the callers > of nr_iowait_cpu() which took the iowait value of the current cpu. >=20 > This resulted in a heap of preempt warnings. Cure this by making > nr_iowait_cpu() take a cpu number and fix up the callers to pass in the > right number. >=20 > Signed-off-by: Peter Zijlstra > --- > Confirmed to work.. >=20 > drivers/cpuidle/governors/menu.c | 4 ++-- > include/linux/sched.h | 2 +- > kernel/sched.c | 4 ++-- > kernel/time/tick-sched.c | 16 ++++++++-------- > 4 files changed, 13 insertions(+), 13 deletions(-) >=20 > diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors= /menu.c > index 52ff8aa..1b12870 100644 > --- a/drivers/cpuidle/governors/menu.c > +++ b/drivers/cpuidle/governors/menu.c > @@ -143,7 +143,7 @@ static inline int which_bucket(unsigned int duration) > * This allows us to calculate > * E(duration)|iowait > */ > - if (nr_iowait_cpu()) > + if (nr_iowait_cpu(smp_processor_id())) > bucket =3D BUCKETS/2; > =20 > if (duration < 10) > @@ -175,7 +175,7 @@ static inline int performance_multiplier(void) > mult +=3D 2 * get_loadavg(); > =20 > /* for IO wait tasks (per cpu!) we add 5x each */ > - mult +=3D 10 * nr_iowait_cpu(); > + mult +=3D 10 * nr_iowait_cpu(smp_processor_id()); > =20 > return mult; > } > diff --git a/include/linux/sched.h b/include/linux/sched.h > index a61c08c..1f25798 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); > =20 > =20 > diff --git a/kernel/sched.c b/kernel/sched.c > index 71e3dc8..d3c0262 100644 > --- a/kernel/sched.c > +++ b/kernel/sched.c > @@ -2946,9 +2946,9 @@ unsigned long nr_iowait(void) > return sum; > } > =20 > -unsigned long nr_iowait_cpu(void) > +unsigned long nr_iowait_cpu(int cpu) > { > - struct rq *this =3D this_rq(); > + struct rq *this =3D cpu_rq(cpu); > return atomic_read(&this->nr_iowait); > } > =20 > diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c > index e0707ea..17525ca 100644 > --- a/kernel/time/tick-sched.c > +++ b/kernel/time/tick-sched.c > @@ -154,14 +154,14 @@ static void tick_nohz_update_jiffies(ktime_t now) > * Updates the per cpu time idle statistics counters > */ > static void > -update_ts_time_stats(struct tick_sched *ts, ktime_t now, u64 *last_updat= e_time) > +update_ts_time_stats(int cpu, struct tick_sched *ts, ktime_t now, u64 *l= ast_update_time) > { > ktime_t delta; > =20 > if (ts->idle_active) { > delta =3D ktime_sub(now, ts->idle_entrytime); > ts->idle_sleeptime =3D ktime_add(ts->idle_sleeptime, delta); > - if (nr_iowait_cpu() > 0) > + if (nr_iowait_cpu(cpu) > 0) > ts->iowait_sleeptime =3D ktime_add(ts->iowait_sleeptime, delta); > ts->idle_entrytime =3D now; > } > @@ -175,19 +175,19 @@ static void tick_nohz_stop_idle(int cpu, ktime_t no= w) > { > struct tick_sched *ts =3D &per_cpu(tick_cpu_sched, cpu); > =20 > - update_ts_time_stats(ts, now, NULL); > + update_ts_time_stats(cpu, ts, now, NULL); > ts->idle_active =3D 0; > =20 > sched_clock_idle_wakeup_event(0); > } > =20 > -static ktime_t tick_nohz_start_idle(struct tick_sched *ts) > +static ktime_t tick_nohz_start_idle(int cpu, struct tick_sched *ts) > { > ktime_t now; > =20 > now =3D ktime_get(); > =20 > - update_ts_time_stats(ts, now, NULL); > + update_ts_time_stats(cpu, ts, now, NULL); > =20 > ts->idle_entrytime =3D now; > ts->idle_active =3D 1; > @@ -216,7 +216,7 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_ti= me) > if (!tick_nohz_enabled) > return -1; > =20 > - update_ts_time_stats(ts, ktime_get(), last_update_time); > + update_ts_time_stats(cpu, ts, ktime_get(), last_update_time); > =20 > return ktime_to_us(ts->idle_sleeptime); > } > @@ -242,7 +242,7 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_= time) > if (!tick_nohz_enabled) > return -1; > =20 > - update_ts_time_stats(ts, ktime_get(), last_update_time); > + update_ts_time_stats(cpu, ts, ktime_get(), last_update_time); > =20 > return ktime_to_us(ts->iowait_sleeptime); > } > @@ -284,7 +284,7 @@ void tick_nohz_stop_sched_tick(int inidle) > */ > ts->inidle =3D 1; > =20 > - now =3D tick_nohz_start_idle(ts); > + now =3D tick_nohz_start_idle(cpu, ts); > =20 > /* > * If this cpu is offline and it is the one which updates >=20 --/9DWx/yDrRhgMJTb Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iJwEAQECAAYFAkwsT1EACgkQfKHnntdSXjSLcgQA21C6/L2c7WCeZTAckLMwmKc0 AFy18Er4rqfSKTUy46S6dp7PA7NncmvsEcSGkfN5htkaiXe6EGQUsVqzHZb779GD uavBk9LdAGZRFFXFjTaqWToXwd5E73JMgHNqPBqh+L/xmen/DnEakzd7ngZD6fY2 fX+UxnTvnulOaKTIN7s= =bj1R -----END PGP SIGNATURE----- --/9DWx/yDrRhgMJTb-- -- 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/