From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759117Ab3KMOUB (ORCPT ); Wed, 13 Nov 2013 09:20:01 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51416 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754881Ab3KMOUA (ORCPT ); Wed, 13 Nov 2013 09:20:00 -0500 Date: Wed, 13 Nov 2013 09:19:29 -0500 From: Vivek Goyal To: John Stultz Cc: LKML , Peter Zijlstra , Jens Axboe , Fengguang Wu , Ingo Molnar Subject: Re: [PATCH] block: Employ u64_stats_init() Message-ID: <20131113141929.GC7613@redhat.com> References: <1384314134-6895-1-git-send-email-john.stultz@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1384314134-6895-1-git-send-email-john.stultz@linaro.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 12, 2013 at 07:42:14PM -0800, John Stultz wrote: > From: Peter Zijlstra > > Now that seqcounts are lockdep enabled objects, we need to properly > initialize them. > > Without this patch, Fengguang was seeing: > [ 4.127282] INFO: trying to register non-static key. > [ 4.128027] the code is fine but needs lockdep annotation. > [ 4.128027] turning off the locking correctness validator. > [ 4.128027] CPU: 0 PID: 96 Comm: kworker/u4:1 Not tainted 3.12.0-next-20131108-10601-gbad570d #2 > [ 4.128027] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 > [ 4.128027] Workqueue: events_unbound async_run_entry_fn > [ 4.128027] 7908e744 00000000 78019968 79dc7cf2 7a80e0a8 780199a0 7908953e 7a1b7f4d > [ 4.128027] 7a1b7fa7 7a1b7f7d 7f368608 00000000 00000011 44374011 0000a805 7f368110 > [ 4.128027] 7f368110 85bf2a70 00000000 780199cc 7908a1c5 00000000 00000001 00000000 > [ 4.128027] Call Trace: > [ 4.128027] [<7908e744>] ? console_unlock+0x353/0x380 > [ 4.128027] [<79dc7cf2>] dump_stack+0x48/0x60 > [ 4.128027] [<7908953e>] __lock_acquire.isra.26+0x7e3/0xceb > [ 4.128027] [<7908a1c5>] lock_acquire+0x71/0x9a > [ 4.128027] [<794079aa>] ? blk_throtl_bio+0x1c3/0x485 > [ 4.128027] [<7940658b>] throtl_update_dispatch_stats+0x7c/0x153 > [ 4.128027] [<794079aa>] ? blk_throtl_bio+0x1c3/0x485 > [ 4.128027] [<794079aa>] blk_throtl_bio+0x1c3/0x485 > ... > > Cc: Vivek Goyal > Cc: Jens Axboe > Cc: Fengguang Wu > Cc: Ingo Molnar > Reported-by: Fengguang Wu > Signed-off-by: Peter Zijlstra > [jstultz: Folded in another fix from the mailing list as well as a fix > to that fix. Tweaked commit message.] > Signed-off-by: John Stultz Looks good to me. Acked-by: Vivek Goyal Vivek > --- > block/blk-cgroup.h | 10 ++++++++++ > block/blk-throttle.c | 10 ++++++++++ > block/cfq-iosched.c | 25 +++++++++++++++++++++++++ > 3 files changed, 45 insertions(+) > > diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h > index ae6969a..1610b22 100644 > --- a/block/blk-cgroup.h > +++ b/block/blk-cgroup.h > @@ -402,6 +402,11 @@ struct request_list *__blk_queue_next_rl(struct request_list *rl, > #define blk_queue_for_each_rl(rl, q) \ > for ((rl) = &(q)->root_rl; (rl); (rl) = __blk_queue_next_rl((rl), (q))) > > +static inline void blkg_stat_init(struct blkg_stat *stat) > +{ > + u64_stats_init(&stat->syncp); > +} > + > /** > * blkg_stat_add - add a value to a blkg_stat > * @stat: target blkg_stat > @@ -458,6 +463,11 @@ static inline void blkg_stat_merge(struct blkg_stat *to, struct blkg_stat *from) > blkg_stat_add(to, blkg_stat_read(from)); > } > > +static inline void blkg_rwstat_init(struct blkg_rwstat *rwstat) > +{ > + u64_stats_init(&rwstat->syncp); > +} > + > /** > * blkg_rwstat_add - add a value to a blkg_rwstat > * @rwstat: target blkg_rwstat > diff --git a/block/blk-throttle.c b/block/blk-throttle.c > index 8331aba..0653404 100644 > --- a/block/blk-throttle.c > +++ b/block/blk-throttle.c > @@ -256,6 +256,12 @@ static struct throtl_data *sq_to_td(struct throtl_service_queue *sq) > } \ > } while (0) > > +static void tg_stats_init(struct tg_stats_cpu *tg_stats) > +{ > + blkg_rwstat_init(&tg_stats->service_bytes); > + blkg_rwstat_init(&tg_stats->serviced); > +} > + > /* > * Worker for allocating per cpu stat for tgs. This is scheduled on the > * system_wq once there are some groups on the alloc_list waiting for > @@ -269,12 +275,16 @@ static void tg_stats_alloc_fn(struct work_struct *work) > > alloc_stats: > if (!stats_cpu) { > + int cpu; > + > stats_cpu = alloc_percpu(struct tg_stats_cpu); > if (!stats_cpu) { > /* allocation failed, try again after some time */ > schedule_delayed_work(dwork, msecs_to_jiffies(10)); > return; > } > + for_each_possible_cpu(cpu) > + tg_stats_init(per_cpu_ptr(stats_cpu, cpu)); > } > > spin_lock_irq(&tg_stats_alloc_lock); > diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c > index 434944c..4d5cec1 100644 > --- a/block/cfq-iosched.c > +++ b/block/cfq-iosched.c > @@ -1508,6 +1508,29 @@ static void cfq_init_cfqg_base(struct cfq_group *cfqg) > } > > #ifdef CONFIG_CFQ_GROUP_IOSCHED > +static void cfqg_stats_init(struct cfqg_stats *stats) > +{ > + blkg_rwstat_init(&stats->service_bytes); > + blkg_rwstat_init(&stats->serviced); > + blkg_rwstat_init(&stats->merged); > + blkg_rwstat_init(&stats->service_time); > + blkg_rwstat_init(&stats->wait_time); > + blkg_rwstat_init(&stats->queued); > + > + blkg_stat_init(&stats->sectors); > + blkg_stat_init(&stats->time); > + > +#ifdef CONFIG_DEBUG_BLK_CGROUP > + blkg_stat_init(&stats->unaccounted_time); > + blkg_stat_init(&stats->avg_queue_size_sum); > + blkg_stat_init(&stats->avg_queue_size_samples); > + blkg_stat_init(&stats->dequeue); > + blkg_stat_init(&stats->group_wait_time); > + blkg_stat_init(&stats->idle_time); > + blkg_stat_init(&stats->empty_time); > +#endif > +} > + > static void cfq_pd_init(struct blkcg_gq *blkg) > { > struct cfq_group *cfqg = blkg_to_cfqg(blkg); > @@ -1515,6 +1538,8 @@ static void cfq_pd_init(struct blkcg_gq *blkg) > cfq_init_cfqg_base(cfqg); > cfqg->weight = blkg->blkcg->cfq_weight; > cfqg->leaf_weight = blkg->blkcg->cfq_leaf_weight; > + cfqg_stats_init(&cfqg->stats); > + cfqg_stats_init(&cfqg->dead_stats); > } > > static void cfq_pd_offline(struct blkcg_gq *blkg) > -- > 1.8.3.2