Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755602AbZKEDKX (ORCPT ); Wed, 4 Nov 2009 22:10:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751499AbZKEDKW (ORCPT ); Wed, 4 Nov 2009 22:10:22 -0500 Received: from smtp-out.google.com ([216.239.45.13]:6626 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750890AbZKEDKV convert rfc822-to-8bit (ORCPT ); Wed, 4 Nov 2009 22:10:21 -0500 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=mime-version:in-reply-to:references:from:date:message-id: subject:to:cc:content-type:content-transfer-encoding:x-system-of-record; b=fgEYHUwrKYsrJzcZL8wO0gZkv6uCf/DfwyInAT2k0OjSByjiEPBBO+FguZ3Oofw22 q8snm89+9i8xlL7OzXIRA== MIME-Version: 1.0 In-Reply-To: <1257291837-6246-12-git-send-email-vgoyal@redhat.com> References: <1257291837-6246-1-git-send-email-vgoyal@redhat.com> <1257291837-6246-12-git-send-email-vgoyal@redhat.com> From: Divyesh Shah Date: Wed, 4 Nov 2009 19:10:00 -0800 Message-ID: Subject: Re: [PATCH 11/20] blkio: Some CFQ debugging Aid To: Vivek Goyal Cc: linux-kernel@vger.kernel.org, jens.axboe@oracle.com, nauman@google.com, lizf@cn.fujitsu.com, ryov@valinux.co.jp, fernando@oss.ntt.co.jp, s-uchida@ap.jp.nec.com, taka@valinux.co.jp, guijianfeng@cn.fujitsu.com, jmoyer@redhat.com, balbir@linux.vnet.ibm.com, righi.andrea@gmail.com, m-ikeda@ds.jp.nec.com, akpm@linux-foundation.org, riel@redhat.com, kamezawa.hiroyu@jp.fujitsu.com Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7649 Lines: 196 In the previous patchset when merged with the bio tracking patches we had a very convenient biocg_id we could use for debugging. If the eventual plan is to merge the biotrack patches, do you think it makes sense to introduce the per-blkio cgroup id here when DEBUG_BLK_CGROUP=y and use that for all traces? The cgroup path name seems ugly to me. -Divyesh On Tue, Nov 3, 2009 at 3:43 PM, Vivek Goyal wrote: > o Some CFQ debugging Aid. > > Signed-off-by: Vivek Goyal > --- > ?block/Kconfig ? ? ? ? | ? ?9 +++++++++ > ?block/Kconfig.iosched | ? ?9 +++++++++ > ?block/blk-cgroup.c ? ?| ? ?4 ++++ > ?block/blk-cgroup.h ? ?| ? 13 +++++++++++++ > ?block/cfq-iosched.c ? | ? 33 +++++++++++++++++++++++++++++++++ > ?5 files changed, 68 insertions(+), 0 deletions(-) > > diff --git a/block/Kconfig b/block/Kconfig > index 6ba1a8e..e20fbde 100644 > --- a/block/Kconfig > +++ b/block/Kconfig > @@ -90,6 +90,15 @@ config BLK_CGROUP > ? ? ? ?control disk bandwidth allocation (proportional time slice allocation) > ? ? ? ?to such task groups. > > +config DEBUG_BLK_CGROUP > + ? ? ? bool > + ? ? ? depends on BLK_CGROUP > + ? ? ? default n > + ? ? ? ---help--- > + ? ? ? Enable some debugging help. Currently it stores the cgroup path > + ? ? ? in the blk group which can be used by cfq for tracing various > + ? ? ? group related activity. > + > ?endif # BLOCK > > ?config BLOCK_COMPAT > diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched > index a521c69..9c5f0b5 100644 > --- a/block/Kconfig.iosched > +++ b/block/Kconfig.iosched > @@ -48,6 +48,15 @@ config CFQ_GROUP_IOSCHED > ? ? ? ?---help--- > ? ? ? ? ?Enable group IO scheduling in CFQ. > > +config DEBUG_CFQ_IOSCHED > + ? ? ? bool "Debug CFQ Scheduling" > + ? ? ? depends on CFQ_GROUP_IOSCHED > + ? ? ? select DEBUG_BLK_CGROUP > + ? ? ? default n > + ? ? ? ---help--- > + ? ? ? ? Enable CFQ IO scheduling debugging in CFQ. Currently it makes > + ? ? ? ? blktrace output more verbose. > + > ?choice > ? ? ? ?prompt "Default I/O scheduler" > ? ? ? ?default DEFAULT_CFQ > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index a62b8a3..4c68682 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -39,6 +39,10 @@ void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, > ? ? ? ?blkg->blkcg_id = css_id(&blkcg->css); > ? ? ? ?hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list); > ? ? ? ?spin_unlock_irqrestore(&blkcg->lock, flags); > +#ifdef CONFIG_DEBUG_BLK_CGROUP > + ? ? ? /* Need to take css reference ? */ > + ? ? ? cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path)); > +#endif > ?} > > ?static void __blkiocg_del_blkio_group(struct blkio_group *blkg) > diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h > index 2bf736b..cb72c35 100644 > --- a/block/blk-cgroup.h > +++ b/block/blk-cgroup.h > @@ -26,12 +26,25 @@ struct blkio_group { > ? ? ? ?void *key; > ? ? ? ?struct hlist_node blkcg_node; > ? ? ? ?unsigned short blkcg_id; > +#ifdef CONFIG_DEBUG_BLK_CGROUP > + ? ? ? /* Store cgroup path */ > + ? ? ? char path[128]; > +#endif > ?}; > > ?#define BLKIO_WEIGHT_MIN ? ? ? 100 > ?#define BLKIO_WEIGHT_MAX ? ? ? 1000 > ?#define BLKIO_WEIGHT_DEFAULT ? 500 > > +#ifdef CONFIG_DEBUG_BLK_CGROUP > +static inline char *blkg_path(struct blkio_group *blkg) > +{ > + ? ? ? return blkg->path; > +} > +#else > +static inline char *blkg_path(struct blkio_group *blkg) { return NULL; } > +#endif > + > ?extern struct blkio_cgroup blkio_root_cgroup; > ?struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup); > ?void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, > diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c > index b9a052b..2fde3c4 100644 > --- a/block/cfq-iosched.c > +++ b/block/cfq-iosched.c > @@ -258,8 +258,29 @@ CFQ_CFQQ_FNS(sync); > ?CFQ_CFQQ_FNS(coop); > ?#undef CFQ_CFQQ_FNS > > +#ifdef CONFIG_DEBUG_CFQ_IOSCHED > +#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \ > + ? ? ? blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \ > + ? ? ? ? ? ? ? ? ? ? ? cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ > + ? ? ? ? ? ? ? ? ? ? ? blkg_path(&cfqq_to_cfqg((cfqq))->blkg), ##args); > + > +#define cfq_log_cfqe(cfqd, cfqe, fmt, args...) ? ? ? ? ? ? ? ? \ > + ? ? ? if (cfqq_of(cfqe)) { ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\ > + ? ? ? ? ? ? ? struct cfq_queue *cfqq = cfqq_of(cfqe); ? ? ? ? ? ? ? ? \ > + ? ? ? ? ? ? ? blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, ? ? \ > + ? ? ? ? ? ? ? ? ? ? ? (cfqq)->pid, cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ > + ? ? ? ? ? ? ? ? ? ? ? blkg_path(&cfqq_to_cfqg((cfqq))->blkg), ##args);\ > + ? ? ? } else { ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\ > + ? ? ? ? ? ? ? struct cfq_group *cfqg = cfqg_of(cfqe); ? ? ? ? ? ? ? ? \ > + ? ? ? ? ? ? ? blk_add_trace_msg((cfqd)->queue, "%s " fmt, ? ? ? ? ? ? \ > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? blkg_path(&(cfqg)->blkg), ##args); ? ? ?\ > + ? ? ? } > +#else > ?#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \ > ? ? ? ?blk_add_trace_msg((cfqd)->queue, "cfq%d " fmt, (cfqq)->pid, ##args) > +#define cfq_log_cfqe(cfqd, cfqe, fmt, args...) > +#endif > + > ?#define cfq_log(cfqd, fmt, args...) ? ?\ > ? ? ? ?blk_add_trace_msg((cfqd)->queue, "cfq " fmt, ##args) > > @@ -400,6 +421,8 @@ cfq_init_cfqe_parent(struct cfq_entity *cfqe, struct cfq_entity *p_cfqe) > ?#define for_each_entity(entity) ? ? ? ?\ > ? ? ? ?for (; entity && entity->parent; entity = entity->parent) > > +#define cfqe_is_cfqq(cfqe) ? ? (!(cfqe)->my_sd) > + > ?static inline struct cfq_group *cfqg_of_blkg(struct blkio_group *blkg) > ?{ > ? ? ? ?if (blkg) > @@ -588,6 +611,8 @@ void cfq_delink_blkio_group(void *key, struct blkio_group *blkg) > ?#define for_each_entity(entity) ? ? ? ?\ > ? ? ? ?for (; entity != NULL; entity = NULL) > > +#define cfqe_is_cfqq(cfqe) ? ? 1 > + > ?static void cfq_release_cfq_groups(struct cfq_data *cfqd) {} > ?static inline void cfq_get_cfqg_ref(struct cfq_group *cfqg) {} > ?static inline void cfq_put_cfqg(struct cfq_group *cfqg) {} > @@ -885,6 +910,10 @@ static void dequeue_cfqq(struct cfq_queue *cfqq) > ? ? ? ? ? ? ? ?struct cfq_sched_data *sd = cfq_entity_sched_data(cfqe); > > ? ? ? ? ? ? ? ?dequeue_cfqe(cfqe); > + ? ? ? ? ? ? ? if (!cfqe_is_cfqq(cfqe)) { > + ? ? ? ? ? ? ? ? ? ? ? cfq_log_cfqe(cfqq->cfqd, cfqe, "del_from_rr group"); > + ? ? ? ? ? ? ? } > + > ? ? ? ? ? ? ? ?/* Do not dequeue parent if it has other entities under it */ > ? ? ? ? ? ? ? ?if (sd->nr_active) > ? ? ? ? ? ? ? ? ? ? ? ?break; > @@ -970,6 +999,8 @@ static void requeue_cfqq(struct cfq_queue *cfqq, int add_front) > > ?static void cfqe_served(struct cfq_entity *cfqe, unsigned long served) > ?{ > + ? ? ? struct cfq_data *cfqd = cfqq_of(cfqe)->cfqd; > + > ? ? ? ?for_each_entity(cfqe) { > ? ? ? ? ? ? ? ?/* > ? ? ? ? ? ? ? ? * Can't update entity disk time while it is on sorted rb-tree > @@ -979,6 +1010,8 @@ static void cfqe_served(struct cfq_entity *cfqe, unsigned long served) > ? ? ? ? ? ? ? ?cfqe->vdisktime += cfq_delta_fair(served, cfqe); > ? ? ? ? ? ? ? ?update_min_vdisktime(cfqe->st); > ? ? ? ? ? ? ? ?__enqueue_cfqe(cfqe->st, cfqe, 0); > + ? ? ? ? ? ? ? cfq_log_cfqe(cfqd, cfqe, "served: vt=%llx min_vt=%llx", > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? cfqe->vdisktime, cfqe->st->min_vdisktime); > > ? ? ? ? ? ? ? ?/* If entity prio class has changed, take that into account */ > ? ? ? ? ? ? ? ?if (unlikely(cfqe->ioprio_class_changed)) { > -- > 1.6.2.5 > > -- 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/