From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gui Jianfeng Subject: Re: [PATCH 18/19] io-controller: Debug hierarchical IO scheduling Date: Fri, 19 Jun 2009 14:26:06 +0800 Message-ID: <4A3B2F7E.10405@cn.fujitsu.com> References: <1244513342-11758-1-git-send-email-vgoyal@redhat.com> <1244513342-11758-19-git-send-email-vgoyal@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1244513342-11758-19-git-send-email-vgoyal@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Vivek Goyal Cc: dhaval@linux.vnet.ibm.com, snitzer@redhat.com, peterz@infradead.org, dm-devel@redhat.com, dpshah@google.com, jens.axboe@oracle.com, agk@redhat.com, balbir@linux.vnet.ibm.com, paolo.valente@unimore.it, fernando@oss.ntt.co.jp, mikew@google.com, jmoyer@redhat.com, nauman@google.com, m-ikeda@ds.jp.nec.com, lizf@cn.fujitsu.com, fchecconi@gmail.com, akpm@linux-foundation.org, jbaron@redhat.com, linux-kernel@vger.kernel.org, s-uchida@ap.jp.nec.com, righi.andrea@gmail.com, containers@lists.linux-foundation.org List-Id: dm-devel.ids Vivek Goyal wrote: ... > +static inline void bfq_account_for_entity_addition(struct io_entity *entity) > +{ > + struct io_group *iog = io_entity_to_iog(entity); > + > + if (iog) { > + struct elv_fq_data *efqd; > + char path[128]; > + > + /* > + * Keep track of how many times a group has been removed > + * from active tree because it did not have any active > + * backlogged ioq under it > + */ > + iog->queue++; > + iog->queue_start = jiffies; > + > + /* Log group addition event */ > + rcu_read_lock(); > + efqd = rcu_dereference(iog->key); > + if (efqd) { > + io_group_path(iog, path, sizeof(path)); > + elv_log(efqd, "add group=%s weight=%ld", path, > + iog->entity.weight); Since cgroup path is already cached, why not use it. :) Signed-off-by: Gui Jianfeng --- block/elevator-fq.c | 12 ++++-------- 1 files changed, 4 insertions(+), 8 deletions(-) diff --git a/block/elevator-fq.c b/block/elevator-fq.c index bfa79c9..1a397c3 100644 --- a/block/elevator-fq.c +++ b/block/elevator-fq.c @@ -183,7 +183,6 @@ static inline void bfq_account_for_entity_addition(struct io_entity *entity) if (iog) { struct elv_fq_data *efqd; - char path[128]; /* * Keep track of how many times a group has been removed @@ -197,9 +196,8 @@ static inline void bfq_account_for_entity_addition(struct io_entity *entity) rcu_read_lock(); efqd = rcu_dereference(iog->key); if (efqd) { - io_group_path(iog, path, sizeof(path)); - elv_log(efqd, "add group=%s weight=%ld", path, - iog->entity.weight); + elv_log(efqd, "add group=%s weight=%ld", iog->path, + iog->entity.weight); } rcu_read_unlock(); } @@ -215,7 +213,6 @@ static inline void bfq_account_for_entity_deletion(struct io_entity *entity) if (iog) { struct elv_fq_data *efqd; - char path[128]; iog->dequeue++; /* Keep a track of how long group was on active tree */ @@ -227,9 +224,8 @@ static inline void bfq_account_for_entity_deletion(struct io_entity *entity) rcu_read_lock(); efqd = rcu_dereference(iog->key); if (efqd) { - io_group_path(iog, path, sizeof(path)); - elv_log(efqd, "del group=%s weight=%ld", path, - iog->entity.weight); + elv_log(efqd, "del group=%s weight=%ld", iog->path, + iog->entity.weight); } rcu_read_unlock(); } -- 1.5.4.rc3