Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751481Ab0BZF15 (ORCPT ); Fri, 26 Feb 2010 00:27:57 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:59529 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751073Ab0BZF1z (ORCPT ); Fri, 26 Feb 2010 00:27:55 -0500 Message-ID: <4B875A73.2070103@cn.fujitsu.com> Date: Fri, 26 Feb 2010 13:21:55 +0800 From: Gui Jianfeng User-Agent: Thunderbird 2.0.0.23 (Windows/20090812) MIME-Version: 1.0 To: Jens Axboe CC: Vivek Goyal , Corrado Zoccolo , linux kernel mailing list , Li Zefan Subject: Re: [PATCH] cfq: Remove useless css reference get References: <4B289C93.3070603@cn.fujitsu.com> <20091221162850.GB10994@redhat.com> In-Reply-To: <20091221162850.GB10994@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3047 Lines: 99 Vivek Goyal wrote: > On Wed, Dec 16, 2009 at 04:38:43PM +0800, Gui Jianfeng wrote: >> There's no need to take css reference here, for the caller >> has already called rcu_read_lock() to prevent cgroup from >> being removed. >> >> Signed-off-by: Gui Jianfeng >> Reviewed-by: Li Zefan > > Acked-by: Vivek Goyal Hi Jens Would you pick this patch up? > > Thanks > Vivek > >> --- >> block/blk-cgroup.c | 14 -------------- >> block/blk-cgroup.h | 3 --- >> block/cfq-iosched.c | 5 ----- >> 3 files changed, 0 insertions(+), 22 deletions(-) >> >> diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c >> index 1fa2654..cba28f4 100644 >> --- a/block/blk-cgroup.c >> +++ b/block/blk-cgroup.c >> @@ -23,20 +23,6 @@ static LIST_HEAD(blkio_list); >> struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT }; >> EXPORT_SYMBOL_GPL(blkio_root_cgroup); >> >> -bool blkiocg_css_tryget(struct blkio_cgroup *blkcg) >> -{ >> - if (!css_tryget(&blkcg->css)) >> - return false; >> - return true; >> -} >> -EXPORT_SYMBOL_GPL(blkiocg_css_tryget); >> - >> -void blkiocg_css_put(struct blkio_cgroup *blkcg) >> -{ >> - css_put(&blkcg->css); >> -} >> -EXPORT_SYMBOL_GPL(blkiocg_css_put); >> - >> struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup) >> { >> return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id), >> diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h >> index 4d316df..84bf745 100644 >> --- a/block/blk-cgroup.h >> +++ b/block/blk-cgroup.h >> @@ -43,9 +43,6 @@ struct blkio_group { >> unsigned long sectors; >> }; >> >> -extern bool blkiocg_css_tryget(struct blkio_cgroup *blkcg); >> -extern void blkiocg_css_put(struct blkio_cgroup *blkcg); >> - >> typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg); >> typedef void (blkio_update_group_weight_fn) (struct blkio_group *blkg, >> unsigned int weight); >> diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c >> index e2f8046..5d6b427 100644 >> --- a/block/cfq-iosched.c >> +++ b/block/cfq-iosched.c >> @@ -958,10 +958,6 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create) >> struct backing_dev_info *bdi = &cfqd->queue->backing_dev_info; >> unsigned int major, minor; >> >> - /* Do we need to take this reference */ >> - if (!blkiocg_css_tryget(blkcg)) >> - return NULL;; >> - >> cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key)); >> if (cfqg || !create) >> goto done; >> @@ -992,7 +988,6 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create) >> hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list); >> >> done: >> - blkiocg_css_put(blkcg); >> return cfqg; >> } >> >> -- >> 1.5.4.rc3 >> > > > -- 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/