From mboxrd@z Thu Jan 1 00:00:00 1970 From: Waiman Long Subject: [PATCH v6 1/3] blk-cgroup: Correctly free percpu iostat_cpu in blkg on error exit Date: Thu, 2 Jun 2022 15:20:18 -0400 Message-ID: <20220602192020.166940-2-longman@redhat.com> References: <20220602192020.166940-1-longman@redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1654197640; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=YXLuT1Yk9DAXTYl5NoX/oMeS35ik4rQo8uu3jun7bK8=; b=SlydR8JkK+NRbJYZngxHyk2MR81LTG/YaheI4HbhlIXL/yoaw7qS1GMnpNYRlkEXsG5XTP F/8VppGB3oWOZO0p/MEL9VsTWSi1jxCN1ZQLEAcBohHPLQ0A6zcNJb6cX5jWaOQaqX1Pjn sPh58ZcVJhulCUYX0O2K1HYGAyZkyfE= In-Reply-To: <20220602192020.166940-1-longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: Tejun Heo , Jens Axboe Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ming Lei , Waiman Long Commit f73316482977 ("blk-cgroup: reimplement basic IO stats using cgroup rstat") changes block cgroup IO stats to use the rstat APIs. It added a new percpu iostat_cpu field into blkg. The blkg_alloc() was modified to allocate the new percpu iostat_cpu but didn't free it when an error happened. Fix this by freeing the percpu iostat_cpu on error exit. Fixes: f73316482977 ("blk-cgroup: reimplement basic IO stats using cgroup rstat") Signed-off-by: Waiman Long Acked-by: Tejun Heo --- block/blk-cgroup.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 40161a3f68d0..acd9b0aa8dc8 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -219,11 +219,11 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q, return NULL; if (percpu_ref_init(&blkg->refcnt, blkg_release, 0, gfp_mask)) - goto err_free; + goto err_free_blkg; blkg->iostat_cpu = alloc_percpu_gfp(struct blkg_iostat_set, gfp_mask); if (!blkg->iostat_cpu) - goto err_free; + goto err_free_blkg; if (!blk_get_queue(q)) goto err_free; @@ -259,6 +259,9 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q, return blkg; err_free: + free_percpu(blkg->iostat_cpu); + +err_free_blkg: blkg_free(blkg); return NULL; } -- 2.31.1