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From: Waiman Long <longman@redhat.com>
To: Tejun Heo <tj@kernel.org>, Jens Axboe <axboe@kernel.dk>
Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org, Ming Lei <ming.lei@redhat.com>,
	Waiman Long <longman@redhat.com>
Subject: [PATCH v5 2/3] blk-cgroup: Return -ENOMEM directly in blkcg_css_alloc() error path
Date: Thu,  2 Jun 2022 09:35:42 -0400	[thread overview]
Message-ID: <20220602133543.128088-3-longman@redhat.com> (raw)
In-Reply-To: <20220601211824.89626-1-longman@redhat.com>

For blkcg_css_alloc(), the only error that will be returned is -ENOMEM.
Simplify error handling code by returning this error directly instead
of setting an intermediate "ret" variable.

Signed-off-by: Waiman Long <longman@redhat.com>
---
 block/blk-cgroup.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index acd9b0aa8dc8..9021f75fc752 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1177,7 +1177,6 @@ static struct cgroup_subsys_state *
 blkcg_css_alloc(struct cgroup_subsys_state *parent_css)
 {
 	struct blkcg *blkcg;
-	struct cgroup_subsys_state *ret;
 	int i;
 
 	mutex_lock(&blkcg_pol_mutex);
@@ -1186,10 +1185,8 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css)
 		blkcg = &blkcg_root;
 	} else {
 		blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL);
-		if (!blkcg) {
-			ret = ERR_PTR(-ENOMEM);
+		if (!blkcg)
 			goto unlock;
-		}
 	}
 
 	for (i = 0; i < BLKCG_MAX_POLS ; i++) {
@@ -1206,10 +1203,9 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css)
 			continue;
 
 		cpd = pol->cpd_alloc_fn(GFP_KERNEL);
-		if (!cpd) {
-			ret = ERR_PTR(-ENOMEM);
+		if (!cpd)
 			goto free_pd_blkcg;
-		}
+
 		blkcg->cpd[i] = cpd;
 		cpd->blkcg = blkcg;
 		cpd->plid = i;
@@ -1238,7 +1234,7 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css)
 		kfree(blkcg);
 unlock:
 	mutex_unlock(&blkcg_pol_mutex);
-	return ret;
+	return ERR_PTR(-ENOMEM);
 }
 
 static int blkcg_css_online(struct cgroup_subsys_state *css)
-- 
2.31.1


  parent reply	other threads:[~2022-06-02 13:36 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-01 21:18 [PATCH v3 0/2] blk-cgroup: Optimize blkcg_rstat_flush() Waiman Long
2022-06-01 21:18 ` [PATCH v3 1/2] blk-cgroup: Correctly free percpu iostat_cpu in blkg on error exit Waiman Long
2022-06-01 21:18 ` [PATCH v3 2/2] blk-cgroup: Optimize blkcg_rstat_flush() Waiman Long
2022-06-01 21:26   ` Tejun Heo
2022-06-01 21:30     ` Waiman Long
2022-06-02  6:32   ` kernel test robot
2022-06-02  1:54 ` [PATCH v4 " Waiman Long
2022-06-02 13:35 ` [PATCH v5 0/3] " Waiman Long
2022-06-02 13:35 ` [PATCH v5 1/3] blk-cgroup: Correctly free percpu iostat_cpu in blkg on error exit Waiman Long
2022-06-02 18:54   ` [PATCH v5 4/4] blk-cgroup: Document the design of new lockless iostat_cpu list Waiman Long
2022-06-02 19:05     ` Tejun Heo
2022-06-02 19:12       ` Waiman Long
2022-06-02 13:35 ` Waiman Long [this message]
2022-06-02 16:16   ` [PATCH v5 2/3] blk-cgroup: Return -ENOMEM directly in blkcg_css_alloc() error path Tejun Heo
2022-06-02 17:17     ` Waiman Long
2022-06-02 13:35 ` [PATCH v5 3/3] blk-cgroup: Optimize blkcg_rstat_flush() Waiman Long
2022-06-02 16:58   ` Tejun Heo
2022-06-02 17:26     ` Waiman Long
2022-06-02 17:46       ` Tejun Heo
2022-06-02 18:18         ` Waiman Long

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