[PATCH v5 2/3] blk-cgroup: Return -ENOMEM directly in blkcg_css_alloc() error path

From: Waiman Long
Date: Thu Jun 02 2022 - 09:36:10 EST


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@xxxxxxxxxx>
---
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