[tip: sched/core] sched: Simplify sysctl_sched_uclamp_handler()

From: tip-bot2 for Peter Zijlstra
Date: Mon Aug 14 2023 - 11:08:57 EST


The following commit has been merged into the sched/core branch of tip:

Commit-ID: 0f92cdf36f848f1c077924f857a49789e00331c0
Gitweb: https://git.kernel.org/tip/0f92cdf36f848f1c077924f857a49789e00331c0
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Tue, 01 Aug 2023 22:41:23 +02:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 14 Aug 2023 17:01:24 +02:00

sched: Simplify sysctl_sched_uclamp_handler()

Use guards to reduce gotos and simplify control flow.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Valentin Schneider <vschneid@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230801211811.896559109@xxxxxxxxxxxxx
---
kernel/sched/core.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 6cda296..6e8a8e9 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1827,7 +1827,8 @@ static int sysctl_sched_uclamp_handler(struct ctl_table *table, int write,
int old_min, old_max, old_min_rt;
int result;

- mutex_lock(&uclamp_mutex);
+ guard(mutex)(&uclamp_mutex);
+
old_min = sysctl_sched_uclamp_util_min;
old_max = sysctl_sched_uclamp_util_max;
old_min_rt = sysctl_sched_uclamp_util_min_rt_default;
@@ -1836,7 +1837,7 @@ static int sysctl_sched_uclamp_handler(struct ctl_table *table, int write,
if (result)
goto undo;
if (!write)
- goto done;
+ return 0;

if (sysctl_sched_uclamp_util_min > sysctl_sched_uclamp_util_max ||
sysctl_sched_uclamp_util_max > SCHED_CAPACITY_SCALE ||
@@ -1872,16 +1873,12 @@ static int sysctl_sched_uclamp_handler(struct ctl_table *table, int write,
* Otherwise, keep it simple and do just a lazy update at each next
* task enqueue time.
*/
-
- goto done;
+ return 0;

undo:
sysctl_sched_uclamp_util_min = old_min;
sysctl_sched_uclamp_util_max = old_max;
sysctl_sched_uclamp_util_min_rt_default = old_min_rt;
-done:
- mutex_unlock(&uclamp_mutex);
-
return result;
}
#endif