linux-kernel - [PATCH] kernel/sched/cputime: Fix unused value in cputime

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Date:   Wed, 20 Jul 2022 18:29:56 +0800
From:   zengjx95@...il.com
To:     mingo@...hat.com, peterz@...radead.org, juri.lelli@...hat.com,
        vincent.guittot@...aro.org, dietmar.eggemann@....com,
        rostedt@...dmis.org, bsegall@...gle.com, mgorman@...e.de,
        bristot@...hat.com, vschneid@...hat.com
Cc:     linux-kernel@...r.kernel.org,
        Zeng Jingxiang <linuszeng@...cent.com>
Subject: [PATCH] kernel/sched/cputime: Fix unused value in cputime_adjust()

From: Zeng Jingxiang <linuszeng@...cent.com>

Coverity warns uf an unused value:

assigned_value: Assign the value of the variable rtime to utime here,
but that stored value is overwritten before it can be used.
568	if (stime == 0) {
569		utime = rtime;
570		goto update;
571	}

value_overwrite: Overwriting previous write to utime with
the value of expression rtime - stime.
592	utime = rtime - stime;

Signed-off-by: Zeng Jingxiang <linuszeng@...cent.com>
---
 kernel/sched/cputime.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 78a233d43757..531df8b29e6d 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -565,10 +565,8 @@ void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
 	 * Once a task gets some ticks, the monotonicity code at 'update:'
 	 * will ensure things converge to the observed ratio.
 	 */
-	if (stime == 0) {
-		utime = rtime;
+	if (stime == 0)
 		goto update;
-	}
 
 	if (utime == 0) {
 		stime = rtime;
-- 
2.27.0