[PATCH] sched: remove redundant assignment to "rt_rq" in update_curr_rt(...)

[PATCH] sched: remove redundant assignment to "rt_rq" in update_curr_rt(...)

[Giedrius Rekasius]

Variable "rt_rq" is used only in block "for_each_sched_rt_entity" so the
value assigned to it at the beginning of the update_curr_rt(...) gets
overwritten without ever being read. Remove redundant assignment and
move variable declaration to the block in which it is being used.

Signed-off-by: Giedrius Rekasius <giedrius.rekasius@gmail.com>
---
 kernel/sched/rt.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index bd2267a..7e0ea78 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -885,7 +885,6 @@ static void update_curr_rt(struct rq *rq)
 {
 	struct task_struct *curr = rq->curr;
 	struct sched_rt_entity *rt_se = &curr->rt;
-	struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
 	u64 delta_exec;
 
 	if (curr->sched_class != &rt_sched_class)
@@ -910,7 +909,7 @@ static void update_curr_rt(struct rq *rq)
 		return;
 
 	for_each_sched_rt_entity(rt_se) {
-		rt_rq = rt_rq_of_se(rt_se);
+		struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
 
 		if (sched_rt_runtime(rt_rq) != RUNTIME_INF) {
 			raw_spin_lock(&rt_rq->rt_runtime_lock);
-- 
1.9.3

[PATCH] sched: remove redundant assignment to variable utime

[Colin King]

From: Colin Ian King <colin.king@canonical.com>

The variable utime is being assigned a value however this is never
read and later it is being reassigned to a new value. The assignment
is redundant and hence can be removed.

Addresses-Coverity: ("Unused Value")
Signed-off-by: Colin Ian King <colin.king@canonical.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 ba4a143bdcf3..ad647711ffb8 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -616,10 +616,8 @@ void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
 	 * Once a task gets some ticks, the monotonicy 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;
-- 
2.20.1

Re: [PATCH] sched: remove redundant assignment to variable utime

[Peter Zijlstra]

On Sat, May 11, 2019 at 02:18:49PM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> The variable utime is being assigned a value however this is never
> read and later it is being reassigned to a new value. The assignment
> is redundant and hence can be removed.
> 
> Addresses-Coverity: ("Unused Value")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>

Argh. not again.. still no.