This is a note to let you know that I've just added the patch titled
sched/uclamp: Fix a uninitialized variable warnings
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
sched-uclamp-fix-a-uninitialized-variable-warnings.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From stable-owner@xxxxxxxxxxxxxxx Tue Apr 18 16:06:10 2023
From: Qais Yousef <qyousef@xxxxxxxxxxx>
Date: Tue, 18 Apr 2023 15:05:46 +0100
Subject: sched/uclamp: Fix a uninitialized variable warnings
To: stable@xxxxxxxxxxxxxxx, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>, Vincent Guittot <vincent.guittot@xxxxxxxxxx>, Dietmar Eggemann <dietmar.eggemann@xxxxxxx>, Qais Yousef <qyousef@xxxxxxxxxxx>, kernel test robot <lkp@xxxxxxxxx>, Dan Carpenter <error27@xxxxxxxxx>
Message-ID: <20230418140547.88035-7-qyousef@xxxxxxxxxxx>
From: Qais Yousef <qyousef@xxxxxxxxxxx>
commit e26fd28db82899be71b4b949527373d0a6be1e65 upstream.
Addresses the following warnings:
> config: riscv-randconfig-m031-20221111
> compiler: riscv64-linux-gcc (GCC) 12.1.0
>
> smatch warnings:
> kernel/sched/fair.c:7263 find_energy_efficient_cpu() error: uninitialized symbol 'util_min'.
> kernel/sched/fair.c:7263 find_energy_efficient_cpu() error: uninitialized symbol 'util_max'.
Fixes: 244226035a1f ("sched/uclamp: Fix fits_capacity() check in feec()")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <error27@xxxxxxxxx>
Signed-off-by: Qais Yousef (Google) <qyousef@xxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230112122708.330667-2-qyousef@xxxxxxxxxxx
(cherry picked from commit e26fd28db82899be71b4b949527373d0a6be1e65)
[Conflict in kernel/sched/fair.c due to new automatic variables being
added on master vs 5.15]
Signed-off-by: Qais Yousef (Google) <qyousef@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/sched/fair.c | 35 ++++++++++++++++-------------------
1 file changed, 16 insertions(+), 19 deletions(-)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7024,14 +7024,16 @@ static int find_energy_efficient_cpu(str
goto unlock;
for (; pd; pd = pd->next) {
+ unsigned long util_min = p_util_min, util_max = p_util_max;
unsigned long cur_delta, spare_cap, max_spare_cap = 0;
unsigned long rq_util_min, rq_util_max;
- unsigned long util_min, util_max;
bool compute_prev_delta = false;
unsigned long base_energy_pd;
int max_spare_cap_cpu = -1;
for_each_cpu_and(cpu, perf_domain_span(pd), sched_domain_span(sd)) {
+ struct rq *rq = cpu_rq(cpu);
+
if (!cpumask_test_cpu(cpu, p->cpus_ptr))
continue;
@@ -7047,24 +7049,19 @@ static int find_energy_efficient_cpu(str
* much capacity we can get out of the CPU; this is
* aligned with sched_cpu_util().
*/
- if (uclamp_is_used()) {
- if (uclamp_rq_is_idle(cpu_rq(cpu))) {
- util_min = p_util_min;
- util_max = p_util_max;
- } else {
- /*
- * Open code uclamp_rq_util_with() except for
- * the clamp() part. Ie: apply max aggregation
- * only. util_fits_cpu() logic requires to
- * operate on non clamped util but must use the
- * max-aggregated uclamp_{min, max}.
- */
- rq_util_min = uclamp_rq_get(cpu_rq(cpu), UCLAMP_MIN);
- rq_util_max = uclamp_rq_get(cpu_rq(cpu), UCLAMP_MAX);
-
- util_min = max(rq_util_min, p_util_min);
- util_max = max(rq_util_max, p_util_max);
- }
+ if (uclamp_is_used() && !uclamp_rq_is_idle(rq)) {
+ /*
+ * Open code uclamp_rq_util_with() except for
+ * the clamp() part. Ie: apply max aggregation
+ * only. util_fits_cpu() logic requires to
+ * operate on non clamped util but must use the
+ * max-aggregated uclamp_{min, max}.
+ */
+ rq_util_min = uclamp_rq_get(rq, UCLAMP_MIN);
+ rq_util_max = uclamp_rq_get(rq, UCLAMP_MAX);
+
+ util_min = max(rq_util_min, p_util_min);
+ util_max = max(rq_util_max, p_util_max);
}
if (!util_fits_cpu(util, util_min, util_max, cpu))
continue;
Patches currently in stable-queue which might be from stable-owner@xxxxxxxxxxxxxxx are
queue-5.15/sched-fair-detect-capacity-inversion.patch
queue-5.15/sched-uclamp-make-cpu_overutilized-use-util_fits_cpu.patch
queue-5.15/sched-uclamp-fix-fits_capacity-check-in-feec.patch
queue-5.15/sched-fair-consider-capacity-inversion-in-util_fits_cpu.patch
queue-5.15/sched-fair-fixes-for-capacity-inversion-detection.patch
queue-5.15/sched-uclamp-fix-a-uninitialized-variable-warnings.patch
queue-5.15/sched-uclamp-cater-for-uclamp-in-find_energy_efficient_cpu-s-early-exit-condition.patch
