[PATCH RESEND 6/7] sched/uclamp: Fix a uninitialized variable warnings

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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>
---
 kernel/sched/fair.c | 35 ++++++++++++++++-------------------
 1 file changed, 16 insertions(+), 19 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a9ae621d58cb..1a78a7882868 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6977,14 +6977,16 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
 		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;
 
@@ -7000,24 +7002,19 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
 			 * 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;
-- 
2.25.1




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