diff mbox series

[v3,1/2] sched/uclamp: Fix a uninitialized variable warnings

Message ID 20230112122708.330667-2-qyousef@layalina.io
State Accepted
Commit e26fd28db82899be71b4b949527373d0a6be1e65
Headers show
Series Fixes for uclamp and capacity inversion detection | expand

Commit Message

Qais Yousef Jan. 12, 2023, 12:27 p.m. UTC
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@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Qais Yousef (Google) <qyousef@layalina.io>
---
 kernel/sched/fair.c | 35 ++++++++++++++++-------------------
 1 file changed, 16 insertions(+), 19 deletions(-)

Comments

Vincent Guittot Jan. 13, 2023, 8:13 a.m. UTC | #1
On Thu, 12 Jan 2023 at 13:27, Qais Yousef <qyousef@layalina.io> wrote:
>
> 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@intel.com>
> Reported-by: Dan Carpenter <error27@gmail.com>
> Signed-off-by: Qais Yousef (Google) <qyousef@layalina.io>

Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>

> ---
>  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 e9d906a9bba9..5a8e75d4a17b 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -7353,10 +7353,10 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
>         eenv_task_busy_time(&eenv, p, prev_cpu);
>
>         for (; pd; pd = pd->next) {
> +               unsigned long util_min = p_util_min, util_max = p_util_max;
>                 unsigned long cpu_cap, cpu_thermal_cap, util;
>                 unsigned long cur_delta, max_spare_cap = 0;
>                 unsigned long rq_util_min, rq_util_max;
> -               unsigned long util_min, util_max;
>                 unsigned long prev_spare_cap = 0;
>                 int max_spare_cap_cpu = -1;
>                 unsigned long base_energy;
> @@ -7375,6 +7375,8 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
>                 eenv.pd_cap = 0;
>
>                 for_each_cpu(cpu, cpus) {
> +                       struct rq *rq = cpu_rq(cpu);
> +
>                         eenv.pd_cap += cpu_thermal_cap;
>
>                         if (!cpumask_test_cpu(cpu, sched_domain_span(sd)))
> @@ -7393,24 +7395,19 @@ 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
>
diff mbox series

Patch

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index e9d906a9bba9..5a8e75d4a17b 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7353,10 +7353,10 @@  static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
 	eenv_task_busy_time(&eenv, p, prev_cpu);
 
 	for (; pd; pd = pd->next) {
+		unsigned long util_min = p_util_min, util_max = p_util_max;
 		unsigned long cpu_cap, cpu_thermal_cap, util;
 		unsigned long cur_delta, max_spare_cap = 0;
 		unsigned long rq_util_min, rq_util_max;
-		unsigned long util_min, util_max;
 		unsigned long prev_spare_cap = 0;
 		int max_spare_cap_cpu = -1;
 		unsigned long base_energy;
@@ -7375,6 +7375,8 @@  static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
 		eenv.pd_cap = 0;
 
 		for_each_cpu(cpu, cpus) {
+			struct rq *rq = cpu_rq(cpu);
+
 			eenv.pd_cap += cpu_thermal_cap;
 
 			if (!cpumask_test_cpu(cpu, sched_domain_span(sd)))
@@ -7393,24 +7395,19 @@  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;