[v5,4/5] sched/fair: Check the SD_ASYM_PACKING flag in sched_use_asym_prio()

Message ID 20240210113924.1130448-4-alexs@kernel.org
State New
Headers
Series [v5,1/5] sched/topology: Remove duplicate descriptions from TOPOLOGY_SD_FLAGS |

Commit Message

alexs@kernel.org Feb. 10, 2024, 11:39 a.m. UTC
  From: Alex Shi <alexs@kernel.org>

sched_use_asym_prio() checks whether CPU priorities should be used. It
makes sense to check for the SD_ASYM_PACKING() inside the function.
Since both sched_asym() and sched_group_asym() use sched_use_asym_prio(),
remove the now superfluous checks for the flag in various places.

Tested-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Alex Shi <alexs@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Reviewed-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
---
 kernel/sched/fair.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)
  

Comments

Vincent Guittot Feb. 13, 2024, 5:02 p.m. UTC | #1
On Sat, 10 Feb 2024 at 12:36, <alexs@kernel.org> wrote:
>
> From: Alex Shi <alexs@kernel.org>
>
> sched_use_asym_prio() checks whether CPU priorities should be used. It
> makes sense to check for the SD_ASYM_PACKING() inside the function.
> Since both sched_asym() and sched_group_asym() use sched_use_asym_prio(),
> remove the now superfluous checks for the flag in various places.
>
> Tested-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
> Signed-off-by: Alex Shi <alexs@kernel.org>
> Cc: linux-kernel@vger.kernel.org
> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
> Cc: Ben Segall <bsegall@google.com>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
> Cc: Valentin Schneider <vschneid@redhat.com>
> Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
> Cc: Vincent Guittot <vincent.guittot@linaro.org>
> Cc: Juri Lelli <juri.lelli@redhat.com>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Ingo Molnar <mingo@redhat.com>
> Reviewed-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>

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

> ---
>  kernel/sched/fair.c | 16 +++++++---------
>  1 file changed, 7 insertions(+), 9 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 426eda9eda57..cd1ec57c0b7b 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -9740,6 +9740,9 @@ group_type group_classify(unsigned int imbalance_pct,
>   */
>  static bool sched_use_asym_prio(struct sched_domain *sd, int cpu)
>  {
> +       if (!(sd->flags & SD_ASYM_PACKING))
> +               return false;
> +
>         if (!sched_smt_active())
>                 return true;
>
> @@ -9933,11 +9936,9 @@ static inline void update_sg_lb_stats(struct lb_env *env,
>         sgs->group_weight = group->group_weight;
>
>         /* Check if dst CPU is idle and preferred to this group */
> -       if (!local_group && env->sd->flags & SD_ASYM_PACKING &&
> -           env->idle != CPU_NOT_IDLE && sgs->sum_h_nr_running &&
> -           sched_group_asym(env, sgs, group)) {
> +       if (!local_group && env->idle != CPU_NOT_IDLE && sgs->sum_h_nr_running &&
> +           sched_group_asym(env, sgs, group))
>                 sgs->group_asym_packing = 1;
> -       }
>
>         /* Check for loaded SMT group to be balanced to dst CPU */
>         if (!local_group && smt_balance(env, sgs, group))
> @@ -11033,9 +11034,7 @@ static struct rq *find_busiest_queue(struct lb_env *env,
>                  * If balancing between cores, let lower priority CPUs help
>                  * SMT cores with more than one busy sibling.
>                  */
> -               if ((env->sd->flags & SD_ASYM_PACKING) &&
> -                   sched_asym(env->sd, i, env->dst_cpu) &&
> -                   nr_running == 1)
> +               if (sched_asym(env->sd, i, env->dst_cpu) && nr_running == 1)
>                         continue;
>
>                 switch (env->migration_type) {
> @@ -11131,8 +11130,7 @@ asym_active_balance(struct lb_env *env)
>          * the lower priority @env::dst_cpu help it. Do not follow
>          * CPU priority.
>          */
> -       return env->idle != CPU_NOT_IDLE && (env->sd->flags & SD_ASYM_PACKING) &&
> -              sched_use_asym_prio(env->sd, env->dst_cpu) &&
> +       return env->idle != CPU_NOT_IDLE && sched_use_asym_prio(env->sd, env->dst_cpu) &&
>                (sched_asym_prefer(env->dst_cpu, env->src_cpu) ||
>                 !sched_use_asym_prio(env->sd, env->src_cpu));
>  }
> --
> 2.43.0
>
  

Patch

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 426eda9eda57..cd1ec57c0b7b 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9740,6 +9740,9 @@  group_type group_classify(unsigned int imbalance_pct,
  */
 static bool sched_use_asym_prio(struct sched_domain *sd, int cpu)
 {
+	if (!(sd->flags & SD_ASYM_PACKING))
+		return false;
+
 	if (!sched_smt_active())
 		return true;
 
@@ -9933,11 +9936,9 @@  static inline void update_sg_lb_stats(struct lb_env *env,
 	sgs->group_weight = group->group_weight;
 
 	/* Check if dst CPU is idle and preferred to this group */
-	if (!local_group && env->sd->flags & SD_ASYM_PACKING &&
-	    env->idle != CPU_NOT_IDLE && sgs->sum_h_nr_running &&
-	    sched_group_asym(env, sgs, group)) {
+	if (!local_group && env->idle != CPU_NOT_IDLE && sgs->sum_h_nr_running &&
+	    sched_group_asym(env, sgs, group))
 		sgs->group_asym_packing = 1;
-	}
 
 	/* Check for loaded SMT group to be balanced to dst CPU */
 	if (!local_group && smt_balance(env, sgs, group))
@@ -11033,9 +11034,7 @@  static struct rq *find_busiest_queue(struct lb_env *env,
 		 * If balancing between cores, let lower priority CPUs help
 		 * SMT cores with more than one busy sibling.
 		 */
-		if ((env->sd->flags & SD_ASYM_PACKING) &&
-		    sched_asym(env->sd, i, env->dst_cpu) &&
-		    nr_running == 1)
+		if (sched_asym(env->sd, i, env->dst_cpu) && nr_running == 1)
 			continue;
 
 		switch (env->migration_type) {
@@ -11131,8 +11130,7 @@  asym_active_balance(struct lb_env *env)
 	 * the lower priority @env::dst_cpu help it. Do not follow
 	 * CPU priority.
 	 */
-	return env->idle != CPU_NOT_IDLE && (env->sd->flags & SD_ASYM_PACKING) &&
-	       sched_use_asym_prio(env->sd, env->dst_cpu) &&
+	return env->idle != CPU_NOT_IDLE && sched_use_asym_prio(env->sd, env->dst_cpu) &&
 	       (sched_asym_prefer(env->dst_cpu, env->src_cpu) ||
 		!sched_use_asym_prio(env->sd, env->src_cpu));
 }