[PATCH v3 3/4] sched/fair: packing func sched_use_asym_prio()/sched_asym_prefer()

alexs
2024-02-01T11:52:03Z

From: Alex Shi <alexs@kernel.org>

Consolidate the functions sched_use_asym_prio() and sched_asym_prefer()
into one. and rename sched_asym() as sched_group_asym().
This makes the code easier to read. No functional changes.

Signed-off-by: Alex Shi <alexs@kernel.org>
To: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
To: Valentin Schneider <vschneid@redhat.com>
To: Vincent Guittot <vincent.guittot@linaro.org>
To: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@redhat.com>
---
kernel/sched/fair.c | 35 ++++++++++++++++++-----------------
1 file changed, 18 insertions(+), 17 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 8d70417f5125..44fd5e2ca642 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9747,8 +9747,15 @@ static bool sched_use_asym_prio(struct sched_domain *sd, int cpu)
return sd->flags & SD_SHARE_CPUCAPACITY || is_core_idle(cpu);
}

+static inline bool sched_asym(struct sched_domain *sd, int dst_cpu, int src_cpu)
+{
+ /* Check if asym balance applicable, then check priorities.*/
+ return sched_use_asym_prio(sd, dst_cpu) &&
+ sched_asym_prefer(dst_cpu, src_cpu);
+}
+
/**
- * sched_asym - Check if the destination CPU can do asym_packing load balance
+ * sched_group_asym - Check if the destination CPU can do asym_packing balance
* @env: The load balancing environment
* @sgs: Load-balancing statistics of the candidate busiest group
* @group: The candidate busiest group
@@ -9768,22 +9775,18 @@ static bool sched_use_asym_prio(struct sched_domain *sd, int cpu)
* otherwise.
*/
static inline bool
-sched_asym(struct lb_env *env, struct sg_lb_stats *sgs, struct sched_group *group)
+sched_group_asym(struct lb_env *env, struct sg_lb_stats *sgs, struct sched_group *group)
{
- /* Ensure that the whole local core is idle, if applicable. */
- if (!sched_use_asym_prio(env->sd, env->dst_cpu))
- return false;
-
/*
- * CPU priorities does not make sense for SMT cores with more than one
+ * CPU priorities do not make sense for SMT cores with more than one
* busy sibling.
*/
- if (group->flags & SD_SHARE_CPUCAPACITY) {
- if (sgs->group_weight - sgs->idle_cpus != 1)
- return false;
- }

- return sched_asym_prefer(env->dst_cpu, group->asym_prefer_cpu);
+ if ((group->flags & SD_SHARE_CPUCAPACITY) &&
+ (sgs->group_weight - sgs->idle_cpus != 1))
+ return false;
+
+ return sched_asym(env->sd, env->dst_cpu, group->asym_prefer_cpu);
}

/* One group has more than one SMT CPU while the other group does not */
@@ -9939,7 +9942,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
/* 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_asym(env, sgs, group)) {
+ sched_group_asym(env, sgs, group)) {
sgs->group_asym_packing = 1;
}

@@ -11038,8 +11041,7 @@ static struct rq *find_busiest_queue(struct lb_env *env,
* SMT cores with more than one busy sibling.
*/
if ((env->sd->flags & SD_ASYM_PACKING) &&
- sched_use_asym_prio(env->sd, i) &&
- sched_asym_prefer(i, env->dst_cpu) &&
+ sched_asym(env->sd, i, env->dst_cpu) &&
nr_running == 1)
continue;

@@ -11909,8 +11911,7 @@ static void nohz_balancer_kick(struct rq *rq)
* preferred CPU must be idle.
*/
for_each_cpu_and(i, sched_domain_span(sd), nohz.idle_cpus_mask) {
- if (sched_use_asym_prio(sd, i) &&
- sched_asym_prefer(i, cpu)) {
+ if (sched_asym(sd, i, cpu)) {
flags = NOHZ_STATS_KICK | NOHZ_BALANCE_KICK;
goto unlock;
}
--
2.43.0