[PATCH 7/7] sched/fair: Rename weighted_cpuload() to cpu_load()

From: Dietmar Eggemann
Date: Mon May 27 2019 - 02:25:05 EST


This is done to align the per cpu (i.e. per rq) load with the util
counterpart (cpu_util(int cpu)). The term 'weighted' is not needed
since there is no 'unweighted' load to distinguish it from.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
---
kernel/sched/fair.c | 44 ++++++++++++++++++++------------------------
1 file changed, 20 insertions(+), 24 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a33f196703a7..f6d0aad13090 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1466,7 +1466,7 @@ bool should_numa_migrate_memory(struct task_struct *p, struct page * page,
group_faults_cpu(ng, src_nid) * group_faults(p, dst_nid) * 4;
}

-static unsigned long weighted_cpuload(struct rq *rq);
+static unsigned long cpu_load(int cpu);

/* Cached statistics for all CPUs within a node */
struct numa_stats {
@@ -1485,9 +1485,7 @@ static void update_numa_stats(struct numa_stats *ns, int nid)

memset(ns, 0, sizeof(*ns));
for_each_cpu(cpu, cpumask_of_node(nid)) {
- struct rq *rq = cpu_rq(cpu);
-
- ns->load += weighted_cpuload(rq);
+ ns->load += cpu_load(cpu);
ns->compute_capacity += capacity_of(cpu);
}

@@ -5334,9 +5332,9 @@ static struct {

#endif /* CONFIG_NO_HZ_COMMON */

-static unsigned long weighted_cpuload(struct rq *rq)
+static unsigned long cpu_load(int cpu)
{
- return cfs_rq_runnable_load_avg(&rq->cfs);
+ return cfs_rq_runnable_load_avg(&cpu_rq(cpu)->cfs);
}

static unsigned long capacity_of(int cpu)
@@ -5348,7 +5346,7 @@ static unsigned long cpu_avg_load_per_task(int cpu)
{
struct rq *rq = cpu_rq(cpu);
unsigned long nr_running = READ_ONCE(rq->cfs.h_nr_running);
- unsigned long load_avg = weighted_cpuload(rq);
+ unsigned long load_avg = cpu_load(cpu);

if (nr_running)
return load_avg / nr_running;
@@ -5446,7 +5444,7 @@ wake_affine_weight(struct sched_domain *sd, struct task_struct *p,
s64 this_eff_load, prev_eff_load;
unsigned long task_load;

- this_eff_load = weighted_cpuload(cpu_rq(this_cpu));
+ this_eff_load = cpu_load(this_cpu);

if (sync) {
unsigned long current_load = task_h_load(current);
@@ -5464,7 +5462,7 @@ wake_affine_weight(struct sched_domain *sd, struct task_struct *p,
this_eff_load *= 100;
this_eff_load *= capacity_of(prev_cpu);

- prev_eff_load = weighted_cpuload(cpu_rq(this_cpu));
+ prev_eff_load = cpu_load(this_cpu);
prev_eff_load -= task_load;
if (sched_feat(WA_BIAS))
prev_eff_load *= 100 + (sd->imbalance_pct - 100) / 2;
@@ -5552,7 +5550,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
max_spare_cap = 0;

for_each_cpu(i, sched_group_span(group)) {
- load = weighted_cpuload(cpu_rq(i));
+ load = cpu_load(i);
runnable_load += load;

avg_load += cfs_rq_load_avg(&cpu_rq(i)->cfs);
@@ -5688,7 +5686,7 @@ find_idlest_group_cpu(struct sched_group *group, struct task_struct *p, int this
shallowest_idle_cpu = i;
}
} else if (shallowest_idle_cpu == -1) {
- load = weighted_cpuload(cpu_rq(i));
+ load = cpu_load(i);
if (load < min_load) {
min_load = load;
least_loaded_cpu = i;
@@ -7259,8 +7257,8 @@ static struct task_struct *detach_one_task(struct lb_env *env)
static const unsigned int sched_nr_migrate_break = 32;

/*
- * detach_tasks() -- tries to detach up to imbalance weighted load from
- * busiest_rq, as part of a balancing operation within domain "sd".
+ * detach_tasks() -- tries to detach up to imbalance load from busiest_rq,
+ * as part of a balancing operation within domain "sd".
*
* Returns number of detached tasks if successful and 0 otherwise.
*/
@@ -7326,8 +7324,7 @@ static int detach_tasks(struct lb_env *env)
#endif

/*
- * We only want to steal up to the prescribed amount of
- * weighted load.
+ * We only want to steal up to the prescribed amount of load.
*/
if (env->imbalance <= 0)
break;
@@ -7931,7 +7928,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
if ((env->flags & LBF_NOHZ_STATS) && update_nohz_stats(rq, false))
env->flags |= LBF_NOHZ_AGAIN;

- sgs->group_load += weighted_cpuload(rq);
+ sgs->group_load += cpu_load(i);
sgs->group_util += cpu_util(i);
sgs->sum_nr_running += rq->cfs.h_nr_running;

@@ -8385,8 +8382,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
* find_busiest_group - Returns the busiest group within the sched_domain
* if there is an imbalance.
*
- * Also calculates the amount of weighted load which should be moved
- * to restore balance.
+ * Also calculates the amount of load which should be moved to restore balance.
*
* @env: The load balancing environment.
*
@@ -8558,11 +8554,11 @@ static struct rq *find_busiest_queue(struct lb_env *env,
rq->nr_running == 1)
continue;

- wl = weighted_cpuload(rq);
+ wl = cpu_load(i);

/*
- * When comparing with imbalance, use weighted_cpuload()
- * which is not scaled with the CPU capacity.
+ * When comparing with imbalance, use cpu_load() which is not
+ * scaled with the CPU capacity.
*/

if (rq->nr_running == 1 && wl > env->imbalance &&
@@ -8571,9 +8567,9 @@ static struct rq *find_busiest_queue(struct lb_env *env,

/*
* For the load comparisons with the other CPU's, consider
- * the weighted_cpuload() scaled with the CPU capacity, so
- * that the load can be moved away from the CPU that is
- * potentially running at a lower capacity.
+ * the cpu_load() scaled with the CPU capacity, so that the
+ * load can be moved away from the CPU that is potentially
+ * running at a lower capacity.
*
* Thus we're looking for max(wl_i / capacity_i), crosswise
* multiplication to rid ourselves of the division works out
--
2.17.1