sched/fair: Pass 'rq' to weighted_cpuload()

weighted_cpuload() uses the cpu number passed to it get pointer to the
runqueue. Almost all callers of weighted_cpuload() already have the rq
pointer with them and can send that directly to weighted_cpuload(). In
some cases the callers actually get the CPU number by doing cpu_of(rq).

It would be simpler to pass rq to weighted_cpuload().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Link: http://lkml.kernel.org/r/b7720627e0576dc29b4ba3f9b6edbc913bb4f684.1495603536.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

kernel/sched/fair.c

@@ -1378,7 +1378,7 @@ 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(const int cpu);
+static unsigned long weighted_cpuload(struct rq *rq);
 static unsigned long source_load(int cpu, int type);
 static unsigned long target_load(int cpu, int type);
 static unsigned long capacity_of(int cpu);
@@ -1409,7 +1409,7 @@ static void update_numa_stats(struct numa_stats *ns, int nid)
 		struct rq *rq = cpu_rq(cpu);
 
 		ns->nr_running += rq->nr_running;
-		ns->load += weighted_cpuload(cpu);
+		ns->load += weighted_cpuload(rq);
 		ns->compute_capacity += capacity_of(cpu);
 
 		cpus++;
@@ -5125,9 +5125,9 @@ static void cpu_load_update(struct rq *this_rq, unsigned long this_load,
 }
 
 /* Used instead of source_load when we know the type == 0 */
-static unsigned long weighted_cpuload(const int cpu)
+static unsigned long weighted_cpuload(struct rq *rq)
 {
-	return cfs_rq_runnable_load_avg(&cpu_rq(cpu)->cfs);
+	return cfs_rq_runnable_load_avg(&rq->cfs);
 }
 
 #ifdef CONFIG_NO_HZ_COMMON
@@ -5172,7 +5172,7 @@ static void cpu_load_update_idle(struct rq *this_rq)
 	/*
 	 * bail if there's load or we're actually up-to-date.
 	 */
-	if (weighted_cpuload(cpu_of(this_rq)))
+	if (weighted_cpuload(this_rq))
 		return;
 
 	cpu_load_update_nohz(this_rq, READ_ONCE(jiffies), 0);
@@ -5193,7 +5193,7 @@ void cpu_load_update_nohz_start(void)
 	 * concurrently we'll exit nohz. And cpu_load write can race with
 	 * cpu_load_update_idle() but both updater would be writing the same.
 	 */
-	this_rq->cpu_load[0] = weighted_cpuload(cpu_of(this_rq));
+	this_rq->cpu_load[0] = weighted_cpuload(this_rq);
 }
 
 /*
@@ -5209,7 +5209,7 @@ void cpu_load_update_nohz_stop(void)
 	if (curr_jiffies == this_rq->last_load_update_tick)
 		return;
 
-	load = weighted_cpuload(cpu_of(this_rq));
+	load = weighted_cpuload(this_rq);
 	rq_lock(this_rq, &rf);
 	update_rq_clock(this_rq);
 	cpu_load_update_nohz(this_rq, curr_jiffies, load);
@@ -5235,7 +5235,7 @@ static void cpu_load_update_periodic(struct rq *this_rq, unsigned long load)
  */
 void cpu_load_update_active(struct rq *this_rq)
 {
-	unsigned long load = weighted_cpuload(cpu_of(this_rq));
+	unsigned long load = weighted_cpuload(this_rq);
 
 	if (tick_nohz_tick_stopped())
 		cpu_load_update_nohz(this_rq, READ_ONCE(jiffies), load);
@@ -5253,7 +5253,7 @@ void cpu_load_update_active(struct rq *this_rq)
 static unsigned long source_load(int cpu, int type)
 {
 	struct rq *rq = cpu_rq(cpu);
-	unsigned long total = weighted_cpuload(cpu);
+	unsigned long total = weighted_cpuload(rq);
 
 	if (type == 0 || !sched_feat(LB_BIAS))
 		return total;
@@ -5268,7 +5268,7 @@ static unsigned long source_load(int cpu, int type)
 static unsigned long target_load(int cpu, int type)
 {
 	struct rq *rq = cpu_rq(cpu);
-	unsigned long total = weighted_cpuload(cpu);
+	unsigned long total = weighted_cpuload(rq);
 
 	if (type == 0 || !sched_feat(LB_BIAS))
 		return total;
@@ -5290,7 +5290,7 @@ 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(cpu);
+	unsigned long load_avg = weighted_cpuload(rq);
 
 	if (nr_running)
 		return load_avg / nr_running;
@@ -5550,7 +5550,7 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
 				shallowest_idle_cpu = i;
 			}
 		} else if (shallowest_idle_cpu == -1) {
-			load = weighted_cpuload(i);
+			load = weighted_cpuload(cpu_rq(i));
 			if (load < min_load || (load == min_load && i == this_cpu)) {
 				min_load = load;
 				least_loaded_cpu = i;
@@ -7363,7 +7363,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
 		sgs->nr_numa_running += rq->nr_numa_running;
 		sgs->nr_preferred_running += rq->nr_preferred_running;
 #endif
-		sgs->sum_weighted_load += weighted_cpuload(i);
+		sgs->sum_weighted_load += weighted_cpuload(rq);
 		/*
 		 * No need to call idle_cpu() if nr_running is not 0
 		 */
@@ -7892,7 +7892,7 @@ static struct rq *find_busiest_queue(struct lb_env *env,
 
 		capacity = capacity_of(i);
 
-		wl = weighted_cpuload(i);
+		wl = weighted_cpuload(rq);
 
 		/*
 		 * When comparing with imbalance, use weighted_cpuload()