1 files changed, 88 insertions, 38 deletions

diff --git a/kernel/sched/pelt.c b/kernel/sched/pelt.c
index bd006b79b360..0f310768260c 100644
--- a/kernel/sched/pelt.c
+++ b/kernel/sched/pelt.c
@@ -24,12 +24,6 @@
  *  Author: Vincent Guittot <vincent.guittot@linaro.org>
  */
 
-#include <linux/sched.h>
-#include "sched.h"
-#include "pelt.h"
-
-#include <trace/events/sched.h>
-
 /*
  * Approximate:
  *   val * y^n,    where y^32 ~= 0.5 (~1 scheduling period)
@@ -83,8 +77,6 @@ static u32 __accumulate_pelt_segments(u64 periods, u32 d1, u32 d3)
 	return c1 + c2 + c3;
 }
 
-#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
-
 /*
  * Accumulate the three separate parts of the sum; d1 the remainder
  * of the last (incomplete) period, d2 the span of full periods and d3
@@ -121,8 +113,8 @@ accumulate_sum(u64 delta, struct sched_avg *sa,
 	 */
 	if (periods) {
 		sa->load_sum = decay_load(sa->load_sum, periods);
-		sa->runnable_load_sum =
-			decay_load(sa->runnable_load_sum, periods);
+		sa->runnable_sum =
+			decay_load(sa->runnable_sum, periods);
 		sa->util_sum = decay_load((u64)(sa->util_sum), periods);
 
 		/*
@@ -137,7 +129,7 @@ accumulate_sum(u64 delta, struct sched_avg *sa,
 			 *	runnable = running = 0;
 			 *
 			 * clause from ___update_load_sum(); this results in
-			 * the below usage of @contrib to dissapear entirely,
+			 * the below usage of @contrib to disappear entirely,
 			 * so no point in calculating it.
 			 */
 			contrib = __accumulate_pelt_segments(periods,
@@ -149,7 +141,7 @@ accumulate_sum(u64 delta, struct sched_avg *sa,
 	if (load)
 		sa->load_sum += load * contrib;
 	if (runnable)
-		sa->runnable_load_sum += runnable * contrib;
+		sa->runnable_sum += runnable * contrib << SCHED_CAPACITY_SHIFT;
 	if (running)
 		sa->util_sum += contrib << SCHED_CAPACITY_SHIFT;
 
@@ -237,16 +229,40 @@ ___update_load_sum(u64 now, struct sched_avg *sa,
 	return 1;
 }
 
+/*
+ * When syncing *_avg with *_sum, we must take into account the current
+ * position in the PELT segment otherwise the remaining part of the segment
+ * will be considered as idle time whereas it's not yet elapsed and this will
+ * generate unwanted oscillation in the range [1002..1024[.
+ *
+ * The max value of *_sum varies with the position in the time segment and is
+ * equals to :
+ *
+ *   LOAD_AVG_MAX*y + sa->period_contrib
+ *
+ * which can be simplified into:
+ *
+ *   LOAD_AVG_MAX - 1024 + sa->period_contrib
+ *
+ * because LOAD_AVG_MAX*y == LOAD_AVG_MAX-1024
+ *
+ * The same care must be taken when a sched entity is added, updated or
+ * removed from a cfs_rq and we need to update sched_avg. Scheduler entities
+ * and the cfs rq, to which they are attached, have the same position in the
+ * time segment because they use the same clock. This means that we can use
+ * the period_contrib of cfs_rq when updating the sched_avg of a sched_entity
+ * if it's more convenient.
+ */
 static __always_inline void
-___update_load_avg(struct sched_avg *sa, unsigned long load, unsigned long runnable)
+___update_load_avg(struct sched_avg *sa, unsigned long load)
 {
-	u32 divider = LOAD_AVG_MAX - 1024 + sa->period_contrib;
+	u32 divider = get_pelt_divider(sa);
 
 	/*
 	 * Step 2: update *_avg.
 	 */
 	sa->load_avg = div_u64(load * sa->load_sum, divider);
-	sa->runnable_load_avg =	div_u64(runnable * sa->runnable_load_sum, divider);
+	sa->runnable_avg = div_u64(sa->runnable_sum, divider);
 	WRITE_ONCE(sa->util_avg, sa->util_sum / divider);
 }
 
@@ -254,33 +270,32 @@ ___update_load_avg(struct sched_avg *sa, unsigned long load, unsigned long runna
  * sched_entity:
  *
  *   task:
- *     se_runnable() == se_weight()
+ *     se_weight()   = se->load.weight
+ *     se_runnable() = !!on_rq
  *
  *   group: [ see update_cfs_group() ]
  *     se_weight()   = tg->weight * grq->load_avg / tg->load_avg
- *     se_runnable() = se_weight(se) * grq->runnable_load_avg / grq->load_avg
- *
- *   load_sum := runnable_sum
- *   load_avg = se_weight(se) * runnable_avg
+ *     se_runnable() = grq->h_nr_running
  *
- *   runnable_load_sum := runnable_sum
- *   runnable_load_avg = se_runnable(se) * runnable_avg
+ *   runnable_sum = se_runnable() * runnable = grq->runnable_sum
+ *   runnable_avg = runnable_sum
  *
- * XXX collapse load_sum and runnable_load_sum
+ *   load_sum := runnable
+ *   load_avg = se_weight(se) * load_sum
  *
  * cfq_rq:
  *
+ *   runnable_sum = \Sum se->avg.runnable_sum
+ *   runnable_avg = \Sum se->avg.runnable_avg
+ *
  *   load_sum = \Sum se_weight(se) * se->avg.load_sum
  *   load_avg = \Sum se->avg.load_avg
- *
- *   runnable_load_sum = \Sum se_runnable(se) * se->avg.runnable_load_sum
- *   runnable_load_avg = \Sum se->avg.runable_load_avg
  */
 
 int __update_load_avg_blocked_se(u64 now, struct sched_entity *se)
 {
 	if (___update_load_sum(now, &se->avg, 0, 0, 0)) {
-		___update_load_avg(&se->avg, se_weight(se), se_runnable(se));
+		___update_load_avg(&se->avg, se_weight(se));
 		trace_pelt_se_tp(se);
 		return 1;
 	}
@@ -290,10 +305,10 @@ int __update_load_avg_blocked_se(u64 now, struct sched_entity *se)
 
 int __update_load_avg_se(u64 now, struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-	if (___update_load_sum(now, &se->avg, !!se->on_rq, !!se->on_rq,
+	if (___update_load_sum(now, &se->avg, !!se->on_rq, se_runnable(se),
 				cfs_rq->curr == se)) {
 
-		___update_load_avg(&se->avg, se_weight(se), se_runnable(se));
+		___update_load_avg(&se->avg, se_weight(se));
 		cfs_se_util_change(&se->avg);
 		trace_pelt_se_tp(se);
 		return 1;
@@ -306,10 +321,10 @@ int __update_load_avg_cfs_rq(u64 now, struct cfs_rq *cfs_rq)
 {
 	if (___update_load_sum(now, &cfs_rq->avg,
 				scale_load_down(cfs_rq->load.weight),
-				scale_load_down(cfs_rq->runnable_weight),
+				cfs_rq->h_nr_running,
 				cfs_rq->curr != NULL)) {
 
-		___update_load_avg(&cfs_rq->avg, 1, 1);
+		___update_load_avg(&cfs_rq->avg, 1);
 		trace_pelt_cfs_tp(cfs_rq);
 		return 1;
 	}
@@ -322,9 +337,9 @@ int __update_load_avg_cfs_rq(u64 now, struct cfs_rq *cfs_rq)
  *
  *   util_sum = \Sum se->avg.util_sum but se->avg.util_sum is not tracked
  *   util_sum = cpu_scale * load_sum
- *   runnable_load_sum = load_sum
+ *   runnable_sum = util_sum
  *
- *   load_avg and runnable_load_avg are not supported and meaningless.
+ *   load_avg and runnable_avg are not supported and meaningless.
  *
  */
 
@@ -335,7 +350,7 @@ int update_rt_rq_load_avg(u64 now, struct rq *rq, int running)
 				running,
 				running)) {
 
-		___update_load_avg(&rq->avg_rt, 1, 1);
+		___update_load_avg(&rq->avg_rt, 1);
 		trace_pelt_rt_tp(rq);
 		return 1;
 	}
@@ -348,7 +363,9 @@ int update_rt_rq_load_avg(u64 now, struct rq *rq, int running)
  *
  *   util_sum = \Sum se->avg.util_sum but se->avg.util_sum is not tracked
  *   util_sum = cpu_scale * load_sum
- *   runnable_load_sum = load_sum
+ *   runnable_sum = util_sum
+ *
+ *   load_avg and runnable_avg are not supported and meaningless.
  *
  */
 
@@ -359,7 +376,7 @@ int update_dl_rq_load_avg(u64 now, struct rq *rq, int running)
 				running,
 				running)) {
 
-		___update_load_avg(&rq->avg_dl, 1, 1);
+		___update_load_avg(&rq->avg_dl, 1);
 		trace_pelt_dl_tp(rq);
 		return 1;
 	}
@@ -367,13 +384,46 @@ int update_dl_rq_load_avg(u64 now, struct rq *rq, int running)
 	return 0;
 }
 
+#ifdef CONFIG_SCHED_THERMAL_PRESSURE
+/*
+ * thermal:
+ *
+ *   load_sum = \Sum se->avg.load_sum but se->avg.load_sum is not tracked
+ *
+ *   util_avg and runnable_load_avg are not supported and meaningless.
+ *
+ * Unlike rt/dl utilization tracking that track time spent by a cpu
+ * running a rt/dl task through util_avg, the average thermal pressure is
+ * tracked through load_avg. This is because thermal pressure signal is
+ * time weighted "delta" capacity unlike util_avg which is binary.
+ * "delta capacity" =  actual capacity  -
+ *			capped capacity a cpu due to a thermal event.
+ */
+
+int update_thermal_load_avg(u64 now, struct rq *rq, u64 capacity)
+{
+	if (___update_load_sum(now, &rq->avg_thermal,
+			       capacity,
+			       capacity,
+			       capacity)) {
+		___update_load_avg(&rq->avg_thermal, 1);
+		trace_pelt_thermal_tp(rq);
+		return 1;
+	}
+
+	return 0;
+}
+#endif
+
 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
 /*
  * irq:
  *
  *   util_sum = \Sum se->avg.util_sum but se->avg.util_sum is not tracked
  *   util_sum = cpu_scale * load_sum
- *   runnable_load_sum = load_sum
+ *   runnable_sum = util_sum
+ *
+ *   load_avg and runnable_avg are not supported and meaningless.
  *
  */
 
@@ -410,7 +460,7 @@ int update_irq_load_avg(struct rq *rq, u64 running)
 				1);
 
 	if (ret) {
-		___update_load_avg(&rq->avg_irq, 1, 1);
+		___update_load_avg(&rq->avg_irq, 1);
 		trace_pelt_irq_tp(rq);
 	}