From 79e976fdfc7b519aaf27501c5bfa7fa976d2cc2d Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Thu, 24 Aug 2017 17:45:35 +0200
Subject: [PATCH] sched/fair: Introduce {en,de}queue_load_avg()
References: bnc#1066110 Scheduler utilisation tracking
Patch-mainline: v4.15-rc1
Git-commit: 8d5b9025f9b4500f828260dc62e8ffa823ce0d59
Analogous to the existing {en,de}queue_runnable_load_avg() add helpers
for {en,de}queue_load_avg(). More users will follow.
Includes some code movement to avoid fwd declarations.
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: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
kernel/sched/fair.c | 156 +++++++++++++++++++++++++++++-----------------------
1 file changed, 86 insertions(+), 70 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 0d678b18a3a9..fbd651918cc4 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2705,6 +2705,90 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
cfs_rq->nr_running--;
}
+/*
+ * Signed add and clamp on underflow.
+ *
+ * Explicitly do a load-store to ensure the intermediate value never hits
+ * memory. This allows lockless observations without ever seeing the negative
+ * values.
+ */
+#define add_positive(_ptr, _val) do { \
+ typeof(_ptr) ptr = (_ptr); \
+ typeof(_val) val = (_val); \
+ typeof(*ptr) res, var = READ_ONCE(*ptr); \
+ \
+ res = var + val; \
+ \
+ if (val < 0 && res > var) \
+ res = 0; \
+ \
+ WRITE_ONCE(*ptr, res); \
+} while (0)
+
+/*
+ * Unsigned subtract and clamp on underflow.
+ *
+ * Explicitly do a load-store to ensure the intermediate value never hits
+ * memory. This allows lockless observations without ever seeing the negative
+ * values.
+ */
+#define sub_positive(_ptr, _val) do { \
+ typeof(_ptr) ptr = (_ptr); \
+ typeof(*ptr) val = (_val); \
+ typeof(*ptr) res, var = READ_ONCE(*ptr); \
+ res = var - val; \
+ if (res > var) \
+ res = 0; \
+ WRITE_ONCE(*ptr, res); \
+} while (0)
+
+#ifdef CONFIG_SMP
+/*
+ * XXX we want to get rid of this helper and use the full load resolution.
+ */
+static inline long se_weight(struct sched_entity *se)
+{
+ return scale_load_down(se->load.weight);
+}
+
+static inline void
+enqueue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+ cfs_rq->runnable_load_avg += se->avg.load_avg;
+ cfs_rq->runnable_load_sum += se_weight(se) * se->avg.load_sum;
+}
+
+static inline void
+dequeue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+ sub_positive(&cfs_rq->runnable_load_avg, se->avg.load_avg);
+ sub_positive(&cfs_rq->runnable_load_sum, se_weight(se) * se->avg.load_sum);
+}
+
+static inline void
+enqueue_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+ cfs_rq->avg.load_avg += se->avg.load_avg;
+ cfs_rq->avg.load_sum += se_weight(se) * se->avg.load_sum;
+}
+
+static inline void
+dequeue_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+ sub_positive(&cfs_rq->avg.load_avg, se->avg.load_avg);
+ sub_positive(&cfs_rq->avg.load_sum, se_weight(se) * se->avg.load_sum);
+}
+#else
+static inline void
+enqueue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { }
+static inline void
+dequeue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { }
+static inline void
+enqueue_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { }
+static inline void
+dequeue_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { }
+#endif
+
#ifdef CONFIG_FAIR_GROUP_SCHED
# ifdef CONFIG_SMP
/*
@@ -3083,14 +3167,6 @@ ___update_load_avg(struct sched_avg *sa, unsigned long weight, struct cfs_rq *cf
sa->util_avg = sa->util_sum / divider;
}
-/*
- * XXX we want to get rid of this helper and use the full load resolution.
- */
-static inline long se_weight(struct sched_entity *se)
-{
- return scale_load_down(se->load.weight);
-}
-
/*
* sched_entity:
*
@@ -3140,26 +3216,6 @@ __update_load_avg_cfs_rq(u64 now, int cpu, struct cfs_rq *cfs_rq)
return 0;
}
-/*
- * Signed add and clamp on underflow.
- *
- * Explicitly do a load-store to ensure the intermediate value never hits
- * memory. This allows lockless observations without ever seeing the negative
- * values.
- */
-#define add_positive(_ptr, _val) do { \
- typeof(_ptr) ptr = (_ptr); \
- typeof(_val) val = (_val); \
- typeof(*ptr) res, var = READ_ONCE(*ptr); \
- \
- res = var + val; \
- \
- if (val < 0 && res > var) \
- res = 0; \
- \
- WRITE_ONCE(*ptr, res); \
-} while (0)
-
#ifdef CONFIG_FAIR_GROUP_SCHED
/**
* update_tg_load_avg - update the tg's load avg
@@ -3404,23 +3460,6 @@ static inline void set_tg_cfs_propagate(struct cfs_rq *cfs_rq) {}
#endif /* CONFIG_FAIR_GROUP_SCHED */
-/*
- * Unsigned subtract and clamp on underflow.
- *
- * Explicitly do a load-store to ensure the intermediate value never hits
- * memory. This allows lockless observations without ever seeing the negative
- * values.
- */
-#define sub_positive(_ptr, _val) do { \
- typeof(_ptr) ptr = (_ptr); \
- typeof(*ptr) val = (_val); \
- typeof(*ptr) res, var = READ_ONCE(*ptr); \
- res = var - val; \
- if (res > var) \
- res = 0; \
- WRITE_ONCE(*ptr, res); \
-} while (0)
-
/**
* update_cfs_rq_load_avg - update the cfs_rq's load/util averages
* @now: current time, as per cfs_rq_clock_task()
@@ -3489,8 +3528,7 @@ update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
se->avg.last_update_time = cfs_rq->avg.last_update_time;
- cfs_rq->avg.load_avg += se->avg.load_avg;
- cfs_rq->avg.load_sum += se_weight(se) * se->avg.load_sum;
+ enqueue_load_avg(cfs_rq, se);
cfs_rq->avg.util_avg += se->avg.util_avg;
cfs_rq->avg.util_sum += se->avg.util_sum;
set_tg_cfs_propagate(cfs_rq);
@@ -3508,9 +3546,7 @@ static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s
*/
static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
-
- sub_positive(&cfs_rq->avg.load_avg, se->avg.load_avg);
- sub_positive(&cfs_rq->avg.load_sum, se_weight(se) * se->avg.load_sum);
+ dequeue_load_avg(cfs_rq, se);
sub_positive(&cfs_rq->avg.util_avg, se->avg.util_avg);
sub_positive(&cfs_rq->avg.util_sum, se->avg.util_sum);
set_tg_cfs_propagate(cfs_rq);
@@ -3552,22 +3588,6 @@ static inline void update_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s
update_tg_load_avg(cfs_rq, 0);
}
-/* Add the load generated by se into cfs_rq's load average */
-static inline void
-enqueue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
- cfs_rq->runnable_load_avg += se->avg.load_avg;
- cfs_rq->runnable_load_sum += se_weight(se) * se->avg.load_sum;
-}
-
-/* Remove the runnable load generated by se from cfs_rq's runnable load average */
-static inline void
-dequeue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
- sub_positive(&cfs_rq->runnable_load_avg, se->avg.load_avg);
- sub_positive(&cfs_rq->runnable_load_sum, se_weight(se) * se->avg.load_sum);
-}
-
#ifndef CONFIG_64BIT
static inline u64 cfs_rq_last_update_time(struct cfs_rq *cfs_rq)
{
@@ -3654,10 +3674,6 @@ static inline void update_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s
cfs_rq_util_change(cfs_rq);
}
-static inline void
-enqueue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) {}
-static inline void
-dequeue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) {}
static inline void remove_entity_load_avg(struct sched_entity *se) {}
static inline void