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From: Yuyang Du <yuyang.du@intel.com>
To: mingo@kernel.org, peterz@infradead.org, linux-kernel@vger.kernel.org
Cc: pjt@google.com, bsegall@google.com, morten.rasmussen@arm.com,
	vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
	Yuyang Du <yuyang.du@intel.com>
Subject: [PATCH 2/4] sched/fair: Remove SCHED_LOAD_SHIFT and SCHED_LOAD_SCALE
Date: Mon,  5 Oct 2015 01:56:57 +0800	[thread overview]
Message-ID: <1443981419-16665-3-git-send-email-yuyang.du@intel.com> (raw)
In-Reply-To: <1443981419-16665-1-git-send-email-yuyang.du@intel.com>

After cleaning up the sched metrics, these two definitions that cause
ambiguity are not needed any more. Use NICE_0_LOAD_SHIFT and NICE_0_LOAD
instead (the names suggest clearly who they are).

Suggested-by: Ben Segall <bsegall@google.com>
Signed-off-by: Yuyang Du <yuyang.du@intel.com>
---
 kernel/sched/fair.c  |  4 ++--
 kernel/sched/sched.h | 22 +++++++++++-----------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index c61fd8e..fdb7937 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -682,7 +682,7 @@ void init_entity_runnable_average(struct sched_entity *se)
 	sa->period_contrib = 1023;
 	sa->load_avg = scale_load_down(se->load.weight);
 	sa->load_sum = sa->load_avg * LOAD_AVG_MAX;
-	sa->util_avg = scale_load_down(SCHED_LOAD_SCALE);
+	sa->util_avg = SCHED_CAPACITY_SCALE;
 	sa->util_sum = sa->util_avg * LOAD_AVG_MAX;
 	/* when this task enqueue'ed, it will contribute to its cfs_rq's load_avg */
 }
@@ -6651,7 +6651,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
 	if (busiest->group_type == group_overloaded &&
 	    local->group_type   == group_overloaded) {
 		load_above_capacity = busiest->sum_nr_running *
-					SCHED_LOAD_SCALE;
+					SCHED_CAPACITY_SCALE;
 		if (load_above_capacity > busiest->group_capacity)
 			load_above_capacity -= busiest->group_capacity;
 		else
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 31b4022..3d03956 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -53,25 +53,25 @@ static inline void update_cpu_load_active(struct rq *this_rq) { }
  * increased costs.
  */
 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load  */
-# define SCHED_LOAD_SHIFT	(SCHED_RESOLUTION_SHIFT + SCHED_RESOLUTION_SHIFT)
+# define NICE_0_LOAD_SHIFT	(SCHED_RESOLUTION_SHIFT + SCHED_RESOLUTION_SHIFT)
 # define scale_load(w)		((w) << SCHED_RESOLUTION_SHIFT)
 # define scale_load_down(w)	((w) >> SCHED_RESOLUTION_SHIFT)
 #else
-# define SCHED_LOAD_SHIFT	(SCHED_RESOLUTION_SHIFT)
+# define NICE_0_LOAD_SHIFT	(SCHED_RESOLUTION_SHIFT)
 # define scale_load(w)		(w)
 # define scale_load_down(w)	(w)
 #endif
 
-#define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
-
 /*
- * NICE_0's weight (visible to user) and its load (invisible to user) have
- * independent resolution, but they should be well calibrated. We use scale_load()
- * and scale_load_down(w) to convert between them, the following must be true:
- * scale_load(prio_to_weight[20]) == NICE_0_LOAD
+ * Task weight (visible to user) and its load (invisible to user) have
+ * independent resolution, but they should be well calibrated. We use
+ * scale_load() and scale_load_down(w) to convert between them. The
+ * following must be true:
+ *
+ *  scale_load(prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
+ *
  */
-#define NICE_0_LOAD		SCHED_LOAD_SCALE
-#define NICE_0_SHIFT		SCHED_LOAD_SHIFT
+#define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
 
 /*
  * Single value that decides SCHED_DEADLINE internal math precision.
@@ -850,7 +850,7 @@ DECLARE_PER_CPU(struct sched_domain *, sd_asym);
 struct sched_group_capacity {
 	atomic_t ref;
 	/*
-	 * CPU capacity of this group, SCHED_LOAD_SCALE being max capacity
+	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
 	 * for a single CPU.
 	 */
 	unsigned int capacity;
-- 
2.1.4


  parent reply	other threads:[~2015-10-05  1:46 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-10-04 17:56 [PATCH 0/4] sched/fair: Clean up sched metric definitions Yuyang Du
2015-10-04 17:56 ` [PATCH 1/4] sched/fair: Generalize the load/util averages resolution definition Yuyang Du
2015-10-05  7:04   ` Ingo Molnar
2015-10-06  8:00     ` Yuyang Du
2015-10-09 23:04       ` Yuyang Du
2015-10-05 10:52   ` Peter Zijlstra
2015-10-04 17:56 ` Yuyang Du [this message]
2015-10-06  9:29   ` [PATCH 2/4] sched/fair: Remove SCHED_LOAD_SHIFT and SCHED_LOAD_SCALE Vincent Guittot
2015-10-04 17:56 ` [PATCH 3/4] sched/fair: Remove scale_load_down() for load_avg Yuyang Du
2015-10-04 17:56 ` [PATCH 4/4] sched/fair: Rename scale_load() and scale_load_down() Yuyang Du

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