linux-kernel - [RFC][Patch 08/18] sched: update find_idlest

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Message-Id: <1303332697-16426-9-git-send-email-ncrao@google.com>
Date:	Wed, 20 Apr 2011 13:51:27 -0700
From:	Nikhil Rao <ncrao@...gle.com>
To:	Ingo Molnar <mingo@...e.hu>, Peter Zijlstra <peterz@...radead.org>
Cc:	Paul Turner <pjt@...gle.com>, Mike Galbraith <efault@....de>,
	linux-kernel@...r.kernel.org, Nikhil Rao <ncrao@...gle.com>
Subject: [RFC][Patch 08/18] sched: update find_idlest_group() to use u64

Update find_idlest_group() to use u64 to accumulate and maintain cpu_load
weights.

Signed-off-by: Nikhil Rao <ncrao@...gle.com>
---
 kernel/sched_fair.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 0b36548..029dd4f 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1527,11 +1527,11 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
 		  int this_cpu, int load_idx)
 {
 	struct sched_group *idlest = NULL, *group = sd->groups;
-	unsigned long min_load = ULONG_MAX, this_load = 0;
+	u64 min_load = ULLONG_MAX, this_load = 0;
 	int imbalance = 100 + (sd->imbalance_pct-100)/2;
 
 	do {
-		unsigned long load, avg_load;
+		u64 load, avg_load;
 		int local_group;
 		int i;
 
@@ -1557,7 +1557,8 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
 		}
 
 		/* Adjust by relative CPU power of the group */
-		avg_load = (avg_load * SCHED_POWER_SCALE) / group->cpu_power;
+		avg_load *= SCHED_POWER_SCALE;
+		avg_load = div_u64(avg_load, group->cpu_power);
 
 		if (local_group) {
 			this_load = avg_load;
-- 
1.7.3.1

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