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authorSuresh Siddha <suresh.b.siddha@intel.com>2007-09-05 14:32:48 +0200
committerIngo Molnar <mingo@elte.hu>2007-09-05 14:32:48 +0200
commit7fd0d2dde929ead79901e389e70dbfb3c6c06986 (patch)
tree577c4626e1e6f1de79e41deaeea6699261c873aa /kernel
parentb21010ed6498391c0f359f2a89c907533fe07fec (diff)
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sched: fix MC/HT scheduler optimization, without breaking the FUZZ logic.
First fix the check if (*imbalance + SCHED_LOAD_SCALE_FUZZ < busiest_load_per_task) with this if (*imbalance < busiest_load_per_task) As the current check is always false for nice 0 tasks (as SCHED_LOAD_SCALE_FUZZ is same as busiest_load_per_task for nice 0 tasks). With the above change, imbalance was getting reset to 0 in the corner case condition, making the FUZZ logic fail. Fix it by not corrupting the imbalance and change the imbalance, only when it finds that the HT/MC optimization is needed. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sched.c8
1 files changed, 3 insertions, 5 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index b533d6db78aa..c8759ec6d8a9 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2512,7 +2512,7 @@ group_next:
* a think about bumping its value to force at least one task to be
* moved
*/
- if (*imbalance + SCHED_LOAD_SCALE_FUZZ < busiest_load_per_task) {
+ if (*imbalance < busiest_load_per_task) {
unsigned long tmp, pwr_now, pwr_move;
unsigned int imbn;
@@ -2564,10 +2564,8 @@ small_imbalance:
pwr_move /= SCHED_LOAD_SCALE;
/* Move if we gain throughput */
- if (pwr_move <= pwr_now)
- goto out_balanced;
-
- *imbalance = busiest_load_per_task;
+ if (pwr_move > pwr_now)
+ *imbalance = busiest_load_per_task;
}
return busiest;