[PATCH 14/16] sched: Remove check that skips small VMAs

Mel Gorman
2013-07-11T09:47:23Z

task_numa_work skips small VMAs. At the time the logic was to reduce the
scanning overhead which was considerable. It is a dubious hack at best.
It would make much more sense to cache where faults have been observed
and only rescan those regions during subsequent PTE scans. Remove this
hack as motivation to do it properly in the future.

Signed-off-by: Mel Gorman <mgorman@suse.de>
---
kernel/sched/fair.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 3ffe097..45dcf51 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1080,10 +1080,6 @@ void task_numa_work(struct callback_head *work)
if (!vma_migratable(vma))
continue;

- /* Skip small VMAs. They are not likely to be of relevance */
- if (vma->vm_end - vma->vm_start < HPAGE_SIZE)
- continue;
-
do {
start = max(start, vma->vm_start);
end = ALIGN(start + (pages << PAGE_SHIFT), HPAGE_SIZE);
--
1.8.1.4