aboutsummaryrefslogtreecommitdiffstats
path: root/mm
diff options
context:
space:
mode:
authorJoonsoo Kim <iamjoonsoo.kim@lge.com>2014-11-13 15:19:07 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-11-13 16:17:05 -0800
commit58420016303769f74c58248a59ca0f435041b352 (patch)
tree2c098ccf82bf853d78cb0ffb126b42b43f825a6e /mm
parentzram: avoid kunmap_atomic() of a NULL pointer (diff)
downloadlinux-dev-58420016303769f74c58248a59ca0f435041b352.tar.xz
linux-dev-58420016303769f74c58248a59ca0f435041b352.zip
mm/compaction: skip the range until proper target pageblock is met
Commit 7d49d8868336 ("mm, compaction: reduce zone checking frequency in the migration scanner") has a side-effect that changes the iteration range calculation. Before the change, block_end_pfn is calculated using start_pfn, but now it blindly adds pageblock_nr_pages to the previous value. This causes the problem that isolation_start_pfn is larger than block_end_pfn when we isolate the page with more than pageblock order. In this case, isolation would fail due to an invalid range parameter. To prevent this, this patch implements skipping the range until a proper target pageblock is met. Without this patch, CMA with more than pageblock order always fails but with this patch it will succeed. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/compaction.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/mm/compaction.c b/mm/compaction.c
index ec74cf0123ef..4f0151cfd238 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -479,6 +479,16 @@ isolate_freepages_range(struct compact_control *cc,
block_end_pfn = min(block_end_pfn, end_pfn);
+ /*
+ * pfn could pass the block_end_pfn if isolated freepage
+ * is more than pageblock order. In this case, we adjust
+ * scanning range to right one.
+ */
+ if (pfn >= block_end_pfn) {
+ block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
+ block_end_pfn = min(block_end_pfn, end_pfn);
+ }
+
if (!pageblock_pfn_to_page(pfn, block_end_pfn, cc->zone))
break;