[RFC PATCH 02/10] mm/compaction: skip useless pfn for scanner's cached pfn

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Scanner's cached pfn is used to determine the start position of scanner
at next compaction run. Current cached pfn points the skipped pageblock
so we uselessly checks whether pageblock is valid for compaction and
skip-bit is set or not. If we set scanner's cached pfn to next pfn of
skipped pageblock, we don't need to do this check.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
---
 mm/compaction.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/mm/compaction.c b/mm/compaction.c
index 4397bf7..9c5d43c 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -265,7 +265,6 @@ static void update_pageblock_skip(struct compact_control *cc,
 			unsigned long curr_pfn, bool migrate_scanner)
 {
 	struct zone *zone = cc->zone;
-	unsigned long pfn;
 
 	if (cc->ignore_skip_hint)
 		return;
@@ -285,18 +284,16 @@ static void update_pageblock_skip(struct compact_control *cc,
 
 	set_pageblock_skip(page);
 
-	pfn = page_to_pfn(page);
-
 	/* Update where async and sync compaction should restart */
 	if (migrate_scanner) {
-		if (pfn > zone->compact_cached_migrate_pfn[0])
-			zone->compact_cached_migrate_pfn[0] = pfn;
+		if (end_pfn > zone->compact_cached_migrate_pfn[0])
+			zone->compact_cached_migrate_pfn[0] = end_pfn;
 		if (cc->mode != MIGRATE_ASYNC &&
-		    pfn > zone->compact_cached_migrate_pfn[1])
-			zone->compact_cached_migrate_pfn[1] = pfn;
+		    end_pfn > zone->compact_cached_migrate_pfn[1])
+			zone->compact_cached_migrate_pfn[1] = end_pfn;
 	} else {
-		if (pfn < zone->compact_cached_free_pfn)
-			zone->compact_cached_free_pfn = pfn;
+		if (start_pfn < zone->compact_cached_free_pfn)
+			zone->compact_cached_free_pfn = start_pfn;
 	}
 }
 #else
-- 
1.9.1

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]