mm, compaction: rename COMPACT_PARTIAL to COMPACT_SUCCESS

COMPACT_PARTIAL has historically meant that compaction returned after
doing some work without fully compacting a zone.  It however didn't
distinguish if compaction terminated because it succeeded in creating
the requested high-order page.  This has changed recently and now we
only return COMPACT_PARTIAL when compaction thinks it succeeded, or the
high-order watermark check in compaction_suitable() passes and no
compaction needs to be done.

So at this point we can make the return value clearer by renaming it to
COMPACT_SUCCESS.  The next patch will remove some redundant tests for
success where compaction just returned COMPACT_SUCCESS.

Link: http://lkml.kernel.org/r/20160810091226.6709-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/include/linux/compaction.h b/include/linux/compaction.h
index 1bb58581301c..e88c037afe47 100644
--- a/include/linux/compaction.h
+++ b/include/linux/compaction.h
@@ -49,10 +49,10 @@ enum compact_result {
 	COMPACT_CONTENDED,
 
 	/*
-	 * direct compaction partially compacted a zone and there might be
-	 * suitable pages
+	 * direct compaction terminated after concluding that the allocation
+	 * should now succeed
 	 */
-	COMPACT_PARTIAL,
+	COMPACT_SUCCESS,
 };
 
 struct alloc_context; /* in mm/internal.h */
@@ -88,7 +88,7 @@ static inline bool compaction_made_progress(enum compact_result result)
 	 * that the compaction successfully isolated and migrated some
 	 * pageblocks.
 	 */
-	if (result == COMPACT_PARTIAL)
+	if (result == COMPACT_SUCCESS)
 		return true;
 
 	return false;