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>
This commit is contained in:
Vlastimil Babka 2016-10-07 16:57:41 -07:00 committed by Linus Torvalds
parent 791cae9620
commit cf378319d3
4 changed files with 12 additions and 12 deletions

View File

@ -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;

View File

@ -13,7 +13,7 @@
EM( COMPACT_SKIPPED, "skipped") \
EM( COMPACT_DEFERRED, "deferred") \
EM( COMPACT_CONTINUE, "continue") \
EM( COMPACT_PARTIAL, "partial") \
EM( COMPACT_SUCCESS, "success") \
EM( COMPACT_PARTIAL_SKIPPED, "partial_skipped") \
EM( COMPACT_COMPLETE, "complete") \
EM( COMPACT_NO_SUITABLE_PAGE, "no_suitable_page") \

View File

@ -1329,13 +1329,13 @@ static enum compact_result __compact_finished(struct zone *zone, struct compact_
/* Job done if page is free of the right migratetype */
if (!list_empty(&area->free_list[migratetype]))
return COMPACT_PARTIAL;
return COMPACT_SUCCESS;
#ifdef CONFIG_CMA
/* MIGRATE_MOVABLE can fallback on MIGRATE_CMA */
if (migratetype == MIGRATE_MOVABLE &&
!list_empty(&area->free_list[MIGRATE_CMA]))
return COMPACT_PARTIAL;
return COMPACT_SUCCESS;
#endif
/*
* Job done if allocation would steal freepages from
@ -1343,7 +1343,7 @@ static enum compact_result __compact_finished(struct zone *zone, struct compact_
*/
if (find_suitable_fallback(area, order, migratetype,
true, &can_steal) != -1)
return COMPACT_PARTIAL;
return COMPACT_SUCCESS;
}
return COMPACT_NO_SUITABLE_PAGE;
@ -1367,7 +1367,7 @@ static enum compact_result compact_finished(struct zone *zone,
* compaction_suitable: Is this suitable to run compaction on this zone now?
* Returns
* COMPACT_SKIPPED - If there are too few free pages for compaction
* COMPACT_PARTIAL - If the allocation would succeed without compaction
* COMPACT_SUCCESS - If the allocation would succeed without compaction
* COMPACT_CONTINUE - If compaction should run now
*/
static enum compact_result __compaction_suitable(struct zone *zone, int order,
@ -1388,7 +1388,7 @@ static enum compact_result __compaction_suitable(struct zone *zone, int order,
*/
if (zone_watermark_ok(zone, order, watermark, classzone_idx,
alloc_flags))
return COMPACT_PARTIAL;
return COMPACT_SUCCESS;
/*
* Watermarks for order-0 must be met for compaction. Note the 2UL.
@ -1477,7 +1477,7 @@ static enum compact_result compact_zone(struct zone *zone, struct compact_contro
ret = compaction_suitable(zone, cc->order, cc->alloc_flags,
cc->classzone_idx);
/* Compaction is likely to fail */
if (ret == COMPACT_PARTIAL || ret == COMPACT_SKIPPED)
if (ret == COMPACT_SUCCESS || ret == COMPACT_SKIPPED)
return ret;
/* huh, compaction_suitable is returning something unexpected */

View File

@ -2495,7 +2495,7 @@ static inline bool should_continue_reclaim(struct pglist_data *pgdat,
continue;
switch (compaction_suitable(zone, sc->order, 0, sc->reclaim_idx)) {
case COMPACT_PARTIAL:
case COMPACT_SUCCESS:
case COMPACT_CONTINUE:
return false;
default: