summaryrefslogtreecommitdiffstats
path: root/mm/compaction.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/compaction.c')
-rw-r--r--mm/compaction.c84
1 files changed, 40 insertions, 44 deletions
diff --git a/mm/compaction.c b/mm/compaction.c
index b6ab7716006..37f97628706 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -217,21 +217,12 @@ static inline bool compact_trylock_irqsave(spinlock_t *lock,
/* Returns true if the page is within a block suitable for migration to */
static bool suitable_migration_target(struct page *page)
{
- int migratetype = get_pageblock_migratetype(page);
-
- /* Don't interfere with memory hot-remove or the min_free_kbytes blocks */
- if (migratetype == MIGRATE_RESERVE)
- return false;
-
- if (is_migrate_isolate(migratetype))
- return false;
-
- /* If the page is a large free page, then allow migration */
+ /* If the page is a large free page, then disallow migration */
if (PageBuddy(page) && page_order(page) >= pageblock_order)
- return true;
+ return false;
/* If the block is MIGRATE_MOVABLE or MIGRATE_CMA, allow migration */
- if (migrate_async_suitable(migratetype))
+ if (migrate_async_suitable(get_pageblock_migratetype(page)))
return true;
/* Otherwise skip the block */
@@ -253,6 +244,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
struct page *cursor, *valid_page = NULL;
unsigned long flags;
bool locked = false;
+ bool checked_pageblock = false;
cursor = pfn_to_page(blockpfn);
@@ -284,8 +276,16 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
break;
/* Recheck this is a suitable migration target under lock */
- if (!strict && !suitable_migration_target(page))
- break;
+ if (!strict && !checked_pageblock) {
+ /*
+ * We need to check suitability of pageblock only once
+ * and this isolate_freepages_block() is called with
+ * pageblock range, so just check once is sufficient.
+ */
+ checked_pageblock = true;
+ if (!suitable_migration_target(page))
+ break;
+ }
/* Recheck this is a buddy page under lock */
if (!PageBuddy(page))
@@ -460,12 +460,13 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
unsigned long last_pageblock_nr = 0, pageblock_nr;
unsigned long nr_scanned = 0, nr_isolated = 0;
struct list_head *migratelist = &cc->migratepages;
- isolate_mode_t mode = 0;
struct lruvec *lruvec;
unsigned long flags;
bool locked = false;
struct page *page = NULL, *valid_page = NULL;
bool skipped_async_unsuitable = false;
+ const isolate_mode_t mode = (!cc->sync ? ISOLATE_ASYNC_MIGRATE : 0) |
+ (unevictable ? ISOLATE_UNEVICTABLE : 0);
/*
* Ensure that there are not too many pages isolated from the LRU
@@ -487,7 +488,7 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
cond_resched();
for (; low_pfn < end_pfn; low_pfn++) {
/* give a chance to irqs before checking need_resched() */
- if (locked && !((low_pfn+1) % SWAP_CLUSTER_MAX)) {
+ if (locked && !(low_pfn % SWAP_CLUSTER_MAX)) {
if (should_release_lock(&zone->lru_lock)) {
spin_unlock_irqrestore(&zone->lru_lock, flags);
locked = false;
@@ -526,8 +527,25 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
/* If isolation recently failed, do not retry */
pageblock_nr = low_pfn >> pageblock_order;
- if (!isolation_suitable(cc, page))
- goto next_pageblock;
+ if (last_pageblock_nr != pageblock_nr) {
+ int mt;
+
+ last_pageblock_nr = pageblock_nr;
+ if (!isolation_suitable(cc, page))
+ goto next_pageblock;
+
+ /*
+ * For async migration, also only scan in MOVABLE
+ * blocks. Async migration is optimistic to see if
+ * the minimum amount of work satisfies the allocation
+ */
+ mt = get_pageblock_migratetype(page);
+ if (!cc->sync && !migrate_async_suitable(mt)) {
+ cc->finished_update_migrate = true;
+ skipped_async_unsuitable = true;
+ goto next_pageblock;
+ }
+ }
/*
* Skip if free. page_order cannot be used without zone->lock
@@ -537,18 +555,6 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
continue;
/*
- * For async migration, also only scan in MOVABLE blocks. Async
- * migration is optimistic to see if the minimum amount of work
- * satisfies the allocation
- */
- if (!cc->sync && last_pageblock_nr != pageblock_nr &&
- !migrate_async_suitable(get_pageblock_migratetype(page))) {
- cc->finished_update_migrate = true;
- skipped_async_unsuitable = true;
- goto next_pageblock;
- }
-
- /*
* Check may be lockless but that's ok as we recheck later.
* It's possible to migrate LRU pages and balloon pages
* Skip any other type of page
@@ -557,11 +563,7 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
if (unlikely(balloon_page_movable(page))) {
if (locked && balloon_page_isolate(page)) {
/* Successfully isolated */
- cc->finished_update_migrate = true;
- list_add(&page->lru, migratelist);
- cc->nr_migratepages++;
- nr_isolated++;
- goto check_compact_cluster;
+ goto isolate_success;
}
}
continue;
@@ -607,12 +609,6 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
continue;
}
- if (!cc->sync)
- mode |= ISOLATE_ASYNC_MIGRATE;
-
- if (unevictable)
- mode |= ISOLATE_UNEVICTABLE;
-
lruvec = mem_cgroup_page_lruvec(page, zone);
/* Try isolate the page */
@@ -622,13 +618,14 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
VM_BUG_ON_PAGE(PageTransCompound(page), page);
/* Successfully isolated */
- cc->finished_update_migrate = true;
del_page_from_lru_list(page, lruvec, page_lru(page));
+
+isolate_success:
+ cc->finished_update_migrate = true;
list_add(&page->lru, migratelist);
cc->nr_migratepages++;
nr_isolated++;
-check_compact_cluster:
/* Avoid isolating too much */
if (cc->nr_migratepages == COMPACT_CLUSTER_MAX) {
++low_pfn;
@@ -639,7 +636,6 @@ check_compact_cluster:
next_pageblock:
low_pfn = ALIGN(low_pfn + 1, pageblock_nr_pages) - 1;
- last_pageblock_nr = pageblock_nr;
}
acct_isolated(zone, locked, cc);