summaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
Diffstat (limited to 'mm')
-rw-r--r--mm/compaction.c89
1 files changed, 80 insertions, 9 deletions
diff --git a/mm/compaction.c b/mm/compaction.c
index 329973a1ae45..7487067b4613 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -638,12 +638,13 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
{
struct zone *zone = cc->zone;
unsigned long nr_scanned = 0, nr_isolated = 0;
- struct list_head *migratelist = &cc->migratepages;
struct lruvec *lruvec;
unsigned long flags = 0;
bool locked = false;
struct page *page = NULL, *valid_page = NULL;
unsigned long start_pfn = low_pfn;
+ bool skip_on_failure = false;
+ unsigned long next_skip_pfn = 0;
/*
* Ensure that there are not too many pages isolated from the LRU
@@ -664,10 +665,37 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
if (compact_should_abort(cc))
return 0;
+ if (cc->direct_compaction && (cc->mode == MIGRATE_ASYNC)) {
+ skip_on_failure = true;
+ next_skip_pfn = block_end_pfn(low_pfn, cc->order);
+ }
+
/* Time to isolate some pages for migration */
for (; low_pfn < end_pfn; low_pfn++) {
bool is_lru;
+ if (skip_on_failure && low_pfn >= next_skip_pfn) {
+ /*
+ * We have isolated all migration candidates in the
+ * previous order-aligned block, and did not skip it due
+ * to failure. We should migrate the pages now and
+ * hopefully succeed compaction.
+ */
+ if (nr_isolated)
+ break;
+
+ /*
+ * We failed to isolate in the previous order-aligned
+ * block. Set the new boundary to the end of the
+ * current block. Note we can't simply increase
+ * next_skip_pfn by 1 << order, as low_pfn might have
+ * been incremented by a higher number due to skipping
+ * a compound or a high-order buddy page in the
+ * previous loop iteration.
+ */
+ next_skip_pfn = block_end_pfn(low_pfn, cc->order);
+ }
+
/*
* Periodically drop the lock (if held) regardless of its
* contention, to give chance to IRQs. Abort async compaction
@@ -679,7 +707,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
break;
if (!pfn_valid_within(low_pfn))
- continue;
+ goto isolate_fail;
nr_scanned++;
page = pfn_to_page(low_pfn);
@@ -734,11 +762,11 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
if (likely(comp_order < MAX_ORDER))
low_pfn += (1UL << comp_order) - 1;
- continue;
+ goto isolate_fail;
}
if (!is_lru)
- continue;
+ goto isolate_fail;
/*
* Migration will fail if an anonymous page is pinned in memory,
@@ -747,7 +775,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
*/
if (!page_mapping(page) &&
page_count(page) > page_mapcount(page))
- continue;
+ goto isolate_fail;
/* If we already hold the lock, we can skip some rechecking */
if (!locked) {
@@ -758,7 +786,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
/* Recheck PageLRU and PageCompound under lock */
if (!PageLRU(page))
- continue;
+ goto isolate_fail;
/*
* Page become compound since the non-locked check,
@@ -767,7 +795,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
*/
if (unlikely(PageCompound(page))) {
low_pfn += (1UL << compound_order(page)) - 1;
- continue;
+ goto isolate_fail;
}
}
@@ -775,7 +803,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
/* Try isolate the page */
if (__isolate_lru_page(page, isolate_mode) != 0)
- continue;
+ goto isolate_fail;
VM_BUG_ON_PAGE(PageCompound(page), page);
@@ -783,7 +811,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
del_page_from_lru_list(page, lruvec, page_lru(page));
isolate_success:
- list_add(&page->lru, migratelist);
+ list_add(&page->lru, &cc->migratepages);
cc->nr_migratepages++;
nr_isolated++;
@@ -801,6 +829,37 @@ isolate_success:
++low_pfn;
break;
}
+
+ continue;
+isolate_fail:
+ if (!skip_on_failure)
+ continue;
+
+ /*
+ * We have isolated some pages, but then failed. Release them
+ * instead of migrating, as we cannot form the cc->order buddy
+ * page anyway.
+ */
+ if (nr_isolated) {
+ if (locked) {
+ spin_unlock_irqrestore(&zone->lru_lock, flags);
+ locked = false;
+ }
+ acct_isolated(zone, cc);
+ putback_movable_pages(&cc->migratepages);
+ cc->nr_migratepages = 0;
+ cc->last_migrated_pfn = 0;
+ nr_isolated = 0;
+ }
+
+ if (low_pfn < next_skip_pfn) {
+ low_pfn = next_skip_pfn - 1;
+ /*
+ * The check near the loop beginning would have updated
+ * next_skip_pfn too, but this is a bit simpler.
+ */
+ next_skip_pfn += 1UL << cc->order;
+ }
}
/*
@@ -1401,6 +1460,18 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
ret = COMPACT_CONTENDED;
goto out;
}
+ /*
+ * We failed to migrate at least one page in the current
+ * order-aligned block, so skip the rest of it.
+ */
+ if (cc->direct_compaction &&
+ (cc->mode == MIGRATE_ASYNC)) {
+ cc->migrate_pfn = block_end_pfn(
+ cc->migrate_pfn - 1, cc->order);
+ /* Draining pcplists is useless in this case */
+ cc->last_migrated_pfn = 0;
+
+ }
}
check_drain: