diff --git a/mm/compaction.c b/mm/compaction.c index f4e2c166880b0583dd88ba33190297a0ffa28ec7..cc46db36e7089956977d549298424622d3ec3c42 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -660,7 +660,7 @@ static void isolate_freepages(struct zone *zone, * is the end of the pageblock the migration scanner is using. */ pfn = cc->free_pfn; - low_pfn = cc->migrate_pfn + pageblock_nr_pages; + low_pfn = ALIGN(cc->migrate_pfn + 1, pageblock_nr_pages); /* * Take care that if the migration scanner is at the end of the zone @@ -676,7 +676,7 @@ static void isolate_freepages(struct zone *zone, * pages on cc->migratepages. We stop searching if the migrate * and free page scanners meet or enough free pages are isolated. */ - for (; pfn > low_pfn && cc->nr_migratepages > nr_freepages; + for (; pfn >= low_pfn && cc->nr_migratepages > nr_freepages; pfn -= pageblock_nr_pages) { unsigned long isolated; @@ -738,7 +738,14 @@ static void isolate_freepages(struct zone *zone, /* split_free_page does not map the pages */ map_pages(freelist); - cc->free_pfn = high_pfn; + /* + * If we crossed the migrate scanner, we want to keep it that way + * so that compact_finished() may detect this + */ + if (pfn < low_pfn) + cc->free_pfn = max(pfn, zone->zone_start_pfn); + else + cc->free_pfn = high_pfn; cc->nr_freepages = nr_freepages; } @@ -1005,7 +1012,11 @@ static int compact_zone(struct zone *zone, struct compact_control *cc) if (err) { putback_movable_pages(&cc->migratepages); cc->nr_migratepages = 0; - if (err == -ENOMEM) { + /* + * migrate_pages() may return -ENOMEM when scanners meet + * and we want compact_finished() to detect it + */ + if (err == -ENOMEM && cc->free_pfn > cc->migrate_pfn) { ret = COMPACT_PARTIAL; goto out; }