diff options
| -rw-r--r-- | mm/page_alloc.c | 50 |
1 files changed, 34 insertions, 16 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 2e22ce5675ca..222299b5c0e6 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1955,10 +1955,12 @@ int find_suitable_fallback(struct free_area *area, unsigned int order, } /* - * Reserve a pageblock for exclusive use of high-order atomic allocations if - * there are no empty page blocks that contain a page with a suitable order + * Reserve the pageblock(s) surrounding an allocation request for + * exclusive use of high-order atomic allocations if there are no + * empty page blocks that contain a page with a suitable order */ -static void reserve_highatomic_pageblock(struct page *page, struct zone *zone) +static void reserve_highatomic_pageblock(struct page *page, int order, + struct zone *zone) { int mt; unsigned long max_managed, flags; @@ -1984,10 +1986,17 @@ static void reserve_highatomic_pageblock(struct page *page, struct zone *zone) /* Yoink! */ mt = get_pageblock_migratetype(page); /* Only reserve normal pageblocks (i.e., they can merge with others) */ - if (migratetype_is_mergeable(mt)) - if (move_freepages_block(zone, page, mt, - MIGRATE_HIGHATOMIC) != -1) - zone->nr_reserved_highatomic += pageblock_nr_pages; + if (!migratetype_is_mergeable(mt)) + goto out_unlock; + + if (order < pageblock_order) { + if (move_freepages_block(zone, page, mt, MIGRATE_HIGHATOMIC) == -1) + goto out_unlock; + zone->nr_reserved_highatomic += pageblock_nr_pages; + } else { + change_pageblock_range(page, order, MIGRATE_HIGHATOMIC); + zone->nr_reserved_highatomic += 1 << order; + } out_unlock: spin_unlock_irqrestore(&zone->lock, flags); @@ -1999,7 +2008,7 @@ out_unlock: * intense memory pressure but failed atomic allocations should be easier * to recover from than an OOM. * - * If @force is true, try to unreserve a pageblock even though highatomic + * If @force is true, try to unreserve pageblocks even though highatomic * pageblock is exhausted. */ static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, @@ -2041,6 +2050,7 @@ static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, * adjust the count once. */ if (is_migrate_highatomic(mt)) { + unsigned long size; /* * It should never happen but changes to * locking could inadvertently allow a per-cpu @@ -2048,9 +2058,9 @@ static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, * while unreserving so be safe and watch for * underflows. */ - zone->nr_reserved_highatomic -= min( - pageblock_nr_pages, - zone->nr_reserved_highatomic); + size = max(pageblock_nr_pages, 1UL << order); + size = min(size, zone->nr_reserved_highatomic); + zone->nr_reserved_highatomic -= size; } /* @@ -2062,11 +2072,19 @@ static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, * of pageblocks that cannot be completely freed * may increase. */ - ret = move_freepages_block(zone, page, mt, - ac->migratetype); + if (order < pageblock_order) + ret = move_freepages_block(zone, page, mt, + ac->migratetype); + else { + move_to_free_list(page, zone, order, mt, + ac->migratetype); + change_pageblock_range(page, order, + ac->migratetype); + ret = 1; + } /* - * Reserving this block already succeeded, so this should - * not fail on zone boundaries. + * Reserving the block(s) already succeeded, + * so this should not fail on zone boundaries. */ WARN_ON_ONCE(ret == -1); if (ret > 0) { @@ -3406,7 +3424,7 @@ try_this_zone: * if the pageblock should be reserved for the future */ if (unlikely(alloc_flags & ALLOC_HIGHATOMIC)) - reserve_highatomic_pageblock(page, zone); + reserve_highatomic_pageblock(page, order, zone); return page; } else { |