diff options
author | Arve Hjønnevåg <arve@android.com> | 2009-03-18 17:27:31 -0700 |
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committer | Arve Hjønnevåg <arve@android.com> | 2010-02-03 20:48:14 -0800 |
commit | 675bed294c5136b04e283f647e5c73fb897cfd19 (patch) | |
tree | b3d005f3933e83fec1896d156aa49dd54f9067d2 /mm | |
parent | c177d04116de6acff4d41706df54cf6c909aa5a2 (diff) |
mm: Check if any page in a pageblock is reserved before marking it MIGRATE_RESERVE
This fixes a problem where the first pageblock got marked MIGRATE_RESERVE even
though it only had a few free pages. This in turn caused no contiguous memory
to be reserved and frequent kswapd wakeups that emptied the caches to get more
contiguous memory.
Diffstat (limited to 'mm')
-rw-r--r-- | mm/page_alloc.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 70d43bf00dc6..cfaa29bbc733 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2859,6 +2859,20 @@ static inline unsigned long wait_table_bits(unsigned long size) #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1)) /* + * Check if a pageblock contains reserved pages + */ +static int pageblock_is_reserved(unsigned long start_pfn) +{ + unsigned long end_pfn = start_pfn + pageblock_nr_pages; + unsigned long pfn; + + for (pfn = start_pfn; pfn < end_pfn; pfn++) + if (PageReserved(pfn_to_page(pfn))) + return 1; + return 0; +} + +/* * Mark a number of pageblocks as MIGRATE_RESERVE. The number * of blocks reserved is based on min_wmark_pages(zone). The memory within * the reserve will tend to store contiguous free pages. Setting min_free_kbytes @@ -2897,7 +2911,7 @@ static void setup_zone_migrate_reserve(struct zone *zone) continue; /* Blocks with reserved pages will never free, skip them. */ - if (PageReserved(page)) + if (pageblock_is_reserved(pfn)) continue; block_migratetype = get_pageblock_migratetype(page); |