From 8449d21fb49e9824e2736c5febd6b5d287cd2ba1 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Mon, 8 Oct 2012 16:34:06 -0700 Subject: mm, thp: fix mlock statistics NR_MLOCK is only accounted in single page units: there's no logic to handle transparent hugepages. This patch checks the appropriate number of pages to adjust the statistics by so that the correct amount of memory is reflected. Currently: $ grep Mlocked /proc/meminfo Mlocked: 19636 kB #define MAP_SIZE (4 << 30) /* 4GB */ void *ptr = mmap(NULL, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0); mlock(ptr, MAP_SIZE); $ grep Mlocked /proc/meminfo Mlocked: 29844 kB munlock(ptr, MAP_SIZE); $ grep Mlocked /proc/meminfo Mlocked: 19636 kB And with this patch: $ grep Mlock /proc/meminfo Mlocked: 19636 kB mlock(ptr, MAP_SIZE); $ grep Mlock /proc/meminfo Mlocked: 4213664 kB munlock(ptr, MAP_SIZE); $ grep Mlock /proc/meminfo Mlocked: 19636 kB Signed-off-by: David Rientjes Reported-by: Hugh Dickens Acked-by: Hugh Dickins Reviewed-by: Andrea Arcangeli Cc: Naoya Horiguchi Cc: KAMEZAWA Hiroyuki Cc: Johannes Weiner Reviewed-by: Michel Lespinasse Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mlock.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'mm/mlock.c') diff --git a/mm/mlock.c b/mm/mlock.c index de732159289..f0b9ce572fc 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -56,7 +56,8 @@ void clear_page_mlock(struct page *page) if (!TestClearPageMlocked(page)) return; - dec_zone_page_state(page, NR_MLOCK); + mod_zone_page_state(page_zone(page), NR_MLOCK, + -hpage_nr_pages(page)); count_vm_event(UNEVICTABLE_PGCLEARED); if (!isolate_lru_page(page)) { putback_lru_page(page); @@ -78,7 +79,8 @@ void mlock_vma_page(struct page *page) BUG_ON(!PageLocked(page)); if (!TestSetPageMlocked(page)) { - inc_zone_page_state(page, NR_MLOCK); + mod_zone_page_state(page_zone(page), NR_MLOCK, + hpage_nr_pages(page)); count_vm_event(UNEVICTABLE_PGMLOCKED); if (!isolate_lru_page(page)) putback_lru_page(page); @@ -105,7 +107,8 @@ void munlock_vma_page(struct page *page) BUG_ON(!PageLocked(page)); if (TestClearPageMlocked(page)) { - dec_zone_page_state(page, NR_MLOCK); + mod_zone_page_state(page_zone(page), NR_MLOCK, + -hpage_nr_pages(page)); if (!isolate_lru_page(page)) { int ret = SWAP_AGAIN; -- cgit v1.2.3