From mboxrd@z Thu Jan 1 00:00:00 1970 From: "KOSAKI Motohiro" Subject: [PATCH 4/8][for -mm] mem_notify v6: memory_pressure_notify() caller Date: Sun, 10 Feb 2008 00:24:28 +0900 Message-ID: <2f11576a0802090724s679258c4g7414e0a6983f4706@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: kosaki.motohiro@jp.fujitsu.com, "Marcelo Tosatti" , "Daniel Spang" , "Rik van Riel" , "Andrew Morton" , "Alan Cox" , linux-fsdevel@vger.kernel.org, "Pavel Machek" , "Al Boldi" , "Jon Masters" , "Zan Lynx" To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Return-path: Received: from py-out-1112.google.com ([64.233.166.177]:38755 "EHLO py-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751544AbYBIPYa (ORCPT ); Sat, 9 Feb 2008 10:24:30 -0500 Received: by py-out-1112.google.com with SMTP id u52so5947037pyb.10 for ; Sat, 09 Feb 2008 07:24:29 -0800 (PST) Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-ID: the notification point to happen whenever the VM moves an anonymous page to the inactive list - this is a pretty good indication that there are unused anonymous pages present which will be very likely swapped out soon. and, It is judged out of trouble at the fllowing situations. o memory pressure decrease and stop moves an anonymous page to the inactive list. o free pages increase than (pages_high+lowmem_reserve)*2. ChangeLog: v5: add out of trouble notify to exit of balance_pgdat(). Signed-off-by: Marcelo Tosatti Signed-off-by: KOSAKI Motohiro --- mm/page_alloc.c | 12 ++++++++++++ mm/vmscan.c | 26 ++++++++++++++++++++++++++ 2 files changed, 38 insertions(+) Index: b/mm/vmscan.c =================================================================== --- a/mm/vmscan.c 2008-01-23 22:06:08.000000000 +0900 +++ b/mm/vmscan.c 2008-01-23 22:07:57.000000000 +0900 @@ -39,6 +39,7 @@ #include #include #include +#include #include #include @@ -1089,10 +1090,14 @@ static void shrink_active_list(unsigned struct page *page; struct pagevec pvec; int reclaim_mapped = 0; + bool inactivated_anon = 0; if (sc->may_swap) reclaim_mapped = calc_reclaim_mapped(sc, zone, priority); + if (!reclaim_mapped) + memory_pressure_notify(zone, 0); + lru_add_drain(); spin_lock_irq(&zone->lru_lock); pgmoved = sc->isolate_pages(nr_pages, &l_hold, &pgscanned, sc->order, @@ -1116,6 +1121,13 @@ static void shrink_active_list(unsigned if (!reclaim_mapped || (total_swap_pages == 0 && PageAnon(page)) || page_referenced(page, 0, sc->mem_cgroup)) { + /* deal with the case where there is no + * swap but an anonymous page would be + * moved to the inactive list. + */ + if (!total_swap_pages && reclaim_mapped && + PageAnon(page)) + inactivated_anon = 1; list_add(&page->lru, &l_active); continue; } @@ -1123,8 +1135,12 @@ static void shrink_active_list(unsigned list_add(&page->lru, &l_active); continue; } + if (PageAnon(page)) + inactivated_anon = 1; list_add(&page->lru, &l_inactive); } + if (inactivated_anon) + memory_pressure_notify(zone, 1); pagevec_init(&pvec, 1); pgmoved = 0; @@ -1158,6 +1174,8 @@ static void shrink_active_list(unsigned pagevec_strip(&pvec); spin_lock_irq(&zone->lru_lock); } + if (!reclaim_mapped) + memory_pressure_notify(zone, 0); pgmoved = 0; while (!list_empty(&l_active)) { @@ -1659,6 +1677,14 @@ out: goto loop_again; } + for (i = pgdat->nr_zones - 1; i >= 0; i--) { + struct zone *zone = pgdat->node_zones + i; + + if (!populated_zone(zone)) + continue; + memory_pressure_notify(zone, 0); + } + return nr_reclaimed; } Index: b/mm/page_alloc.c =================================================================== --- a/mm/page_alloc.c 2008-01-23 22:06:08.000000000 +0900 +++ b/mm/page_alloc.c 2008-01-23 23:09:32.000000000 +0900 @@ -44,6 +44,7 @@ #include #include #include +#include #include #include @@ -435,6 +436,8 @@ static inline void __free_one_page(struc unsigned long page_idx; int order_size = 1 << order; int migratetype = get_pageblock_migratetype(page); + unsigned long prev_free; + unsigned long notify_threshold; if (unlikely(PageCompound(page))) destroy_compound_page(page, order); @@ -444,6 +447,7 @@ static inline void __free_one_page(struc VM_BUG_ON(page_idx & (order_size - 1)); VM_BUG_ON(bad_range(zone, page)); + prev_free = zone_page_state(zone, NR_FREE_PAGES); __mod_zone_page_state(zone, NR_FREE_PAGES, order_size); while (order < MAX_ORDER-1) { unsigned long combined_idx; @@ -465,6 +469,14 @@ static inline void __free_one_page(struc list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); zone->free_area[order].nr_free++; + + notify_threshold = (zone->pages_high + + zone->lowmem_reserve[MAX_NR_ZONES-1]) * 2; + + if (unlikely((zone->mem_notify_status == 1) && + (prev_free <= notify_threshold) && + (zone_page_state(zone, NR_FREE_PAGES) > notify_threshold))) + memory_pressure_notify(zone, 0); } static inline int free_pages_check(struct page *page)