From: Lee Schermerhorn Add some event counters to vmstats for testing unevictable/mlock. Some of these might be interesting enough to keep around. Signed-off-by: KOSAKI Motohiro Signed-off-by: Lee Schermerhorn Signed-off-by: Rik van Riel --- include/linux/vmstat.h | 9 +++++++++ mm/internal.h | 4 +++- mm/mlock.c | 33 +++++++++++++++++++++++++-------- mm/vmscan.c | 16 +++++++++++++++- mm/vmstat.c | 10 ++++++++++ 5 files changed, 62 insertions(+), 10 deletions(-) Index: linux-2.6.26-rc5-mm2/include/linux/vmstat.h =================================================================== --- linux-2.6.26-rc5-mm2.orig/include/linux/vmstat.h 2008-06-10 22:23:56.000000000 -0400 +++ linux-2.6.26-rc5-mm2/include/linux/vmstat.h 2008-06-10 22:25:48.000000000 -0400 @@ -41,6 +41,15 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS #ifdef CONFIG_HUGETLB_PAGE HTLB_BUDDY_PGALLOC, HTLB_BUDDY_PGALLOC_FAIL, #endif +#ifdef CONFIG_UNEVICTABLE_LRU + NORECL_PGCULLED, /* culled to noreclaim list */ + NORECL_PGSCANNED, /* scanned for reclaimability */ + NORECL_PGRESCUED, /* rescued from noreclaim list */ + NORECL_PGMLOCKED, + NORECL_PGMUNLOCKED, + NORECL_PGCLEARED, + NORECL_PGSTRANDED, /* unable to isolate on unlock */ +#endif NR_VM_EVENT_ITEMS }; Index: linux-2.6.26-rc5-mm2/mm/vmscan.c =================================================================== --- linux-2.6.26-rc5-mm2.orig/mm/vmscan.c 2008-06-10 22:23:56.000000000 -0400 +++ linux-2.6.26-rc5-mm2/mm/vmscan.c 2008-06-10 22:25:49.000000000 -0400 @@ -468,12 +468,13 @@ int putback_lru_page(struct page *page) { int lru; int ret = 1; + int was_unevictable; VM_BUG_ON(!PageLocked(page)); VM_BUG_ON(PageLRU(page)); lru = !!TestClearPageActive(page); - ClearPageUnevictable(page); /* for page_evictable() */ + was_unevictable = TestClearPageUnevictable(page); /* for page_evictable() */ if (unlikely(!page->mapping)) { /* @@ -493,6 +494,10 @@ int putback_lru_page(struct page *page) lru += page_is_file_cache(page); lru_cache_add_lru(page, lru); mem_cgroup_move_lists(page, lru); +#ifdef CONFIG_UNEVICTABLE_LRU + if (was_unevictable) + count_vm_event(NORECL_PGRESCUED); +#endif } else { /* * Put unevictable pages directly on zone's unevictable @@ -500,6 +505,10 @@ int putback_lru_page(struct page *page) */ add_page_to_unevictable_list(page); mem_cgroup_move_lists(page, LRU_UNEVICTABLE); +#ifdef CONFIG_UNEVICTABLE_LRU + if (!was_unevictable) + count_vm_event(NORECL_PGCULLED); +#endif } put_page(page); /* drop ref from isolate */ @@ -2373,6 +2382,7 @@ static void check_move_unevictable_page( __dec_zone_state(zone, NR_UNEVICTABLE); list_move(&page->lru, &zone->lru[l].list); __inc_zone_state(zone, NR_INACTIVE_ANON + l); + __count_vm_event(NORECL_PGRESCUED); } else { /* * rotate unevictable list @@ -2404,6 +2414,7 @@ void scan_mapping_unevictable_pages(stru while (next < end && pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { int i; + int pg_scanned = 0; zone = NULL; @@ -2412,6 +2423,7 @@ void scan_mapping_unevictable_pages(stru pgoff_t page_index = page->index; struct zone *pagezone = page_zone(page); + pg_scanned++; if (page_index > next) next = page_index; next++; @@ -2442,6 +2454,8 @@ void scan_mapping_unevictable_pages(stru if (zone) spin_unlock_irq(&zone->lru_lock); pagevec_release(&pvec); + + count_vm_events(NORECL_PGSCANNED, pg_scanned); } } Index: linux-2.6.26-rc5-mm2/mm/vmstat.c =================================================================== --- linux-2.6.26-rc5-mm2.orig/mm/vmstat.c 2008-06-10 22:23:56.000000000 -0400 +++ linux-2.6.26-rc5-mm2/mm/vmstat.c 2008-06-10 22:25:48.000000000 -0400 @@ -664,6 +664,16 @@ static const char * const vmstat_text[] "htlb_buddy_alloc_success", "htlb_buddy_alloc_fail", #endif + +#ifdef CONFIG_UNEVICTABLE_LRU + "noreclaim_pgs_culled", + "noreclaim_pgs_scanned", + "noreclaim_pgs_rescued", + "noreclaim_pgs_mlocked", + "noreclaim_pgs_munlocked", + "noreclaim_pgs_cleared", + "noreclaim_pgs_stranded", +#endif #endif }; Index: linux-2.6.26-rc5-mm2/mm/mlock.c =================================================================== --- linux-2.6.26-rc5-mm2.orig/mm/mlock.c 2008-06-10 22:23:56.000000000 -0400 +++ linux-2.6.26-rc5-mm2/mm/mlock.c 2008-06-10 22:25:56.000000000 -0400 @@ -18,6 +18,7 @@ #include #include #include +#include #include "internal.h" @@ -57,6 +58,7 @@ void __clear_page_mlock(struct page *pag VM_BUG_ON(!PageLocked(page)); /* for LRU isolate/putback */ dec_zone_page_state(page, NR_MLOCK); + count_vm_event(NORECL_PGCLEARED); if (!isolate_lru_page(page)) { putback_lru_page(page); } else { @@ -66,6 +68,8 @@ void __clear_page_mlock(struct page *pag lru_add_drain_all(); if (!isolate_lru_page(page)) putback_lru_page(page); + else if (PageUnevictable(page)) + count_vm_event(NORECL_PGSTRANDED); } } @@ -79,6 +83,7 @@ void mlock_vma_page(struct page *page) if (!TestSetPageMlocked(page)) { inc_zone_page_state(page, NR_MLOCK); + count_vm_event(NORECL_PGMLOCKED); if (!isolate_lru_page(page)) putback_lru_page(page); } @@ -109,16 +114,28 @@ static void munlock_vma_page(struct page if (TestClearPageMlocked(page)) { dec_zone_page_state(page, NR_MLOCK); if (!isolate_lru_page(page)) { - try_to_munlock(page); /* maybe relock the page */ + int ret = try_to_munlock(page); + /* + * did try_to_unlock() succeed or punt? + */ + if (ret == SWAP_SUCCESS || ret == SWAP_AGAIN) + count_vm_event(NORECL_PGMUNLOCKED); + putback_lru_page(page); + } else { + /* + * We lost the race. let try_to_unmap() deal + * with it. At least we get the page state and + * mlock stats right. However, page is still on + * the noreclaim list. We'll fix that up when + * the page is eventually freed or we scan the + * noreclaim list. + */ + if (PageUnevictable(page)) + count_vm_event(NORECL_PGSTRANDED); + else + count_vm_event(NORECL_PGMUNLOCKED); } - /* - * Else we lost the race. let try_to_unmap() deal with it. - * At least we get the page state and mlock stats right. - * However, page is still on the noreclaim list. We'll fix - * that up when the page is eventually freed or we scan the - * noreclaim list. - */ } } Index: linux-2.6.26-rc5-mm2/mm/internal.h =================================================================== --- linux-2.6.26-rc5-mm2.orig/mm/internal.h 2008-06-10 22:23:56.000000000 -0400 +++ linux-2.6.26-rc5-mm2/mm/internal.h 2008-06-10 22:25:48.000000000 -0400 @@ -101,8 +101,10 @@ static inline int is_mlocked_vma(struct if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) return 0; - if (!TestSetPageMlocked(page)) + if (!TestSetPageMlocked(page)) { inc_zone_page_state(page, NR_MLOCK); + count_vm_event(NORECL_PGMLOCKED); + } return 1; } -- All Rights Reversed -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/