diff options
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 120 |
1 files changed, 75 insertions, 45 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index 399d54e8a82..d9fc2dce93a 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -51,6 +51,12 @@ #define CREATE_TRACE_POINTS #include <trace/events/vmscan.h> +enum lumpy_mode { + LUMPY_MODE_NONE, + LUMPY_MODE_ASYNC, + LUMPY_MODE_SYNC, +}; + struct scan_control { /* Incremented by the number of inactive pages that were scanned */ unsigned long nr_scanned; @@ -82,7 +88,7 @@ struct scan_control { * Intend to reclaim enough continuous memory rather than reclaim * enough amount of memory. i.e, mode for high order allocation. */ - bool lumpy_reclaim_mode; + enum lumpy_mode lumpy_reclaim_mode; /* Which cgroup do we reclaim from */ struct mem_cgroup *mem_cgroup; @@ -265,6 +271,36 @@ unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask, return ret; } +static void set_lumpy_reclaim_mode(int priority, struct scan_control *sc, + bool sync) +{ + enum lumpy_mode mode = sync ? LUMPY_MODE_SYNC : LUMPY_MODE_ASYNC; + + /* + * Some reclaim have alredy been failed. No worth to try synchronous + * lumpy reclaim. + */ + if (sync && sc->lumpy_reclaim_mode == LUMPY_MODE_NONE) + return; + + /* + * If we need a large contiguous chunk of memory, or have + * trouble getting a small set of contiguous pages, we + * will reclaim both active and inactive pages. + */ + if (sc->order > PAGE_ALLOC_COSTLY_ORDER) + sc->lumpy_reclaim_mode = mode; + else if (sc->order && priority < DEF_PRIORITY - 2) + sc->lumpy_reclaim_mode = mode; + else + sc->lumpy_reclaim_mode = LUMPY_MODE_NONE; +} + +static void disable_lumpy_reclaim_mode(struct scan_control *sc) +{ + sc->lumpy_reclaim_mode = LUMPY_MODE_NONE; +} + static inline int is_page_cache_freeable(struct page *page) { /* @@ -275,7 +311,8 @@ static inline int is_page_cache_freeable(struct page *page) return page_count(page) - page_has_private(page) == 2; } -static int may_write_to_queue(struct backing_dev_info *bdi) +static int may_write_to_queue(struct backing_dev_info *bdi, + struct scan_control *sc) { if (current->flags & PF_SWAPWRITE) return 1; @@ -283,6 +320,10 @@ static int may_write_to_queue(struct backing_dev_info *bdi) return 1; if (bdi == current->backing_dev_info) return 1; + + /* lumpy reclaim for hugepage often need a lot of write */ + if (sc->order > PAGE_ALLOC_COSTLY_ORDER) + return 1; return 0; } @@ -307,12 +348,6 @@ static void handle_write_error(struct address_space *mapping, unlock_page(page); } -/* Request for sync pageout. */ -enum pageout_io { - PAGEOUT_IO_ASYNC, - PAGEOUT_IO_SYNC, -}; - /* possible outcome of pageout() */ typedef enum { /* failed to write page out, page is locked */ @@ -330,7 +365,7 @@ typedef enum { * Calls ->writepage(). */ static pageout_t pageout(struct page *page, struct address_space *mapping, - enum pageout_io sync_writeback) + struct scan_control *sc) { /* * If the page is dirty, only perform writeback if that write @@ -366,8 +401,10 @@ static pageout_t pageout(struct page *page, struct address_space *mapping, } if (mapping->a_ops->writepage == NULL) return PAGE_ACTIVATE; - if (!may_write_to_queue(mapping->backing_dev_info)) + if (!may_write_to_queue(mapping->backing_dev_info, sc)) { + disable_lumpy_reclaim_mode(sc); return PAGE_KEEP; + } if (clear_page_dirty_for_io(page)) { int res; @@ -393,7 +430,8 @@ static pageout_t pageout(struct page *page, struct address_space *mapping, * direct reclaiming a large contiguous area and the * first attempt to free a range of pages fails. */ - if (PageWriteback(page) && sync_writeback == PAGEOUT_IO_SYNC) + if (PageWriteback(page) && + sc->lumpy_reclaim_mode == LUMPY_MODE_SYNC) wait_on_page_writeback(page); if (!PageWriteback(page)) { @@ -401,7 +439,7 @@ static pageout_t pageout(struct page *page, struct address_space *mapping, ClearPageReclaim(page); } trace_mm_vmscan_writepage(page, - trace_reclaim_flags(page, sync_writeback)); + trace_reclaim_flags(page, sc->lumpy_reclaim_mode)); inc_zone_page_state(page, NR_VMSCAN_WRITE); return PAGE_SUCCESS; } @@ -579,7 +617,7 @@ static enum page_references page_check_references(struct page *page, referenced_page = TestClearPageReferenced(page); /* Lumpy reclaim - ignore references */ - if (sc->lumpy_reclaim_mode) + if (sc->lumpy_reclaim_mode != LUMPY_MODE_NONE) return PAGEREF_RECLAIM; /* @@ -643,8 +681,7 @@ static noinline_for_stack void free_page_list(struct list_head *free_pages) * shrink_page_list() returns the number of reclaimed pages */ static unsigned long shrink_page_list(struct list_head *page_list, - struct scan_control *sc, - enum pageout_io sync_writeback) + struct scan_control *sc) { LIST_HEAD(ret_pages); LIST_HEAD(free_pages); @@ -693,10 +730,13 @@ static unsigned long shrink_page_list(struct list_head *page_list, * for any page for which writeback has already * started. */ - if (sync_writeback == PAGEOUT_IO_SYNC && may_enter_fs) + if (sc->lumpy_reclaim_mode == LUMPY_MODE_SYNC && + may_enter_fs) wait_on_page_writeback(page); - else - goto keep_locked; + else { + unlock_page(page); + goto keep_lumpy; + } } references = page_check_references(page, sc); @@ -750,14 +790,17 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto keep_locked; /* Page is dirty, try to write it out here */ - switch (pageout(page, mapping, sync_writeback)) { + switch (pageout(page, mapping, sc)) { case PAGE_KEEP: goto keep_locked; case PAGE_ACTIVATE: goto activate_locked; case PAGE_SUCCESS: - if (PageWriteback(page) || PageDirty(page)) + if (PageWriteback(page)) + goto keep_lumpy; + if (PageDirty(page)) goto keep; + /* * A synchronous write - probably a ramdisk. Go * ahead and try to reclaim the page. @@ -840,6 +883,7 @@ cull_mlocked: try_to_free_swap(page); unlock_page(page); putback_lru_page(page); + disable_lumpy_reclaim_mode(sc); continue; activate_locked: @@ -852,6 +896,8 @@ activate_locked: keep_locked: unlock_page(page); keep: + disable_lumpy_reclaim_mode(sc); +keep_lumpy: list_add(&page->lru, &ret_pages); VM_BUG_ON(PageLRU(page) || PageUnevictable(page)); } @@ -1252,7 +1298,7 @@ static inline bool should_reclaim_stall(unsigned long nr_taken, return false; /* Only stall on lumpy reclaim */ - if (!sc->lumpy_reclaim_mode) + if (sc->lumpy_reclaim_mode == LUMPY_MODE_NONE) return false; /* If we have relaimed everything on the isolated list, no stall */ @@ -1297,15 +1343,15 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, return SWAP_CLUSTER_MAX; } - + set_lumpy_reclaim_mode(priority, sc, false); lru_add_drain(); spin_lock_irq(&zone->lru_lock); if (scanning_global_lru(sc)) { nr_taken = isolate_pages_global(nr_to_scan, &page_list, &nr_scanned, sc->order, - sc->lumpy_reclaim_mode ? - ISOLATE_BOTH : ISOLATE_INACTIVE, + sc->lumpy_reclaim_mode == LUMPY_MODE_NONE ? + ISOLATE_INACTIVE : ISOLATE_BOTH, zone, 0, file); zone->pages_scanned += nr_scanned; if (current_is_kswapd()) @@ -1317,8 +1363,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, } else { nr_taken = mem_cgroup_isolate_pages(nr_to_scan, &page_list, &nr_scanned, sc->order, - sc->lumpy_reclaim_mode ? - ISOLATE_BOTH : ISOLATE_INACTIVE, + sc->lumpy_reclaim_mode == LUMPY_MODE_NONE ? + ISOLATE_INACTIVE : ISOLATE_BOTH, zone, sc->mem_cgroup, 0, file); /* @@ -1336,7 +1382,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, spin_unlock_irq(&zone->lru_lock); - nr_reclaimed = shrink_page_list(&page_list, sc, PAGEOUT_IO_ASYNC); + nr_reclaimed = shrink_page_list(&page_list, sc); /* Check if we should syncronously wait for writeback */ if (should_reclaim_stall(nr_taken, nr_reclaimed, priority, sc)) { @@ -1347,7 +1393,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, nr_active = clear_active_flags(&page_list, NULL); count_vm_events(PGDEACTIVATE, nr_active); - nr_reclaimed += shrink_page_list(&page_list, sc, PAGEOUT_IO_SYNC); + set_lumpy_reclaim_mode(priority, sc, true); + nr_reclaimed += shrink_page_list(&page_list, sc); } local_irq_disable(); @@ -1739,21 +1786,6 @@ out: } } -static void set_lumpy_reclaim_mode(int priority, struct scan_control *sc) -{ - /* - * If we need a large contiguous chunk of memory, or have - * trouble getting a small set of contiguous pages, we - * will reclaim both active and inactive pages. - */ - if (sc->order > PAGE_ALLOC_COSTLY_ORDER) - sc->lumpy_reclaim_mode = 1; - else if (sc->order && priority < DEF_PRIORITY - 2) - sc->lumpy_reclaim_mode = 1; - else - sc->lumpy_reclaim_mode = 0; -} - /* * This is a basic per-zone page freer. Used by both kswapd and direct reclaim. */ @@ -1768,8 +1800,6 @@ static void shrink_zone(int priority, struct zone *zone, get_scan_count(zone, sc, nr, priority); - set_lumpy_reclaim_mode(priority, sc); - while (nr[LRU_INACTIVE_ANON] || nr[LRU_ACTIVE_FILE] || nr[LRU_INACTIVE_FILE]) { for_each_evictable_lru(l) { |