In shrink_(in)active_list(), we can fail to put into lru, and these pages are reclaimed accidentally. Currently, these pages are not counted for sc->nr_reclaimed, but with this information, we can stop to reclaim earlier, so can reduce overhead of reclaim. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 0f615eb..5d60ae0 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -365,7 +365,7 @@ void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask); extern void __free_pages(struct page *page, unsigned int order); extern void free_pages(unsigned long addr, unsigned int order); extern void free_hot_cold_page(struct page *page, int cold); -extern void free_hot_cold_page_list(struct list_head *list, int cold); +extern unsigned long free_hot_cold_page_list(struct list_head *list, int cold); extern void __free_memcg_kmem_pages(struct page *page, unsigned int order); extern void free_memcg_kmem_pages(unsigned long addr, unsigned int order); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 8fcced7..a5f3952 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1360,14 +1360,18 @@ out: /* * Free a list of 0-order pages */ -void free_hot_cold_page_list(struct list_head *list, int cold) +unsigned long free_hot_cold_page_list(struct list_head *list, int cold) { + unsigned long nr_reclaimed = 0; struct page *page, *next; list_for_each_entry_safe(page, next, list, lru) { trace_mm_page_free_batched(page, cold); free_hot_cold_page(page, cold); + nr_reclaimed++; } + + return nr_reclaimed; } /* diff --git a/mm/vmscan.c b/mm/vmscan.c index 88c5fed..eff2927 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -915,7 +915,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, */ __clear_page_locked(page); free_it: - nr_reclaimed++; /* * Is there need to periodically free_page_list? It would @@ -954,7 +953,7 @@ keep: if (nr_dirty && nr_dirty == nr_congested && global_reclaim(sc)) zone_set_flag(zone, ZONE_CONGESTED); - free_hot_cold_page_list(&free_pages, 1); + nr_reclaimed += free_hot_cold_page_list(&free_pages, 1); list_splice(&ret_pages, page_list); count_vm_events(PGACTIVATE, pgactivate); @@ -1321,7 +1320,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, if (nr_taken == 0) return 0; - nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP, + nr_reclaimed += shrink_page_list(&page_list, zone, sc, TTU_UNMAP, &nr_dirty, &nr_writeback, false); spin_lock_irq(&zone->lru_lock); @@ -1343,7 +1342,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, spin_unlock_irq(&zone->lru_lock); - free_hot_cold_page_list(&page_list, 1); + nr_reclaimed += free_hot_cold_page_list(&page_list, 1); /* * If reclaim is isolating dirty pages under writeback, it implies @@ -1438,7 +1437,7 @@ static void move_active_pages_to_lru(struct lruvec *lruvec, __count_vm_events(PGDEACTIVATE, pgmoved); } -static void shrink_active_list(unsigned long nr_to_scan, +static unsigned long shrink_active_list(unsigned long nr_to_scan, struct lruvec *lruvec, struct scan_control *sc, enum lru_list lru) @@ -1534,7 +1533,7 @@ static void shrink_active_list(unsigned long nr_to_scan, __mod_zone_page_state(zone, NR_ISOLATED_ANON + file, -nr_taken); spin_unlock_irq(&zone->lru_lock); - free_hot_cold_page_list(&l_hold, 1); + return free_hot_cold_page_list(&l_hold, 1); } #ifdef CONFIG_SWAP @@ -1617,7 +1616,8 @@ static unsigned long shrink_list(enum lru_list lru, unsigned long nr_to_scan, { if (is_active_lru(lru)) { if (inactive_list_is_low(lruvec, lru)) - shrink_active_list(nr_to_scan, lruvec, sc, lru); + return shrink_active_list(nr_to_scan, lruvec, sc, lru); + return 0; } @@ -1861,8 +1861,8 @@ static void shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) * rebalance the anon lru active/inactive ratio. */ if (inactive_anon_is_low(lruvec)) - shrink_active_list(SWAP_CLUSTER_MAX, lruvec, - sc, LRU_ACTIVE_ANON); + sc->nr_reclaimed += shrink_active_list(SWAP_CLUSTER_MAX, + lruvec, sc, LRU_ACTIVE_ANON); throttle_vm_writeout(sc->gfp_mask); } @@ -2470,23 +2470,27 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, } #endif -static void age_active_anon(struct zone *zone, struct scan_control *sc) +static unsigned long age_active_anon(struct zone *zone, + struct scan_control *sc) { + unsigned long nr_reclaimed = 0; struct mem_cgroup *memcg; if (!total_swap_pages) - return; + return 0; memcg = mem_cgroup_iter(NULL, NULL, NULL); do { struct lruvec *lruvec = mem_cgroup_zone_lruvec(zone, memcg); if (inactive_anon_is_low(lruvec)) - shrink_active_list(SWAP_CLUSTER_MAX, lruvec, - sc, LRU_ACTIVE_ANON); + nr_reclaimed += shrink_active_list(SWAP_CLUSTER_MAX, + lruvec, sc, LRU_ACTIVE_ANON); memcg = mem_cgroup_iter(NULL, memcg, NULL); } while (memcg); + + return nr_reclaimed; } static bool zone_balanced(struct zone *zone, int order, @@ -2666,7 +2670,7 @@ loop_again: * Do some background aging of the anon list, to give * pages a chance to be referenced before reclaiming. */ - age_active_anon(zone, &sc); + sc.nr_reclaimed += age_active_anon(zone, &sc); /* * If the number of buffer_heads in the machine -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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