diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h index bdaf32f8a874..82f693395ac5 100644 --- a/include/trace/events/vmscan.h +++ b/include/trace/events/vmscan.h @@ -13,7 +13,7 @@ #define RECLAIM_WB_ANON 0x0001u #define RECLAIM_WB_FILE 0x0002u #define RECLAIM_WB_MIXED 0x0010u -#define RECLAIM_WB_SYNC 0x0004u +#define RECLAIM_WB_SYNC 0x0004u /* Unused, all reclaim async */ #define RECLAIM_WB_ASYNC 0x0008u #define show_reclaim_flags(flags) \ @@ -27,13 +27,13 @@ #define trace_reclaim_flags(page, sync) ( \ (page_is_file_cache(page) ? RECLAIM_WB_FILE : RECLAIM_WB_ANON) | \ - (sync & RECLAIM_MODE_SYNC ? RECLAIM_WB_SYNC : RECLAIM_WB_ASYNC) \ + (RECLAIM_WB_ASYNC) \ ) -#define trace_shrink_flags(file, sync) ( \ - (sync & RECLAIM_MODE_SYNC ? RECLAIM_WB_MIXED : \ - (file ? RECLAIM_WB_FILE : RECLAIM_WB_ANON)) | \ - (sync & RECLAIM_MODE_SYNC ? RECLAIM_WB_SYNC : RECLAIM_WB_ASYNC) \ +#define trace_shrink_flags(file, sync) \ + ( \ + (file ? RECLAIM_WB_FILE : RECLAIM_WB_ANON) | \ + (RECLAIM_WB_ASYNC) \ ) TRACE_EVENT(mm_vmscan_kswapd_sleep, diff --git a/mm/vmscan.c b/mm/vmscan.c index 546d02ce90ee..e27f27d4cc19 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -56,15 +56,11 @@ /* * reclaim_mode determines how the inactive list is shrunk * RECLAIM_MODE_SINGLE: Reclaim only order-0 pages - * RECLAIM_MODE_ASYNC: Do not block - * RECLAIM_MODE_SYNC: Allow blocking e.g. call wait_on_page_writeback * RECLAIM_MODE_COMPACTION: For high-order allocations, reclaim a number of * order-0 pages and then compact the zone */ typedef unsigned __bitwise__ reclaim_mode_t; #define RECLAIM_MODE_SINGLE ((__force reclaim_mode_t)0x01u) -#define RECLAIM_MODE_ASYNC ((__force reclaim_mode_t)0x02u) -#define RECLAIM_MODE_SYNC ((__force reclaim_mode_t)0x04u) #define RECLAIM_MODE_COMPACTION ((__force reclaim_mode_t)0x10u) struct scan_control { @@ -360,12 +356,8 @@ out: return ret; } -static void set_reclaim_mode(int priority, struct scan_control *sc, - bool sync) +static void set_reclaim_mode(int priority, struct scan_control *sc) { - /* Sync reclaim used only for compaction */ - reclaim_mode_t syncmode = sync ? RECLAIM_MODE_SYNC : RECLAIM_MODE_ASYNC; - /* * Restrict reclaim/compaction to costly allocations or when * under memory pressure @@ -373,14 +365,14 @@ static void set_reclaim_mode(int priority, struct scan_control *sc, if (COMPACTION_BUILD && sc->order && (sc->order > PAGE_ALLOC_COSTLY_ORDER || priority < DEF_PRIORITY - 2)) - sc->reclaim_mode = RECLAIM_MODE_COMPACTION | syncmode; + sc->reclaim_mode = RECLAIM_MODE_COMPACTION; else - sc->reclaim_mode = RECLAIM_MODE_SINGLE | RECLAIM_MODE_ASYNC; + sc->reclaim_mode = RECLAIM_MODE_SINGLE; } static void reset_reclaim_mode(struct scan_control *sc) { - sc->reclaim_mode = RECLAIM_MODE_SINGLE | RECLAIM_MODE_ASYNC; + sc->reclaim_mode = RECLAIM_MODE_SINGLE; } static inline int is_page_cache_freeable(struct page *page) @@ -791,19 +783,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, if (PageWriteback(page)) { nr_writeback++; - /* - * Synchronous reclaim cannot queue pages for - * writeback due to the possibility of stack overflow - * but if it encounters a page under writeback, wait - * for the IO to complete. - */ - if ((sc->reclaim_mode & RECLAIM_MODE_SYNC) && - may_enter_fs) - wait_on_page_writeback(page); - else { - unlock_page(page); - goto keep_reclaim_mode; - } + unlock_page(page); + goto keep; } references = page_check_references(page, mz, sc); @@ -886,7 +867,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto activate_locked; case PAGE_SUCCESS: if (PageWriteback(page)) - goto keep_reclaim_mode; + goto keep; if (PageDirty(page)) goto keep; @@ -985,8 +966,6 @@ activate_locked: keep_locked: unlock_page(page); keep: - reset_reclaim_mode(sc); -keep_reclaim_mode: list_add(&page->lru, &ret_pages); VM_BUG_ON(PageLRU(page) || PageUnevictable(page)); } @@ -1341,47 +1320,6 @@ update_isolated_counts(struct mem_cgroup_zone *mz, preempt_enable(); } -/* - * Returns true if a direct reclaim should wait on pages under writeback. - * - * If we are direct reclaiming for contiguous pages and we do not reclaim - * everything in the list, try again and wait for writeback IO to complete. - * This will stall high-order allocations noticeably. Only do that when really - * need to free the pages under high memory pressure. - */ -static inline bool should_reclaim_stall(unsigned long nr_taken, - unsigned long nr_freed, - int priority, - struct scan_control *sc) -{ - int stall_priority; - - /* kswapd should not stall on sync IO */ - if (current_is_kswapd()) - return false; - - /* Only stall for memory compaction */ - if (sc->reclaim_mode & RECLAIM_MODE_SINGLE) - return false; - - /* If we have reclaimed everything on the isolated list, no stall */ - if (nr_freed == nr_taken) - return false; - - /* - * For high-order allocations, there are two stall thresholds. - * High-cost allocations stall immediately where as lower - * order allocations such as stacks require the scanning - * priority to be much higher before stalling. - */ - if (sc->order > PAGE_ALLOC_COSTLY_ORDER) - stall_priority = DEF_PRIORITY; - else - stall_priority = DEF_PRIORITY / 3; - - return priority <= stall_priority; -} - /* * shrink_inactive_list() is a helper for shrink_zone(). It returns the number * of reclaimed pages @@ -1410,7 +1348,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz, return SWAP_CLUSTER_MAX; } - set_reclaim_mode(priority, sc, false); + set_reclaim_mode(priority, sc); lru_add_drain(); @@ -1442,13 +1380,6 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz, nr_reclaimed = shrink_page_list(&page_list, mz, sc, priority, &nr_dirty, &nr_writeback); - /* Check if we should syncronously wait for writeback */ - if (should_reclaim_stall(nr_taken, nr_reclaimed, priority, sc)) { - set_reclaim_mode(priority, sc, true); - nr_reclaimed += shrink_page_list(&page_list, mz, sc, - priority, &nr_dirty, &nr_writeback); - } - spin_lock_irq(&zone->lru_lock); reclaim_stat->recent_scanned[0] += nr_anon;