This is a note to let you know that I've just added the patch titled mm, vmscan: cleanup lru size claculations to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mm-vmscan-cleanup-lru-size-claculations.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From fd538803731e50367b7c59ce4ad3454426a3d671 Mon Sep 17 00:00:00 2001 From: Michal Hocko <mhocko@xxxxxxxx> Date: Wed, 22 Feb 2017 15:45:58 -0800 Subject: mm, vmscan: cleanup lru size claculations From: Michal Hocko <mhocko@xxxxxxxx> commit fd538803731e50367b7c59ce4ad3454426a3d671 upstream. lruvec_lru_size returns the full size of the LRU list while we sometimes need a value reduced only to eligible zones (e.g. for lowmem requests). inactive_list_is_low is one such user. Later patches will add more of them. Add a new parameter to lruvec_lru_size and allow it filter out zones which are not eligible for the given context. Link: http://lkml.kernel.org/r/20170117103702.28542-2-mhocko@xxxxxxxxxx Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx> Acked-by: Hillf Danton <hillf.zj@xxxxxxxxxxxxxxx> Acked-by: Minchan Kim <minchan@xxxxxxxxxx> Acked-by: Mel Gorman <mgorman@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/mmzone.h | 2 - mm/vmscan.c | 81 +++++++++++++++++++++++-------------------------- mm/workingset.c | 2 - 3 files changed, 41 insertions(+), 44 deletions(-) --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -779,7 +779,7 @@ static inline struct pglist_data *lruvec #endif } -extern unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru); +extern unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone_idx); #ifdef CONFIG_HAVE_MEMORY_PRESENT void memory_present(int nid, unsigned long start, unsigned long end); --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -234,22 +234,39 @@ bool pgdat_reclaimable(struct pglist_dat pgdat_reclaimable_pages(pgdat) * 6; } -unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru) +/** + * lruvec_lru_size - Returns the number of pages on the given LRU list. + * @lruvec: lru vector + * @lru: lru to use + * @zone_idx: zones to consider (use MAX_NR_ZONES for the whole LRU list) + */ +unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone_idx) { + unsigned long lru_size; + int zid; + if (!mem_cgroup_disabled()) - return mem_cgroup_get_lru_size(lruvec, lru); + lru_size = mem_cgroup_get_lru_size(lruvec, lru); + else + lru_size = node_page_state(lruvec_pgdat(lruvec), NR_LRU_BASE + lru); - return node_page_state(lruvec_pgdat(lruvec), NR_LRU_BASE + lru); -} + for (zid = zone_idx + 1; zid < MAX_NR_ZONES; zid++) { + struct zone *zone = &lruvec_pgdat(lruvec)->node_zones[zid]; + unsigned long size; -unsigned long lruvec_zone_lru_size(struct lruvec *lruvec, enum lru_list lru, - int zone_idx) -{ - if (!mem_cgroup_disabled()) - return mem_cgroup_get_zone_lru_size(lruvec, lru, zone_idx); + if (!managed_zone(zone)) + continue; + + if (!mem_cgroup_disabled()) + size = mem_cgroup_get_zone_lru_size(lruvec, lru, zid); + else + size = zone_page_state(&lruvec_pgdat(lruvec)->node_zones[zid], + NR_ZONE_LRU_BASE + lru); + lru_size -= min(size, lru_size); + } + + return lru_size; - return zone_page_state(&lruvec_pgdat(lruvec)->node_zones[zone_idx], - NR_ZONE_LRU_BASE + lru); } /* @@ -2028,11 +2045,10 @@ static bool inactive_list_is_low(struct struct scan_control *sc) { unsigned long inactive_ratio; - unsigned long inactive; - unsigned long active; + unsigned long inactive, active; + enum lru_list inactive_lru = file * LRU_FILE; + enum lru_list active_lru = file * LRU_FILE + LRU_ACTIVE; unsigned long gb; - struct pglist_data *pgdat = lruvec_pgdat(lruvec); - int zid; /* * If we don't have swap space, anonymous page deactivation @@ -2041,27 +2057,8 @@ static bool inactive_list_is_low(struct if (!file && !total_swap_pages) return false; - inactive = lruvec_lru_size(lruvec, file * LRU_FILE); - active = lruvec_lru_size(lruvec, file * LRU_FILE + LRU_ACTIVE); - - /* - * For zone-constrained allocations, it is necessary to check if - * deactivations are required for lowmem to be reclaimed. This - * calculates the inactive/active pages available in eligible zones. - */ - for (zid = sc->reclaim_idx + 1; zid < MAX_NR_ZONES; zid++) { - struct zone *zone = &pgdat->node_zones[zid]; - unsigned long inactive_zone, active_zone; - - if (!managed_zone(zone)) - continue; - - inactive_zone = lruvec_zone_lru_size(lruvec, file * LRU_FILE, zid); - active_zone = lruvec_zone_lru_size(lruvec, (file * LRU_FILE) + LRU_ACTIVE, zid); - - inactive -= min(inactive, inactive_zone); - active -= min(active, active_zone); - } + inactive = lruvec_lru_size(lruvec, inactive_lru, sc->reclaim_idx); + active = lruvec_lru_size(lruvec, active_lru, sc->reclaim_idx); gb = (inactive + active) >> (30 - PAGE_SHIFT); if (gb) @@ -2208,7 +2205,7 @@ static void get_scan_count(struct lruvec * system is under heavy pressure. */ if (!inactive_list_is_low(lruvec, true, sc) && - lruvec_lru_size(lruvec, LRU_INACTIVE_FILE) >> sc->priority) { + lruvec_lru_size(lruvec, LRU_INACTIVE_FILE, MAX_NR_ZONES) >> sc->priority) { scan_balance = SCAN_FILE; goto out; } @@ -2234,10 +2231,10 @@ static void get_scan_count(struct lruvec * anon in [0], file in [1] */ - anon = lruvec_lru_size(lruvec, LRU_ACTIVE_ANON) + - lruvec_lru_size(lruvec, LRU_INACTIVE_ANON); - file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE) + - lruvec_lru_size(lruvec, LRU_INACTIVE_FILE); + anon = lruvec_lru_size(lruvec, LRU_ACTIVE_ANON, MAX_NR_ZONES) + + lruvec_lru_size(lruvec, LRU_INACTIVE_ANON, MAX_NR_ZONES); + file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE, MAX_NR_ZONES) + + lruvec_lru_size(lruvec, LRU_INACTIVE_FILE, MAX_NR_ZONES); spin_lock_irq(&pgdat->lru_lock); if (unlikely(reclaim_stat->recent_scanned[0] > anon / 4)) { @@ -2275,7 +2272,7 @@ out: unsigned long size; unsigned long scan; - size = lruvec_lru_size(lruvec, lru); + size = lruvec_lru_size(lruvec, lru, MAX_NR_ZONES); scan = size >> sc->priority; if (!scan && pass && force_scan) --- a/mm/workingset.c +++ b/mm/workingset.c @@ -266,7 +266,7 @@ bool workingset_refault(void *shadow) } lruvec = mem_cgroup_lruvec(pgdat, memcg); refault = atomic_long_read(&lruvec->inactive_age); - active_file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE); + active_file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE, MAX_NR_ZONES); rcu_read_unlock(); /* Patches currently in stable-queue which might be from mhocko@xxxxxxxx are queue-4.9/mm-vmpressure-fix-sending-wrong-events-on-underflow.patch queue-4.9/mm-page_alloc-fix-nodes-for-reclaim-in-fast-path.patch queue-4.9/mm-vmscan-consider-eligible-zones-in-get_scan_count.patch queue-4.9/mm-vmscan-cleanup-lru-size-claculations.patch queue-4.9/mm-devm_memremap_pages-hold-device_hotplug-lock-over-mem_hotplug_-begin-done.patch queue-4.9/mm-do-not-access-page-mapping-directly-on-page_endio.patch