From 1426d1f8d93d9a4eea97c91eb5ebd1357afe7b16 Mon Sep 17 00:00:00 2001 From: Liam Mark Date: Fri, 27 Feb 2015 12:59:00 -0800 Subject: [PATCH] lowmemorykiller: Don't count swap cache pages twice The lowmem_shrink function discounts all the swap cache pages from the file cache count. The zone aware code also discounts all file cache pages from a certain zone. This results in some swap cache pages being discounted twice, which can result in the low memory killer being unnecessarily aggressive. Fix the low memory killer to only discount the swap cache pages once. Change-Id: I650bbfbf0fbbabd01d82bdb3502b57ff59c3e14f Signed-off-by: Liam Mark Signed-off-by: Vinayak Menon --- drivers/staging/android/lowmemorykiller.c | 3 ++- include/linux/mmzone.h | 1 + mm/swap_state.c | 2 ++ mm/vmstat.c | 1 + 4 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/staging/android/lowmemorykiller.c b/drivers/staging/android/lowmemorykiller.c index e60421299164..1aab1f67e571 100644 --- a/drivers/staging/android/lowmemorykiller.c +++ b/drivers/staging/android/lowmemorykiller.c @@ -251,7 +251,8 @@ void tune_lmk_zone_param(struct zonelist *zonelist, int classzone_idx, if (other_file != NULL) *other_file -= zone_page_state(zone, NR_FILE_PAGES) - - zone_page_state(zone, NR_SHMEM); + - zone_page_state(zone, NR_SHMEM) + - zone_page_state(zone, NR_SWAPCACHE); } else if (zone_idx < classzone_idx) { if (zone_watermark_ok(zone, 0, 0, classzone_idx, 0) && other_free) { diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 8a5894308eb2..04030f756e7c 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -167,6 +167,7 @@ enum zone_stat_item { WORKINGSET_NODERECLAIM, NR_ANON_TRANSPARENT_HUGEPAGES, NR_FREE_CMA_PAGES, + NR_SWAPCACHE, NR_VM_ZONE_STAT_ITEMS }; /* diff --git a/mm/swap_state.c b/mm/swap_state.c index 4e166f1c692c..61039e39e25f 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -96,6 +96,7 @@ int __add_to_swap_cache(struct page *page, swp_entry_t entry) if (likely(!error)) { address_space->nrpages++; __inc_zone_page_state(page, NR_FILE_PAGES); + __inc_zone_page_state(page, NR_SWAPCACHE); INC_CACHE_INFO(add_total); } spin_unlock_irq(&address_space->tree_lock); @@ -148,6 +149,7 @@ void __delete_from_swap_cache(struct page *page) ClearPageSwapCache(page); address_space->nrpages--; __dec_zone_page_state(page, NR_FILE_PAGES); + __dec_zone_page_state(page, NR_SWAPCACHE); INC_CACHE_INFO(del_total); } diff --git a/mm/vmstat.c b/mm/vmstat.c index 4923dfe89983..c0e67319d3e8 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -763,6 +763,7 @@ const char * const vmstat_text[] = { "workingset_nodereclaim", "nr_anon_transparent_hugepages", "nr_free_cma", + "nr_swapcache", /* enum writeback_stat_item counters */ "nr_dirty_threshold",