From d507e2ebd2c7be9138e5cf5c0cb1931c90c42ab1 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Thu, 10 Aug 2017 15:23:31 -0700 Subject: mm: fix global NR_SLAB_.*CLAIMABLE counter reads As Tetsuo points out: "Commit 385386cff4c6 ("mm: vmstat: move slab statistics from zone to node counters") broke "Slab:" field of /proc/meminfo . It shows nearly 0kB" In addition to /proc/meminfo, this problem also affects the slab counters OOM/allocation failure info dumps, can cause early -ENOMEM from overcommit protection, and miscalculate image size requirements during suspend-to-disk. This is because the patch in question switched the slab counters from the zone level to the node level, but forgot to update the global accessor functions to read the aggregate node data instead of the aggregate zone data. Use global_node_page_state() to access the global slab counters. Fixes: 385386cff4c6 ("mm: vmstat: move slab statistics from zone to node counters") Link: http://lkml.kernel.org/r/20170801134256.5400-1-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Reported-by: Tetsuo Handa Acked-by: Michal Hocko Cc: Josef Bacik Cc: Vladimir Davydov Cc: Stefan Agner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 9 +++++---- mm/util.c | 2 +- 2 files changed, 6 insertions(+), 5 deletions(-) (limited to 'mm') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fc32aa81f359..626a430e32d1 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4458,8 +4458,9 @@ long si_mem_available(void) * Part of the reclaimable slab consists of items that are in use, * and cannot be freed. Cap this estimate at the low watermark. */ - available += global_page_state(NR_SLAB_RECLAIMABLE) - - min(global_page_state(NR_SLAB_RECLAIMABLE) / 2, wmark_low); + available += global_node_page_state(NR_SLAB_RECLAIMABLE) - + min(global_node_page_state(NR_SLAB_RECLAIMABLE) / 2, + wmark_low); if (available < 0) available = 0; @@ -4602,8 +4603,8 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask) global_node_page_state(NR_FILE_DIRTY), global_node_page_state(NR_WRITEBACK), global_node_page_state(NR_UNSTABLE_NFS), - global_page_state(NR_SLAB_RECLAIMABLE), - global_page_state(NR_SLAB_UNRECLAIMABLE), + global_node_page_state(NR_SLAB_RECLAIMABLE), + global_node_page_state(NR_SLAB_UNRECLAIMABLE), global_node_page_state(NR_FILE_MAPPED), global_node_page_state(NR_SHMEM), global_page_state(NR_PAGETABLE), diff --git a/mm/util.c b/mm/util.c index 7b07ec852e01..9ecddf568fe3 100644 --- a/mm/util.c +++ b/mm/util.c @@ -633,7 +633,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) * which are reclaimable, under pressure. The dentry * cache and most inode caches should fall into this */ - free += global_page_state(NR_SLAB_RECLAIMABLE); + free += global_node_page_state(NR_SLAB_RECLAIMABLE); /* * Leave reserved pages. The pages are not for anonymous pages. -- cgit v1.2.3