mm: move most file-based accounting to the node

There are now a number of accounting oddities such as mapped file pages
being accounted for on the node while the total number of file pages are
accounted on the zone.  This can be coped with to some extent but it's
confusing so this patch moves the relevant file-based accounted.  Due to
throttling logic in the page allocator for reliable OOM detection, it is
still necessary to track dirty and writeback pages on a per-zone basis.

[mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting]
  Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net
Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 13 insertions, 12 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 2d4a8804eafa..acd4665c3025 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -114,21 +114,16 @@ enum zone_stat_item {
 	NR_ZONE_LRU_BASE, /* Used only for compaction and reclaim retry */
 	NR_ZONE_LRU_ANON = NR_ZONE_LRU_BASE,
 	NR_ZONE_LRU_FILE,
+	NR_ZONE_WRITE_PENDING,	/* Count of dirty, writeback and unstable pages */
 	NR_MLOCK,		/* mlock()ed pages found and moved off LRU */
-	NR_FILE_PAGES,
-	NR_FILE_DIRTY,
-	NR_WRITEBACK,
 	NR_SLAB_RECLAIMABLE,
 	NR_SLAB_UNRECLAIMABLE,
 	NR_PAGETABLE,		/* used for pagetables */
 	NR_KERNEL_STACK,
 	/* Second 128 byte cacheline */
-	NR_UNSTABLE_NFS,	/* NFS unstable pages */
 	NR_BOUNCE,
 	NR_VMSCAN_WRITE,
 	NR_VMSCAN_IMMEDIATE,	/* Prioritise for reclaim when writeback ends */
-	NR_WRITEBACK_TEMP,	/* Writeback using temporary buffers */
-	NR_SHMEM,		/* shmem pages (included tmpfs/GEM pages) */
 	NR_DIRTIED,		/* page dirtyings since bootup */
 	NR_WRITTEN,		/* page writings since bootup */
 #if IS_ENABLED(CONFIG_ZSMALLOC)
@@ -142,9 +137,6 @@ enum zone_stat_item {
 	NUMA_LOCAL,		/* allocation from local node */
 	NUMA_OTHER,		/* allocation from other node */
 #endif
-	NR_ANON_THPS,
-	NR_SHMEM_THPS,
-	NR_SHMEM_PMDMAPPED,
 	NR_FREE_CMA_PAGES,
 	NR_VM_ZONE_STAT_ITEMS };
 
@@ -164,6 +156,15 @@ enum node_stat_item {
 	NR_ANON_MAPPED,	/* Mapped anonymous pages */
 	NR_FILE_MAPPED,	/* pagecache pages mapped into pagetables.
 			   only modified from process context */
+	NR_FILE_PAGES,
+	NR_FILE_DIRTY,
+	NR_WRITEBACK,
+	NR_WRITEBACK_TEMP,	/* Writeback using temporary buffers */
+	NR_SHMEM,		/* shmem pages (included tmpfs/GEM pages) */
+	NR_SHMEM_THPS,
+	NR_SHMEM_PMDMAPPED,
+	NR_ANON_THPS,
+	NR_UNSTABLE_NFS,	/* NFS unstable pages */
 	NR_VM_NODE_STAT_ITEMS
 };
 
diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index 531f5811ff6b..ad20f2d2b1f9 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -412,9 +412,9 @@ TRACE_EVENT(global_dirty_state,
 	),
 
 	TP_fast_assign(
-		__entry->nr_dirty	= global_page_state(NR_FILE_DIRTY);
-		__entry->nr_writeback	= global_page_state(NR_WRITEBACK);
-		__entry->nr_unstable	= global_page_state(NR_UNSTABLE_NFS);
+		__entry->nr_dirty	= global_node_page_state(NR_FILE_DIRTY);
+		__entry->nr_writeback	= global_node_page_state(NR_WRITEBACK);
+		__entry->nr_unstable	= global_node_page_state(NR_UNSTABLE_NFS);
 		__entry->nr_dirtied	= global_page_state(NR_DIRTIED);
 		__entry->nr_written	= global_page_state(NR_WRITTEN);
 		__entry->background_thresh = background_thresh;