[PATCH 19/27] mm: Move vmscan writes and file write accounting to the node

Mel Gorman
2016-04-15T09:17:04Z

As reclaim is now node-based, it follows that page write activity
due to page reclaim should also be accounted for on the node. For
consistency, also account page writes and page dirtying on a per-node
basis.

After this patch, there are a few remaining zone counters that may
appear strange but are fine. NUMA stats are still per-zone as this is a
user-space interface that tools consume. NR_MLOCK, NR_SLAB_*, NR_PAGETABLE,
NR_KERNEL_STACK and NR_BOUNCE are all allocations that potentially pin
low memory and cannot trivially be reclaimed on demand. This information
is still useful for debugging a page allocation failure warning.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
---
include/linux/mmzone.h | 8 ++++----
include/trace/events/writeback.h | 4 ++--
mm/page-writeback.c | 6 +++---
mm/vmscan.c | 4 ++--
mm/vmstat.c | 8 ++++----
5 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 86e16ba69a88..8ffe0208d9c7 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -118,10 +118,6 @@ enum zone_stat_item {
NR_KERNEL_STACK,
/* Second 128 byte cacheline */
NR_BOUNCE,
- NR_VMSCAN_WRITE,
- NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
- NR_DIRTIED, /* page dirtyings since bootup */
- NR_WRITTEN, /* page writings since bootup */
#ifdef CONFIG_NUMA
NUMA_HIT, /* allocated in intended node */
NUMA_MISS, /* allocated in non intended node */
@@ -156,6 +152,10 @@ enum node_stat_item {
NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
NR_UNSTABLE_NFS, /* NFS unstable pages */
+ NR_VMSCAN_WRITE,
+ NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
+ NR_DIRTIED, /* page dirtyings since bootup */
+ NR_WRITTEN, /* page writings since bootup */
NR_VM_NODE_STAT_ITEMS
};

diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index c581d9c04ca5..a1002cfede1d 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -415,8 +415,8 @@ TRACE_EVENT(global_dirty_state,
__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->nr_dirtied = global_node_page_state(NR_DIRTIED);
+ __entry->nr_written = global_node_page_state(NR_WRITTEN);
__entry->background_thresh = background_thresh;
__entry->dirty_thresh = dirty_thresh;
__entry->dirty_limit = global_wb_domain.dirty_limit;
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 3ffb15f45a8b..76bc0aa3ef4e 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2429,7 +2429,7 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)

mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_DIRTY);
__inc_node_page_state(page, NR_FILE_DIRTY);
- __inc_zone_page_state(page, NR_DIRTIED);
+ __inc_node_page_state(page, NR_DIRTIED);
__inc_wb_stat(wb, WB_RECLAIMABLE);
__inc_wb_stat(wb, WB_DIRTIED);
task_io_account_write(PAGE_SIZE);
@@ -2517,7 +2517,7 @@ void account_page_redirty(struct page *page)

wb = unlocked_inode_to_wb_begin(inode, &locked);
current->nr_dirtied--;
- dec_zone_page_state(page, NR_DIRTIED);
+ dec_node_page_state(page, NR_DIRTIED);
dec_wb_stat(wb, WB_DIRTIED);
unlocked_inode_to_wb_end(inode, locked);
}
@@ -2746,7 +2746,7 @@ int test_clear_page_writeback(struct page *page)
if (ret) {
mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_WRITEBACK);
dec_node_page_state(page, NR_WRITEBACK);
- inc_zone_page_state(page, NR_WRITTEN);
+ inc_node_page_state(page, NR_WRITTEN);
}
unlock_page_memcg(page);
return ret;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b847f1a32ac0..e2238ab6ae53 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -596,7 +596,7 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
ClearPageReclaim(page);
}
trace_mm_vmscan_writepage(page);
- inc_zone_page_state(page, NR_VMSCAN_WRITE);
+ inc_node_page_state(page, NR_VMSCAN_WRITE);
return PAGE_SUCCESS;
}

@@ -1095,7 +1095,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
* except we already have the page isolated
* and know it's dirty
*/
- inc_zone_page_state(page, NR_VMSCAN_IMMEDIATE);
+ inc_node_page_state(page, NR_VMSCAN_IMMEDIATE);
SetPageReclaim(page);

goto keep_locked;
diff --git a/mm/vmstat.c b/mm/vmstat.c
index b282847d7725..c42ab4d9fa2b 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -921,10 +921,6 @@ const char * const vmstat_text[] = {
"nr_page_table_pages",
"nr_kernel_stack",
"nr_bounce",
- "nr_vmscan_write",
- "nr_vmscan_immediate_reclaim",
- "nr_dirtied",
- "nr_written",

#ifdef CONFIG_NUMA
"numa_hit",
@@ -957,6 +953,10 @@ const char * const vmstat_text[] = {
"nr_writeback_temp",
"nr_shmem",
"nr_unstable",
+ "nr_vmscan_write",
+ "nr_vmscan_immediate_reclaim",
+ "nr_dirtied",
+ "nr_written",

/* enum writeback_stat_item counters */
"nr_dirty_threshold",
--
2.6.4