[PATCH 5/5] add shmem vmstat

From: KOSAKI Motohiro
Date: Thu Jul 09 2009 - 04:18:19 EST


ChangeLog
Since v1
- Fixed misaccounting bug on page migration

========================
Subject: [PATCH] add shmem vmstat

Recently, We faced several OOM problem by plenty GEM cache. and generally,
plenty Shmem/Tmpfs potentially makes memory shortage problem.

We often use following calculation to know shmem pages,
shmem = NR_ACTIVE_ANON + NR_INACTIVE_ANON - NR_ANON_PAGES
but it is wrong expression. it doesn't consider isolated page and
mlocked page.

Then, This patch make explicit Shmem/Tmpfs vm-stat accounting.


Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
---
drivers/base/node.c | 2 ++
fs/proc/meminfo.c | 2 ++
include/linux/mmzone.h | 1 +
mm/filemap.c | 4 ++++
mm/migrate.c | 4 ++++
mm/page_alloc.c | 5 ++++-
mm/vmstat.c | 1 +
7 files changed, 18 insertions(+), 1 deletion(-)

Index: b/drivers/base/node.c
===================================================================
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -87,6 +87,7 @@ static ssize_t node_read_meminfo(struct
"Node %d FilePages: %8lu kB\n"
"Node %d Mapped: %8lu kB\n"
"Node %d AnonPages: %8lu kB\n"
+ "Node %d Shmem: %8lu kB\n"
"Node %d KernelStack: %8lu kB\n"
"Node %d PageTables: %8lu kB\n"
"Node %d NFS_Unstable: %8lu kB\n"
@@ -121,6 +122,7 @@ static ssize_t node_read_meminfo(struct
nid, K(node_page_state(nid, NR_FILE_PAGES)),
nid, K(node_page_state(nid, NR_FILE_MAPPED)),
nid, K(node_page_state(nid, NR_ANON_PAGES)),
+ nid, K(node_page_state(nid, NR_SHMEM)),
nid, node_page_state(nid, NR_KERNEL_STACK) *
THREAD_SIZE / 1024,
nid, K(node_page_state(nid, NR_PAGETABLE)),
Index: b/fs/proc/meminfo.c
===================================================================
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -83,6 +83,7 @@ static int meminfo_proc_show(struct seq_
"Writeback: %8lu kB\n"
"AnonPages: %8lu kB\n"
"Mapped: %8lu kB\n"
+ "Shmem: %8lu kB\n"
"Slab: %8lu kB\n"
"SReclaimable: %8lu kB\n"
"SUnreclaim: %8lu kB\n"
@@ -129,6 +130,7 @@ static int meminfo_proc_show(struct seq_
K(global_page_state(NR_WRITEBACK)),
K(global_page_state(NR_ANON_PAGES)),
K(global_page_state(NR_FILE_MAPPED)),
+ K(global_page_state(NR_SHMEM)),
K(global_page_state(NR_SLAB_RECLAIMABLE) +
global_page_state(NR_SLAB_UNRECLAIMABLE)),
K(global_page_state(NR_SLAB_RECLAIMABLE)),
Index: b/include/linux/mmzone.h
===================================================================
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -102,6 +102,7 @@ enum zone_stat_item {
NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
+ NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
#ifdef CONFIG_NUMA
NUMA_HIT, /* allocated in intended node */
NUMA_MISS, /* allocated in non intended node */
Index: b/mm/filemap.c
===================================================================
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -120,6 +120,8 @@ void __remove_from_page_cache(struct pag
page->mapping = NULL;
mapping->nrpages--;
__dec_zone_page_state(page, NR_FILE_PAGES);
+ if (PageSwapBacked(page))
+ __dec_zone_page_state(page, NR_SHMEM);
BUG_ON(page_mapped(page));

/*
@@ -476,6 +478,8 @@ int add_to_page_cache_locked(struct page
if (likely(!error)) {
mapping->nrpages++;
__inc_zone_page_state(page, NR_FILE_PAGES);
+ if (PageSwapBacked(page))
+ __inc_zone_page_state(page, NR_SHMEM);
spin_unlock_irq(&mapping->tree_lock);
} else {
page->mapping = NULL;
Index: b/mm/vmstat.c
===================================================================
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -646,6 +646,7 @@ static const char * const vmstat_text[]
"nr_writeback_temp",
"nr_isolated_anon",
"nr_isolated_file",
+ "nr_shmem",
#ifdef CONFIG_NUMA
"numa_hit",
"numa_miss",
Index: b/mm/page_alloc.c
===================================================================
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2120,7 +2120,7 @@ void show_free_areas(void)
" unevictable:%lu\n"
" dirty:%lu writeback:%lu unstable:%lu buffer:%lu\n"
" free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
- " mapped:%lu pagetables:%lu bounce:%lu\n",
+ " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
global_page_state(NR_ACTIVE_ANON),
global_page_state(NR_INACTIVE_ANON),
global_page_state(NR_ISOLATED_ANON),
@@ -2136,6 +2136,7 @@ void show_free_areas(void)
global_page_state(NR_SLAB_RECLAIMABLE),
global_page_state(NR_SLAB_UNRECLAIMABLE),
global_page_state(NR_FILE_MAPPED),
+ global_page_state(NR_SHMEM),
global_page_state(NR_PAGETABLE),
global_page_state(NR_BOUNCE));

@@ -2160,6 +2161,7 @@ void show_free_areas(void)
" dirty:%lukB"
" writeback:%lukB"
" mapped:%lukB"
+ " shmem:%lukB"
" slab_reclaimable:%lukB"
" slab_unreclaimable:%lukB"
" kernel_stack:%lukB"
@@ -2187,6 +2189,7 @@ void show_free_areas(void)
K(zone_page_state(zone, NR_FILE_DIRTY)),
K(zone_page_state(zone, NR_WRITEBACK)),
K(zone_page_state(zone, NR_FILE_MAPPED)),
+ K(zone_page_state(zone, NR_SHMEM)),
K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
zone_page_state(zone, NR_KERNEL_STACK) *
Index: b/mm/migrate.c
===================================================================
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -312,7 +312,11 @@ static int migrate_page_move_mapping(str
*/
__dec_zone_page_state(page, NR_FILE_PAGES);
__inc_zone_page_state(newpage, NR_FILE_PAGES);
+ if (PageSwapBacked(page)) {
+ __dec_zone_page_state(page, NR_SHMEM);
+ __inc_zone_page_state(newpage, NR_SHMEM);

+ }
spin_unlock_irq(&mapping->tree_lock);

return 0;


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/