From f3dbd34460ff54962d3e3244b6bcb7f5295356e6 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Fri, 30 Jun 2006 01:55:36 -0700 Subject: [PATCH] [PATCH] zoned vm counters: split NR_ANON_PAGES off from NR_FILE_MAPPED The current NR_FILE_MAPPED is used by zone reclaim and the dirty load calculation as the number of mapped pagecache pages. However, that is not true. NR_FILE_MAPPED includes the mapped anonymous pages. This patch separates those and therefore allows an accurate tracking of the anonymous pages per zone. It then becomes possible to determine the number of unmapped pages per zone and we can avoid scanning for unmapped pages if there are none. Also it may now be possible to determine the mapped/unmapped ratio in get_dirty_limit. Isnt the number of anonymous pages irrelevant in that calculation? Note that this will change the meaning of the number of mapped pages reported in /proc/vmstat /proc/meminfo and in the per node statistics. This may affect user space tools that monitor these counters! NR_FILE_MAPPED works like NR_FILE_DIRTY. It is only valid for pagecache pages. Signed-off-by: Christoph Lameter Cc: Trond Myklebust Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/base/node.c | 2 ++ fs/proc/proc_misc.c | 2 ++ include/linux/mmzone.h | 3 ++- mm/page-writeback.c | 3 ++- mm/rmap.c | 5 +++-- mm/vmscan.c | 3 ++- mm/vmstat.c | 1 + 7 files changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index ae9e3fea4b31..c3bf05158c6d 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -71,6 +71,7 @@ static ssize_t node_read_meminfo(struct sys_device * dev, char * buf) "Node %d Writeback: %8lu kB\n" "Node %d FilePages: %8lu kB\n" "Node %d Mapped: %8lu kB\n" + "Node %d AnonPages: %8lu kB\n" "Node %d Slab: %8lu kB\n", nid, K(i.totalram), nid, K(i.freeram), @@ -85,6 +86,7 @@ static ssize_t node_read_meminfo(struct sys_device * dev, char * buf) nid, K(ps.nr_writeback), 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(ps.nr_slab)); n += hugetlb_report_node_meminfo(nid, buf + n); return n; diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c index 1af12fd77fe6..ff809656ce31 100644 --- a/fs/proc/proc_misc.c +++ b/fs/proc/proc_misc.c @@ -168,6 +168,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off, "SwapFree: %8lu kB\n" "Dirty: %8lu kB\n" "Writeback: %8lu kB\n" + "AnonPages: %8lu kB\n" "Mapped: %8lu kB\n" "Slab: %8lu kB\n" "CommitLimit: %8lu kB\n" @@ -191,6 +192,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off, K(i.freeswap), K(ps.nr_dirty), K(ps.nr_writeback), + K(global_page_state(NR_ANON_PAGES)), K(global_page_state(NR_FILE_MAPPED)), K(ps.nr_slab), K(allowed), diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 08be91e6cecf..4833abd4458b 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -47,7 +47,8 @@ struct zone_padding { #endif enum zone_stat_item { - NR_FILE_MAPPED, /* mapped into pagetables. + NR_ANON_PAGES, /* Mapped anonymous pages */ + NR_FILE_MAPPED, /* pagecache pages mapped into pagetables. only modified from process context */ NR_FILE_PAGES, NR_VM_ZONE_STAT_ITEMS }; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 60c7244c42e4..0faacfe18909 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -111,7 +111,8 @@ static void get_writeback_state(struct writeback_state *wbs) { wbs->nr_dirty = read_page_state(nr_dirty); wbs->nr_unstable = read_page_state(nr_unstable); - wbs->nr_mapped = global_page_state(NR_FILE_MAPPED); + wbs->nr_mapped = global_page_state(NR_FILE_MAPPED) + + global_page_state(NR_ANON_PAGES); wbs->nr_writeback = read_page_state(nr_writeback); } diff --git a/mm/rmap.c b/mm/rmap.c index af5e9808e65d..40158b59729e 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -455,7 +455,7 @@ static void __page_set_anon_rmap(struct page *page, * nr_mapped state can be updated without turning off * interrupts because it is not modified via interrupt. */ - __inc_zone_page_state(page, NR_FILE_MAPPED); + __inc_zone_page_state(page, NR_ANON_PAGES); } /** @@ -531,7 +531,8 @@ void page_remove_rmap(struct page *page) */ if (page_test_and_clear_dirty(page)) set_page_dirty(page); - __dec_zone_page_state(page, NR_FILE_MAPPED); + __dec_zone_page_state(page, + PageAnon(page) ? NR_ANON_PAGES : NR_FILE_MAPPED); } } diff --git a/mm/vmscan.c b/mm/vmscan.c index 08bc54e80862..2f0390161c0e 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -742,7 +742,8 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, * how much memory * is mapped. */ - mapped_ratio = (global_page_state(NR_FILE_MAPPED) * 100) / + mapped_ratio = ((global_page_state(NR_FILE_MAPPED) + + global_page_state(NR_ANON_PAGES)) * 100) / vm_total_pages; /* diff --git a/mm/vmstat.c b/mm/vmstat.c index f16b33eb6d5c..3baf4dffa62a 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -395,6 +395,7 @@ struct seq_operations fragmentation_op = { static char *vmstat_text[] = { /* Zoned VM counters */ + "nr_anon_pages", "nr_mapped", "nr_file_pages",