[PATCH] zoned vm counters: convert nr_mapped to per zone counter

nr_mapped is important because it allows a determination of how many pages of
a zone are not mapped, which would allow a more efficient means of determining
when we need to reclaim memory in a zone.

We take the nr_mapped field out of the page state structure and define a new
per zone counter named NR_FILE_MAPPED (the anonymous pages will be split off
from NR_MAPPED in the next patch).

We replace the use of nr_mapped in various kernel locations.  This avoids the
looping over all processors in try_to_free_pages(), writeback, reclaim (swap +
zone reclaim).

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 210f9bbbb04f..4800091c129a 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -401,13 +401,13 @@ struct seq_operations fragmentation_op = {
 
 static char *vmstat_text[] = {
         /* Zoned VM counters */
+        "nr_mapped",
 
         /* Page state */
         "nr_dirty",
         "nr_writeback",
         "nr_unstable",
         "nr_page_table_pages",
-        "nr_mapped",
         "nr_slab",
 
         "pgpgin",