vmstat: mlocked pages statistics

Add NR_MLOCK zone page state, which provides a (conservative) count of
mlocked pages (actually, the number of mlocked pages moved off the LRU).

Reworked by lts to fit in with the modified mlock page support in the
Reclaim Scalability series.

[kosaki.motohiro@jp.fujitsu.com: fix incorrect Mlocked field of /proc/meminfo]
[lee.schermerhorn@hp.com: mlocked-pages: add event counting with statistics]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 6dd60eaea997..61b25f4eabe6 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -176,6 +176,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off,
                 "Inactive(file): %8lu kB\n"
 #ifdef CONFIG_UNEVICTABLE_LRU
                 "Unevictable:    %8lu kB\n"
+                "Mlocked:        %8lu kB\n"
 #endif
 #ifdef CONFIG_HIGHMEM
                 "HighTotal:      %8lu kB\n"
@@ -217,6 +218,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off,
                 K(pages[LRU_INACTIVE_FILE]),
 #ifdef CONFIG_UNEVICTABLE_LRU
                 K(pages[LRU_UNEVICTABLE]),
+                K(global_page_state(NR_MLOCK)),
 #endif
 #ifdef CONFIG_HIGHMEM
                 K(i.totalhigh),