[PATCH] zoned vm counters: conversion of nr_pagecache to per zone counter

Currently a single atomic variable is used to establish the size of the page
cache in the whole machine.  The zoned VM counters have the same method of
implementation as the nr_pagecache code but also allow the determination of
the pagecache size per zone.

Remove the special implementation for nr_pagecache and make it a zoned counter
named NR_FILE_PAGES.

Updates of the page cache counters are always performed with interrupts off.
We can therefore use the __ variant here.

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, 2 insertions, 1 deletions

diff --git a/arch/s390/appldata/appldata_mem.c b/arch/s390/appldata/appldata_mem.c
index 7915a197d96d..180ba79a6267 100644
--- a/arch/s390/appldata/appldata_mem.c
+++ b/arch/s390/appldata/appldata_mem.c
@@ -130,7 +130,8 @@ static void appldata_get_mem_data(void *data)
 	mem_data->totalhigh = P2K(val.totalhigh);
 	mem_data->freehigh  = P2K(val.freehigh);
 	mem_data->bufferram = P2K(val.bufferram);
-	mem_data->cached    = P2K(atomic_read(&nr_pagecache) - val.bufferram);
+	mem_data->cached    = P2K(global_page_state(NR_FILE_PAGES)
+				- val.bufferram);
 
 	si_swapinfo(&val);
 	mem_data->totalswap = P2K(val.totalswap);