staging: zcache: handle zcache_[eph|pers]_zpages for zero-filled page
Increment/decrement zcache_[eph|pers]_zpages for zero-filled pages,
the main point of the counters for zpages and pageframes is to be
able to calculate density == zpages/pageframes. A zero-filled page
becomes a zpage that "compresses" to zero bytes and, as a result,
requires zero pageframes for storage. So the zpages counter should
be increased but the pageframes counter should not.
[Dan Magenheimer <dan.magenheimer@oracle.com>: patch description]
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c
index 927d5fd..1994cab 100644
--- a/drivers/staging/zcache/zcache-main.c
+++ b/drivers/staging/zcache/zcache-main.c
@@ -648,6 +648,8 @@
if (pampd == (void *)ZERO_FILLED) {
handle_zero_filled_page(data);
zero_filled = true;
+ zsize = 0;
+ zpages = 1;
if (!raw)
*sizep = PAGE_SIZE;
goto zero_fill;
@@ -696,8 +698,11 @@
BUG_ON(preemptible());
- if (pampd == (void *)ZERO_FILLED)
+ if (pampd == (void *)ZERO_FILLED) {
zero_filled = true;
+ zsize = 0;
+ zpages = 1;
+ }
if (pampd_is_remote(pampd) && !zero_filled) {
BUG_ON(!ramster_enabled);