[PATCH 5/7] Remove redundant check for zero page

From: Nitin Gupta
Date: Thu Jan 28 2010 - 10:46:38 EST


ramzswap_free_page() already handles the case for zero filled
pages. So, remove redundant logic for the same in ramzswap_write().

Signed-off-by: Nitin Gupta <ngupta@xxxxxxxxxx>
---
drivers/staging/ramzswap/ramzswap_drv.c | 15 +++++----------
1 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/ramzswap/ramzswap_drv.c b/drivers/staging/ramzswap/ramzswap_drv.c
index 3035add..7e0a3fa 100644
--- a/drivers/staging/ramzswap/ramzswap_drv.c
+++ b/drivers/staging/ramzswap/ramzswap_drv.c
@@ -593,6 +593,10 @@ static void ramzswap_free_page(struct ramzswap *rzs, size_t index)
u32 offset = rzs->table[index].offset;

if (unlikely(!page)) {
+ /*
+ * No memory is allocated for zero filled pages.
+ * Simply clear zero page flag.
+ */
if (rzs_test_flag(rzs, index, RZS_ZERO)) {
rzs_clear_flag(rzs, index, RZS_ZERO);
rzs_stat_dec(&rzs->stats.pages_zero);
@@ -789,18 +793,9 @@ static int ramzswap_write(struct ramzswap *rzs, struct bio *bio)
* is no longer referenced by any process. So, its now safe
* to free the memory that was allocated for this page.
*/
- if (rzs->table[index].page)
+ if (rzs->table[index].page || rzs_test_flag(rzs, index, RZS_ZERO))
ramzswap_free_page(rzs, index);

- /*
- * No memory is allocated for zero filled pages.
- * Simply clear zero page flag.
- */
- if (rzs_test_flag(rzs, index, RZS_ZERO)) {
- rzs_stat_dec(&rzs->stats.pages_zero);
- rzs_clear_flag(rzs, index, RZS_ZERO);
- }
-
mutex_lock(&rzs->lock);

user_mem = kmap_atomic(page, KM_USER0);
--
1.6.2.5

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