[lkml]   [2011]   [Jan]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH 3/7] [v2] zram/xvmalloc: free bit block insertion optimization
This change is in a conditional block which is entered only when there is
an existing data block on the freelist where the insert has taken place.

The new block is pushed onto the freelist stack and this conditional block
is updating links in the prior stack head to point to the new stack head.
After this conditional block the first-/second-level indices are updated
to indicate that there is a free block at this location.

This patch adds an immediate return from the conditional block to avoid
setting bits again to indicate a free block on this freelist. The bits
would already be set because there was an existing free block on this

Signed-off-by: Robert Jennings <>
drivers/staging/zram/xvmalloc.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/zram/xvmalloc.c b/drivers/staging/zram/xvmalloc.c
index b644067..149138a 100644
--- a/drivers/staging/zram/xvmalloc.c
+++ b/drivers/staging/zram/xvmalloc.c
@@ -200,6 +200,8 @@ static void insert_block(struct xv_pool *pool, struct page *page, u32 offset,
nextblock->link.prev_page = page;
nextblock->link.prev_offset = offset;
put_ptr_atomic(nextblock, KM_USER1);
+ /* If there was a next page then the free bits are set. */
+ return;

__set_bit(slindex % BITS_PER_LONG, &pool->slbitmap[flindex]);

 \ /
  Last update: 2011-01-28 16:01    [W:0.100 / U:15.008 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site