From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Snitzer Subject: [PATCH 02/24] dm space map disk: optimise sm_disk_dec_block Date: Thu, 24 Oct 2013 14:30:15 -0400 Message-ID: <1382639437-27007-3-git-send-email-snitzer@redhat.com> References: <1382639437-27007-1-git-send-email-snitzer@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1382639437-27007-1-git-send-email-snitzer@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: dm-devel@redhat.com Cc: Morgan Mears , Heinz Mauelshagen , Joe Thornber , Mike Snitzer List-Id: dm-devel.ids From: Joe Thornber Don't waste time spotting blocks that have been allocated and then freed in the same transaction. The extra lookup is expensive, and I don't think it really gives us much. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer --- drivers/md/persistent-data/dm-space-map-disk.c | 18 +----------------- 1 file changed, 1 insertion(+), 17 deletions(-) diff --git a/drivers/md/persistent-data/dm-space-map-disk.c b/drivers/md/persistent-data/dm-space-map-disk.c index e735a6d..cfbf961 100644 --- a/drivers/md/persistent-data/dm-space-map-disk.c +++ b/drivers/md/persistent-data/dm-space-map-disk.c @@ -140,26 +140,10 @@ static int sm_disk_inc_block(struct dm_space_map *sm, dm_block_t b) static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b) { - int r; - uint32_t old_count; enum allocation_event ev; struct sm_disk *smd = container_of(sm, struct sm_disk, sm); - r = sm_ll_dec(&smd->ll, b, &ev); - if (!r && (ev == SM_FREE)) { - /* - * It's only free if it's also free in the last - * transaction. - */ - r = sm_ll_lookup(&smd->old_ll, b, &old_count); - if (r) - return r; - - if (!old_count) - smd->nr_allocated_this_transaction--; - } - - return r; + return sm_ll_dec(&smd->ll, b, &ev); } static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b) -- 1.8.1.4