From mboxrd@z Thu Jan 1 00:00:00 1970 From: Namjae Jeon Subject: [f2fs-dev] [PATCH 2/4] f2fs: reorganise the function get_victim_by_default Date: Sat, 8 Jun 2013 21:25:16 +0900 Message-ID: <1370694316-2772-1-git-send-email-linkinjeon@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1UlID3-0007Yd-HH for linux-f2fs-devel@lists.sourceforge.net; Sat, 08 Jun 2013 12:25:29 +0000 Received: from mail-pd0-f174.google.com ([209.85.192.174]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1UlID2-0007ZG-ND for linux-f2fs-devel@lists.sourceforge.net; Sat, 08 Jun 2013 12:25:29 +0000 Received: by mail-pd0-f174.google.com with SMTP id 10so4844238pdc.19 for ; Sat, 08 Jun 2013 05:25:22 -0700 (PDT) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: jaegeuk.kim@samsung.com Cc: Namjae Jeon , Namjae Jeon , Pankaj Kumar , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net From: Namjae Jeon Fix the function get_victim_by_default, where it checks for the condition that p.min_segno != NULL_SEGNO as shown: if (p.min_segno != NULL_SEGNO) goto got_it; and if above condition is true then got_it: if (p.min_segno != NULL_SEGNO) { So this condition is being checked twice. Hence move the goto statement after the if condition so that duplication of condition check is avoided. Also this function makes a call to get_max_cost() to compute the max cost based on the f2fs_sbi_info and victim policy. Since get_max_cost depends on on three parameters of victim_sel_policy => alloc_mode, gc_mode & ofs_unit, once this victim policy is initialised, these value will not change till the execution time of get_victim_by_default() & also f2fs_sbi_info structure parameters will not change. Hence making calls to get_max_cost() in while loop does not seems to be a good point. Instead we can call it once in begining and store the results in local variable, which later can serve our purpose for comparing the cost with max cost inside the while loop. Signed-off-by: Namjae Jeon Signed-off-by: Pankaj Kumar --- fs/f2fs/gc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index ddc2c67..3a9df36 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -241,14 +241,14 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi, { struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); struct victim_sel_policy p; - unsigned int secno; + unsigned int secno, max_cost; int nsearched = 0; p.alloc_mode = alloc_mode; select_policy(sbi, gc_type, type, &p); p.min_segno = NULL_SEGNO; - p.min_cost = get_max_cost(sbi, &p); + p.min_cost = max_cost = get_max_cost(sbi, &p); mutex_lock(&dirty_i->seglist_lock); @@ -287,7 +287,7 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi, p.min_cost = cost; } - if (cost == get_max_cost(sbi, &p)) + if (cost == max_cost) continue; if (nsearched++ >= MAX_VICTIM_SEARCH) { @@ -295,8 +295,8 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi, break; } } -got_it: if (p.min_segno != NULL_SEGNO) { +got_it: if (p.alloc_mode == LFS) { secno = GET_SECNO(sbi, p.min_segno); if (gc_type == FG_GC) -- 1.7.9.5 ------------------------------------------------------------------------------ How ServiceNow helps IT people transform IT departments: 1. A cloud service to automate IT design, transition and operations 2. Dashboards that offer high-level views of enterprise services 3. A single system of record for all IT processes http://p.sf.net/sfu/servicenow-d2d-j