Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753854AbaG3M7Y (ORCPT ); Wed, 30 Jul 2014 08:59:24 -0400 Received: from mailout2.samsung.com ([203.254.224.25]:32045 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752749AbaG3M7V (ORCPT ); Wed, 30 Jul 2014 08:59:21 -0400 X-AuditID: cbfee61b-f79f86d00000144c-c1-53d8ec28efa5 From: Chao Yu To: "'Jaegeuk Kim'" Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net References: <1406328445-63707-1-git-send-email-jaegeuk@kernel.org> <1406328445-63707-8-git-send-email-jaegeuk@kernel.org> <009901cfab97$f2981be0$d7c853a0$@samsung.com> <20140730031820.GC99885@jaegeuk-mac02> In-reply-to: <20140730031820.GC99885@jaegeuk-mac02> Subject: RE: [f2fs-dev] [PATCH 08/11] f2fs: fix wrong condition for unlikely Date: Wed, 30 Jul 2014 20:58:37 +0800 Message-id: <00f401cfabf6$14f52b70$3edf8250$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Content-language: zh-cn Thread-index: AQH0/sFA7oYZ7Fd/hcfctysO+ZeFcgGwpqWeAfWylWMB2iR7tptB5/Rg X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrKLMWRmVeSWpSXmKPExsVy+t9jQV2NNzeCDRp2Clk8WT+L2eLSIneL PXtPslhc3jWHzYHFY9OqTjaP3Qs+M3l83iQXwBzFZZOSmpNZllqkb5fAlXH1xEH2ghaJigcz 5jM2MK4T7mLk5JAQMJF407iABcIWk7hwbz1bFyMXh5DAdEaJ7hULmCGcH4wSS3o2MoNUsQmo SCzv+M8EYosIqEn07psCZjMLZEpM6H/BDtFwhVFi947rQKM4ODgFjCU2/QWrERbwkVjbPZkF JMwioCrxbKYeSJhXwFLi5oYPTBC2oMSPyfdYIEZqSazfeRxqvLzE5jVvmSEOVZDYcfY1I0Rc XGLjkVssEOe4Seyd8J59AqPQLCSjZiEZNQvJqFlI2hcwsqxiFE0tSC4oTkrPNdIrTswtLs1L 10vOz93ECA78Z9I7GFc1WBxiFOBgVOLhnfH/erAQa2JZcWXuIUYJDmYlEd7GpzeChXhTEiur Uovy44tKc1KLDzFKc7AoifMebLUOFBJITyxJzU5NLUgtgskycXBKNTA2fn0Ue6zxTf0+E0/z 7aenHv5+WPtx3H2rXdo6O7hPb53AWWM17cBJofCCnMSu/qdhW1UYV0zSXRLItfnXncc7Xh8R 9TeeFHp3q9fGFqvY80I/JSqnhIW0JM+RUDYUPfFiAsPbsn3vqvxTN891WOBhHnSR6dEEwV7e w3ZdJU+Ot1b6atwq3a2oxFKckWioxVxUnAgAk3jbnHgCAAA= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org] > Sent: Wednesday, July 30, 2014 11:18 AM > To: Chao Yu > Cc: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org; > linux-f2fs-devel@lists.sourceforge.net > Subject: Re: [f2fs-dev] [PATCH 08/11] f2fs: fix wrong condition for unlikely > > On Wed, Jul 30, 2014 at 09:44:43AM +0800, Chao Yu wrote: > > Hi Jaegeuk, > > > > > -----Original Message----- > > > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org] > > > Sent: Saturday, July 26, 2014 6:47 AM > > > To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org; > > > linux-f2fs-devel@lists.sourceforge.net > > > Cc: Jaegeuk Kim > > > Subject: [f2fs-dev] [PATCH 08/11] f2fs: fix wrong condition for unlikely > > > > > > This patch fixes the wrongly used unlikely condition. > > > > > > Signed-off-by: Jaegeuk Kim Reviewed-by: Chao Yu > > > --- > > > fs/f2fs/checkpoint.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c > > > index 42a16c1..36b0d47 100644 > > > --- a/fs/f2fs/checkpoint.c > > > +++ b/fs/f2fs/checkpoint.c > > > @@ -932,7 +932,7 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount) > > > /* Here, we only have one bio having CP pack */ > > > sync_meta_pages(sbi, META_FLUSH, LONG_MAX); > > > > > > - if (unlikely(!is_set_ckpt_flags(ckpt, CP_ERROR_FLAG))) { > > > + if (!is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) { > > > > Maybe use likely(!is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) or > > > > if (unlikely(is_set_ckpt_flags(ckpt, CP_ERROR_FLAG))) > > return; > > > > is more appropriate. How do you think? > > Currently I'd like to put this without any likely or unlikely. > Best thing is to measure some performance how this would make effect on. I think we could get little improvement of performance if we use likely or unlikely here. So if you'd like leave it without pre-judgment, it will be ok. Let's just leave it as it was. :) Thanks, > Until then, it'd be better to do without it, since apparently this should > not be unlikely. > > How about you? > Can we compare both of them explicitly? > > Thanks, > > > > > > clear_prefree_segments(sbi); > > > release_dirty_inode(sbi); > > > F2FS_RESET_SB_DIRT(sbi); > > > -- > > > 1.8.5.2 (Apple Git-48) > > > > > > > > > ------------------------------------------------------------------------------ > > > Want fast and easy access to all the code in your enterprise? Index and > > > search up to 200,000 lines of code with a free copy of Black Duck > > > Code Sight - the same software that powers the world's largest code > > > search on Ohloh, the Black Duck Open Hub! Try it now. > > > http://p.sf.net/sfu/bds > > > _______________________________________________ > > > Linux-f2fs-devel mailing list > > > Linux-f2fs-devel@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/