From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chao Yu Subject: RE: [f2fs-dev] [PATCH] f2fs: check all ones or zeros bitmap with integer data type for better mount performance Date: Wed, 23 Oct 2013 11:23:52 +0800 Message-ID: <000001cecf9f$7113b630$533b2290$@samsung.com> References: <000701cecf09$2b2a2280$817e6780$@samsung.com> <1382444612.992.67.camel@kjgkr> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, =?utf-8?B?J+iwreWnnSc=?= To: jaegeuk.kim@samsung.com Return-path: Received: from mailout3.samsung.com ([203.254.224.33]:12916 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755459Ab3JWDZJ convert rfc822-to-8bit (ORCPT ); Tue, 22 Oct 2013 23:25:09 -0400 In-reply-to: <1382444612.992.67.camel@kjgkr> Content-language: zh-cn Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Hi, Kim: > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk.kim@samsung.com] > Sent: Tuesday, October 22, 2013 8:24 PM > To: Chao Yu > Cc: linux-f2fs-devel@lists.sourceforge.net; linux-fsdevel@vger.kernel= =2Eorg; > linux-kernel@vger.kernel.org; =E8=B0=AD=E5=A7=9D > Subject: Re: [f2fs-dev] [PATCH] f2fs: check all ones or zeros bitmap = with integer > data type for better mount performance >=20 > Hi, >=20 > 2013-10-22 (=ED=99=94), 17:28 +0800, Chao Yu: > > Previously, check_block_count check valid_map with bit data type in > > common scenario that sit has all ones or zeros bitmap, it makes low > > mount performance. > > So let's check the special bitmap with integer data type instead of > > the bit one. > > > > Signed-off-by: Tan Shu > > Signed-off-by: Yu Chao > > --- > > fs/f2fs/segment.h | 13 +++++++++++++ > > 1 file changed, 13 insertions(+) > > > > diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index > > 7f94d78..d43ab9f 100644 > > --- a/fs/f2fs/segment.h > > +++ b/fs/f2fs/segment.h > > @@ -543,6 +543,7 @@ static inline void check_block_count(struct > > f2fs_sb_info *sbi, { > > struct f2fs_sm_info *sm_info =3D SM_I(sbi); > > unsigned int end_segno =3D sm_info->segment_count - 1; > > + int *valid_map =3D (int *)raw_sit->valid_map; > > int valid_blocks =3D 0; > > int i; > > > > @@ -552,6 +553,19 @@ static inline void check_block_count(struct > > f2fs_sb_info *sbi, > > /* check boundary of a given segment number */ > > BUG_ON(segno > end_segno); > > > > + /* check all ones or zeros valid_map */ > > + if (GET_SIT_VBLOCKS(raw_sit) =3D=3D 0) { > > + for (i =3D 0; i < SIT_VBLOCK_MAP_SIZE / sizeof(int); i++) >=20 > We cannot guarantee all the time that SIT_VBLOCK_MAP_SIZE is multiple= of > sizeof(int). Well, It's really large changes for f2fs if SIT_VBLOCK_MAP_SIZE value i= s being modified. > How about using memcmp() with __u8? Do you mean that we can alloc all zeros or ones memory in SIT_VBLOCK_MA= P_SIZE size, then memcmp() it with sit bitmap by __u8? >=20 > > + if (unlikely(valid_map[i] !=3D 0)) > > + BUG(); > > + return; > > + } else if (GET_SIT_VBLOCKS(raw_sit) =3D=3D sbi->blocks_per_seg) { > > + for (i =3D 0; i < SIT_VBLOCK_MAP_SIZE / sizeof(int); i++) > > + if (unlikely(valid_map[i] !=3D -1)) > > + BUG(); > > + return; > > + } > > + > > /* check bitmap with valid block count */ > > for (i =3D 0; i < sbi->blocks_per_seg; i++) > > if (f2fs_test_bit(i, raw_sit->valid_map)) > > --- > > > > -- > > To unsubscribe from this list: send the line "unsubscribe > > linux-fsdevel" in the body of a message to majordomo@vger.kernel.or= g > > More majordomo info at http://vger.kernel.org/majordomo-info.html >=20 > -- > Jaegeuk Kim > Samsung -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html