From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757986Ab2EOIEH (ORCPT ); Tue, 15 May 2012 04:04:07 -0400 Received: from cantor2.suse.de ([195.135.220.15]:52979 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757898Ab2EOIEA (ORCPT ); Tue, 15 May 2012 04:04:00 -0400 Date: Tue, 15 May 2012 18:03:49 +1000 From: NeilBrown To: Yuanhan Liu Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] md: remove redudent code Message-ID: <20120515180349.0f0d275e@notabene.brown> In-Reply-To: <1337068825-11995-1-git-send-email-yuanhan.liu@linux.intel.com> References: <1337068825-11995-1-git-send-email-yuanhan.liu@linux.intel.com> X-Mailer: Claws Mail 3.7.10 (GTK+ 2.24.7; x86_64-suse-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/VqFEOse+MAiSHk0f6D8+1c4"; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/VqFEOse+MAiSHk0f6D8+1c4 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Tue, 15 May 2012 16:00:25 +0800 Yuanhan Liu wrote: > The code does nothing but repating assigning sb->sb_csum with original > value. This code sets the sb_csum to 0 while the csum is calculated. Without this, calculating the csum, setting it, then calculating again would produce a different result. So the code is correct as is. Thanks, NeilBrown >=20 > Signed-off-by: Yuanhan Liu > --- > drivers/md/md.c | 4 ---- > 1 files changed, 0 insertions(+), 4 deletions(-) >=20 > diff --git a/drivers/md/md.c b/drivers/md/md.c > index 0bd44e3..f2d799a 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -1439,15 +1439,12 @@ super_90_rdev_size_change(struct md_rdev *rdev, s= ector_t num_sectors) > =20 > static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb) > { > - __le32 disk_csum; > u32 csum; > unsigned long long newcsum; > int size =3D 256 + le32_to_cpu(sb->max_dev)*2; > __le32 *isuper =3D (__le32*)sb; > int i; > =20 > - disk_csum =3D sb->sb_csum; > - sb->sb_csum =3D 0; > newcsum =3D 0; > for (i=3D0; size>=3D4; size -=3D 4 ) > newcsum +=3D le32_to_cpu(*isuper++); > @@ -1456,7 +1453,6 @@ static __le32 calc_sb_1_csum(struct mdp_superblock_= 1 * sb) > newcsum +=3D le16_to_cpu(*(__le16*) isuper); > =20 > csum =3D (newcsum & 0xffffffff) + (newcsum >> 32); > - sb->sb_csum =3D disk_csum; > return cpu_to_le32(csum); > } > =20 --Sig_/VqFEOse+MAiSHk0f6D8+1c4 Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.18 (GNU/Linux) iQIVAwUBT7IN5Tnsnt1WYoG5AQKRPQ//YQsOhXUHzslLwVvne50qinZ/cOlvnf3U 4M8KK76JCF09dgKOSxPKZQuCMJsFETThy2l6vGcv+gEqHjoGMtqqZoFJCmKxpZuq wJDVjez9mLGlQMPkymkzkrZrJ9lFKFFdqlGyR4osaURBMquDeE1OWbfkN8oZOOWS GURGKY8IEQ9nTYHZ1GA8i5Ub6J7vs66HpireKmgL/T7ONHSbtG9MsinPUvXxEzEc SXEczi8NHHTi4FfreuoQsm7fA8YB54E8dwFlAGLGWoNEzXbqd1KEVgaQqdbf4KcM U8d5gP3qcBKFBee+UGgwHORJtwBWxCsbLafdWtmSqvkfZ/u0H5m9KlEyzF8M5MQL UGruardVlC38Ap8tWks9Wi0umDkFTv+qgUaZZyeCzylwIIQ7ffurA5Om1v1PT7z5 Rmj6hScVGvhQnkYuaLRnbLtc9v/Uxd4KRjq2SaPEtr8g2+h+haRIb/yqzIg8YaUR ubjiVeu08k/xffMq9FVfkbmKEh1Tm7EasHXXn5kXTntnvLrUXiinth2HVRZU4tch RTczV9dlc6Su7S3W+gkcSZpQ82dB+6YKJ0emig8ww31dG0YCDQrONy9+k0hgzI8Q 4tberdSaWNEi5VxwiHBGwq83ogL6XNyQjLR1nVsYMaFC+gQ4eFtsxpC3dJAFotdd N2xUpmSPqqs= =0R+N -----END PGP SIGNATURE----- --Sig_/VqFEOse+MAiSHk0f6D8+1c4--