linux-kernel - Re: [PATCH] target/file: don't zero iter before iov_iter

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <BYAPR04MB49653C92C7925B8C3EAEF3CE86AD0@BYAPR04MB4965.namprd04.prod.outlook.com>
Date:   Sat, 9 Jan 2021 20:52:15 +0000
From:   Chaitanya Kulkarni <Chaitanya.Kulkarni@....com>
To:     Pavel Begunkov <asml.silence@...il.com>,
        "Martin K . Petersen" <martin.petersen@...cle.com>
CC:     "linux-scsi@...r.kernel.org" <linux-scsi@...r.kernel.org>,
        "target-devel@...r.kernel.org" <target-devel@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] target/file: don't zero iter before iov_iter_bvec

On 1/9/21 12:40, Pavel Begunkov wrote:
> I expect you won't find any, but such little things can pile up
> into a not-easy-to-spot overhead over time.

That is what I suspected with the resulting assembly. The commit log
needs to document that there is no direct impact on the performance
which can be seen with this patch, but this is nice to have
micro-optimization in the long run.