linux-kernel - Re: [PATCH] block: forbid to re-enable I/O stat accounting

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]

Date:	Sat, 21 Mar 2009 03:03:09 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Jerome Marchand <jmarchan@...hat.com>
Cc:	Jens Axboe <axboe@...nel.dk>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] block: forbid to re-enable I/O stat accounting


Please fix your email headers - what I received was

From: Jerome Marchand <jmarchan@...hat.com>
To: unlisted-recipients:;;@imap1.linux-foundation.org (no To-header on input)
Cc: Jens Axboe <axboe@...nel.dk>


On Thu, 19 Mar 2009 11:36:50 +0100 Jerome Marchand <jmarchan@...hat.com> wrote:

> When we stop I/O stat accounting we stop to update the in-flight
> requests counter and we need this counter to be reliable for
> accounting I/O stats. Unfortunately updating in_flight field may
> affect performance. So, until we have a better solution, just forbid
> to re-enable I/O stat accounting after it has been disabled.

hm.  Is it really so hard to just quiesce the device until all in-flight
requests have drained?  freeze_bdev() might be a suitable starting point?

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/