linux-kernel - Re: [RESEND][PATCH v2] block: remove plugging at buffered write time

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:	Mon, 09 Apr 2012 10:34:44 -0400
From:	Jeff Moyer <jmoyer@...hat.com>
To:	Wu Fengguang <fengguang.wu@...el.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Jens Axboe <axboe@...nel.dk>, linux-fsdevel@...r.kernel.org,
	LKML <linux-kernel@...r.kernel.org>,
	Dave Chinner <david@...morbit.com>,
	Christoph Hellwig <hch@...radead.org>, Jan Kara <jack@...e.cz>,
	Chris Mason <chris.mason@...cle.com>,
	Shaohua Li <shli@...ionio.com>
Subject: Re: [RESEND][PATCH v2] block: remove plugging at buffered write time

Wu Fengguang <fengguang.wu@...el.com> writes:

> Buffered write(2) is not directly tied to IO, so it's not suitable to
> handle plug in generic_file_aio_write().
[snip, moved]
> Note that plugging for O_SYNC writes is also removed. The user may pass
> arbitrary @size arguments, which may be much larger than the preferable
> I/O size, or may cross extent/device boundaries. Let the lower layers
> handle the plugging. Otherwise the plugging code here will turn the
> low level plugging into no-ops.

I assume you have some numbers to back this up, right?  Care to share
those?

> Also moves unplugging for direct I/O from around ->direct_IO() down to
> do_blockdev_direct_IO().

This could be handled in a separate patch.  Acked-by: Jeff Moyer
<jmoyer@...hat.com> for this part.

Cheers,
Jeff
--
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/