linux-kernel - Re: [PATCH 0/8] sdhci: Move real work out of an atomic context

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: <20100721141352.d7993493.akpm@linux-foundation.org>
Date:	Wed, 21 Jul 2010 14:13:52 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Anton Vorontsov <avorontsov@...sta.com>
Cc:	Wolfram Sang <w.sang@...gutronix.de>,
	Albert Herranz <albert_herranz@...oo.es>,
	Matt Fleming <matt@...sole-pimps.org>,
	Ben Dooks <ben-linux@...ff.org>,
	Pierre Ossman <pierre@...man.eu>, linux-mmc@...r.kernel.org,
	linux-kernel@...r.kernel.org, linuxppc-dev@...abs.org
Subject: Re: [PATCH 0/8] sdhci: Move real work out of an atomic context

On Wed, 14 Jul 2010 17:07:28 +0400
Anton Vorontsov <avorontsov@...sta.com> wrote:

> Hi all,
> 
> Currently the sdhci driver does everything in the atomic context.
> And what is worse, PIO transfers are made from the IRQ handler.
> 
> This causes huge latencies (up to 120 ms). On some P2020 SOCs,
> DMA and card detection is broken, which means that kernel polls
> for the card via PIO transfers every second. Needless to say
> that this is quite bad.
> 
> So, this patch set reworks sdhci code to avoid atomic context,
> almost completely. We only do two device memory operations
> in the atomic context, and all the rest is threaded.
> 
> I noticed no throughput drop neither with PIO transfers nor
> with DMA (tested on MPC8569E CPU), while latencies should be
> greatly improved.
> 

The patchset looks good to me, but it'd be nice to hear from the other
people who work on this code, please?

--
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/