linux-kernel - Re: [PATCHv3 4/5] mtd: mxc

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: <AANLkTilG2AhYtQkb8V0u9851JP1vHhqrJTWKyRDGM36F@mail.gmail.com>
Date:	Fri, 25 Jun 2010 16:46:44 +0200
From:	Ivo Clarysse <ivo.clarysse@...il.com>
To:	Sascha Hauer <s.hauer@...gutronix.de>
Cc:	linux-arm-kernel@...ts.infradead.org,
	John Ogness <john.ogness@...utronix.de>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCHv3 4/5] mtd: mxc_nand fixups

On Thu, Jun 24, 2010 at 9:27 AM, Sascha Hauer <s.hauer@...gutronix.de> wrote:
[...]
>
> BTW I observed that at least on i.MX27 the latencies introduced by
> waiting for an interrupt cause a significant performance drop. The
> driver gets much faster when we just poll all the time. I don't know how
> this affects system performance otherwise, but it may be a possibility
> to drop interrupt support at least for i.MX21. I have no idea how long
> the longest possible time we'd have to poll is though.

I'm noticing the same thing on i.MX21: when using interrupts,
"Scanning device for bad blocks" takes 982 (!) seconds.  When always
using polling, the same scan takes 'only' 500 seconds.


Ivo.
--
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/