From: Tejun Heo <tj@kernel.org>
To: Robert Hancock <hancockrwd@gmail.com>
Cc: Torsten Kaiser <just.for.lkml@googlemail.com>,
linux-kernel@vger.kernel.org, Jeff Garzik <jgarzik@pobox.com>,
linux-ide@vger.kernel.org
Subject: Re: MSI broken in libata?
Date: Mon, 11 Jan 2010 11:17:56 +0900 [thread overview]
Message-ID: <4B4A8A54.8030406@kernel.org> (raw)
In-Reply-To: <4B4A815A.60503@gmail.com>
Hello, Robert.
On 01/11/2010 10:39 AM, Robert Hancock wrote:
> It'd be interesting to see if it makes a difference, but I don't think
> the patch is quite right. According to the datasheet, doing the MSI ack
> while the interrupt source is still pending will cause a new MSI to be
> sent, so if you do it before handling the interrupt you'll generate a
> spurious interrupt after every real one.
Ah... okay, so the generation of MSI is level triggered? If so, your
original patch is correct. I was thinking it might be edge triggered
and it should be cleared before checking master event mask.
Thanks.
--
tejun
next prev parent reply other threads:[~2010-01-11 2:15 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-12-25 9:22 MSI broken in libata? Torsten Kaiser
2010-01-09 9:11 ` Tejun Heo
2010-01-10 4:33 ` Torsten Kaiser
2010-01-11 1:15 ` Tejun Heo
2010-01-11 1:39 ` Robert Hancock
2010-01-11 2:17 ` Tejun Heo [this message]
2010-01-16 21:58 ` Torsten Kaiser
2010-01-17 19:22 ` Robert Hancock
2010-01-17 21:11 ` Torsten Kaiser
2010-01-18 20:51 ` Torsten Kaiser
2010-01-19 2:03 ` Robert Hancock
2010-01-19 7:00 ` Torsten Kaiser
2010-01-19 20:20 ` Torsten Kaiser
2010-01-20 3:00 ` Robert Hancock
2010-01-20 6:48 ` Torsten Kaiser
2010-01-22 0:53 ` Robert Hancock
2010-01-11 6:44 ` Torsten Kaiser
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4B4A8A54.8030406@kernel.org \
--to=tj@kernel.org \
--cc=hancockrwd@gmail.com \
--cc=jgarzik@pobox.com \
--cc=just.for.lkml@googlemail.com \
--cc=linux-ide@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox