mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@elte.hu>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Thomas Gleixner <tglx@linutronix.de> Gleixner"
	<tglx@linutronix.de>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Enable polling for disabled screaming irqs
Date: Fri, 18 Jul 2008 19:22:31 +0200	[thread overview]
Message-ID: <20080718172231.GM6875@elte.hu> (raw)
In-Reply-To: <m13amho1fd.fsf@frodo.ebiederm.org>


* Eric W. Biederman <ebiederm@xmission.com> wrote:

> When we disable a screaming irq we never see it again.  If the irq 
> line is shared or if the driver half works this is a real pain.  So 
> periodically poll the handlers for screaming interrupts.
> 
> I use a timer instead of the classic irq poll technique of working off 
> the timer interrupt because when we use the local apic timers 
> note_interrupt is never called (bug?).  Further on a system with 
> dynamic ticks the timer interrupt might not even fire unless there is 
> a timer telling it it needs to.
> 
> I forced this case on my test system with an e1000 nic and my ssh 
> session remained responsive despite the interrupt handler only being 
> called every 10th of a second.

very nice idea!

I have applied your patch to tip/genirq, thanks Eric. We need more 
kernel robustness features like this.

	Ingo

      reply	other threads:[~2008-07-18 17:22 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-07-10 21:48 Eric W. Biederman
2008-07-18 17:22 ` Ingo Molnar [this message]

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=20080718172231.GM6875@elte.hu \
    --to=mingo@elte.hu \
    --cc=ebiederm@xmission.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tglx@linutronix.de \
    /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

Powered by JetHome