public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jiri Bohac <jbohac@suse.cz>
To: linux-kernel@vger.kernel.org
Cc: mingo@elte.hu, Yinghai Lu <yinghai@kernel.org>,
	akpm@linux-foundation.org, jbohac@suse.cz
Subject: Re: [PATCH] x86 apic: Ack all pending irqs when crashed/on kexec
Date: Wed, 17 Feb 2010 17:05:20 +0100	[thread overview]
Message-ID: <20100217160520.GA28084@midget.suse.cz> (raw)
In-Reply-To: <1266357790-8962-1-git-send-email-trenn@suse.de>

On Tue, Feb 16, 2010 at 11:03:10PM +0100, Thomas Renninger wrote:
> with MAX_LOOPS something like 1E9 this would leave plenty of time for the
> pending IRQs to be cleared and would and still cause at most a second of delay
> if the loop were to lock-up for whatever reason.
...
> +	int i, j, acked = 0, max_loops = 0x1E9;

I meant 1E9 == 1000000, not 0x1E9, just to give the kernel a
chance to boot (with a delay) if something is completely wrong.
0x1E9 might be too small.

I also think a warning should be printed in case max_loops decreases to
zero:

> +	    max_loops--;
> +        } while (queued && max_loops > 0);

+	WARN_ON(!max_loops)

Thanks,

-- 
Jiri Bohac <jbohac@suse.cz>
SUSE Labs, SUSE CZ


       reply	other threads:[~2010-02-17 16:05 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1266357790-8962-1-git-send-email-trenn@suse.de>
2010-02-17 16:05 ` Jiri Bohac [this message]
2010-02-23 11:51 [PATCH] x86 apic: Ack all pending irqs when crashed/on kexec Thomas Renninger
2010-02-23 12:01 ` Thomas Renninger
2010-02-23 12:03 ` Avi Kivity
2010-02-26 19:47   ` Kerstin Jonsson
2010-03-08 10:18     ` Avi Kivity
  -- strict thread matches above, loose matches on Subject: below --
2010-03-08 11:17 Thomas Renninger
2010-03-08 11:26 ` Avi Kivity
2010-03-08 11:26 ` Thomas Renninger
2010-03-08 11:34 ` Cyrill Gorcunov
2010-03-08 11:40   ` Thomas Renninger

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=20100217160520.GA28084@midget.suse.cz \
    --to=jbohac@suse.cz \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=yinghai@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