linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tang Chen <tangchen@cn.fujitsu.com>
To: Borislav Petkov <bp@alien8.de>, Borislav Petkov <bp@amd64.org>,
	tony.luck@intel.com, tglx@linutronix.de, mingo@redhat.com,
	hpa@zytor.com, miaox@cn.fujitsu.com, laijs@cn.fujitsu.com,
	wency@cn.fujitsu.com, x86@kernel.org, linux-edac@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] Replace if statement with WARN_ON_ONCE() in cmci_rediscover().
Date: Tue, 23 Oct 2012 10:55:13 +0800	[thread overview]
Message-ID: <50860711.10807@cn.fujitsu.com> (raw)
In-Reply-To: <20121022101442.GB8352@liondog.tnic>

On 10/22/2012 06:14 PM, Borislav Petkov wrote:
> On Mon, Oct 22, 2012 at 10:10:24AM +0800, Tang Chen wrote:
>> I don't why before we just jumped over it. But I think if we have an
>> online cpu == dying here, it must be wrong. So I think we should warn
>> it, not just jump over it.
>
> Why do we need to warn? What good would that bring us?
>
> AFAICT, the check in cmci_rediscover is there to make sure we absolutely
> don't rediscover on the dying cpu. I think it is a safety precaution in
> concurrency scenarios between cpu hotplug and mce code.

Well, I see. I dropped the if statement. :)

So, how about warn once, and continue:
	if (cpu == dying) {
		WARN_ON_ONCE(cpu == dying);
		continue;
	}

or, use BUG_ON() instead ?

>
> Thanks.
>


  parent reply	other threads:[~2012-10-23  2:56 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-19  5:45 [PATCH v2 0/2] Do not change worker's running cpu in cmci_rediscover() Tang Chen
2012-10-19  5:45 ` [PATCH v2 1/2] Replace if statement with WARN_ON_ONCE() " Tang Chen
2012-10-19 14:07   ` Greg KH
2012-10-19 16:40   ` Borislav Petkov
2012-10-22  2:10     ` Tang Chen
2012-10-22 10:14       ` Borislav Petkov
2012-10-23  1:35         ` Tang Chen
2012-10-23  2:55         ` Tang Chen [this message]
2012-10-23  9:52           ` Borislav Petkov
2012-10-23 10:17             ` Miao Xie
2012-10-23 10:20               ` Borislav Petkov
2012-10-23 10:34                 ` Miao Xie
2012-10-23 13:14                   ` Borislav Petkov
2012-10-23 11:30             ` Tang Chen
2012-10-23 14:17               ` Borislav Petkov
2012-10-23 16:16               ` Luck, Tony
2012-10-24  1:31                 ` Tang Chen
2012-10-19  5:45 ` [PATCH v2 2/2] Do not change worker's running cpu " Tang Chen
2012-10-19 16:42   ` Borislav Petkov
2012-10-19 17:21     ` Luck, Tony
2012-10-22  3:33       ` Tang Chen
2012-10-22 10:18         ` Borislav Petkov
2012-10-23  1:30           ` Tang Chen
2012-10-19  7:21 ` [PATCH v2 0/2] " Tang Chen

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=50860711.10807@cn.fujitsu.com \
    --to=tangchen@cn.fujitsu.com \
    --cc=bp@alien8.de \
    --cc=bp@amd64.org \
    --cc=hpa@zytor.com \
    --cc=laijs@cn.fujitsu.com \
    --cc=linux-edac@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=miaox@cn.fujitsu.com \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=wency@cn.fujitsu.com \
    --cc=x86@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;
as well as URLs for NNTP newsgroup(s).