From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
To: yong.zhang0@gmail.com
Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
akpm@linux-foundation.org, kobayashi.kk@ncos.nec.co.jp,
heiko.carstens@de.ibm.com
Subject: Re: [PATCH 1/2] proc/insterrupts: make it cpu hotplug safe
Date: Wed, 27 Jul 2011 14:20:02 +0900 [thread overview]
Message-ID: <4E2FA002.2020302@jp.fujitsu.com> (raw)
In-Reply-To: <1311742583-18633-1-git-send-email-yong.zhang0@gmail.com>
(2011/07/27 13:56), Yong Zhang wrote:
> KOSAKI Motonhiro noticed that the reader of /proc/interrupts
> could be preempted by cpu hotplug, thus the reader can get
> broken result due to show_interrupts() iterate every online
> cpu without any protection.
>
> Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Keika Kobayashi <kobayashi.kk@ncos.nec.co.jp>
> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Looks good. but I have a question. On last thread, kobayashi-san
suggested to use for_each_possible_cpu() and you wrote "+1".
>> At that time, I suggested to change
>> from for_each_online_cpu() to for_each_possible_cpu(),
>> in /proc/interrupts.
>+1
>Thus we could also avoid the issue pointed by KOSAKI Motonhiro.
Why do you decide to use another way?
next prev parent reply other threads:[~2011-07-27 5:20 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-25 13:10 [PATCH] proc/softirqs: only show state for online cpus Yong Zhang
2011-07-26 5:28 ` KOSAKI Motohiro
2011-07-26 6:14 ` Yong Zhang
2011-07-26 6:38 ` KOSAKI Motohiro
2011-07-26 7:29 ` Yong Zhang
2011-07-26 7:46 ` Keika Kobayashi
2011-07-26 7:56 ` Yong Zhang
2011-07-26 7:52 ` KOSAKI Motohiro
2011-07-26 16:34 ` Heiko Carstens
2011-07-27 2:41 ` Yong Zhang
2011-07-27 4:56 ` [PATCH 1/2] proc/insterrupts: make it cpu hotplug safe Yong Zhang
2011-07-27 4:56 ` [PATCH 2/2] [S390] irq: fix show_interrupts() vs cpu hotplug Yong Zhang
2011-07-27 6:06 ` Heiko Carstens
2011-07-27 5:20 ` KOSAKI Motohiro [this message]
2011-07-27 5:47 ` [PATCH 1/2] proc/insterrupts: make it cpu hotplug safe Yong Zhang
2011-07-27 5:55 ` KOSAKI Motohiro
2011-07-27 6:05 ` Heiko Carstens
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