From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@qumranet.com>
Subject: Re: [PATCH 4/7] SMP: Implement on_one_cpu()
Date: Thu, 24 May 2007 16:48:04 +0300
Message-ID: <46559794.50208@qumranet.com>
References: <1180008615579-git-send-email-avi@qumranet.com>	<11800086152009-git-send-email-avi@qumranet.com> <adaejl68hh7.fsf@cisco.com>
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Cc: kvm-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org,
	shaohua.li@intel.com, lhcs-devel@lists.sourceforge.net
To: Roland Dreier <rdreier@cisco.com>
Return-path: <linux-kernel-owner+glk-linux-kernel-3=40m.gmane.org-S1751011AbXEXNsT@vger.kernel.org>
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Roland Dreier wrote:
> I don't see any documented restrictions about preemption being
> disabled when this function is called, but...
>
>  > +int on_one_cpu(int cpu, void (*func) (void *info), void *info,
>  > +	       int retry, int wait)
>  > +{
>  > +	int ret;
>  > +	int this_cpu;
>  > +
>  > +	this_cpu = get_cpu();
>
> what if a preempt and reschedule to a different CPU happens right
> here, after this_cpu is set?
>
>  > +	if (this_cpu == cpu) {
>   

get_cpu() disables preemption (the return value would be meaningless 
otherwise).


-- 
error compiling committee.c: too many arguments to function