From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH v2 1/2] x86: defer processing events on the
	NMI exit path
Date: Fri, 1 Mar 2013 16:01:17 +0000
Message-ID: <5130D0CD.9090305@citrix.com>
References: <CD568020.5D214%keir@xen.org>
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To: Keir Fraser <keir@xen.org>
Cc: Malcolm Crossley <malcolm.crossley@citrix.com>, "Tim (Xen.org)" <tim@xen.org>, Jan Beulich <JBeulich@suse.com>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>
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On 01/03/13 15:56, Keir Fraser wrote:
> On 01/03/2013 11:53, "Jan Beulich" <JBeulich@suse.com> wrote:
>
>>> __softirq_pending is an unsigned long.  Would it not be prudent to use
>>> cmpq to save obscure bugs if the implementation changes, or are we
>>> sufficiently sure that this wont happen?
>> All other existing instances of similar assembly code use testl or
>> cmpl, and in fact I merely copied some other instance.
>>
>> As we're not getting close to 32, I think we might rather want to
>> adjust the __softirq_pending type. Keir?
> Yup, I don't see any reason why it couldn't be a uint32_t.
>
>  -- Keir
>
>

Further to that, is there any reason that it cant be per-cpu, to save
having information like this moving around pcpus in a hot cache line?

~Andrew