From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH 0/2] eventfd: new EFD_STATE flag
Date: Thu, 27 Aug 2009 11:06:47 +0300
Message-ID: <20090827080647.GA7460@redhat.com>
References: <20090825072229.GA10608@redhat.com> <alpine.DEB.2.00.0908251456230.18518@makko.or.mcafeemobile.com> <20090826102908.GA21523@redhat.com> <alpine.DEB.2.00.0908261040100.7780@makko.or.mcafeemobile.com> <4A9585EC.2030505@redhat.com> <alpine.DEB.2.00.0908261201570.7780@makko.or.mcafeemobile.com> <4A95900D.9090201@redhat.com> <alpine.DEB.2.00.0908261242530.7780@makko.or.mcafeemobile.com> <alpine.DEB.2.00.0908261626410.7780@makko.or.mcafeemobile.com> <4A9607EC.2080304@redhat.com>
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Cc: Davide Libenzi <davidel@xmailserver.org>, gleb@redhat.com,
	kvm@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On Thu, Aug 27, 2009 at 07:13:32AM +0300, Avi Kivity wrote:
> On 08/27/2009 02:30 AM, Davide Libenzi wrote:
>> On Wed, 26 Aug 2009, Davide Libenzi wrote:
>>
>>    
>>>> I see no kernel equivalent to read(), but that's easily done.
>>>>        
>>> Adding an in-kernel read based on "ctx", that is no problem at all.
>>>      
>> Something like the untested below.
>> I had thought you said the eventfd readers where in userspace, but I might
>> have misunderstood you.
>>    
>
> No, they're all over the place.

Further, with Davide's proposal you must be a reader to signal events.

> -- 
> I have a truly marvellous patch that fixes the bug which this
> signature is too narrow to contain.