From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH-RFC 2/2] eventfd: EFD_STATE flag
Date: Tue, 4 Aug 2009 11:54:06 +0300
Message-ID: <20090804085406.GA3311@redhat.com>
References: <cover.1248803500.git.mst@redhat.com> <20090728175538.GC21549@redhat.com> <4A76FDB2.7080706@redhat.com> <20090803151426.GA3630@redhat.com> <4A770260.5000507@redhat.com> <20090803165708.GB3630@redhat.com> <4A77F6EF.8010002@redhat.com>
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To: Avi Kivity <avi@redhat.com>
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On Tue, Aug 04, 2009 at 11:53:03AM +0300, Avi Kivity wrote:
> On 08/03/2009 07:57 PM, Michael S. Tsirkin wrote:
>>> Why not do it at the point of the write?
>>>
>>>      if (value != ctx->count) {
>>>          ctx->count = value;
>>>          wake_things_up();
>>>      }
>>>      
>>
>> What if write comes before read?
>>    
>
> The read will get the new value.

Yes :) But how does read know it should not block?

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