Re: [PATCH-RFC 2/2] eventfd: EFD_STATE flag

[Avi Kivity]

On 08/04/2009 12:23 PM, Gleb Natapov wrote:
> On Tue, Aug 04, 2009 at 12:25:49PM +0300, Avi Kivity wrote:
>    
> > On 08/04/2009 12:17 PM, Gleb Natapov wrote:
> >      
> > > > If a different read comes after the write but after our read, it will
> > > > have transferred the value, resulting in the same situation.
> > > >
> > > > I think reads should never block with a state based mechanism.
> > > >
> > > >
> > > >          
> > > Reader may want to poll for the status change.
> > >
> > >        
> > Without epoll(), it's inherently racy since reads from other processes
> > can clear the status.
> >
> >      
> This is correct for any file descriptor. Multiple readers shouldn't
> simultaneously read from the same files descriptor if they expect to
> make any sense from a result.
>    

I think counting eventfd is an exception, but in general you are right.

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

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