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

[Avi Kivity]

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.

The "last read value" needs to be maintained for each reader, which is 
not possible with read().

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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/