On 09/27/2011 05:36 PM, Jan Kiszka wrote:
On 2011-09-27 16:34, Avi Kivity wrote:
> On 09/27/2011 05:29 PM, Jan Kiszka wrote:
>>>
>>> Moreover, the eventfd() counter is not lossy (practically speaking)
whereas if
>>> you use pipe() as a counter, it will be lossy in practice.
>>>
>>> This is why posix aio uses pipe() and not eventfd().
>>
>> I don't get this yet. eventfd is lossy by default. It only decreases the
>> counter on read if you specify EFD_SEMAPHORE - which we do not do.
>>
>
> It's not lossy - a read returns the number of events written since the
> last read.
Yeah, but what's the point? We don't evaluate this.
If we write an interface that looks like eventfd but subtly differs,
someone will get bitten. If we write a new interface and implement it
via eventfd (or a pipe), no one gets bitten.
--
error compiling committee.c: too many arguments to function
