Re: [PATCH 1/1] eventfd: implementation of EFD_MASK flag

From: Martin Sustrik
Date: Sat Feb 09 2013 - 02:36:18 EST

On 09/02/13 04:54, Eric Wong wrote:

Using one eventfd per userspace socket still seems a bit wasteful.

Wasteful in what sense? Occupying a slot in file descriptor table?
That's the price for having the socket uniquely identified by the

Yes. I realize eventfd is small, but I don't think eventfd is needed
at all, here. Just one pipe.

Ah. Got you! You mean not to change the kernel, just use pipe for the purpose.

However, the convoluted pipe-style design is the problem I am trying to solve rather than the solution. It leads to convoluted APIs with convoluted semantics as described in the article. I've been using that kind of design for past 8 years and every time I have to deal with it I swear that one day I will implement a proper in-kernel solution to get rid of the hack.

And now I have finally done so.

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