Re: [take13 0/3] kevent: Generic event handling mechanism.

On Wed, Aug 23, 2006 at 10:56:24PM +0400, Evgeniy Polyakov (johnpol@xxxxxxxxxxx) wrote:
It can be done by selecting special event type, which in turn will reuse
special fields as length.
But variable-sized members can not be put into cache and without
knowledge of it's size it is impossible to put htem into mapped buffer.

And thinking more about this issue, I can say that I'm again
variable-sized structures - they can not be placed into ring buffer (at
least into simple one), they do not allow allocation from cache, it is
impossible to get them correctly from userspace if there is now exact
knowledge about nature of that events and a lot of other problems.
If one strongly feels that it is required, it is possible to provide
userspace pointer in the ukevent structure, which then can be read in
->enqueue callback by kernelside (there is similar trick in network
AIO).

I've reread my text - sorry for tons of errors, I use extremely slow
GPRS link, so it is almost impossible to return and correct errors using
it, I think it is simple to understand what I meant :)

--
Evgeniy Polyakov
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