Greetings... a patch I would like your comments on...

Randall Stewart rrs at
Fri Jan 22 14:44:08 UTC 2010


Ok, over we go ;-)

I do want to add this into Head here eventually so if you happen
to have an interest in umtx or kqueue you may want to take a close
look at this patch ;-)

On Jan 22, 2010, at 5:27 AM, Ivan Voras wrote:

> 2010/1/22 Randall Stewart <rrs at>:
>> All:
>> I have put together a patch against head that I would like
>> your opinion of.
>> So first what does it do?
>> Well one thing I thought lacking in the kernel was the ability
>> to send a cond event (umtx_cond) to a thread that was waiting
>> on a kqueue...
>> So the rough idea is I have N fd's and other things I am watching
>> but I would also like a local thread (maybe remote if the  
>> umtx_cond_t is
>> in shared memory) to be able to wake me up as well.
> This is a good and useful addition! I think Windows has implemented a
> generalization of this (called "wait objects" or something like that),
> which effectively allows a select()- (or in this case kqueue())-like
> syscall to wait on both file descriptors and condvars (as well as
> probably other MS-style objects). It's useful for multiplexing events
> for dissimilar sources.
> But you will probably soon receive a message to take this discussion
> to hackers at, and I agree :)

Randall Stewart
803-317-4952 (cell)

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