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From: Robert Watson <rwatson@FreeBSD.org>
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Cc: svn-src-head@freebsd.org, Randall Stewart <rrs@freebsd.org>,
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	Julian Elischer <julian@freebsd.org>
Subject: Re: svn commit: r218232 - head/sys/netinet
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On Fri, 4 Feb 2011, Robert N. M. Watson wrote:

> On 4 Feb 2011, at 10:56, John Baldwin wrote:
>
>> The difference here is that FOREACH_THREAD_IN_PROC() is just a 
>> TAILQ_FOREACH().  The CPU iterators are more complex.
>>
>> I agree that that we should have topology-aware iterators, though part of 
>> the problem is what do you iterate?  We'd have to create new sets of 
>> package and core IDs.
>>
>> For HWTHREAD_FOREACH() you can already use CPU_FOREACH().
>
> Yeah, I have no real opinion on spelling at all. Rather, I'm of the opinion 
> that we need some more semantics in order to express useful concepts, and 
> make it easy to represent things like "one X per package", and "find me the 
> closest X to which I wish to enqueue this request".

And just to expand on this thought slightly: I'd like it to answer the 
question without dirtying cache lines for shared data (so no locks, etc). 
That way we can do it cheaply per-packet if need be.

Robert