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Re: djprobes status


Ingo Molnar wrote:
> On Fri, 2006-09-15 at 15:52 -0400, Satoshi Oshima wrote:
>> Actually, the implementation will be much more complex because
>> we have to think about multiple probes and multiple processors.
>> But basically I can see the solution in your advice. 
> 
> there's a fifth option too i can think of: just dont free probe buffers
> but put them into a linked list! Once there's too many of them, do the
> gather/release thing once, to release a bunch of buffers at once. That
> way the overhead of the gather/release will trigger only seldomly.
> 
> this is faster than the pushl based one, and much simpler as well i
> believe.

Link list approach still requires to use preempt_disable()/enable() or
freeze_process() because we can not guarantee the safety that all the 
buffer is not preempted. I think it is not enough to put buffers away
to linked list for a long time.

And yes, we will use linked list batch approach for recycle buffers.

Satoshi




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