Con Kolivas wrote:
> On Friday 02 June 2006 17:53, Nick Piggin wrote:
> 
>>This is a small micro-optimisation / cleanup we can do after
>>smtnice gets converted to use trylocks. Might result in a little
>>less cacheline footprint in some cases.
> 
> 
> It's only dependent_sleeper that is being converted in these patches. The 
> wake_sleeping_dependent component still locks all runqueues and needs to 

Oh I missed that.

> succeed in order to ensure a task doesn't keep sleeping indefinitely. That 

Let's make it use trylocks as well. wake_priority_sleeper should ensure
things don't sleep forever I think? We should be optimising for the most
common case, and in many workloads, the runqueue does go idle frequently.

> one doesn't get called from schedule() so is far less expensive. This means I 
> don't think we can change that cpu based locking order which I believe was 
> introduce to prevent a deadlock (?DaveJ disovered it iirc).
> 

AntonB, I think.

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