Re: LTTng "TIF_KERNEL_TRACE"

[Frederic Weisbecker]

On Tue, Apr 28, 2009 at 12:38:25PM -0400, Mathieu Desnoyers wrote:
> No, read-write lock is a "special case" where it does not deadlock if
> you have an interrupt handler taking the read lock over another read
> lock. It's just the write lock that _must absolutely_ disable
> interrupts.


Ah, you're right, I was thinking with spinlock rules in mind :)


> However, the "latency race" scenario I explained above applies here,
> because the write lock disables interrupts and the read locks doesn't.
> 
> Mathieu
> 

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