Re: [PATCH] local_irq_disable removal

[Ingo Molnar]

* Sven-Thorsten Dietrich <sdietrich@xxxxxxxxxx> wrote:

> > > Is there any such SMP concept as a local_preempt_disable()  ?
> > > 
> > You must think of preempt_disable() ? Except for the interface is a little
> > bit different using flags in local_irq_save(), preempt_disable() works
> > exactly the same way, blocking for everything but interrupts - on the
> > _local_ CPU. (Under PREEMPT_RT it ofcourse also blocks for threaded IRQ
> > handlers.)
> 
> Doesn't preempt_disable() also block rescheduling on other CPUs?
> 
> We only need to prevent rescheduling on THIS CPU.

it doesnt. It's 2-4 instructions similar to the assembly i posted 
before, changing current_thread_info->preempt_count, nothing else.

	Ingo
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