Re: [PATCH] only irq-safe atomic ops

From: yodaiken@fsmlabs.com
Date: Sat Feb 23 2002 - 17:48:06 EST


On Sat, Feb 23, 2002 at 02:40:58PM -0800, Andrew Morton wrote:
> yodaiken@fsmlabs.com wrote:
> >
> > Is this part of some scheme to make the GPL support model actually
> > pay?
>
> No, no, no. It's all the uncommented code which brings in the dollars.
>
> > c = smp_get_cpuid(); // disables preemption
> >
> > ...
> > f(); // oops, me forgotee, this function also references cpuid
> > ..
> > x = ++local_cache[c]; // live dangerously
> > smp_put_cpuid(); // G_d knows what that does now.
> >
>
> preempt_disable() nests. It's not a problem.

Ah, got the reference count already! Good progress.
Is it irq safe yet?

BTW: Robert, whats a good kernel version that you recommend with
preemption patch? I want to rerun some tests.

-- 
---------------------------------------------------------
Victor Yodaiken 
Finite State Machine Labs: The RTLinux Company.
 www.fsmlabs.com  www.rtlinux.com

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sat Feb 23 2002 - 21:00:53 EST