Re: [PATCH] only irq-safe atomic ops

Andrew Morton
2002-02-23T22:42:53Z

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.

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