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    SubjectRe: [PATCH] only irq-safe atomic ops
    Robert Love wrote:
    >
    > On Sat, 2002-02-23 at 18:13, Robert Love wrote:
    > > On Sat, 2002-02-23 at 17:10, Andrew Morton wrote:
    > >
    > > > ooh. me likee.
    > > >
    > > > #define smp_get_cpuid() ({ preempt_disable(); smp_processor_id(); })
    > > > #define smp_put_cpuid() preempt_enable()
    > > >
    > > > Does rml likee?
    > >
    > > Yah, that works.
    >
    > OK, I still likee, but I was just thinking, if we are going to add have
    > to add something why not consider the irq-safe atomic ops? It is
    > certainly the most optimal.
    >

    For the situation Victor described:

    const int cpu = smp_get_cpuid();

    per_cpu_array_foo[cpu] = per_cpu_array_bar[cpu] +
    per_cpu_array_zot[cpu];

    smp_put_cpuid();

    It's a nice interface - it says "pin down and return the current
    CPU ID".

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