Messages in this thread | | | Date | Thu, 21 Feb 2013 21:58:50 +0000 | From | Russell King - ARM Linux <> | Subject | Re: [RFC/PATCH 2/5] kernel_cpustat: convert to atomic 64-bit accessors |
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On Thu, Feb 21, 2013 at 10:53:07PM +0100, Frederic Weisbecker wrote: > That too should be kcpustat_this_cpu_set(), or kcpustat_this_cpu_add() > FWIW. But we probably don't need the overhead of atomic_add() that > does a LOCK. > atomic_set(var, atomic_read(var) + delta) would be better. All we need
You mean atomic64_set() and atomic64_read(). Looking at the generic version in lib/atomic64.c, atomic64_add() is cheaper for 32-bit arches because it doesn't involve taking the lock twice.
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