Messages in this thread | | | Subject | Re: [PATCH RFC V2 3/5] jump_label: if a key has already been initialized, don't nop it out | From | Steven Rostedt <> | Date | Thu, 06 Oct 2011 18:08:34 -0400 |
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On Thu, 2011-10-06 at 14:39 -0700, Jeremy Fitzhardinge wrote:
> I'm not sure it would be a win, necessarily. My test with back-to-back > jmp2 was definitely slower than with the nop padding it out to 5 bytes; > I suspect that's a result of having too many jmps within one cacheline. > Of course, there's no reason why the CPU would optimise for jumps to > jumps, so perhaps its just hitting a "stupid programmer" path.
Just a note. Micro-benchmarks are known to be as good as political polls and statistics. They show a much different view of the world than what is really there.
-- Steve
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