Re: PowerPC fastpaths for mutex subsystem

Joel Schopp <jschopp@xxxxxxxxxxxxxx> wrote:
>
> This is the second pass at optimizing the fastpath for the new mutex subsystem
> on PowerPC. I think it is ready to be included in the series with the other
> mutex patches now. Tested on a 4 core (2 SMT threads/core) Power5 machine with
> gcc 3.3.2.
>
> Test results from synchro-test.ko:
>
> All tests run for default 5 seconds
> Threads semaphores mutexes mutexes+attached
> 1 63,465,364 58,404,630 62,109,571
> 4 58,424,282 35,541,297 37,820,794
> 8 40,731,668 35,541,297 40,281,768
> 16 38,372,769 37,256,298 41,751,764
> 32 38,406,895 36,933,675 38,731,571
> 64 37,232,017 36,222,480 40,766,379
>

Doens't this mean that the sped-up mutexes are still slower than semaphores?
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