Messages in this thread | | | Date | Mon, 16 Jul 2007 11:45:03 +0200 | From | Nick Piggin <> | Subject | Re: [rfc][patch 2/2] x86_64: FIFO ticket spinlocks |
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On Mon, Jul 16, 2007 at 11:26:46AM +0200, Ingo Molnar wrote: > > * Nick Piggin <npiggin@suse.de> wrote: > > > [...] trylock is more significantly slower, but they are relatively > > rare. > > trylock is the main thing that the spinlock debugging code uses, and > SPINLOCK_DEBUG is frequently enabled by distro kernels. OTOH, the cost > looks like to be +5 instructions, right? Still ...
Which trylocks do you mean? The lockbreak spinlocks use trylock, but those are not used with the ticket version.
I wouldn't be against adding an option between either of the lock types, if there was value in it. But I would like to default ticket locks to "y", at least in -rc kernels, in order to see if performance goes down anywhere. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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