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On Mon, 2005-06-13 at 09:44 +0200, Esben Nielsen wrote: > On Mon, 13 Jun 2005, Sven-Thorsten Dietrich wrote: > > > On Sat, 2005-06-11 at 22:03 +0200, Ingo Molnar wrote: > > > * Esben Nielsen <simlo@phys.au.dk> wrote: > > > > > > > > the jury is still out on the accuracy of those numbers. The test had > > > > > RT_DEADLOCK_DETECT (and other -RT debugging features) turned on, which > > > > > mostly work with interrupts disabled. The other question is how were > > > > > interrupt response times measured. > > > > > > > > > You would accept a patch where I made this stuff optional? > > > > > > I'm not sure why. The soft-flag based local_irq_disable() should in fact > > > be a tiny bit faster than the cli based approach, on a fair number of > > > CPUs. But it should definitely not be slower in any measurable way. > > > > > > > Is there any such SMP concept as a local_preempt_disable() ? > > > You must think of preempt_disable() ? Except for the interface is a little > bit different using flags in local_irq_save(), preempt_disable() works > exactly the same way, blocking for everything but interrupts - on the > _local_ CPU. (Under PREEMPT_RT it ofcourse also blocks for threaded IRQ > handlers.) Doesn't preempt_disable() also block rescheduling on other CPUs? We only need to prevent rescheduling on THIS CPU. - 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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