On Fri, Apr 06, 2007 at 11:25:00PM -0700, Andrew Morton wrote: > On Fri, 6 Apr 2007 14:41:50 -0700 "Keshavamurthy, Anil S" <[EMAIL PROTECTED]> > wrote: > > > Subject: Avoid checking for cpu gone when CONFIG_HOTPLUG_CPU not defined > > > > Avoid checking for cpu gone in mm hot path when > > CONFIG_HOTPLUG_CPU is not defined. > > > > Signed-off-by: Anil S Keshavamurthy <[EMAIL PROTECTED]> > > > > --- > > arch/i386/kernel/smp.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > Index: work/arch/i386/kernel/smp.c > > =================================================================== > > --- work.orig/arch/i386/kernel/smp.c > > +++ work/arch/i386/kernel/smp.c > > @@ -365,10 +365,12 @@ static void flush_tlb_others(cpumask_t c > > BUG_ON(cpu_isset(smp_processor_id(), cpumask)); > > BUG_ON(!mm); > > > > +#ifdef CONFIG_HOTPLUG_CPU > > /* If a CPU which we ran on has gone down, OK. */ > > cpus_and(cpumask, cpumask, cpu_online_map); > > - if (cpus_empty(cpumask)) > > + if (unlikely(cpus_empty(cpumask))) > > return; > > +#endif > > > > /* > > * i'm not happy about this global shared spinlock in the > > Fair enough. > > The code you're touching in with the original CPU-hotplug-for-i386 patches. > > x86_64 doesn't do it. It handles tlb flushing differently anyway. But I > suspect that x86_64 is just buggy, unless all callers of flush_tlb_others() > have taken care to disable preemption prior to their calculation of the > passed-in cpumask. > > Shudder. Gautham, this is code which we can cheerfully delete when we get > the freezer stuff done. Fortunately, Anil's patch will make it nice and > easy to find again.
Ok, I will make a note of this one. If the IO-test results are good, I hope to post the patchset sometime this week. Thanks and Regards gautham. -- Gautham R Shenoy Linux Technology Center IBM India. "Freedom comes with a price tag of responsibility, which is still a bargain, because Freedom is priceless!" - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
