On Thu, 13 Dec 2007 23:33:07 +0100 Andi Kleen <[EMAIL PROTECTED]> wrote:
> The description/option is not correct. The mainline kernel never > disables C1e. Some distribution kernels and Xen do, perhaps you're > confusing this with them. > > You would rather need a "force_disable_c1e" option if anything. The option I added (which is set to Y by default, but that's another matter) disables C1E without any other kernel parameter. In my opinion, this should be the normal behavior: the kernel has both SMP and NO_HZ enabled, so do whatever is necessary to enable dynticks. But it would also be useful, for benchmarking purposes, to prevent the kernel from disabling C1E using a kernel parameter; that's what force_amd_c1e does. > Anyways this should be near all obsolete with forced HPET. With HPET > dynticks can be used even with C1e. So in most cases you can just > use hpet=force instead and get dynticks and C1e together. On my system, hpet=force does not enable dynticks: $ dmesg | grep -E "(not functional|hpet)" Command line: ro hpet=force Kernel command line: ro hpet=force hpet clockevent registered hpet0: at MMIO 0xfed00000, IRQs 2, 8, 31 hpet0: 3 32-bit timers, 25000000 Hz Time: hpet clocksource has been installed. Clockevents: could not switch to one-shot mode: lapic is not functional. Clockevents: could not switch to one-shot mode: lapic is not functional. hpet_resources: 0xfed00000 is busy But, using this patch, the kernel enables dynticks. -- 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/