RE: NO_HZ: timer interrupt stuck [Re: Linux 2.6.21-rc1]

Pallipadi, Venkatesh
2007-02-22T19:58:22Z

>-----Original Message-----
>From: linux-kernel-owner@vger.kernel.org
>[mailto:linux-kernel-owner@vger.kernel.org] On Behalf Of
>Thomas Gleixner
>Sent: Thursday, February 22, 2007 8:00 AM
>To: Pierre Ossman
>Cc: Arjan van de Ven; Jan Engelhardt; Luca Tettamanti;
>linux-kernel@vger.kernel.org
>Subject: Re: NO_HZ: timer interrupt stuck [Re: Linux 2.6.21-rc1]
>
>On Thu, 2007-02-22 at 16:13 +0100, Pierre Ossman wrote:
>> > Sure. My dmesg is full of mmc debug crud right now, but
>I'll just reboot
>> > and I'll have a clean one for you.
>> >
>>
>> Here we go.
>
>> [ 44.498253] ACPI: Lid Switch [C136]
>> [ 44.577672] No dock devices found.
>> [ 44.714156] ACPI: CPU0 (power states: C1[C1] C2[C2] C3[C3])
>
>---------------------------------------------------------^^^^^
>
>Here is the reason. The local APIC stops working in C3 state
>and we fall
>back to the PIT in that case. Not really exciting for dynticks, but the
>only way to keep the system alive. There is a patch coming up from
>Intel, which finds out how to use HPET even if it is not enabled by the
>BIOS. This will still end up on IRQ#0, but will give way longer idle
>sleeps than the PIT.
>
> tglx
>
>

Thomas,

I have the patchset for this HPET part ready to roll out. But, looks
like
NO_HZ and lapic eventsource support is only in i386 and not in x86-64 in
2.6.21-rc1.
Do you know the state of NO_HZ x86-64 support?

Will it get into git soon? In which case I can rebase my patches against
git
and send it out for review/testing.

Otherwise, I will send out my patches, which are against rt (and my
initial
implementation of this HPET part is only for x86-64).

Thanks,
Venki