DragonFly-2.3.0.864.gc5b83 master sys/platform/pc32/apic mpapic.c sys/platform/pc32/isa clock.c sys/platform/pc64/isa clock.c sys/platform/vkernel/platform systimer.c sys/sys systimer.h
Sepherosa Ziehau
sepherosa at gmail.com
Mon May 4 18:44:26 PDT 2009
On Mon, May 4, 2009 at 11:29 PM, Matthew Dillon
<dillon at apollo.backplane.com> wrote:
>
> :> Then on entry to C3/C1E the ACPI code could explicitly call
> :> cputimer_intr_sleep_reload(), and on exit it could explicitly
> :
> :Implicitly?
> :
> :> resynchronize the LAPIC like it does already (I think).
>
> It may not be relevant if you are going to change the
> acpi_cpu_idle() code to just leave the LAPIC installed as
> the official cpu timer instead of calling cputimer_intr_switch()
> to switch things back and forth.
To be safe, we will have to do an explicit reload :)
>
> For an 8254-based wakeup you would probably want to maintain
> a global cpu mask of cpu's sitting in sleep that need to be
> IPId (instead of IPI'ing all of them), and interlock the updating
> of the 8254's one-shot & notification cpumask with the same spinlock
> the 8254 code uses now (clock_lock()).
Would it necessary to use clock_lock()? I think if the mask is only
set/clear in acpi_idle, atomic operation should be enough.
>
> There are a lot of things that could be causing excessive interrupts
> on a multi-cpu platform, the code is going to be quite sensitive.
>
> -Matt
> Matthew Dillon
> <dillon at backplane.com>
>
--
Live Free or Die
More information about the Commits
mailing list