>I enabled CPU hotplug and preemptible debugging... now I get...
>
>BUG: using smp_processor_id() in preemptible [00000001] code:
>swapper/0
>caller is acpi_processor_idle+0xb/0x235
> [<c020ba28>] smp_processor_id+0xa8/0xc0
> [<c02338ce>] acpi_processor_idle+0xb/0x235
> [<c02338c3>] acpi_processor_idle+0x0/0x235
> [<c02338ce>] acpi_processor_idle+0xb/0x235
> [<c02338c3>] acpi_processor_idle+0x0/0x235
> [<c02338c3>] acpi_processor_idle+0x0/0x235
> [<c02338c3>] acpi_processor_idle+0x0/0x235
> [<c0101115>] cpu_idle+0x75/0x110
> [<c04f5988>] start_kernel+0x158/0x180
> [<c04f5390>] unknown_bootoption+0x0/0x1e0
It doesn't trouble to me. It's in idle thread.
Thanks,
Shaohua
Hi!
> >I enabled CPU hotplug and preemptible debugging... now I get...
> >
> >BUG: using smp_processor_id() in preemptible [00000001] code:
> >swapper/0
> >caller is acpi_processor_idle+0xb/0x235
> > [<c020ba28>] smp_processor_id+0xa8/0xc0
> > [<c02338ce>] acpi_processor_idle+0xb/0x235
> > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > [<c02338ce>] acpi_processor_idle+0xb/0x235
> > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > [<c0101115>] cpu_idle+0x75/0x110
> > [<c04f5988>] start_kernel+0x158/0x180
> > [<c04f5390>] unknown_bootoption+0x0/0x1e0
> It doesn't trouble to me. It's in idle thread.
You mean it does not happen to you? On my machine it fills logs very
quickly...
Pavel
--
People were complaining that M$ turns users into beta-testers...
...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!
On Mon, 2005-01-10 at 17:55, Pavel Machek wrote:
> > >I enabled CPU hotplug and preemptible debugging... now I get...
> > >
> > >BUG: using smp_processor_id() in preemptible [00000001] code:
> > >swapper/0
> > >caller is acpi_processor_idle+0xb/0x235
> > > [<c020ba28>] smp_processor_id+0xa8/0xc0
> > > [<c02338ce>] acpi_processor_idle+0xb/0x235
> > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > [<c02338ce>] acpi_processor_idle+0xb/0x235
> > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > [<c0101115>] cpu_idle+0x75/0x110
> > > [<c04f5988>] start_kernel+0x158/0x180
> > > [<c04f5390>] unknown_bootoption+0x0/0x1e0
> > It doesn't trouble to me. It's in idle thread.
>
> You mean it does not happen to you? On my machine it fills logs very
> quickly...
What I mean is idle thread can't be migrated so this doesn't impact the
correctness. I guess the preemptible debugging can't recognise such
situation.
Thanks,
Shaohua
Li Shaohua wrote:
> On Mon, 2005-01-10 at 17:55, Pavel Machek wrote:
>
>>>>I enabled CPU hotplug and preemptible debugging... now I get...
>>>>
>>>>BUG: using smp_processor_id() in preemptible [00000001] code:
>>>>swapper/0
>>>>caller is acpi_processor_idle+0xb/0x235
>>>>[<c020ba28>] smp_processor_id+0xa8/0xc0
>>>>[<c02338ce>] acpi_processor_idle+0xb/0x235
>>>>[<c02338c3>] acpi_processor_idle+0x0/0x235
>>>>[<c02338ce>] acpi_processor_idle+0xb/0x235
>>>>[<c02338c3>] acpi_processor_idle+0x0/0x235
>>>>[<c02338c3>] acpi_processor_idle+0x0/0x235
>>>>[<c02338c3>] acpi_processor_idle+0x0/0x235
>>>>[<c0101115>] cpu_idle+0x75/0x110
>>>>[<c04f5988>] start_kernel+0x158/0x180
>>>>[<c04f5390>] unknown_bootoption+0x0/0x1e0
>>>
>>>It doesn't trouble to me. It's in idle thread.
>>
>>You mean it does not happen to you? On my machine it fills logs very
>>quickly...
>
> What I mean is idle thread can't be migrated so this doesn't impact the
> correctness. I guess the preemptible debugging can't recognise such
> situation.
This patch should help. If it's safe to use smp_processor_id() in
acpi_processor_idle use the alternative call.
Signed-off-by: Con Kolivas <[email protected]>
On Monday 10 January 2005 08:04 pm, Li Shaohua wrote:
> On Mon, 2005-01-10 at 17:55, Pavel Machek wrote:
> > > >I enabled CPU hotplug and preemptible debugging... now I get...
> > > >
> > > >BUG: using smp_processor_id() in preemptible [00000001] code:
> > > >swapper/0
> > > >caller is acpi_processor_idle+0xb/0x235
> > > > [<c020ba28>] smp_processor_id+0xa8/0xc0
> > > > [<c02338ce>] acpi_processor_idle+0xb/0x235
> > > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > > [<c02338ce>] acpi_processor_idle+0xb/0x235
> > > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > > [<c02338c3>] acpi_processor_idle+0x0/0x235
> > > > [<c0101115>] cpu_idle+0x75/0x110
> > > > [<c04f5988>] start_kernel+0x158/0x180
> > > > [<c04f5390>] unknown_bootoption+0x0/0x1e0
> > > It doesn't trouble to me. It's in idle thread.
> >
> > You mean it does not happen to you? On my machine it fills logs very
> > quickly...
> What I mean is idle thread can't be migrated so this doesn't impact the
> correctness. I guess the preemptible debugging can't recognise such
> situation.
>
Why don't you just move that statement down, like in the patch below.
Also, if processor is not registered but idle thread managed to call
acpi_processor_idle I think it's BUG()...
I also cut out unnecessary local variable initializations.
Signed-off-by: Dmitry Torokhov <[email protected]>
--
Dmitry
===== drivers/acpi/processor.c 1.72 vs edited =====
--- 1.72/drivers/acpi/processor.c 2004-12-03 02:25:47 -05:00
+++ edited/drivers/acpi/processor.c 2005-01-10 20:58:38 -05:00
@@ -337,15 +337,11 @@
static void
acpi_processor_idle (void)
{
- struct acpi_processor *pr = NULL;
- struct acpi_processor_cx *cx = NULL;
- unsigned int next_state = 0;
- unsigned int sleep_ticks = 0;
- u32 t1, t2 = 0;
-
- pr = processors[smp_processor_id()];
- if (!pr)
- return;
+ struct acpi_processor *pr;
+ struct acpi_processor_cx *cx;
+ unsigned int next_state;
+ unsigned int sleep_ticks;
+ u32 t1, t2;
/*
* Interrupts must be disabled during bus mastering calculations and
@@ -361,6 +357,10 @@
local_irq_enable();
return;
}
+
+ pr = processors[smp_processor_id()];
+ if (!pr)
+ BUG();
cx = &(pr->power.states[pr->power.state]);