Re: [PATCH v8 4/4] nmi_backtrace: generate one-line reports for idle cpus

[Chris Metcalf]

On 8/18/2016 11:12 AM, Petr Mladek wrote:
> On Tue 2016-08-16 15:50:24, Chris Metcalf wrote:
> > [...]
> > -static inline void native_safe_halt(void)
> > +static __always_inline void native_safe_halt(void)
> >   {
> >   	asm volatile("sti; hlt": : :"memory");
> >   }
> Ah, the __always_inline stuff did not helped here. It was
> not inlined:
>
> $> nm -n vmlinux | grep native_safe_halt
> ffffffff81050bc0 t native_safe_halt
>
> The reason seems to be that it is called via
> PVOP_VCALL0(pv_irq_ops.safe_halt);, see below
> in the disassembly.
>
> I guess that it is because I have
> CONFIG_PARAVIRT=y

I fixed this by reverting to using __cpuidle instead of __always_inline.
As you discovered, we can't use <linux/cpu.h> here, but I chose to
just duplicate the #define of __cpuidle in <asm/irqflags.h> instead
since I think that's cleaner.

--
Chris Metcalf, Mellanox Technologies
http://www.mellanox.com