Re: [PATCH 1/6] x86: Limit the number of processor bootup messages

[Mike Travis]

Ingo Molnar wrote:
> * Mike Travis <travis@xxxxxxx> wrote:
>
> > +	if (cpu == 0)
> > +		printk(KERN_INFO "CPU0: Thermal monitoring enabled (%s)\n",
> > +		       tm2 ? "TM2" : "TM1");
>
> Hm, 'cpu==0 means boot cpu' assumptions are not particularly clean.

Yes.  It appears that boot_cpu_id is only defined for x86.  I don't know
any other way to identify the boot cpu.  (Hmm, in this case it *is* an
x86 specific function, so I'll change it.)

> > +#ifdef CONFIG_NUMA
> > +	if (system_state == SYSTEM_BOOTING) {
> > +		static int current_node = -1;
> > +		int node = cpu_to_node(cpu);
> > +
> > +		if (node != current_node) {
> > +			if (current_node > (-1))
> > +				pr_cont(" Ok.\n");
> > +			current_node = node;
> > +			pr_info("Booting Node %3d, Processors ", node);
> > +		}
> > +		pr_cont(" #%d%s", cpu, cpu == (nr_cpu_ids - 1) ? " Ok.\n" : "");
> > +	} else
> > +#endif
> > +		pr_info("Booting Processor %d APIC 0x%x\n", cpu, apicid);
>
> preprocessor directives cutting into if/else branches in an assymetric 
> way is being frowned upon. I'd also suggest to put this into a helper 
> inline.

ok.

> Is the SYSTEM_BOOTING check there to not re-print this on CPU hotplug?

Actually you get the old style "Booting Processor" message for hotplug off/on.

newton:~ # cd /sys/devices/system/cpu
newton:/sys/devices/system/cpu # echo 0 > cpu6/online
[ 3037.593411] CPU 6 is now offline

newton:/sys/devices/system/cpu # echo 1 > cpu6/online
[ 3045.843469] Booting Processor 6 APIC 0x3

I can't test going into/out of the sleep modes, so it may be better to
summarize for those operations as well.

Thanks,
Mike

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