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

Mike Travis
2009-11-16T21:34:16Z

Ingo Molnar wrote:
> * Mike Travis <travis@sgi.com> 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