On Wed, 2019-03-27 at 11:38 +0200, Leon Romanovsky wrote:
> On Wed, Mar 27, 2019 at 02:17:40AM -0700, Joe Perches wrote:
> > On Wed, 2019-03-27 at 11:09 +0200, Leon Romanovsky wrote:
> > > Kernel is booted with less possible CPUs (possible_cpus kernel boot
> > > option) than available CPUs will have prints like this:
> > []
> > > diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
> > []
> > > @@ -2305,9 +2305,9 @@ int generic_processor_info(int apicid, int version)
> > > if (num_processors >= nr_cpu_ids) {
> > > int thiscpu = max + disabled_cpus;
> > >
> > > - pr_warning("APIC: NR_CPUS/possible_cpus limit of %i "
> > > - "reached. Processor %d/0x%x ignored.\n",
> > > - max, thiscpu, apicid);
> > > + pr_debug(
> > > + "APIC: NR_CPUS/possible_cpus limit of %i reached.
> > > Processor %d/0x%x ignored.\n",
> > > + max, thiscpu, apicid);
> >
> > 2 lines please
> >
> > pr_debug("APIC: etc...",
> > max, thiscpu, ...);
>
> It was two lines before, but I changed for two reasons:
> * It helped me to grep the source code to find the origin of dmesg warning.
> * i got checkpatch warning about spitted string, can you please fix
> checkpatch do not complain?
Yes, use
pr_debug("APIC: NR_CPUS/possible_cpus limit of %i reached. Processor
%d/0x%x ignored.\n",
max, thiscpu, apicid);
or better
printk(KERN_DEBUG "APIC: NR_CPUS/possible_cpus limit of %i reached.
Processor %d/0x%x ignored.\n",
max, thiscpu, apicid);
> > And this would probably be better as
> >
> > printk(KERN_DEBUG "APIC: etc...",
> > ...)
> >
> > to avoid the need to compile with DEBUG or enable
> > with CONFIG_DYNAMIC_DEBUG
>
> You don't need anything like this, just provide dyndbg parameters
> through kernel command line.
That assumes CONFIG_DYNAMIC_DEBUG is always enabled,
and it is not enabled in many .config files.
