Re: [PATCH v3 1/4] ACPI: Add acpi_pr_<level>() interfaces

[Toshi Kani <toshi.kani@hp.com>]

On Thu, 2012-07-26 at 14:57 -0700, Joe Perches wrote:
> On Thu, 2012-07-26 at 15:50 -0600, Bjorn Helgaas wrote:
> > On Thu, Jul 26, 2012 at 3:43 PM, Joe Perches <joe@perches.com> wrote:
> > > On Thu, 2012-07-26 at 15:37 -0600, Bjorn Helgaas wrote:
> > >>     PNP0C01:00: new device for \_SB_.PCI0.ISA_.MBIO
> > >>
> > >> I fiddled with this a while ago; it would look something like this:
> > > []
> > >> +static noinline_for_stack
> > >> +char *acpi_name_string(char *buf, char *end, acpi_handle handle,
> > >> +                    struct printf_spec spec, const char *fmt)
> []
> > Yes.  I'm hesitant about this approach in general, because I don't
> > think printing the ACPI path is something we should be doing often.
> > It's not like a struct resource or a MAC address, where there are
> > dozens or hundreds of users.  I really think we should only print ACPI
> > paths in one or two places, so adding a %p extension would waste a
> > letter and encourage the wrong behavior.
> 
> I don't much care for adding ACPI specific calls to vsprintf
> as acpi is supposed to be OS generic anyway.
> 
> I don't think there's anything wrong with Toshi's approach.
> Anyone that looks for speed in a logging message is looking
> for an oddly fitting thing.  Tracing sure, but logging?

Fully agreed!  One cannot use printk in performance path.

Thanks,
-Toshi


> I also don't see anything wrong with renaming it to just
> acpi_<level>, but that's a different discussion.
> 
> cheers, Joe
> 
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