Re: [PATCH v8 3/6] cpufreq: powernv: Remove cpu_to_chip_id() from hot-path

On Sat, 2016-03-19 at 09:37 +1100, Benjamin Herrenschmidt wrote:

On Fri, 2016-03-18 at 15:04 +1100, Michael Neuling wrote:

quoted

=20
 static int nr_chips;
+static DEFINE_PER_CPU(unsigned int, chip_id);
=20
 /*
  * Note: The set of pstates consists of contiguous integers, the

@@ -317,9 +318,7 @@ static void powernv_cpufreq_throttle_check(void

*data)
=20
        pmsr =3D get_pmspr(SPRN_PMSR);
=20
-       for (i =3D 0; i < nr_chips; i++)
-               if (chips[i].id =3D=3D cpu_to_chip_id(cpu))
-                       break;
+       i =3D this_cpu_read(chip_id);

=20
Except it's not a chip_id, so your patch confused me for a good 2mn
...
Call it chip_idx maybe ? ie, index.

Yeah, it was a badly named variable but I changed it even more and
Shilpasri rebased it here:

http://patchwork.ozlabs.org/patch/599523/

Mikey