Re: [PATCH v8 3/6] cpufreq: powernv: Remove cpu_to_chip_id() from hot-path
From: Benjamin Herrenschmidt <hidden>
Date: 2016-03-18 22:38:25
Also in:
linux-pm, lkml
On Fri, 2016-03-18 at 15:04 +1100, Michael Neuling wrote:
quoted hunk ↗ jump to hunk
static int nr_chips; +static DEFINE_PER_CPU(unsigned int, chip_id); /* * Note: The set of pstates consists of contiguous integers, the@@ -317,9 +318,7 @@ static void powernv_cpufreq_throttle_check(void*data) pmsr = get_pmspr(SPRN_PMSR); - for (i = 0; i < nr_chips; i++) - if (chips[i].id == cpu_to_chip_id(cpu)) - break; + i = this_cpu_read(chip_id);
Except it's not a chip_id, so your patch confused me for a good 2mn ... Call it chip_idx maybe ? ie, index. Cheers, Ben.
quoted hunk ↗ jump to hunk
/* Check for Pmax Capping */ pmsr_pmax = (s8)PMSR_MAX(pmsr);@@ -560,6 +559,7 @@ static int init_chip_info(void)for_each_possible_cpu(cpu) { unsigned int id = cpu_to_chip_id(cpu); + per_cpu(chip_id, cpu) = nr_chips; if (prev_chip_id != id) { prev_chip_id = id; chip[nr_chips++] = id; _______________________________________________