Re: [PATCH v3 6/6] cpufreq: powernv: Restore cpu frequency to policy->cur on unthrottling

Preeti U Murthy
2015-05-05T09:40:10Z

On 05/04/2015 02:24 PM, Shilpasri G Bhat wrote:
> If frequency is throttled due to OCC reset then cpus will be in Psafe
> frequency, so restore the frequency on all cpus to policy->cur when
> OCCs are active again. And if frequency is throttled due to Pmax
> capping then restore the frequency of all the cpus in the chip on
> unthrottling.
>
> Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
> ---
> drivers/cpufreq/powernv-cpufreq.c | 31 +++++++++++++++++++++++++++++--
> 1 file changed, 29 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
> index 0a59d5b..b2915bc 100644
> --- a/drivers/cpufreq/powernv-cpufreq.c
> +++ b/drivers/cpufreq/powernv-cpufreq.c
> @@ -51,6 +51,7 @@ static struct chip {
> bool throttled;
> cpumask_t mask;
> struct work_struct throttle;
> + bool restore;
> } *chips;
>
> static int nr_chips;
> @@ -418,9 +419,29 @@ static struct notifier_block powernv_cpufreq_reboot_nb = {
> void powernv_cpufreq_work_fn(struct work_struct *work)
> {
> struct chip *chip = container_of(work, struct chip, throttle);
> + unsigned int cpu;
> + cpumask_var_t mask;
>
> smp_call_function_any(&chip->mask,
> powernv_cpufreq_throttle_check, NULL, 0);
> +
> + if (!chip->restore)
> + return;
> +
> + chip->restore = false;
> + cpumask_copy(mask, &chip->mask);
> + for_each_cpu_and(cpu, mask, cpu_online_mask) {
> + int index, tcpu;
> + struct cpufreq_policy policy;
> +
> + cpufreq_get_policy(&policy, cpu);
> + cpufreq_frequency_table_target(&policy, policy.freq_table,
> + policy.cur,
> + CPUFREQ_RELATION_C, &index);
> + powernv_cpufreq_target_index(&policy, index);
> + for_each_cpu(tcpu, policy.cpus)
> + cpumask_clear_cpu(tcpu, mask);
> + }
> }
>
> static char throttle_reason[][30] = {
> @@ -473,8 +494,10 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
> throttled = false;
> pr_info("OCC: Active\n");
>
> - for (i = 0; i < nr_chips; i++)
> + for (i = 0; i < nr_chips; i++) {
> + chips[i].restore = true;
> schedule_work(&chips[i].throttle);
> + }
>
> return 0;
> }
> @@ -490,8 +513,11 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
> return 0;
>
> for (i = 0; i < nr_chips; i++)
> - if (chips[i].id == chip_id)
> + if (chips[i].id == chip_id) {
> + if (!reason)
> + chips[i].restore = true;
> schedule_work(&chips[i].throttle);
> + }
> }
> return 0;
> }
> @@ -545,6 +571,7 @@ static int init_chip_info(void)
> chips[i].throttled = false;
> cpumask_copy(&chips[i].mask, cpumask_of_node(chip[i]));
> INIT_WORK(&chips[i].throttle, powernv_cpufreq_work_fn);
> + chips[i].restore = false;
> }
>
> return 0;
>

Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>