Re: [PATCH v3] PM / Domains: enable domain idle state accounting

[Lina Iyer <ilina@codeaurora.org>]

On Fri, Oct 16 2020 at 09:55 -0600, Rafael J. Wysocki wrote:
>On Thu, Oct 15, 2020 at 10:47 PM Lina Iyer <ilina@codeaurora.org> wrote:
>>
>> To enable better debug of PM domains, let's keep a track of the success
>> and rejections in entering each domain idle state.
>>
>> This statistics is exported in debugfs when reading the idle_states
>> node, associated with each PM domain.
>>
>> Signed-off-by: Lina Iyer <ilina@codeaurora.org>
>> ---
>> Changes in v3:
>>         - Rebased on top of mainline
>
>I still needed to rebase it to apply it to my tree, so please double
>check the result in the bleeding-edge branch.
>
Okay, will rebase on that branch and post shortly.
Thanks Rafael.

>Thanks!
>
>> ---
>>  drivers/base/power/domain.c | 10 +++++++---
>>  include/linux/pm_domain.h   |  2 ++
>>  2 files changed, 9 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
>> index 2cb5e04cf86c..20ecc1a7113c 100644
>> --- a/drivers/base/power/domain.c
>> +++ b/drivers/base/power/domain.c
>> @@ -559,12 +559,15 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
>>                  * happen very often).
>>                  */
>>                 ret = _genpd_power_off(genpd, true);
>> -               if (ret)
>> +               if (ret) {
>> +                       genpd->states[genpd->state_idx].rejected++;
>>                         return ret;
>> +               }
>>         }
>>
>>         genpd->status = GPD_STATE_POWER_OFF;
>>         genpd_update_accounting(genpd);
>> +       genpd->states[genpd->state_idx].usage++;
>>
>>         list_for_each_entry(link, &genpd->child_links, child_node) {
>>                 genpd_sd_counter_dec(link->parent);
>> @@ -2932,7 +2935,7 @@ static int idle_states_show(struct seq_file *s, void *data)
>>         if (ret)
>>                 return -ERESTARTSYS;
>>
>> -       seq_puts(s, "State          Time Spent(ms)\n");
>> +       seq_puts(s, "State          Time Spent(ms) Usage          Rejected\n");
>>
>>         for (i = 0; i < genpd->state_count; i++) {
>>                 ktime_t delta = 0;
>> @@ -2944,7 +2947,8 @@ static int idle_states_show(struct seq_file *s, void *data)
>>
>>                 msecs = ktime_to_ms(
>>                         ktime_add(genpd->states[i].idle_time, delta));
>> -               seq_printf(s, "S%-13i %lld\n", i, msecs);
>> +               seq_printf(s, "S%-13i %-14lld %-14llu %llu\n", i, msecs,
>> +                             genpd->states[i].usage, genpd->states[i].rejected);
>>         }
>>
>>         genpd_unlock(genpd);
>> diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
>> index ee11502a575b..1d9a8de6b7ac 100644
>> --- a/include/linux/pm_domain.h
>> +++ b/include/linux/pm_domain.h
>> @@ -82,6 +82,8 @@ struct genpd_power_state {
>>         s64 power_off_latency_ns;
>>         s64 power_on_latency_ns;
>>         s64 residency_ns;
>> +       u64 usage;
>> +       u64 rejected;
>>         struct fwnode_handle *fwnode;
>>         ktime_t idle_time;
>>         void *data;
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
>> a Linux Foundation Collaborative Project
>>