| Message ID | 20191011134500.235736-3-douglas.raillard@arm.com (mailing list archive) |
|---|---|
| State | RFC, archived |
| Headers | show |
| Series | sched/cpufreq: Make schedutil energy aware | expand |
On 11/10/2019 15:44, Douglas RAILLARD wrote: [...] > @@ -66,6 +70,38 @@ static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu); > > /************************ Governor internals ***********************/ > > +#ifdef CONFIG_ENERGY_MODEL > +static void sugov_policy_attach_pd(struct sugov_policy *sg_policy) > +{ > + struct em_perf_domain *pd; > + struct cpufreq_policy *policy = sg_policy->policy; Shouldn't always order local variable declarations from longest to shortest line? > + > + sg_policy->pd = NULL; > + pd = em_cpu_get(policy->cpu); > + if (!pd) > + return; > + > + if (cpumask_equal(policy->related_cpus, to_cpumask(pd->cpus))) > + sg_policy->pd = pd; > + else > + pr_warn("%s: Not all CPUs in schedutil policy %u share the same perf domain, no perf domain for that policy will be registered\n", > + __func__, policy->cpu); Maybe {} because of 2 lines? > +} > + > +static struct em_perf_domain *sugov_policy_get_pd( > + struct sugov_policy *sg_policy) Maybe this way? This format is already used in this file. static struct em_perf_domain * sugov_policy_get_pd(struct sugov_policy *sg_policy) > +{ > + return sg_policy->pd; > +} > +#else /* CONFIG_ENERGY_MODEL */ > +static void sugov_policy_attach_pd(struct sugov_policy *sg_policy) {} > +static struct em_perf_domain *sugov_policy_get_pd( > + struct sugov_policy *sg_policy) > +{ > + return NULL; > +} > +#endif /* CONFIG_ENERGY_MODEL */ > + > static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) > { > s64 delta_ns; > @@ -859,6 +895,9 @@ static int sugov_start(struct cpufreq_policy *policy) > sugov_update_shared : > sugov_update_single); > } > + > + sugov_policy_attach_pd(sg_policy); > + > return 0; > } A sugov_policy_detach_pd() called from sugov_stop() (doing for instance the g_policy->pd = NULL) is not needed?
Hi Dietmar, On 10/17/19 9:57 AM, Dietmar Eggemann wrote: > On 11/10/2019 15:44, Douglas RAILLARD wrote: > > [...] > >> @@ -66,6 +70,38 @@ static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu); >> >> /************************ Governor internals ***********************/ >> >> +#ifdef CONFIG_ENERGY_MODEL >> +static void sugov_policy_attach_pd(struct sugov_policy *sg_policy) >> +{ >> + struct em_perf_domain *pd; >> + struct cpufreq_policy *policy = sg_policy->policy; > > Shouldn't always order local variable declarations from longest to > shortest line? Can't find any reference to that rule in the coding style, although I'm happy to change order if that's deemed useful. > >> + >> + sg_policy->pd = NULL; >> + pd = em_cpu_get(policy->cpu); >> + if (!pd) >> + return; >> + >> + if (cpumask_equal(policy->related_cpus, to_cpumask(pd->cpus))) >> + sg_policy->pd = pd; >> + else >> + pr_warn("%s: Not all CPUs in schedutil policy %u share the same perf domain, no perf domain for that policy will be registered\n", >> + __func__, policy->cpu); > > Maybe {} because of 2 lines? +1 >> +} >> + >> +static struct em_perf_domain *sugov_policy_get_pd( >> + struct sugov_policy *sg_policy) > > > Maybe this way? This format is already used in this file. > > static struct em_perf_domain * > sugov_policy_get_pd(struct sugov_policy *sg_policy) > I also prefer this kind of non-indented form that always stays indented across renames :) >> +{ >> + return sg_policy->pd; >> +} >> +#else /* CONFIG_ENERGY_MODEL */ >> +static void sugov_policy_attach_pd(struct sugov_policy *sg_policy) {} >> +static struct em_perf_domain *sugov_policy_get_pd( >> + struct sugov_policy *sg_policy) >> +{ >> + return NULL; >> +} >> +#endif /* CONFIG_ENERGY_MODEL */ >> + >> static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) >> { >> s64 delta_ns; >> @@ -859,6 +895,9 @@ static int sugov_start(struct cpufreq_policy *policy) >> sugov_update_shared : >> sugov_update_single); >> } >> + >> + sugov_policy_attach_pd(sg_policy); >> + >> return 0; >> } > > A sugov_policy_detach_pd() called from sugov_stop() (doing for instance > the g_policy->pd = NULL) is not needed? From what I could see, sugov_stop() will always be followed by sugov_start() before it's used again, so that does not seem more risky than not de-initializing sg_cpu's for example.
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index ba9e8309eec7..9abda58827c0 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -42,6 +42,10 @@ struct sugov_policy { bool limits_changed; bool need_freq_update; + +#ifdef CONFIG_ENERGY_MODEL + struct em_perf_domain *pd; +#endif }; struct sugov_cpu { @@ -66,6 +70,38 @@ static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu); /************************ Governor internals ***********************/ +#ifdef CONFIG_ENERGY_MODEL +static void sugov_policy_attach_pd(struct sugov_policy *sg_policy) +{ + struct em_perf_domain *pd; + struct cpufreq_policy *policy = sg_policy->policy; + + sg_policy->pd = NULL; + pd = em_cpu_get(policy->cpu); + if (!pd) + return; + + if (cpumask_equal(policy->related_cpus, to_cpumask(pd->cpus))) + sg_policy->pd = pd; + else + pr_warn("%s: Not all CPUs in schedutil policy %u share the same perf domain, no perf domain for that policy will be registered\n", + __func__, policy->cpu); +} + +static struct em_perf_domain *sugov_policy_get_pd( + struct sugov_policy *sg_policy) +{ + return sg_policy->pd; +} +#else /* CONFIG_ENERGY_MODEL */ +static void sugov_policy_attach_pd(struct sugov_policy *sg_policy) {} +static struct em_perf_domain *sugov_policy_get_pd( + struct sugov_policy *sg_policy) +{ + return NULL; +} +#endif /* CONFIG_ENERGY_MODEL */ + static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) { s64 delta_ns; @@ -859,6 +895,9 @@ static int sugov_start(struct cpufreq_policy *policy) sugov_update_shared : sugov_update_single); } + + sugov_policy_attach_pd(sg_policy); + return 0; }
Attach an Energy Model perf_domain to each sugov_policy to prepare the ground for energy-aware schedutil. Signed-off-by: Douglas RAILLARD <douglas.raillard@arm.com> --- kernel/sched/cpufreq_schedutil.c | 39 ++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)