Messages in this thread Patch in this message | | | Date | Mon, 4 Apr 2022 17:01:45 +0100 | From | Ionela Voinescu <> | Subject | Re: [RESEND][PATCH 3/8] PM: EM: Use the new .get_cost() callback while registering EM |
| |
Hi Lukasz,
On Monday 21 Mar 2022 at 09:57:24 (+0000), Lukasz Luba wrote: > The Energy Model (EM) allows to provide the 'cost' values when the device > driver provides the .get_cost() optional callback. This removes > restriction which is in the EM calculation function of the 'cost' > for each performance state. Now, the driver is in charge of providing > the right values which are then used by Energy Aware Scheduler. > > Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> > --- > kernel/power/energy_model.c | 39 ++++++++++++++++++++++++++----------- > 1 file changed, 28 insertions(+), 11 deletions(-) > > diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c > index 6ecee99af842..95a3b33001f6 100644 > --- a/kernel/power/energy_model.c > +++ b/kernel/power/energy_model.c > @@ -121,7 +121,8 @@ static void em_debug_remove_pd(struct device *dev) {} > #endif > > static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, > - int nr_states, struct em_data_callback *cb) > + int nr_states, struct em_data_callback *cb, > + unsigned long flags) > { > unsigned long power, freq, prev_freq = 0, prev_cost = ULONG_MAX; > struct em_perf_state *table; > @@ -173,10 +174,22 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, > /* Compute the cost of each performance state. */ > fmax = (u64) table[nr_states - 1].frequency; > for (i = nr_states - 1; i >= 0; i--) { > - unsigned long power_res = em_scale_power(table[i].power); > + unsigned long power_res, cost; > + > + if (flags & EM_PERF_DOMAIN_ARTIFICIAL) { > + ret = cb->get_cost(dev, table[i].frequency, &cost); > + if (ret || !cost || cost > EM_MAX_POWER) { > + dev_err(dev, "EM: invalid cost %lu %d\n", > + cost, ret); > + goto free_ps_table; > + } > + } else { > + power_res = em_scale_power(table[i].power); > + cost = div64_u64(fmax * power_res, table[i].frequency); > + } > + > + table[i].cost = cost; > > - table[i].cost = div64_u64(fmax * power_res, > - table[i].frequency); > if (table[i].cost >= prev_cost) { > table[i].flags = EM_PERF_STATE_INEFFICIENT; > dev_dbg(dev, "EM: OPP:%lu is inefficient\n", > @@ -197,7 +210,8 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, > } > > static int em_create_pd(struct device *dev, int nr_states, > - struct em_data_callback *cb, cpumask_t *cpus) > + struct em_data_callback *cb, cpumask_t *cpus, > + unsigned long flags) > { > struct em_perf_domain *pd; > struct device *cpu_dev; > @@ -215,7 +229,7 @@ static int em_create_pd(struct device *dev, int nr_states, > return -ENOMEM; > } > > - ret = em_create_perf_table(dev, pd, nr_states, cb); > + ret = em_create_perf_table(dev, pd, nr_states, cb, flags); > if (ret) { > kfree(pd); > return ret; > @@ -332,6 +346,7 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, > bool milliwatts) > { > unsigned long cap, prev_cap = 0; > + unsigned long flags = 0; > int cpu, ret; > > if (!dev || !nr_states || !cb) > @@ -378,14 +393,16 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, > } > } > > - ret = em_create_pd(dev, nr_states, cb, cpus); > + if (milliwatts) > + flags |= EM_PERF_DOMAIN_MILLIWATTS; > + else if (cb->get_cost) > + flags |= EM_PERF_DOMAIN_ARTIFICIAL; > + > + ret = em_create_pd(dev, nr_states, cb, cpus, flags); > if (ret) > goto unlock; > > - if (milliwatts) > - dev->em_pd->flags |= EM_PERF_DOMAIN_MILLIWATTS; > - else if (cb->get_cost) > - dev->em_pd->flags |= EM_PERF_DOMAIN_ARTIFICIAL; > + dev->em_pd->flags |= flags; >
nit: given that there is a designated function to create the PD which now requires information on flags to initilise the domains properly, might be better to have dev->em_pd->flags set inside that function, rather than here.
> em_cpufreq_update_efficiencies(dev); >
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Thanks, Ionela.
> -- > 2.17.1 >
| |