On Wednesday, June 20, 2018 7:22:08 PM CEST Ulf Hansson wrote: > CPU devices and other regular devices may share the same PM domain and may > also be hierarchically related via subdomains. In either case, all devices > including CPUs, may be attached to a PM domain managed by genpd, that has > an idle state with an enter/exit latency. > > Let's take these latencies into account in the state selection process by > genpd's governor for CPUs. This means the governor, pm_domain_cpu_gov, > becomes extended to satisfy both a state's residency and a potential dev PM > QoS constraint. > > Cc: Lina Iyer <[email protected]> > Co-developed-by: Lina Iyer <[email protected]> > Signed-off-by: Ulf Hansson <[email protected]> > --- > drivers/base/power/domain_governor.c | 15 +++++++++++---- > include/linux/pm_domain.h | 1 + > 2 files changed, 12 insertions(+), 4 deletions(-) > > diff --git a/drivers/base/power/domain_governor.c > b/drivers/base/power/domain_governor.c > index 1aad55719537..03d4e9454ce9 100644 > --- a/drivers/base/power/domain_governor.c > +++ b/drivers/base/power/domain_governor.c > @@ -214,8 +214,10 @@ static bool default_power_down_ok(struct dev_pm_domain > *pd) > struct generic_pm_domain *genpd = pd_to_genpd(pd); > struct gpd_link *link; > > - if (!genpd->max_off_time_changed) > + if (!genpd->max_off_time_changed) { > + genpd->state_idx = genpd->cached_power_down_state_idx; > return genpd->cached_power_down_ok; > + } > > /* > * We have to invalidate the cached results for the masters, so > @@ -240,6 +242,7 @@ static bool default_power_down_ok(struct dev_pm_domain > *pd) > genpd->state_idx--; > } > > + genpd->cached_power_down_state_idx = genpd->state_idx; > return genpd->cached_power_down_ok; > } > > @@ -255,6 +258,10 @@ static bool cpu_power_down_ok(struct dev_pm_domain *pd) > s64 idle_duration_ns; > int cpu, i; > > + /* Validate dev PM QoS constraints. */ > + if (!default_power_down_ok(pd)) > + return false; > + > if (!(genpd->flags & GENPD_FLAG_CPU_DOMAIN)) > return true; > > @@ -276,9 +283,9 @@ static bool cpu_power_down_ok(struct dev_pm_domain *pd) > /* > * Find the deepest idle state that has its residency value satisfied > * and by also taking into account the power off latency for the state. > - * Start at the deepest supported state. > + * Start at the state picked by the dev PM QoS constraint validation. > */ > - i = genpd->state_count - 1; > + i = genpd->state_idx; > do { > if (!genpd->states[i].residency_ns) > break; > @@ -312,6 +319,6 @@ struct dev_power_governor pm_domain_always_on_gov = { > }; > > struct dev_power_governor pm_domain_cpu_gov = { > - .suspend_ok = NULL, > + .suspend_ok = default_suspend_ok, > .power_down_ok = cpu_power_down_ok, > }; > diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h > index 97901c833108..dbc69721cad8 100644 > --- a/include/linux/pm_domain.h > +++ b/include/linux/pm_domain.h > @@ -81,6 +81,7 @@ struct generic_pm_domain { > s64 max_off_time_ns; /* Maximum allowed "suspended" time. */ > bool max_off_time_changed; > bool cached_power_down_ok; > + bool cached_power_down_state_idx; > int (*attach_dev)(struct generic_pm_domain *domain, > struct device *dev); > void (*detach_dev)(struct generic_pm_domain *domain, >
I don't see much value in splitting this patch off [07/26] and it actually confused me, so it may as well confuse someone else.
