On Wed, Feb 21, 2024 at 8:49 PM Vilas Bhat <[email protected]> wrote: > > Existing runtime PM ftrace events (`rpm_suspend`, `rpm_resume`, > `rpm_return_int`) offer limited visibility into the exact timing of device > runtime power state transitions, particularly when asynchronous operations > are involved. When the `rpm_suspend` or `rpm_resume` functions are invoked > with the `RPM_ASYNC` flag, a return value of 0 i.e., success merely > indicates that the device power state request has been queued, not that > the device has yet transitioned. > > A new ftrace event, `rpm_status`, is introduced. This event directly logs > the `power.runtime_status` value of a device whenever it changes providing > granular tracking of runtime power state transitions regardless of > synchronous or asynchronous `rpm_suspend` / `rpm_resume` usage. > > Signed-off-by: Vilas Bhat <[email protected]> > --- > V1 -> V2: Modified enum value definition as per reviewer comments. > --- > drivers/base/power/runtime.c | 1 + > include/trace/events/rpm.h | 42 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 43 insertions(+) > > diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c > index 05793c9fbb84..d10354847878 100644 > --- a/drivers/base/power/runtime.c > +++ b/drivers/base/power/runtime.c > @@ -94,6 +94,7 @@ static void update_pm_runtime_accounting(struct device *dev) > static void __update_runtime_status(struct device *dev, enum rpm_status > status) > { > update_pm_runtime_accounting(dev); > + trace_rpm_status(dev, status); > dev->power.runtime_status = status; > } > > diff --git a/include/trace/events/rpm.h b/include/trace/events/rpm.h > index 3c716214dab1..bd120e23ce12 100644 > --- a/include/trace/events/rpm.h > +++ b/include/trace/events/rpm.h > @@ -101,6 +101,48 @@ TRACE_EVENT(rpm_return_int, > __entry->ret) > ); > > +#define RPM_STATUS_STRINGS \ > + EM(RPM_INVALID, "RPM_INVALID") \ > + EM(RPM_ACTIVE, "RPM_ACTIVE") \ > + EM(RPM_RESUMING, "RPM_RESUMING") \ > + EM(RPM_SUSPENDED, "RPM_SUSPENDED") \ > + EMe(RPM_SUSPENDING, "RPM_SUSPENDING") > + > +/* Enums require being exported to userspace, for user tool parsing. */ > +#undef EM > +#undef EMe > +#define EM(a, b) TRACE_DEFINE_ENUM(a); > +#define EMe(a, b) TRACE_DEFINE_ENUM(a); > + > +RPM_STATUS_STRINGS > + > +/* > + * Now redefine the EM() and EMe() macros to map the enums to the strings > that > + * will be printed in the output. > + */ > +#undef EM > +#undef EMe > +#define EM(a, b) { a, b }, > +#define EMe(a, b) { a, b } > + > +TRACE_EVENT(rpm_status, > + TP_PROTO(struct device *dev, enum rpm_status status), > + TP_ARGS(dev, status), > + > + TP_STRUCT__entry( > + __string(name, dev_name(dev)) > + __field(int, status) > + ), > + > + TP_fast_assign( > + __assign_str(name, dev_name(dev)); > + __entry->status = status; > + ), > + > + TP_printk("%s status=%s", __get_str(name), > + __print_symbolic(__entry->status, RPM_STATUS_STRINGS)) > +); > + > #endif /* _TRACE_RUNTIME_POWER_H */ > > /* This part must be outside protection */ > --
Applied as 6.9 material, thanks!
