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| author | Vilas Bhat <vilasbhat@google.com> | 2024-02-21 19:47:53 +0000 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2024-02-22 20:27:39 +0100 |
| commit | 015abee404760249a5c968b9ce29216b94b8ced1 (patch) | |
| tree | f5dc5aacadc46fa210ef43aa54d934fef9552bd2 | |
| parent | b7d46644e554ed017dfabc0841acf418d0584bc9 (diff) | |
| download | linux-015abee404760249a5c968b9ce29216b94b8ced1.tar.gz linux-015abee404760249a5c968b9ce29216b94b8ced1.tar.bz2 linux-015abee404760249a5c968b9ce29216b94b8ced1.zip | |
PM: runtime: add tracepoint for runtime_status changes
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 <vilasbhat@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | drivers/base/power/runtime.c | 1 | ||||
| -rw-r--r-- | include/trace/events/rpm.h | 42 |
2 files changed, 43 insertions, 0 deletions
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 5275a6b2e980..2ee45841486b 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 */ |