Re: [RFC PATCH 3/3] thermal: trace: Trace when temperature is above a trip point

[Steven Rostedt <rostedt@goodmis.org>]

On Wed, 11 Jun 2014 15:53:42 +0100
Punit Agrawal <punit.agrawal@arm.com> wrote:


> >
> > /sys/kernel/debug/thermal/thermal_zone_trip/format
> 
> I don't have this file but found the following which seems to contain
> the format.

Yeah, that was typed manually, forgot "tracing". I mount the debugfs
system at /debug for easier typing. I hate the /sys/kernel/debug path.
Too much typing.

> 
> # pwd /sys/kernel/debug/tracing/events/thermal/thermal_zone_trip
> # cat format
> name: thermal_zone_trip
> ID: 463
> format:
>         field:unsigned short common_type;       offset:0;       size:2; signed:0;
>         field:unsigned char common_flags;       offset:2;       size:1; signed:0;
>         field:unsigned char common_preempt_count;       offset:3;       size:1; signed:0;
>         field:int common_pid;   offset:4;       size:4; signed:1;
> 
>         field:__data_loc char[] thermal_zone;   offset:8;       size:4; signed:0;
>         field:int id;   offset:12;      size:4; signed:1;
>         field:int trip; offset:16;      size:4; signed:1;
>         field:enum thermal_trip_type trip_type; offset:20;      size:4; signed:0;
> 
> print fmt: "thermal_zone=%s id=%d trip=%d trip_type=%s", __get_str(thermal_zone), REC->id, REC->trip, __print_symbolic(REC->trip_type, { THERMAL_TRIP_ACTIVE, "active" }, { THERMAL_TRIP_PASSIVE, "passive" }, { THERMAL_TRIP_HOT, "hot" }, { THERMAL_TRIP_CRITICAL, "critical" })
> 

For it to work with trace-cmd (and perf) you'll need to add a plugin to
define what those enums are. This is the file that trace-cmd uses to
foramat. But it has no idea how to convert something like
THERMAL_TRIP_PASSIVE into a number.

-- Steve