Re: [PATCH 6/6][v3] perf: Document the ABI of perf sysfs entries

From: Jiri Olsa
Date: Wed Jan 16 2013 - 06:53:45 EST


On Tue, Jan 15, 2013 at 03:57:59PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Wed, Jan 09, 2013 at 05:07:03PM -0800, Sukadev Bhattiprolu escreveu:
> > [PATCH 6/6][v3] perf: Document the ABI of perf sysfs entries
> >
> > This patchset addes two new sets of files to sysfs:
> >
> > - generic and POWER-specific perf events in /sys/devices/cpu/events/
> > - perf event config format in /sys/devices/cpu/format/event
> >
> > Document the format of these files which would become part of the ABI.
> >
> > Changelog[v3]:
> > [Greg KH] Include ABI documentation.
>
> Jiri, can I have your ack on this one too?

hm, we already already 'format' definition but in testing section
(and we are missing 'events' definition there.. my bad)

anyway, after reading Documentation/ABI/README looks like we
should go for 'testing' section with this as well.. stable
seems scary at this point ;-)

jirka

>
> Greg, all ok now?
>
> - Arnaldo
>
> > Signed-off-by: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
> > ---
> > Documentation/ABI/stable/sysfs-devices-cpu-events | 54 +++++++++++++++++++++
> > Documentation/ABI/stable/sysfs-devices-cpu-format | 27 ++++++++++
> > 2 files changed, 81 insertions(+), 0 deletions(-)
> > create mode 100644 Documentation/ABI/stable/sysfs-devices-cpu-format
> >
> > diff --git a/Documentation/ABI/stable/sysfs-devices-cpu-events b/Documentation/ABI/stable/sysfs-devices-cpu-events
> > index e69de29..f37d542 100644
> > --- a/Documentation/ABI/stable/sysfs-devices-cpu-events
> > +++ b/Documentation/ABI/stable/sysfs-devices-cpu-events
> > @@ -0,0 +1,54 @@
> > +What: /sys/devices/cpu/events/
> > + /sys/devices/cpu/events/branch-misses
> > + /sys/devices/cpu/events/cache-references
> > + /sys/devices/cpu/events/cache-misses
> > + /sys/devices/cpu/events/stalled-cycles-frontend
> > + /sys/devices/cpu/events/branch-instructions
> > + /sys/devices/cpu/events/stalled-cycles-backend
> > + /sys/devices/cpu/events/instructions
> > + /sys/devices/cpu/events/cpu-cycles
> > +
> > +Date: 2013/01/08
> > +
> > +Contact: Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx>
> > +
> > +Description: Generic performance monitoring events
> > +
> > + A collection of performance monitoring events that may be
> > + supported by many/most CPUs. These events can be monitored
> > + using the 'perf(1)' tool.
> > +
> > + The contents of each file would look like:
> > +
> > + event=0xNNNN
> > +
> > + where 'N' is a hex digit.
> > +
> > +
> > +What: /sys/devices/cpu/events/PM_LD_MISS_L1
> > + /sys/devices/cpu/events/PM_LD_REF_L1
> > + /sys/devices/cpu/events/PM_CYC
> > + /sys/devices/cpu/events/PM_BRU_FIN
> > + /sys/devices/cpu/events/PM_GCT_NOSLOT_CYC
> > + /sys/devices/cpu/events/PM_BRU_MPRED
> > + /sys/devices/cpu/events/PM_INST_CMPL
> > + /sys/devices/cpu/events/PM_CMPLU_STALL
> > +
> > +Date: 2013/01/08
> > +
> > +Contact: Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx>
> > + Linux Powerpc mailing list <linuxppc-dev@xxxxxxxxxx>
> > +
> > +Description: POWER specific performance monitoring events
> > +
> > + A collection of performance monitoring events that may be
> > + supported by the POWER CPU. These events can be monitored
> > + using the 'perf(1)' tool.
> > +
> > + These events may not be supported by other CPUs.
> > +
> > + The contents of each file would look like:
> > +
> > + event=0xNNNN
> > +
> > + where 'N' is a hex digit.
> > diff --git a/Documentation/ABI/stable/sysfs-devices-cpu-format b/Documentation/ABI/stable/sysfs-devices-cpu-format
> > new file mode 100644
> > index 0000000..b15cfb2
> > --- /dev/null
> > +++ b/Documentation/ABI/stable/sysfs-devices-cpu-format
> > @@ -0,0 +1,27 @@
> > +What: /sys/devices/cpu/format/
> > + /sys/devices/cpu/format/event
> > +
> > +Date: 2013/01/08
> > +
> > +Contact: Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx>
> > +
> > +Description: Format of performance monitoring events
> > +
> > + Each CPU/architecture may use different format to represent
> > + the perf event. The 'event' file describes the configuration
> > + format of the performance monitoring event on the CPU/system.
> > +
> > + The contents of each file would look like:
> > +
> > + config:m-n
> > +
> > + where m and n are the starting and ending bits that are
> > + used to represent the event.
> > +
> > + For example, on POWER,
> > +
> > + $ cat /sys/devices/cpu/format/event
> > + config:0-20
> > +
> > + meaning that POWER uses the first 20-bits to represent a perf
> > + event.
> > --
> > 1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/