Re: [PATCH 1/2] perf tools: fix a typo of a Power7 event name
From: Sukadev Bhattiprolu
Date: Wed Jun 19 2013 - 22:29:59 EST
Michael Ellerman [michael@xxxxxxxxxxxxxx] wrote:
| On Wed, 2013-06-19 at 17:15 +0800, Runzhen Wang wrote:
| > In the Power7 PMU guide:
| > https://www.power.org/documentation/commonly-used-metrics-for-performance-analysis/
| > PM_BRU_MPRED is referred to as PM_BR_MPRED.
| > This patch fix the typo by changing the name of the event in kernel and
| > documentation accordingly.
| > Signed-off-by: Runzhen Wang <runzhen@xxxxxxxxxxxxxxxxxx>
| > ---
| > .../testing/sysfs-bus-event_source-devices-events | 2 +-
| > arch/powerpc/perf/power7-pmu.c | 12 ++++++------
| > 2 files changed, 7 insertions(+), 7 deletions(-)
| > diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
| > index 8b25ffb..3c1cc24 100644
| > --- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
| > +++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
| > @@ -29,7 +29,7 @@ Description: Generic performance monitoring events
| > What: /sys/devices/cpu/events/PM_1PLUS_PPC_CMPL
| > /sys/devices/cpu/events/PM_BRU_FIN
| > - /sys/devices/cpu/events/PM_BRU_MPRED
| > + /sys/devices/cpu/events/PM_BR_MPRED
| So you're changing the ABI.
| I think that's probably OK, but you at least need to mention _why_ you
| think it's OK.
Some of the reasons I think its ok to change:
- It is relatively new interface, specific to the Power7 platform.
- No tools that we know of actually use this interface at this point (none
are listed near the interface).
- Users of this interface (eg oprofile users migrating to perf) would be
more used to the "PM_BR_MPRED" rather than "PM_BRU_MPRED".
- These are in the ABI/testing at this point rather than ABI/stable, so
hoping we have some wiggle room.
But of course this is not a "grave error" or "security hole" which are
the justifications listed in the Documentation/ABI/README. If these
are not good enough reasons, we can leave the misnomer around and
create another file in sysfs with the correct name PM_BR_MPRED.
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/