perf/x86/intel/uncore: Fix uncore num_counters
authorKan Liang <kan.liang@intel.com>
Thu, 11 Aug 2016 14:30:20 +0000 (07:30 -0700)
committerIngo Molnar <mingo@kernel.org>
Fri, 12 Aug 2016 06:35:04 +0000 (08:35 +0200)
commit10e9e7bd598f9a66a11a22514c68c13c41fc821b
tree7f90d252acec7c7805b0dcbb3923961ddb22f306
parent68187872c76a96ed4db7bfb064272591f02e208b
perf/x86/intel/uncore: Fix uncore num_counters

Some uncore boxes' num_counters value for Haswell server and
Broadwell server are not correct (too large, off by one).

This issue was found by comparing the code with the document. Although
there is no bug report from users yet, accessing non-existent counters
is dangerous and the behavior is undefined: it may cause miscounting or
even crashes.

This patch makes them consistent with the uncore document.

Reported-by: Lukasz Odzioba <lukasz.odzioba@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1470925820-59847-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/events/intel/uncore_snbep.c