[PATCH V2 1/1] perf/x86/intel/uncore: fix uncore num_counters

[PATCH V2 1/1] perf/x86/intel/uncore: fix uncore num_counters

[kan.liang]

From: Kan Liang <kan.liang@intel.com>

This issue was found by comparing the code with the document. Although
there is no bug report from user yet, accessing non-existent counters
are dangerous. The behavior is undefined. It may cause miscounting or
even crash.

Some uncore boxes' num_counters for Haswell server and Broadwell server
are not correct.

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>
---

Changes since V1:
 - Refine the changelog.

 arch/x86/events/intel/uncore_snbep.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
index 824e540..8aee83b 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -2626,7 +2626,7 @@ void hswep_uncore_cpu_init(void)
 
 static struct intel_uncore_type hswep_uncore_ha = {
 	.name		= "ha",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 2,
 	.perf_ctr_bits	= 48,
 	SNBEP_UNCORE_PCI_COMMON_INIT(),
@@ -2645,7 +2645,7 @@ static struct uncore_event_desc hswep_uncore_imc_events[] = {
 
 static struct intel_uncore_type hswep_uncore_imc = {
 	.name		= "imc",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 8,
 	.perf_ctr_bits	= 48,
 	.fixed_ctr_bits	= 48,
@@ -2691,7 +2691,7 @@ static struct intel_uncore_type hswep_uncore_irp = {
 
 static struct intel_uncore_type hswep_uncore_qpi = {
 	.name			= "qpi",
-	.num_counters		= 5,
+	.num_counters		= 4,
 	.num_boxes		= 3,
 	.perf_ctr_bits		= 48,
 	.perf_ctr		= SNBEP_PCI_PMON_CTR0,
@@ -2773,7 +2773,7 @@ static struct event_constraint hswep_uncore_r3qpi_constraints[] = {
 
 static struct intel_uncore_type hswep_uncore_r3qpi = {
 	.name		= "r3qpi",
-	.num_counters   = 4,
+	.num_counters   = 3,
 	.num_boxes	= 3,
 	.perf_ctr_bits	= 44,
 	.constraints	= hswep_uncore_r3qpi_constraints,
@@ -2972,7 +2972,7 @@ static struct intel_uncore_type bdx_uncore_ha = {
 
 static struct intel_uncore_type bdx_uncore_imc = {
 	.name		= "imc",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 8,
 	.perf_ctr_bits	= 48,
 	.fixed_ctr_bits	= 48,
-- 
2.5.5

[tip:perf/urgent] perf/x86/intel/uncore: Fix uncore num_counters

[tip-bot for Kan Liang]

Commit-ID:  10e9e7bd598f9a66a11a22514c68c13c41fc821b
Gitweb:     http://git.kernel.org/tip/10e9e7bd598f9a66a11a22514c68c13c41fc821b
Author:     Kan Liang <kan.liang@intel.com>
AuthorDate: Thu, 11 Aug 2016 07:30:20 -0700
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 12 Aug 2016 08:35:04 +0200

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 | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
index 824e540..8aee83b 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -2626,7 +2626,7 @@ void hswep_uncore_cpu_init(void)
 
 static struct intel_uncore_type hswep_uncore_ha = {
 	.name		= "ha",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 2,
 	.perf_ctr_bits	= 48,
 	SNBEP_UNCORE_PCI_COMMON_INIT(),
@@ -2645,7 +2645,7 @@ static struct uncore_event_desc hswep_uncore_imc_events[] = {
 
 static struct intel_uncore_type hswep_uncore_imc = {
 	.name		= "imc",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 8,
 	.perf_ctr_bits	= 48,
 	.fixed_ctr_bits	= 48,
@@ -2691,7 +2691,7 @@ static struct intel_uncore_type hswep_uncore_irp = {
 
 static struct intel_uncore_type hswep_uncore_qpi = {
 	.name			= "qpi",
-	.num_counters		= 5,
+	.num_counters		= 4,
 	.num_boxes		= 3,
 	.perf_ctr_bits		= 48,
 	.perf_ctr		= SNBEP_PCI_PMON_CTR0,
@@ -2773,7 +2773,7 @@ static struct event_constraint hswep_uncore_r3qpi_constraints[] = {
 
 static struct intel_uncore_type hswep_uncore_r3qpi = {
 	.name		= "r3qpi",
-	.num_counters   = 4,
+	.num_counters   = 3,
 	.num_boxes	= 3,
 	.perf_ctr_bits	= 44,
 	.constraints	= hswep_uncore_r3qpi_constraints,
@@ -2972,7 +2972,7 @@ static struct intel_uncore_type bdx_uncore_ha = {
 
 static struct intel_uncore_type bdx_uncore_imc = {
 	.name		= "imc",
-	.num_counters   = 5,
+	.num_counters   = 4,
 	.num_boxes	= 8,
 	.perf_ctr_bits	= 48,
 	.fixed_ctr_bits	= 48,