perf/x86/intel/uncore: Add support for ARB uncore PMU on Sandy/IvyBridge

Add a new "ARB" uncore PMU that is used to monitor the uncore queue
arbiter. This is useful to measure uncore queue occupancy and similar
statistics. The registers all have the same format as the
existing CBOX PMU.

Also move the event constraints from the CBOX to ARB. The 0x80+
events are ARB events and cannot be scheduled on a CBOX PMU.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: eranian@google.com
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1434347862-28490-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/perf_event_intel_uncore_snb.c

@@ -45,6 +45,11 @@
 #define SNB_UNC_CBO_0_PER_CTR0                  0x706
 #define SNB_UNC_CBO_MSR_OFFSET                  0x10
 
+/* SNB ARB register */
+#define SNB_UNC_ARB_PER_CTR0			0x3b0
+#define SNB_UNC_ARB_PERFEVTSEL0			0x3b2
+#define SNB_UNC_ARB_MSR_OFFSET			0x10
+
 /* NHM global control register */
 #define NHM_UNC_PERF_GLOBAL_CTL                 0x391
 #define NHM_UNC_FIXED_CTR                       0x394
@@ -115,7 +120,7 @@ static struct intel_uncore_ops snb_uncore_msr_ops = {
 	.read_counter	= uncore_msr_read_counter,
 };
 
-static struct event_constraint snb_uncore_cbox_constraints[] = {
+static struct event_constraint snb_uncore_arb_constraints[] = {
 	UNCORE_EVENT_CONSTRAINT(0x80, 0x1),
 	UNCORE_EVENT_CONSTRAINT(0x83, 0x1),
 	EVENT_CONSTRAINT_END
@@ -134,14 +139,28 @@ static struct intel_uncore_type snb_uncore_cbox = {
 	.single_fixed	= 1,
 	.event_mask	= SNB_UNC_RAW_EVENT_MASK,
 	.msr_offset	= SNB_UNC_CBO_MSR_OFFSET,
-	.constraints	= snb_uncore_cbox_constraints,
 	.ops		= &snb_uncore_msr_ops,
 	.format_group	= &snb_uncore_format_group,
 	.event_descs	= snb_uncore_events,
 };
 
+static struct intel_uncore_type snb_uncore_arb = {
+	.name		= "arb",
+	.num_counters   = 2,
+	.num_boxes	= 1,
+	.perf_ctr_bits	= 44,
+	.perf_ctr	= SNB_UNC_ARB_PER_CTR0,
+	.event_ctl	= SNB_UNC_ARB_PERFEVTSEL0,
+	.event_mask	= SNB_UNC_RAW_EVENT_MASK,
+	.msr_offset	= SNB_UNC_ARB_MSR_OFFSET,
+	.constraints	= snb_uncore_arb_constraints,
+	.ops		= &snb_uncore_msr_ops,
+	.format_group	= &snb_uncore_format_group,
+};
+
 static struct intel_uncore_type *snb_msr_uncores[] = {
 	&snb_uncore_cbox,
+	&snb_uncore_arb,
 	NULL,
 };