perf/x86/intel: Add LBR filter support for Silvermont and Airmont CPUs

LBR filtering is also supported on the Silvermont and Airmont
microarchitectures. The layout of MSR_LBR_SELECT is the same as Nehalem.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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>
Link: http://lkml.kernel.org/r/1460706825-46163-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/events/intel/core.c

@@ -3581,7 +3581,7 @@ __init int intel_pmu_init(void)
 		memcpy(hw_cache_extra_regs, slm_hw_cache_extra_regs,
 		       sizeof(hw_cache_extra_regs));
 
-		intel_pmu_lbr_init_atom();
+		intel_pmu_lbr_init_slm();
 
 		x86_pmu.event_constraints = intel_slm_event_constraints;
 		x86_pmu.pebs_constraints = intel_slm_pebs_event_constraints;

arch/x86/events/intel/lbr.c

@@ -1058,6 +1058,24 @@ void __init intel_pmu_lbr_init_atom(void)
 	pr_cont("8-deep LBR, ");
 }
 
+/* slm */
+void __init intel_pmu_lbr_init_slm(void)
+{
+	x86_pmu.lbr_nr	   = 8;
+	x86_pmu.lbr_tos    = MSR_LBR_TOS;
+	x86_pmu.lbr_from   = MSR_LBR_CORE_FROM;
+	x86_pmu.lbr_to     = MSR_LBR_CORE_TO;
+
+	x86_pmu.lbr_sel_mask = LBR_SEL_MASK;
+	x86_pmu.lbr_sel_map  = nhm_lbr_sel_map;
+
+	/*
+	 * SW branch filter usage:
+	 * - compensate for lack of HW filter
+	 */
+	pr_cont("8-deep LBR, ");
+}
+
 /* Knights Landing */
 void intel_pmu_lbr_init_knl(void)
 {

arch/x86/events/perf_event.h

@@ -909,6 +909,8 @@ void intel_pmu_lbr_init_nhm(void);
 
 void intel_pmu_lbr_init_atom(void);
 
+void intel_pmu_lbr_init_slm(void);
+
 void intel_pmu_lbr_init_snb(void);
 
 void intel_pmu_lbr_init_hsw(void);