perf/x86: Enable cycles:pp for Intel Atom

This patch updates the PEBS support for Intel Atom to provide
an alias for the cycles:pp event used by perf record/top by default
nowadays.

On Atom, only INST_RETIRED:ANY supports PEBS, so we use this event
instead with a large cmask to count cycles. Given that Core2 has
the same issue, we use the intel_pebs_aliases_core2() function for Atom
as well.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1449172990-30183-3-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/perf_event_intel.c

@@ -3370,6 +3370,7 @@ __init int intel_pmu_init(void)
 
 		x86_pmu.event_constraints = intel_gen_event_constraints;
 		x86_pmu.pebs_constraints = intel_atom_pebs_event_constraints;
+		x86_pmu.pebs_aliases = intel_pebs_aliases_core2;
 		pr_cont("Atom events, ");
 		break;
 

arch/x86/kernel/cpu/perf_event_intel_ds.c

@@ -620,6 +620,8 @@ struct event_constraint intel_atom_pebs_event_constraints[] = {
 	INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0x1),    /* MEM_LOAD_RETIRED.* */
 	/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x01),
+	/* Allow all events as PEBS with no flags */
+	INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
 	EVENT_CONSTRAINT_END
 };