[PATCH 1/3] powerpc/perf: Infrastructure to support addition of blacklisted events

[Madhavan Srinivasan]

Introduce code to support addition of blacklisted events for a
processor version. A 'pointer' and 'int' variable to hold the
number of events are added to 'struct power_pmu', along with a
generic function to loop through the list to validate the given
event. Generic function 'is_event_blacklisted' is called in
power_pmu_event_init() to detect and reject early.

Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/perf_event_server.h |  2 ++
 arch/powerpc/perf/core-book3s.c              | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/arch/powerpc/include/asm/perf_event_server.h b/arch/powerpc/include/asm/perf_event_server.h
index 723bf48e7494..67a8a9585d50 100644
--- a/arch/powerpc/include/asm/perf_event_server.h
+++ b/arch/powerpc/include/asm/perf_event_server.h
@@ -53,6 +53,8 @@ struct power_pmu {
 			       [PERF_COUNT_HW_CACHE_OP_MAX]
 			       [PERF_COUNT_HW_CACHE_RESULT_MAX];
 
+	int		n_blacklist_ev;
+	int 		*blacklist_ev;
 	/* BHRB entries in the PMU */
 	int		bhrb_nr;
 };
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index c4525323d691..73f997b84d19 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -1819,6 +1819,18 @@ static int hw_perf_cache_event(u64 config, u64 *eventp)
 	return 0;
 }
 
+static bool is_event_blacklisted(u64 ev)
+{
+	int i;
+
+	for (i=0; i < ppmu->n_blacklist_ev; i++) {
+		if (ppmu->blacklist_ev[i] == ev)
+			return true;
+	}
+
+	return false;
+}
+
 static int power_pmu_event_init(struct perf_event *event)
 {
 	u64 ev;
@@ -1844,15 +1856,24 @@ static int power_pmu_event_init(struct perf_event *event)
 		ev = event->attr.config;
 		if (ev >= ppmu->n_generic || ppmu->generic_events[ev] == 0)
 			return -EOPNOTSUPP;
+
+		if (ppmu->blacklist_ev && is_event_blacklisted(ev))
+			return -EINVAL;
 		ev = ppmu->generic_events[ev];
 		break;
 	case PERF_TYPE_HW_CACHE:
 		err = hw_perf_cache_event(event->attr.config, &ev);
 		if (err)
 			return err;
+
+		if (ppmu->blacklist_ev && is_event_blacklisted(ev))
+			return -EINVAL;
 		break;
 	case PERF_TYPE_RAW:
 		ev = event->attr.config;
+
+		if (ppmu->blacklist_ev && is_event_blacklisted(ev))
+			return -EINVAL;
 		break;
 	default:
 		return -ENOENT;
-- 
2.7.4