perf kvm: Add min and max stats to display

Add max and min times for exit events.

v2: address Xiao's comment to use get_event function for pulling max and
    min from stats struct similar to mean and count

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1375753297-69645-4-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-kvm.c

@@ -337,14 +337,19 @@ static void clear_events_cache_stats(struct list_head *kvm_events_cache)
 	struct list_head *head;
 	struct kvm_event *event;
 	unsigned int i;
+	int j;
 
 	for (i = 0; i < EVENTS_CACHE_SIZE; i++) {
 		head = &kvm_events_cache[i];
 		list_for_each_entry(event, head, hash_entry) {
 			/* reset stats for event */
-			memset(&event->total, 0, sizeof(event->total));
-			memset(event->vcpu, 0,
-			       event->max_vcpu * sizeof(*event->vcpu));
+			event->total.time = 0;
+			init_stats(&event->total.stats);
+
+			for (j = 0; j < event->max_vcpu; ++j) {
+				event->vcpu[j].time = 0;
+				init_stats(&event->vcpu[j].stats);
+			}
 		}
 	}
 }
@@ -583,6 +588,8 @@ static int compare_kvm_event_ ## func(struct kvm_event *one,		\
 GET_EVENT_KEY(time, time);
 COMPARE_EVENT_KEY(count, stats.n);
 COMPARE_EVENT_KEY(mean, stats.mean);
+GET_EVENT_KEY(max, stats.max);
+GET_EVENT_KEY(min, stats.min);
 
 #define DEF_SORT_NAME_KEY(name, compare_key)				\
 	{ #name, compare_kvm_event_ ## compare_key }
@@ -727,20 +734,26 @@ static void print_result(struct perf_kvm_stat *kvm)
 	pr_info("%9s ", "Samples%");
 
 	pr_info("%9s ", "Time%");
+	pr_info("%10s ", "Min Time");
+	pr_info("%10s ", "Max Time");
 	pr_info("%16s ", "Avg time");
 	pr_info("\n\n");
 
 	while ((event = pop_from_result(&kvm->result))) {
-		u64 ecount, etime;
+		u64 ecount, etime, max, min;
 
 		ecount = get_event_count(event, vcpu);
 		etime = get_event_time(event, vcpu);
+		max = get_event_max(event, vcpu);
+		min = get_event_min(event, vcpu);
 
 		kvm->events_ops->decode_key(kvm, &event->key, decode);
 		pr_info("%20s ", decode);
 		pr_info("%10llu ", (unsigned long long)ecount);
 		pr_info("%8.2f%% ", (double)ecount / kvm->total_count * 100);
 		pr_info("%8.2f%% ", (double)etime / kvm->total_time * 100);
+		pr_info("%8" PRIu64 "us ", min / 1000);
+		pr_info("%8" PRIu64 "us ", max / 1000);
 		pr_info("%9.2fus ( +-%7.2f%% )", (double)etime / ecount/1e3,
 			kvm_event_rel_stddev(vcpu, event));
 		pr_info("\n");