perf evsel: Do missing feature fallbacks in just one place

Instead of doing it in stat, top, record or any other tool that opens
event descriptors.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-vr8hzph83d5t2mdlkf565h84@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 28 insertions, 3 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 7a2a3dc..ee6ee3f 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -22,6 +22,11 @@
 #include <linux/perf_event.h>
 #include "perf_regs.h"
 
+static struct {
+	bool sample_id_all;
+	bool exclude_guest;
+} perf_missing_features;
+
 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
 
 static int __perf_evsel__sample_size(u64 sample_type)
@@ -463,7 +468,7 @@ void perf_evsel__config(struct perf_evsel *evsel,
 	struct perf_event_attr *attr = &evsel->attr;
 	int track = !evsel->idx; /* only the first counter needs these */
 
-	attr->sample_id_all = opts->sample_id_all_missing ? 0 : 1;
+	attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
 	attr->inherit	    = !opts->no_inherit;
 
 	perf_evsel__set_sample_bit(evsel, IP);
@@ -513,7 +518,7 @@ void perf_evsel__config(struct perf_evsel *evsel,
 	if (opts->period)
 		perf_evsel__set_sample_bit(evsel, PERIOD);
 
-	if (!opts->sample_id_all_missing &&
+	if (!perf_missing_features.sample_id_all &&
 	    (opts->sample_time || !opts->no_inherit ||
 	     perf_target__has_cpu(&opts->target)))
 		perf_evsel__set_sample_bit(evsel, TIME);
@@ -761,6 +766,13 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 		pid = evsel->cgrp->fd;
 	}
 
+fallback_missing_features:
+	if (perf_missing_features.exclude_guest)
+		evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
+retry_sample_id:
+	if (perf_missing_features.sample_id_all)
+		evsel->attr.sample_id_all = 0;
+
 	for (cpu = 0; cpu < cpus->nr; cpu++) {
 
 		for (thread = 0; thread < threads->nr; thread++) {
@@ -777,13 +789,26 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 								     group_fd, flags);
 			if (FD(evsel, cpu, thread) < 0) {
 				err = -errno;
-				goto out_close;
+				goto try_fallback;
 			}
 		}
 	}
 
 	return 0;
 
+try_fallback:
+	if (err != -EINVAL || cpu > 0 || thread > 0)
+		goto out_close;
+
+	if (!perf_missing_features.exclude_guest &&
+	    (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
+		perf_missing_features.exclude_guest = true;
+		goto fallback_missing_features;
+	} else if (!perf_missing_features.sample_id_all) {
+		perf_missing_features.sample_id_all = true;
+		goto retry_sample_id;
+	}
+
 out_close:
 	do {
 		while (--thread >= 0) {