[PATCH 01/10] perf tools: Add fallback for exclude_guest

[Namhyung Kim]

Commit 7b100989b4f6bce70 ("perf evlist: Remove __evlist__add_default")
changed to parse "cycles:P" event instead of creating a new cycles
event for perf record.  But it also changed the way how modifiers are
handled so it doesn't set the exclude_guest bit by default.

It seems Apple M1 PMU requires exclude_guest set and returns EOPNOTSUPP
if not.  Let's add a fallback so that it can work with default events.

Fixes: 7b100989b4f6bce70 ("perf evlist: Remove __evlist__add_default")
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: James Clark <james.clark@xxxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
 tools/perf/builtin-stat.c |  3 +--
 tools/perf/util/evsel.c   | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index cf985cdb9a6ee588..d8315dae930184ba 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -639,8 +639,7 @@ static enum counter_recovery stat_handle_error(struct evsel *counter)
 	 * (behavior changed with commit b0a873e).
 	 */
 	if (errno == EINVAL || errno == ENOSYS ||
-	    errno == ENOENT || errno == EOPNOTSUPP ||
-	    errno == ENXIO) {
+	    errno == ENOENT || errno == ENXIO) {
 		if (verbose > 0)
 			ui__warning("%s event is not supported by the kernel.\n",
 				    evsel__name(counter));
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 49cc71511c0c8ce8..d59ad76b28758906 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -3244,6 +3244,27 @@ bool evsel__fallback(struct evsel *evsel, struct target *target, int err,
 		evsel->core.attr.exclude_kernel = 1;
 		evsel->core.attr.exclude_hv     = 1;
 
+		return true;
+	} else if (err == EOPNOTSUPP && !evsel->core.attr.exclude_guest &&
+		   !evsel->exclude_GH) {
+		const char *name = evsel__name(evsel);
+		char *new_name;
+		const char *sep = ":";
+
+		/* Is there already the separator in the name. */
+		if (strchr(name, '/') ||
+		    (strchr(name, ':') && !evsel->is_libpfm_event))
+			sep = "";
+
+		if (asprintf(&new_name, "%s%sH", name, sep) < 0)
+			return false;
+
+		free(evsel->name);
+		evsel->name = new_name;
+		/* Apple M1 requires exclude_guest */
+		scnprintf(msg, msgsize, "trying to fall back to excluding guest samples");
+		evsel->core.attr.exclude_guest = 1;
+
 		return true;
 	}
 
-- 
2.46.0.469.g59c65b2a67-goog