[PATCH v2 3/3] perf debug: Increase libtraceevent logging when verbose

[Ian Rogers <irogers@google.com>]

libtraceevent has added more levels of debug printout and with changes
like:
https://lore.kernel.org/linux-trace-devel/20210507095022.1079364-3-tz.stoyanov@gmail.com
previously generated output like "registering plugin" is no longer
displayed. This change makes it so that if perf's verbose debug output
is enabled then the debug and info libtraceevent messages can be
displayed.

This change was previously posted:
https://lore.kernel.org/linux-perf-users/20210923001024.550263-4-irogers@google.com/
and reverted:
https://lore.kernel.org/linux-perf-users/20220109153446.160593-1-acme@kernel.org/
The previous failure was due to -Itools/lib being on the include path
and libtraceevent in tools/lib being version 1.1.0. This meant that
when LIBTRACEEVENT_VERSION was 1.3.0 the #if succeeded, but the header
file for libtraceevent (taken from tools/lib rather than the intended
/usr/include) was for version 1.1.0 and function definitions were
missing.

Since the previous issue the -Itools/lib include path has been
removed:
https://lore.kernel.org/lkml/20221109184914.1357295-1-irogers@google.com/
As well as libtraceevent 1.1.0 has been removed from tools/lib:
https://lore.kernel.org/lkml/20221130062935.2219247-1-irogers@google.com/

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/debug.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tools/perf/util/debug.c b/tools/perf/util/debug.c
index 190e818a0717..88378c4c5dd9 100644
--- a/tools/perf/util/debug.c
+++ b/tools/perf/util/debug.c
@@ -19,12 +19,19 @@
 #include "debug.h"
 #include "print_binary.h"
 #include "target.h"
+#include "trace-event.h"
 #include "ui/helpline.h"
 #include "ui/ui.h"
 #include "util/parse-sublevel-options.h"
 
 #include <linux/ctype.h>
 
+#ifdef HAVE_LIBTRACEEVENT
+#include <traceevent/event-parse.h>
+#else
+#define LIBTRACEEVENT_VERSION 0
+#endif
+
 int verbose;
 int debug_peo_args;
 bool dump_trace = false, quiet = false;
@@ -228,6 +235,14 @@ int perf_debug_option(const char *str)
 	/* Allow only verbose value in range (0, 10), otherwise set 0. */
 	verbose = (verbose < 0) || (verbose > 10) ? 0 : verbose;
 
+#if LIBTRACEEVENT_VERSION >= MAKE_LIBTRACEEVENT_VERSION(1, 3, 0)
+	if (verbose == 1)
+		tep_set_loglevel(TEP_LOG_INFO);
+	else if (verbose == 2)
+		tep_set_loglevel(TEP_LOG_DEBUG);
+	else if (verbose >= 3)
+		tep_set_loglevel(TEP_LOG_ALL);
+#endif
 	return 0;
 }
 
-- 
2.39.0.314.g84b9a713c41-goog