[PATCH] perf tools: Fix parser for empty pmu terms case

[Jiri Olsa]

On Sat, May 05, 2018 at 08:43:11PM -0700, Andi Kleen wrote:
> Jiri Olsa <jolsa@xxxxxxxxxx> writes:
> 
> Please fix this quickly, PT is currently totally non functional in Linus
> mainline.

attached.. Kan, could you please test it wrt your latest changes?

thanks,
jirka


---
Adrian reported broken event parsing for Intel PT:

  $ perf record -e intel_pt//u uname
  event syntax error: 'intel_pt//u'
                               \___ parser error
  Run 'perf list' for a list of valid events

It's caused by recent change in parsing grammar
(see Fixes: for commit).

Adding special rule with empty terms config to handle
the reported case and moving the common rule code into
new parse_events_pmu function.

Fixes: 9a4a931ce847 ("perf pmu: Fix pmu events parsing rule")
Reported-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-uorb0azuem7b7ydace7cf6vc@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
 tools/perf/util/parse-events.c | 46 +++++++++++++++++++++++++++++++++++++
 tools/perf/util/parse-events.h |  3 +++
 tools/perf/util/parse-events.y | 51 +++++++++++++-----------------------------
 3 files changed, 65 insertions(+), 35 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 3576aaaa9e4c..7cf326a8effe 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -8,6 +8,7 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <sys/param.h>
+#include <fnmatch.h>
 #include "term.h"
 #include "../perf.h"
 #include "evlist.h"
@@ -1294,6 +1295,51 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 	return evsel ? 0 : -ENOMEM;
 }
 
+int parse_events_pmu(struct parse_events_state *parse_state,
+		     struct list_head *list, char *name,
+		     struct list_head *head_config)
+{
+	struct list_head *orig_terms;
+	struct perf_pmu *pmu = NULL;
+	char *pattern = NULL;
+	int ok = 0;
+
+	if (!parse_events_add_pmu(parse_state, list, name,
+				  head_config, false, false))
+		return 0;
+
+	if (parse_events_copy_term_list(head_config, &orig_terms))
+		return -1;
+
+	if (asprintf(&pattern, "%s*", name) < 0)
+		goto out;
+
+	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
+		char *tmp = pmu->name;
+
+		if (!strncmp(tmp, "uncore_", 7) &&
+		    strncmp(name, "uncore_", 7))
+			tmp += 7;
+		if (!fnmatch(pattern, tmp, 0)) {
+			struct list_head *terms;
+
+			if (parse_events_copy_term_list(orig_terms, &terms)) {
+				ok = 0;
+				goto out;
+			}
+			if (!parse_events_add_pmu(parse_state, list, pmu->name,
+						  terms, true, false))
+				ok++;
+			parse_events_terms__delete(terms);
+		}
+	}
+
+out:
+	parse_events_terms__delete(orig_terms);
+	free(pattern);
+	return ok ? 0 : -1;
+}
+
 int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
 			       char *str, struct list_head **listp)
 {
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 4473dac27aee..553fcaf5d23e 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -170,6 +170,9 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 			 struct list_head *head_config,
 			 bool auto_merge_stats,
 			 bool use_alias);
+int parse_events_pmu(struct parse_events_state *parse_state,
+		     struct list_head *list, char *name,
+		     struct list_head *head_config);
 
 int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
 			       char *str,
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index 47f6399a309a..d44599bece43 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -8,7 +8,6 @@
 
 #define YYDEBUG 1
 
-#include <fnmatch.h>
 #include <linux/compiler.h>
 #include <linux/list.h>
 #include <linux/types.h>
@@ -226,44 +225,26 @@ event_def: event_pmu |
 event_pmu:
 PE_NAME '/' event_config '/'
 {
-	struct list_head *list, *orig_terms, *terms;
+	struct list_head *list;
+
+	ALLOC_LIST(list);
 
-	if (parse_events_copy_term_list($3, &orig_terms))
+	if (parse_events_pmu(_parse_state, list, $1, $3))
 		YYABORT;
 
-	ALLOC_LIST(list);
-	if (parse_events_add_pmu(_parse_state, list, $1, $3, false, false)) {
-		struct perf_pmu *pmu = NULL;
-		int ok = 0;
-		char *pattern;
-
-		if (asprintf(&pattern, "%s*", $1) < 0)
-			YYABORT;
-
-		while ((pmu = perf_pmu__scan(pmu)) != NULL) {
-			char *name = pmu->name;
-
-			if (!strncmp(name, "uncore_", 7) &&
-			    strncmp($1, "uncore_", 7))
-				name += 7;
-			if (!fnmatch(pattern, name, 0)) {
-				if (parse_events_copy_term_list(orig_terms, &terms)) {
-					free(pattern);
-					YYABORT;
-				}
-				if (!parse_events_add_pmu(_parse_state, list, pmu->name, terms, true, false))
-					ok++;
-				parse_events_terms__delete(terms);
-			}
-		}
-
-		free(pattern);
-
-		if (!ok)
-			YYABORT;
-	}
 	parse_events_terms__delete($3);
-	parse_events_terms__delete(orig_terms);
+	$$ = list;
+}
+|
+PE_NAME '/' '/'
+{
+	struct list_head *list;
+
+	ALLOC_LIST(list);
+
+	if (parse_events_pmu(_parse_state, list, $1, NULL))
+		YYABORT;
+
 	$$ = list;
 }
 |
-- 
2.13.6