Re: [Question] perf tools: lex parsing issue

On 25/08/2021 01:13, Ian Rogers wrote:

Thanks for getting back to me

quoted

+ if (term->type_term == PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD) {
+       term->config = strdup("period");
+ }
+
if (!head) {
         parse_events_term__delete(term);
         YYABORT;
--

----8-----

Agreed this is hacky,

This might be a *bit* better:

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index e5eae23cfceb..e597beaaa179 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c

@@ -1058,6 +1058,13 @@ static const char 

*config_term_names[__PARSE_EVENTS__TERM_TYPE_NR] = {
  	[PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE]	= "aux-sample-size",
  };

+const char * get_config_term(int term_type)
+{
+	if (term_type >= __PARSE_EVENTS__TERM_TYPE_NR)
+		return "";
+	return config_term_names[term_type];
+}
+
  static bool config_term_shrinked;

  static bool

diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index bf6e41aa9b6a..0f658732535f 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h

@@ -90,6 +90,8 @@ enum {
  	__PARSE_EVENTS__TERM_TYPE_NR,
  };

+const char *get_config_term(int term_type);
+
  struct parse_events_array {
  	size_t nr_ranges;
  	struct {

diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index 9321bd0e2f76..8d6d3fae226d 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y

@@ -832,8 +832,9 @@ PE_TERM '=' PE_NAME
  PE_TERM '=' PE_VALUE
  {
  	struct parse_events_term *term;
+	char *config = strdup(get_config_term($1));

-	ABORT_ON(parse_events_term__num(&term, (int)$1, NULL, $3, false, &@1, 

&@3));
+	ABORT_ON(parse_events_term__num(&term, (int)$1, config, $3, false, 
&@1, &@3));
  	$$ = term;
  }

We could just expose some parse-events.c API, like above.

+               }
                 if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
                         ret += scnprintf(newval + ret, sizeof(newval) - ret,
-                                        "%s=%#x", term->config, term->val.num);
+                                        "%s=%#x", config, term->val.num);
                 else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
                         ret += scnprintf(newval + ret, sizeof(newval) - ret,
-                                        "%s=%s", term->config, term->val.str);
+                                        "%s=%s", config, term->val.str);
         }

         alias->name = strdup(name);

But how about this alternative simple one:

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index e5eae23cfceb..9e5df934d22d 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c

@@ -3084,7 +3084,7 @@ int parse_events_term__num(struct 

parse_events_term **term,
  	struct parse_events_term temp = {
  		.type_val  = PARSE_EVENTS__TERM_TYPE_NUM,
  		.type_term = type_term,
-		.config    = config,
+		.config    = config ? : strdup(config_term_names[type_term]),
  		.no_value  = no_value,
  		.err_term  = loc_term ? loc_term->first_column : 0,
  		.err_val   = loc_val  ? loc_val->first_column  : 0,
-- 

It looks like a similar fix is needed in format_alias.

And the change in parse_events_term__num(), above, seems to resolve that.

Previously we would have something like these in format_alias():

buf=i915/bcs0-busy, pmu name=i915, alias->name=bcs0-busy ->str=(null)=0x1000

And now:

buf=i915/bcs0-busy, pmu name=i915, alias->name=bcs0-busy ->str=config=0x1000


Thoughts?

Thanks,
John