perf parse-events: Make common term list to strbuf helper

A term list is turned into a string for debug output and for the str
value in the alias.

Add a helper to do this based on existing code, but then fix for
situations like events being identified.

Use strbuf to manage the dynamic memory allocation and remove the 256
byte limit.

Use in various places the string of the term list is required.

Before:

  $ sudo perf stat -vv -e inst_retired.any true
  Using CPUID GenuineIntel-6-8D-1
  intel_pt default config: tsc,mtc,mtc_period=3,psb_period=3,pt,branch
  Attempting to add event pmu 'cpu' with 'inst_retired.any,' that may result in non-fatal errors
  After aliases, add event pmu 'cpu' with 'event,period,' that may result in non-fatal errors
  inst_retired.any -> cpu/inst_retired.any/
  ...

After:

$ sudo perf stat -vv -e inst_retired.any true

  Using CPUID GenuineIntel-6-8D-1
  intel_pt default config: tsc,mtc,mtc_period=3,psb_period=3,pt,branch
  Attempt to add: cpu/inst_retired.any/
  ..after resolving event: cpu/event=0xc0,period=0x1e8483/
  inst_retired.any -> cpu/event=0xc0,period=0x1e8483/
  ...

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20230830070753.1821629-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 75 insertions, 26 deletions

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 4c812fbe0cf9..0b941b58bdc0 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -13,7 +13,7 @@
 #include <subcmd/parse-options.h>
 #include "parse-events.h"
 #include "string2.h"
-#include "strlist.h"
+#include "strbuf.h"
 #include "debug.h"
 #include <api/fs/tracing_path.h>
 #include <perf/cpumap.h>
@@ -1303,19 +1303,6 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 
 	pmu = parse_state->fake_pmu ?: perf_pmus__find(name);
 
-	if (verbose > 1 && !(pmu && pmu->selectable)) {
-		fprintf(stderr, "Attempting to add event pmu '%s' with '",
-			name);
-		if (head_config) {
-			struct parse_events_term *term;
-
-			list_for_each_entry(term, head_config, list) {
-				fprintf(stderr, "%s,", term->config);
-			}
-		}
-		fprintf(stderr, "' that may result in non-fatal errors\n");
-	}
-
 	if (!pmu) {
 		char *err_str;
 
@@ -1325,6 +1312,21 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 			parse_events_error__handle(err, loc->first_column, err_str, NULL);
 		return -EINVAL;
 	}
+
+	if (verbose > 1) {
+		struct strbuf sb;
+
+		strbuf_init(&sb, /*hint=*/ 0);
+		if (pmu->selectable && !head_config) {
+			strbuf_addf(&sb, "%s//", name);
+		} else {
+			strbuf_addf(&sb, "%s/", name);
+			parse_events_term__to_strbuf(head_config, &sb);
+			strbuf_addch(&sb, '/');
+		}
+		fprintf(stderr, "Attempt to add: %s\n", sb.buf);
+		strbuf_release(&sb);
+	}
 	if (head_config)
 		fix_raw(head_config, pmu);
 
@@ -1349,16 +1351,12 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 		return -EINVAL;
 
 	if (verbose > 1) {
-		fprintf(stderr, "After aliases, add event pmu '%s' with '",
-			name);
-		if (head_config) {
-			struct parse_events_term *term;
+		struct strbuf sb;
 
-			list_for_each_entry(term, head_config, list) {
-				fprintf(stderr, "%s,", term->config);
-			}
-		}
-		fprintf(stderr, "' that may result in non-fatal errors\n");
+		strbuf_init(&sb, /*hint=*/ 0);
+		parse_events_term__to_strbuf(head_config, &sb);
+		fprintf(stderr, "..after resolving event: %s/%s/\n", name, sb.buf);
+		strbuf_release(&sb);
 	}
 
 	/*
@@ -1460,7 +1458,12 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
 		parse_events_copy_term_list(head, &orig_head);
 		if (!parse_events_add_pmu(parse_state, list, pmu->name,
 					  orig_head, auto_merge_stats, loc)) {
-			pr_debug("%s -> %s/%s/\n", str, pmu->name, str);
+			struct strbuf sb;
+
+			strbuf_init(&sb, /*hint=*/ 0);
+			parse_events_term__to_strbuf(orig_head, &sb);
+			pr_debug("%s -> %s/%s/\n", str, pmu->name, sb.buf);
+			strbuf_release(&sb);
 			ok++;
 		}
 		parse_events_terms__delete(orig_head);
@@ -1469,7 +1472,12 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
 	if (parse_state->fake_pmu) {
 		if (!parse_events_add_pmu(parse_state, list, str, head,
 					  /*auto_merge_stats=*/true, loc)) {
-			pr_debug("%s -> %s/%s/\n", str, "fake_pmu", str);
+			struct strbuf sb;
+
+			strbuf_init(&sb, /*hint=*/ 0);
+			parse_events_term__to_strbuf(head, &sb);
+			pr_debug("%s -> %s/%s/\n", str, "fake_pmu", sb.buf);
+			strbuf_release(&sb);
 			ok++;
 		}
 	}
@@ -2085,7 +2093,7 @@ void parse_events_error__handle(struct parse_events_error *err, int idx,
 		break;
 	default:
 		pr_debug("Multiple errors dropping message: %s (%s)\n",
-			err->str, err->help);
+			err->str, err->help ?: "<no help>");
 		free(err->str);
 		err->str = str;
 		free(err->help);
@@ -2502,6 +2510,47 @@ void parse_events_terms__delete(struct list_head *terms)
 	free(terms);
 }
 
+int parse_events_term__to_strbuf(struct list_head *term_list, struct strbuf *sb)
+{
+	struct parse_events_term *term;
+	bool first = true;
+
+	if (!term_list)
+		return 0;
+
+	list_for_each_entry(term, term_list, list) {
+		int ret;
+
+		if (!first) {
+			ret = strbuf_addch(sb, ',');
+			if (ret < 0)
+				return ret;
+		}
+		first = false;
+
+		if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
+			if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER && term->val.num == 1)
+				ret = strbuf_addf(sb, "%s", term->config);
+			else
+				ret = strbuf_addf(sb, "%s=%#"PRIx64, term->config, term->val.num);
+		else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
+			if (term->config) {
+				ret = strbuf_addf(sb, "%s=", term->config);
+				if (ret < 0)
+					return ret;
+			} else if (term->type_term < __PARSE_EVENTS__TERM_TYPE_NR) {
+				ret = strbuf_addf(sb, "%s=", config_term_names[term->type_term]);
+				if (ret < 0)
+					return ret;
+			}
+			ret = strbuf_addf(sb, "%s", term->val.str);
+		}
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
 void parse_events_evlist_error(struct parse_events_state *parse_state,
 			       int idx, const char *str)
 {