perf list: Reorganize to use callbacks to allow honouring command line options

Rather than controlling the list output with passed flags, add
callbacks that are called when an event or metric are
encountered. State is passed to the callback so that command line
options can be respected, alternatively the callbacks can be changed.

Fix a few bugs:
 - wordwrap to columns metric descriptions and expressions;
 - remove unnecessary whitespace after PMU event names;
 - the metric filter is a glob but matched using strstr which will
   always fail, switch to using a proper globmatch,
 - the detail flag gives details for extra kernel PMU events like
   branch-instructions.

In metricgroup.c switch from struct mep being a rbtree of metricgroups
containing a list of metrics, to the tree directly containing all the
metrics. In general the alias for a name is passed to the print
routine rather than being contained in the name with OR.

Committer notes:

Check the asprint() return to address this on fedora 36:

  util/print-events.c: In function ‘print_sdt_events’:
  util/print-events.c:183:33: error: ignoring return value of ‘asprintf’ declared with attribute ‘warn_unused_result’ [-Werror=unused-result]
    183 |                                 asprintf(&evt_name, "%s@%s(%.12s)", sdt_name->s, path, bid);
        |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  cc1: all warnings being treated as errors

  $ gcc --version | head -1
  gcc (GCC) 12.2.1 20220819 (Red Hat 12.2.1-2)
  $

Fix ps.pmu_glob setting when dealing with *:* events, it was being left
with a freed pointer that then at the end of cmd_list() would be double
freed.

Check if pmu_name is NULL in default_print_event() before calling
strglobmatch(pmu_name, ...) to avoid a segfault.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Xin Gao <gaoxin@cdjrlc.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: http://lore.kernel.org/lkml/20221114210723.2749751-10-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 193 insertions, 171 deletions

diff --git a/tools/perf/util/print-events.c b/tools/perf/util/print-events.c
index d53dba033597..2646ae18d9f9 100644
--- a/tools/perf/util/print-events.c
+++ b/tools/perf/util/print-events.c
@@ -28,6 +28,7 @@
 
 #define MAX_NAME_LEN 100
 
+/** Strings corresponding to enum perf_type_id. */
 static const char * const event_type_descriptors[] = {
 	"Hardware event",
 	"Software event",
@@ -55,11 +56,9 @@ static const struct event_symbol event_symbols_tool[PERF_TOOL_MAX] = {
 /*
  * Print the events from <debugfs_mount_point>/tracing/events
  */
-void print_tracepoint_events(const char *subsys_glob,
-			     const char *event_glob, bool name_only)
+void print_tracepoint_events(const struct print_callbacks *print_cb, void *print_state)
 {
 	struct dirent **sys_namelist = NULL;
-	bool printed = false;
 	int sys_items = tracing_events__scandir_alphasort(&sys_namelist);
 
 	for (int i = 0; i < sys_items; i++) {
@@ -73,10 +72,6 @@ void print_tracepoint_events(const char *subsys_glob,
 		    !strcmp(sys_dirent->d_name, ".."))
 			continue;
 
-		if (subsys_glob != NULL &&
-		    !strglobmatch(sys_dirent->d_name, subsys_glob))
-			continue;
-
 		dir_path = get_events_file(sys_dirent->d_name);
 		if (!dir_path)
 			continue;
@@ -94,41 +89,41 @@ void print_tracepoint_events(const char *subsys_glob,
 			if (tp_event_has_id(dir_path, evt_dirent) != 0)
 				continue;
 
-			if (event_glob != NULL &&
-			    !strglobmatch(evt_dirent->d_name, event_glob))
-				continue;
-
 			snprintf(evt_path, MAXPATHLEN, "%s:%s",
 				 sys_dirent->d_name, evt_dirent->d_name);
-			if (name_only)
-				printf("%s ", evt_path);
-			else {
-				printf("  %-50s [%s]\n", evt_path,
-				       event_type_descriptors[PERF_TYPE_TRACEPOINT]);
-			}
-			printed = true;
+			print_cb->print_event(print_state,
+					/*topic=*/NULL,
+					/*pmu_name=*/NULL,
+					evt_path,
+					/*event_alias=*/NULL,
+					/*scale_unit=*/NULL,
+					/*deprecated=*/false,
+					"Tracepoint event",
+					/*desc=*/NULL,
+					/*long_desc=*/NULL,
+					/*encoding_desc=*/NULL,
+					/*metric_name=*/NULL,
+					/*metric_expr=*/NULL);
 		}
 		free(dir_path);
 		free(evt_namelist);
 	}
 	free(sys_namelist);
-	if (printed && pager_in_use())
-		printf("\n");
 }
 
-void print_sdt_events(const char *subsys_glob, const char *event_glob,
-		      bool name_only)
+void print_sdt_events(const struct print_callbacks *print_cb, void *print_state)
 {
-	struct probe_cache *pcache;
-	struct probe_cache_entry *ent;
 	struct strlist *bidlist, *sdtlist;
-	struct strlist_config cfg = {.dont_dupstr = true};
-	struct str_node *nd, *nd2;
-	char *buf, *path, *ptr = NULL;
-	bool show_detail = false;
-	int ret;
-
-	sdtlist = strlist__new(NULL, &cfg);
+	struct str_node *bid_nd, *sdt_name, *next_sdt_name;
+	const char *last_sdt_name = NULL;
+
+	/*
+	 * The implicitly sorted sdtlist will hold the tracepoint name followed
+	 * by @<buildid>. If the tracepoint name is unique (determined by
+	 * looking at the adjacent nodes) the @<buildid> is dropped otherwise
+	 * the executable path and buildid are added to the name.
+	 */
+	sdtlist = strlist__new(NULL, NULL);
 	if (!sdtlist) {
 		pr_debug("Failed to allocate new strlist for SDT\n");
 		return;
@@ -138,65 +133,78 @@ void print_sdt_events(const char *subsys_glob, const char *event_glob,
 		pr_debug("Failed to get buildids: %d\n", errno);
 		return;
 	}
-	strlist__for_each_entry(nd, bidlist) {
-		pcache = probe_cache__new(nd->s, NULL);
+	strlist__for_each_entry(bid_nd, bidlist) {
+		struct probe_cache *pcache;
+		struct probe_cache_entry *ent;
+
+		pcache = probe_cache__new(bid_nd->s, NULL);
 		if (!pcache)
 			continue;
 		list_for_each_entry(ent, &pcache->entries, node) {
-			if (!ent->sdt)
-				continue;
-			if (subsys_glob &&
-			    !strglobmatch(ent->pev.group, subsys_glob))
-				continue;
-			if (event_glob &&
-			    !strglobmatch(ent->pev.event, event_glob))
-				continue;
-			ret = asprintf(&buf, "%s:%s@%s", ent->pev.group,
-					ent->pev.event, nd->s);
-			if (ret > 0)
-				strlist__add(sdtlist, buf);
+			char buf[1024];
+
+			snprintf(buf, sizeof(buf), "%s:%s@%s",
+				 ent->pev.group, ent->pev.event, bid_nd->s);
+			strlist__add(sdtlist, buf);
 		}
 		probe_cache__delete(pcache);
 	}
 	strlist__delete(bidlist);
 
-	strlist__for_each_entry(nd, sdtlist) {
-		buf = strchr(nd->s, '@');
-		if (buf)
-			*(buf++) = '\0';
-		if (name_only) {
-			printf("%s ", nd->s);
-			continue;
-		}
-		nd2 = strlist__next(nd);
-		if (nd2) {
-			ptr = strchr(nd2->s, '@');
-			if (ptr)
-				*ptr = '\0';
-			if (strcmp(nd->s, nd2->s) == 0)
-				show_detail = true;
+	strlist__for_each_entry(sdt_name, sdtlist) {
+		bool show_detail = false;
+		char *bid = strchr(sdt_name->s, '@');
+		char *evt_name = NULL;
+
+		if (bid)
+			*(bid++) = '\0';
+
+		if (last_sdt_name && !strcmp(last_sdt_name, sdt_name->s)) {
+			show_detail = true;
+		} else {
+			next_sdt_name = strlist__next(sdt_name);
+			if (next_sdt_name) {
+				char *bid2 = strchr(next_sdt_name->s, '@');
+
+				if (bid2)
+					*bid2 = '\0';
+				if (strcmp(sdt_name->s, next_sdt_name->s) == 0)
+					show_detail = true;
+				if (bid2)
+					*bid2 = '@';
+			}
 		}
+		last_sdt_name = sdt_name->s;
+
 		if (show_detail) {
-			path = build_id_cache__origname(buf);
-			ret = asprintf(&buf, "%s@%s(%.12s)", nd->s, path, buf);
-			if (ret > 0) {
-				printf("  %-50s [%s]\n", buf, "SDT event");
-				free(buf);
+			char *path = build_id_cache__origname(bid);
+
+			if (path) {
+				if (asprintf(&evt_name, "%s@%s(%.12s)", sdt_name->s, path, bid) < 0)
+					evt_name = NULL;
+				free(path);
 			}
-			free(path);
-		} else
-			printf("  %-50s [%s]\n", nd->s, "SDT event");
-		if (nd2) {
-			if (strcmp(nd->s, nd2->s) != 0)
-				show_detail = false;
-			if (ptr)
-				*ptr = '@';
 		}
+		print_cb->print_event(print_state,
+				/*topic=*/NULL,
+				/*pmu_name=*/NULL,
+				evt_name ?: sdt_name->s,
+				/*event_alias=*/NULL,
+				/*deprecated=*/false,
+				/*scale_unit=*/NULL,
+				"SDT event",
+				/*desc=*/NULL,
+				/*long_desc=*/NULL,
+				/*encoding_desc=*/NULL,
+				/*metric_name=*/NULL,
+				/*metric_expr=*/NULL);
+
+		free(evt_name);
 	}
 	strlist__delete(sdtlist);
 }
 
-int print_hwcache_events(const char *event_glob, bool name_only)
+int print_hwcache_events(const struct print_callbacks *print_cb, void *print_state)
 {
 	struct strlist *evt_name_list = strlist__new(NULL, NULL);
 	struct str_node *nd;
@@ -216,9 +224,6 @@ int print_hwcache_events(const char *event_glob, bool name_only)
 				char name[64];
 
 				__evsel__hw_cache_type_op_res_name(type, op, i, name, sizeof(name));
-				if (event_glob != NULL && !strglobmatch(name, event_glob))
-					continue;
-
 				if (!perf_pmu__has_hybrid()) {
 					if (is_event_supported(PERF_TYPE_HW_CACHE,
 							       type | (op << 8) | (i << 16)))
@@ -240,55 +245,47 @@ int print_hwcache_events(const char *event_glob, bool name_only)
 	}
 
 	strlist__for_each_entry(nd, evt_name_list) {
-		if (name_only) {
-			printf("%s ", nd->s);
-			continue;
-		}
-		printf("  %-50s [%s]\n", nd->s, event_type_descriptors[PERF_TYPE_HW_CACHE]);
+		print_cb->print_event(print_state,
+				"cache",
+				/*pmu_name=*/NULL,
+				nd->s,
+				/*event_alias=*/NULL,
+				/*scale_unit=*/NULL,
+				/*deprecated=*/false,
+				event_type_descriptors[PERF_TYPE_HW_CACHE],
+				/*desc=*/NULL,
+				/*long_desc=*/NULL,
+				/*encoding_desc=*/NULL,
+				/*metric_name=*/NULL,
+				/*metric_expr=*/NULL);
 	}
-	if (!strlist__empty(evt_name_list) && pager_in_use())
-		printf("\n");
-
 	strlist__delete(evt_name_list);
 	return 0;
 }
 
-static void print_tool_event(const struct event_symbol *syms, const char *event_glob,
-			     bool name_only)
-{
-	if (syms->symbol == NULL)
-		return;
-
-	if (event_glob && !(strglobmatch(syms->symbol, event_glob) ||
-	      (syms->alias && strglobmatch(syms->alias, event_glob))))
-		return;
-
-	if (name_only)
-		printf("%s ", syms->symbol);
-	else {
-		char name[MAX_NAME_LEN];
-
-		if (syms->alias && strlen(syms->alias))
-			snprintf(name, MAX_NAME_LEN, "%s OR %s", syms->symbol, syms->alias);
-		else
-			strlcpy(name, syms->symbol, MAX_NAME_LEN);
-		printf("  %-50s [%s]\n", name, "Tool event");
-	}
-}
-
-void print_tool_events(const char *event_glob, bool name_only)
+void print_tool_events(const struct print_callbacks *print_cb, void *print_state)
 {
 	// Start at 1 because the first enum entry means no tool event.
-	for (int i = 1; i < PERF_TOOL_MAX; ++i)
-		print_tool_event(event_symbols_tool + i, event_glob, name_only);
-
-	if (pager_in_use())
-		printf("\n");
+	for (int i = 1; i < PERF_TOOL_MAX; ++i) {
+		print_cb->print_event(print_state,
+				"tool",
+				/*pmu_name=*/NULL,
+				event_symbols_tool[i].symbol,
+				event_symbols_tool[i].alias,
+				/*scale_unit=*/NULL,
+				/*deprecated=*/false,
+				"Tool event",
+				/*desc=*/NULL,
+				/*long_desc=*/NULL,
+				/*encoding_desc=*/NULL,
+				/*metric_name=*/NULL,
+				/*metric_expr=*/NULL);
+	}
 }
 
-void print_symbol_events(const char *event_glob, unsigned int type,
-			 struct event_symbol *syms, unsigned int max,
-			 bool name_only)
+void print_symbol_events(const struct print_callbacks *print_cb, void *print_state,
+			 unsigned int type, const struct event_symbol *syms,
+			 unsigned int max)
 {
 	struct strlist *evt_name_list = strlist__new(NULL, NULL);
 	struct str_node *nd;
@@ -305,10 +302,6 @@ void print_symbol_events(const char *event_glob, unsigned int type,
 		if (syms[i].symbol == NULL)
 			continue;
 
-		if (event_glob != NULL && !(strglobmatch(syms[i].symbol, event_glob) ||
-		      (syms[i].alias && strglobmatch(syms[i].alias, event_glob))))
-			continue;
-
 		if (!is_event_supported(type, i))
 			continue;
 
@@ -322,63 +315,92 @@ void print_symbol_events(const char *event_glob, unsigned int type,
 	}
 
 	strlist__for_each_entry(nd, evt_name_list) {
-		if (name_only) {
-			printf("%s ", nd->s);
-			continue;
+		char *alias = strstr(nd->s, " OR ");
+
+		if (alias) {
+			*alias = '\0';
+			alias += 4;
 		}
-		printf("  %-50s [%s]\n", nd->s, event_type_descriptors[type]);
+		print_cb->print_event(print_state,
+				/*topic=*/NULL,
+				/*pmu_name=*/NULL,
+				nd->s,
+				alias,
+				/*scale_unit=*/NULL,
+				/*deprecated=*/false,
+				event_type_descriptors[type],
+				/*desc=*/NULL,
+				/*long_desc=*/NULL,
+				/*encoding_desc=*/NULL,
+				/*metric_name=*/NULL,
+				/*metric_expr=*/NULL);
 	}
-	if (!strlist__empty(evt_name_list) && pager_in_use())
-		printf("\n");
-
 	strlist__delete(evt_name_list);
 }
 
 /*
  * Print the help text for the event symbols:
  */
-void print_events(const char *event_glob, bool name_only, bool quiet_flag,
-			bool long_desc, bool details_flag, bool deprecated,
-			const char *pmu_name)
+void print_events(const struct print_callbacks *print_cb, void *print_state)
 {
-	print_symbol_events(event_glob, PERF_TYPE_HARDWARE,
-			    event_symbols_hw, PERF_COUNT_HW_MAX, name_only);
-
-	print_symbol_events(event_glob, PERF_TYPE_SOFTWARE,
-			    event_symbols_sw, PERF_COUNT_SW_MAX, name_only);
-	print_tool_events(event_glob, name_only);
-
-	print_hwcache_events(event_glob, name_only);
-
-	print_pmu_events(event_glob, name_only, quiet_flag, long_desc,
-			details_flag, deprecated, pmu_name);
-
-	if (event_glob != NULL)
-		return;
-
-	if (!name_only) {
-		printf("  %-50s [%s]\n",
-		       "rNNN",
-		       event_type_descriptors[PERF_TYPE_RAW]);
-		printf("  %-50s [%s]\n",
-		       "cpu/t1=v1[,t2=v2,t3 ...]/modifier",
-		       event_type_descriptors[PERF_TYPE_RAW]);
-		if (pager_in_use())
-			printf("   (see 'man perf-list' on how to encode it)\n\n");
-
-		printf("  %-50s [%s]\n",
-		       "mem:<addr>[/len][:access]",
-			event_type_descriptors[PERF_TYPE_BREAKPOINT]);
-		if (pager_in_use())
-			printf("\n");
-	}
-
-	print_tracepoint_events(NULL, NULL, name_only);
-
-	print_sdt_events(NULL, NULL, name_only);
-
-	metricgroup__print(true, true, NULL, name_only, details_flag,
-			   pmu_name);
-
-	print_libpfm_events(name_only, long_desc);
+	print_symbol_events(print_cb, print_state, PERF_TYPE_HARDWARE,
+			event_symbols_hw, PERF_COUNT_HW_MAX);
+	print_symbol_events(print_cb, print_state, PERF_TYPE_SOFTWARE,
+			event_symbols_sw, PERF_COUNT_SW_MAX);
+
+	print_tool_events(print_cb, print_state);
+
+	print_hwcache_events(print_cb, print_state);
+
+	print_pmu_events(print_cb, print_state);
+
+	print_cb->print_event(print_state,
+			/*topic=*/NULL,
+			/*pmu_name=*/NULL,
+			"rNNN",
+			/*event_alias=*/NULL,
+			/*scale_unit=*/NULL,
+			/*deprecated=*/false,
+			event_type_descriptors[PERF_TYPE_RAW],
+			/*desc=*/NULL,
+			/*long_desc=*/NULL,
+			/*encoding_desc=*/NULL,
+			/*metric_name=*/NULL,
+			/*metric_expr=*/NULL);
+
+	print_cb->print_event(print_state,
+			/*topic=*/NULL,
+			/*pmu_name=*/NULL,
+			"cpu/t1=v1[,t2=v2,t3 ...]/modifier",
+			/*event_alias=*/NULL,
+			/*scale_unit=*/NULL,
+			/*deprecated=*/false,
+			event_type_descriptors[PERF_TYPE_RAW],
+			"(see 'man perf-list' on how to encode it)",
+			/*long_desc=*/NULL,
+			/*encoding_desc=*/NULL,
+			/*metric_name=*/NULL,
+			/*metric_expr=*/NULL);
+
+	print_cb->print_event(print_state,
+			/*topic=*/NULL,
+			/*pmu_name=*/NULL,
+			"mem:<addr>[/len][:access]",
+			/*scale_unit=*/NULL,
+			/*event_alias=*/NULL,
+			/*deprecated=*/false,
+			event_type_descriptors[PERF_TYPE_BREAKPOINT],
+			/*desc=*/NULL,
+			/*long_desc=*/NULL,
+			/*encoding_desc=*/NULL,
+			/*metric_name=*/NULL,
+			/*metric_expr=*/NULL);
+
+	print_tracepoint_events(print_cb, print_state);
+
+	print_sdt_events(print_cb, print_state);
+
+	metricgroup__print(print_cb, print_state);
+
+	print_libpfm_events(print_cb, print_state);
 }