perf tools: Suggest inbuilt commands for unknown command

The existing unknown command code looks for perf scripts like
perf-archive.sh and perf-iostat.sh, however, inbuilt commands aren't
suggested. Add the inbuilt commands so they may be suggested too.

Before:

  $ perf reccord
  perf: 'reccord' is not a perf-command. See 'perf --help'.
  $

After:

  $ perf reccord
  perf: 'reccord' is not a perf-command. See 'perf --help'.

  Did you mean this?
          record
  $

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240301201306.2680986-1-irogers@google.com
[ Added some fixes from Ian to problems I noticed while testing ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 17 insertions, 6 deletions

diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 921bee0a6437..bd3f80b5bb46 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -18,6 +18,7 @@
 #include <subcmd/run-command.h>
 #include "util/parse-events.h"
 #include <subcmd/parse-options.h>
+#include <subcmd/help.h>
 #include "util/debug.h"
 #include "util/event.h"
 #include "util/util.h" // usage()
@@ -458,7 +459,7 @@ static int libperf_print(enum libperf_print_level level,
 
 int main(int argc, const char **argv)
 {
-	int err;
+	int err, done_help = 0;
 	const char *cmd;
 	char sbuf[STRERR_BUFSIZE];
 
@@ -557,22 +558,32 @@ int main(int argc, const char **argv)
 	pthread__block_sigwinch();
 
 	while (1) {
-		static int done_help;
-
 		run_argv(&argc, &argv);
 
 		if (errno != ENOENT)
 			break;
 
 		if (!done_help) {
-			cmd = argv[0] = help_unknown_cmd(cmd);
+			struct cmdnames main_cmds = {};
+
+			for (unsigned int i = 0; i < ARRAY_SIZE(commands); i++) {
+				add_cmdname(&main_cmds,
+					    commands[i].cmd,
+					    strlen(commands[i].cmd));
+			}
+			cmd = argv[0] = help_unknown_cmd(cmd, &main_cmds);
+			clean_cmdnames(&main_cmds);
 			done_help = 1;
+			if (!cmd)
+				break;
 		} else
 			break;
 	}
 
-	fprintf(stderr, "Failed to run command '%s': %s\n",
-		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
+	if (cmd) {
+		fprintf(stderr, "Failed to run command '%s': %s\n",
+			cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
+	}
 out:
 	if (debug_fp)
 		fclose(debug_fp);