perf list: Add a --tui option to launch ilist

Add a --tui option to perf list that launches the textual based ilist
script through perf script, similar to perf timechart --tui. Rather
than printing the events, the PMUs, events and metrics can be browsed
interactively and the selected event or metric is counted on each CPU.
Arguments after '--' are passed to the script.

Assisted-by: Antigravity:gemini-3.1-pro
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Documentation/perf-list.txt

@@ -10,6 +10,7 @@ SYNOPSIS
 [verse]
 'perf list' [<options>]
             [hw|sw|cache|tracepoint|pmu|sdt|metric|metricgroup|event_glob]
+'perf list' --tui [-- <ilist options>]
 
 DESCRIPTION
 -----------
@@ -51,6 +52,15 @@ Output in JSON format.
 --output=::
 	Output file name. By default output is written to stdout.
 
+--tui::
+Rather than printing the events, interactively browse the PMUs, events and
+metrics in the terminal using the 'ilist' python script (see
+linkperf:perf-script[1]). Selecting an event or metric shows its description
+and counts it on each CPU. The script requires the perf python module and the
+python 'textual' library. Other options are ignored, arguments after '--' are
+passed to the script, for example 'perf list --tui -- -I 0.5' to update the
+counts every 0.5 seconds.
+
 [[EVENT_MODIFIERS]]
 EVENT MODIFIERS
 ---------------

tools/perf/builtin-list.c

@@ -24,8 +24,10 @@
 #include <subcmd/parse-options.h>
 #include <linux/zalloc.h>
 #include <ctype.h>
+#include <errno.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 /**
  * struct print_state - State and configuration passed to the default_print
@@ -538,6 +540,31 @@ static bool default_skip_duplicate_pmus(void *ps)
 	return !print_state->long_desc;
 }
 
+/*
+ * Launch the interactive textual based ilist python script via 'perf script'
+ * that finds the script and sets up the python environment. Arguments are
+ * passed to the script.
+ */
+static int list__tui(int argc, const char **argv)
+{
+	const char **script_argv;
+	int script_argc = 0, ret;
+
+	script_argv = calloc(argc + 4, sizeof(*script_argv));
+	if (!script_argv)
+		return -ENOMEM;
+
+	script_argv[script_argc++] = "script";
+	script_argv[script_argc++] = "ilist";
+	script_argv[script_argc++] = "--";
+	for (int i = 0; i < argc; i++)
+		script_argv[script_argc++] = argv[i];
+
+	ret = cmd_script(script_argc, script_argv);
+	free(script_argv);
+	return ret;
+}
+
 int cmd_list(int argc, const char **argv)
 {
 	int i, ret = 0;
@@ -562,6 +589,7 @@ int cmd_list(int argc, const char **argv)
 	const char *unit_name = NULL;
 	const char *output_path = NULL;
 	bool json = false;
+	bool use_tui = false;
 	struct option list_options[] = {
 		OPT_BOOLEAN(0, "raw-dump", &default_ps.name_only, "Dump raw events"),
 		OPT_BOOLEAN('j', "json", &json, "JSON encode events and metrics"),
@@ -578,6 +606,8 @@ int cmd_list(int argc, const char **argv)
 			   "Limit PMU or metric printing to the given PMU (e.g. cpu, core or atom)."),
 		OPT_STRING(0, "unit", &unit_name, "PMU name",
 			   "Limit PMU or metric printing to the specified PMU."),
+		OPT_BOOLEAN(0, "tui", &use_tui,
+			    "Interactively browse and count events and metrics with ilist"),
 		OPT_INCR(0, "debug", &verbose,
 			     "Enable debugging output"),
 		OPT_END()
@@ -588,6 +618,7 @@ int cmd_list(int argc, const char **argv)
 #else
 		"perf list [<options>] [hw|sw|cache|tracepoint|pmu|sdt|metric|metricgroup|event_glob]",
 #endif
+		"perf list --tui [-- <ilist options>]",
 		NULL
 	};
 
@@ -598,6 +629,9 @@ int cmd_list(int argc, const char **argv)
 	argc = parse_options(argc, argv, list_options, list_usage,
 			     PARSE_OPT_STOP_AT_NON_OPTION);
 
+	if (use_tui)
+		return list__tui(argc, argv);
+
 	if (json)
 		ps = &json_ps.common;