perf timechart: Add an interactive --tui mode

Add ttimechart.py, a textual based interactive timechart, and a --tui
option to perf timechart that launches it through perf script. Rather
than writing an SVG file, per-CPU (busy, frequency and idle state),
per-task (running, runnable and blocked) and I/O timelines are shown in
the terminal along with a summary table. The timelines can be zoomed,
panned and the state of the selected row at the cursor is described,
including the task that woke it. The -i, -P, -T and -p options are
passed to the script.

The data is loaded in a background thread and the timelines are shown
and updated as it loads. A --dump option prints a text summary without
the UI.

Committer testing:

Fist record a short session with:

  root@x2:/home/acme/git/perf-tools-next# perf timechart record
  ^C[ perf record: Woken up 9 times to write data ]
  [ perf record: Captured and wrote 4.489 MB perf.data (29719 samples) ]
  root@x2:/home/acme/git/perf-tools-next#

Then try the TUI with:

  root@x2:/home/acme/git/perf-tools-next# tools/perf/python/ttimechart.py

or:

  root@x2:/home/acme/git/perf-tools-next# perf timechart --tui

Assisted-by: Antigravity:gemini-3.1-pro
Signed-off-by: Alice Rogers <alice.mei.rogers@gmail.com>
Co-developed-by: Ian Rogers <irogers@google.com>
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-timechart.txt

@@ -53,6 +53,14 @@ TIMECHART OPTIONS
 -f::
 --force::
 	Don't complain, do it.
+--tui::
+	Rather than writing an SVG file, interactively display the timechart
+	in the terminal using the 'ttimechart' python script (see
+	linkperf:perf-script[1]). The script requires the perf python module
+	and the python 'textual' library. The CPU, task, I/O and summary views
+	can be zoomed ('+'/'-'), panned (shift+arrows) and the state of the
+	selected row at the cursor is described. The -i, -P, -T and -p options
+	are passed to the script, other output options are ignored.
 --symfs=<directory[,layout]>::
         Look for files with symbols relative to this directory. The optional
         layout can be 'hierarchy' (default, matches full path) or 'flat'

tools/perf/builtin-timechart.c

@@ -10,6 +10,7 @@
 
 #include <errno.h>
 #include <inttypes.h>
+#include <stdlib.h>
 
 #include "builtin.h"
 #include "util/color.h"
@@ -68,6 +69,7 @@ struct timechart {
 				with_backtrace,
 				topology;
 	bool			force;
+	bool			use_tui;
 	/* IO related settings */
 	bool			io_only,
 				skip_eagain;
@@ -1756,6 +1758,41 @@ static int __cmd_timechart(struct timechart *tchart, const char *output_name)
 	return ret;
 }
 
+/*
+ * Launch the interactive textual based python script via 'perf script' that
+ * finds the script, sets up the python environment and passes the global
+ * input_name (set by -i) to the script as '-i <input_name>'.
+ */
+static int timechart__tui(struct timechart *tchart)
+{
+	struct process_filter *filt;
+	const char **script_argv;
+	int script_argc = 0, nr_args = 5, ret;
+
+	for (filt = process_filter; filt; filt = filt->next)
+		nr_args += 2;
+
+	script_argv = calloc(nr_args + 1, sizeof(*script_argv));
+	if (!script_argv)
+		return -ENOMEM;
+
+	script_argv[script_argc++] = "script";
+	script_argv[script_argc++] = "ttimechart";
+	script_argv[script_argc++] = "--";
+	if (tchart->power_only)
+		script_argv[script_argc++] = "-P";
+	if (tchart->tasks_only)
+		script_argv[script_argc++] = "-T";
+	for (filt = process_filter; filt; filt = filt->next) {
+		script_argv[script_argc++] = "-p";
+		script_argv[script_argc++] = filt->name;
+	}
+
+	ret = cmd_script(script_argc, script_argv);
+	free(script_argv);
+	return ret;
+}
+
 static int timechart__io_record(int argc, const char **argv, const char *output_data)
 {
 	unsigned int rec_argc, i;
@@ -2079,6 +2116,8 @@ int cmd_timechart(int argc, const char **argv)
 		     "merge events that are merge-dist us apart",
 		     parse_time),
 	OPT_BOOLEAN('f', "force", &tchart.force, "don't complain, do it"),
+	OPT_BOOLEAN(0, "tui", &tchart.use_tui,
+		    "interactive terminal timechart using the ttimechart python script"),
 	OPT_PARENT(timechart_common_options),
 	};
 	const char * const timechart_subcommands[] = { "record", NULL };
@@ -2146,6 +2185,11 @@ int cmd_timechart(int argc, const char **argv)
 	} else if (argc)
 		usage_with_options(timechart_usage, timechart_options);
 
+	if (tchart.use_tui) {
+		ret = timechart__tui(&tchart);
+		goto out;
+	}
+
 	setup_pager();
 
 	ret = __cmd_timechart(&tchart, output_name);