rtla/osnoise: Use pretty formatting only on interactive tty

osnoise top performs background/font color formatting that could make
the text output confusing if not on a terminal. Use the changes from
commit f5c0cdad ("rtla/timerlat: Use pretty formatting only on
interactive tty") as an inspiration to fix this problem.

Apply the formatting only if running on a tty, and not in quiet mode.

Link: https://lkml.kernel.org/r/Zmb-yP_3EDHliI8Z@uudg.orgSuggested-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Reviewed-by: John Kacur <jkacur@redhat.com>
Reviewed-by: Clark Williams <williams@redhat.com>
Signed-off-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>

tools/tracing/rtla/src/osnoise_top.c

@@ -42,6 +42,7 @@ struct osnoise_top_params {
 	int			hk_cpus;
 	int			warmup;
 	int			buffer_size;
+	int			pretty_output;
 	cpu_set_t		hk_cpu_set;
 	struct sched_attr	sched_param;
 	struct trace_events	*events;
@@ -163,7 +164,9 @@ static void osnoise_top_header(struct osnoise_tool *top)
 
 	get_duration(top->start_time, duration, sizeof(duration));
 
-	trace_seq_printf(s, "\033[2;37;40m");
+	if (params->pretty_output)
+		trace_seq_printf(s, "\033[2;37;40m");
+
 	trace_seq_printf(s, "                                          ");
 
 	if (params->mode == MODE_OSNOISE) {
@@ -174,12 +177,16 @@ static void osnoise_top_header(struct osnoise_tool *top)
 	}
 
 	trace_seq_printf(s, "                                   ");
-	trace_seq_printf(s, "\033[0;0;0m");
+
+	if (params->pretty_output)
+		trace_seq_printf(s, "\033[0;0;0m");
 	trace_seq_printf(s, "\n");
 
 	trace_seq_printf(s, "duration: %9s | time is in us\n", duration);
 
-	trace_seq_printf(s, "\033[2;30;47m");
+	if (params->pretty_output)
+		trace_seq_printf(s, "\033[2;30;47m");
+
 	trace_seq_printf(s, "CPU Period       Runtime ");
 	trace_seq_printf(s, "       Noise ");
 	trace_seq_printf(s, " %% CPU Aval ");
@@ -192,7 +199,8 @@ static void osnoise_top_header(struct osnoise_tool *top)
 	trace_seq_printf(s, "          IRQ      Softirq       Thread");
 
 eol:
-	trace_seq_printf(s, "\033[0;0;0m");
+	if (params->pretty_output)
+		trace_seq_printf(s, "\033[0;0;0m");
 	trace_seq_printf(s, "\n");
 }
 
@@ -619,6 +627,9 @@ osnoise_top_apply_config(struct osnoise_tool *tool, struct osnoise_top_params *p
 		auto_house_keeping(&params->monitored_cpus);
 	}
 
+	if (isatty(1) && !params->quiet)
+		params->pretty_output = 1;
+
 	return 0;
 
 out_err: