rtla: Add -e/--event support

Add -e/--event option. This option enables an event in the trace (-t)
session. The argument can be a specific event, e.g., -e sched:sched_switch,
or all events of a system group, e.g., -e sched. Multiple -e are allowed.
It is only active when -t or -a are set.

This option is available for all current tools.

Link: https://lkml.kernel.org/r/6a3b753be9b1e811953995f7f21a86918ad13390.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Documentation/tools/rtla/common_options.rst

@@ -14,6 +14,10 @@
 
         Save the stopped trace to [*file|osnoise_trace.txt*].
 
+**-e**, **--event** *sys:event*
+
+        Enable an event in the trace (**-t**) session. The argument can be a specific event, e.g., **-e** *sched:sched_switch*, or all events of a system group, e.g., **-e** *sched*. Multiple **-e** are allowed. It is only active when **-t** or **-a** are set.
+
 **-P**, **--priority** *o:prio|r:prio|f:prio|d:runtime:period*
 
         Set scheduling parameters to the osnoise tracer threads, the format to set the priority are:

tools/tracing/rtla/src/osnoise_hist.c

@@ -29,6 +29,7 @@ struct osnoise_hist_params {
 	int			set_sched;
 	int			output_divisor;
 	struct sched_attr	sched_param;
+	struct trace_events	*events;
 
 	char			no_header;
 	char			no_summary;
@@ -427,8 +428,8 @@ static void osnoise_hist_usage(char *usage)
 	static const char * const msg[] = {
 		"",
 		"  usage: rtla osnoise hist [-h] [-D] [-d s] [-a us] [-p us] [-r us] [-s us] [-S us] \\",
-		"	  [-T us] [-t[=file]] [-c cpu-list] [-P priority] [-b N] [-E N] [--no-header] \\",
-		"	  [--no-summary] [--no-index] [--with-zeros]",
+		"	  [-T us] [-t[=file]] [-e sys[:event]] [-c cpu-list] [-P priority] [-b N] [-E N] \\",
+		"	  [--no-header] [--no-summary] [--no-index] [--with-zeros]",
 		"",
 		"	  -h/--help: print this menu",
 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us sample is hit",
@@ -441,6 +442,7 @@ static void osnoise_hist_usage(char *usage)
 		"	  -d/--duration time[s|m|h|d]: duration of the session",
 		"	  -D/--debug: print debug info",
 		"	  -t/--trace[=file]: save the stopped trace to [file|osnoise_trace.txt]",
+		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	  -b/--bucket-size N: set the histogram bucket size (default 1)",
 		"	  -E/--entries N: set the number of entries of the histogram (default 256)",
 		"	     --no-header: do not print header",
@@ -474,6 +476,7 @@ static struct osnoise_hist_params
 *osnoise_hist_parse_args(int argc, char *argv[])
 {
 	struct osnoise_hist_params *params;
+	struct trace_events *tevent;
 	int retval;
 	int c;
 
@@ -501,6 +504,7 @@ static struct osnoise_hist_params
 			{"stop",		required_argument,	0, 's'},
 			{"stop-total",		required_argument,	0, 'S'},
 			{"trace",		optional_argument,	0, 't'},
+			{"event",		required_argument,	0, 'e'},
 			{"threshold",		required_argument,	0, 'T'},
 			{"no-header",		no_argument,		0, '0'},
 			{"no-summary",		no_argument,		0, '1'},
@@ -512,7 +516,7 @@ static struct osnoise_hist_params
 		/* getopt_long stores the option index here. */
 		int option_index = 0;
 
-		c = getopt_long(argc, argv, "a:c:b:d:E:Dhp:P:r:s:S:t::T:0123",
+		c = getopt_long(argc, argv, "a:c:b:d:e:E:Dhp:P:r:s:S:t::T:0123",
 				 long_options, &option_index);
 
 		/* detect the end of the options. */
@@ -550,6 +554,18 @@ static struct osnoise_hist_params
 			if (!params->duration)
 				osnoise_hist_usage("Invalid -D duration\n");
 			break;
+		case 'e':
+			tevent = trace_event_alloc(optarg);
+			if (!tevent) {
+				err_msg("Error alloc trace event");
+				exit(EXIT_FAILURE);
+			}
+
+			if (params->events)
+				tevent->next = params->events;
+
+			params->events = tevent;
+			break;
 		case 'E':
 			params->entries = get_llong_from_str(optarg);
 			if ((params->entries < 10) || (params->entries > 9999999))
@@ -778,6 +794,13 @@ int osnoise_hist_main(int argc, char *argv[])
 			err_msg("Failed to enable the trace instance\n");
 			goto out_hist;
 		}
+
+		if (params->events) {
+			retval = trace_events_enable(&record->trace, params->events);
+			if (retval)
+				goto out_hist;
+		}
+
 		trace_instance_start(&record->trace);
 	}
 
@@ -817,6 +840,8 @@ int osnoise_hist_main(int argc, char *argv[])
 	}
 
 out_hist:
+	trace_events_destroy(&record->trace, params->events);
+	params->events = NULL;
 	osnoise_free_histogram(tool->data);
 out_destroy:
 	osnoise_destroy_tool(record);

tools/tracing/rtla/src/osnoise_top.c

@@ -31,6 +31,7 @@ struct osnoise_top_params {
 	int			quiet;
 	int			set_sched;
 	struct sched_attr	sched_param;
+	struct trace_events	*events;
 };
 
 struct osnoise_top_cpu {
@@ -246,7 +247,7 @@ void osnoise_top_usage(char *usage)
 
 	static const char * const msg[] = {
 		"  usage: rtla osnoise [top] [-h] [-q] [-D] [-d s] [-a us] [-p us] [-r us] [-s us] [-S us] \\",
-		"	  [-T us] [-t[=file]] [-c cpu-list] [-P priority]",
+		"	  [-T us] [-t[=file]] [-e sys[:event]] [-c cpu-list] [-P priority]",
 		"",
 		"	  -h/--help: print this menu",
 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us sample is hit",
@@ -259,6 +260,7 @@ void osnoise_top_usage(char *usage)
 		"	  -d/--duration time[s|m|h|d]: duration of the session",
 		"	  -D/--debug: print debug info",
 		"	  -t/--trace[=file]: save the stopped trace to [file|osnoise_trace.txt]",
+		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	  -q/--quiet print only a summary at the end",
 		"	  -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
 		"		o:prio - use SCHED_OTHER with prio",
@@ -286,6 +288,7 @@ void osnoise_top_usage(char *usage)
 struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
 {
 	struct osnoise_top_params *params;
+	struct trace_events *tevent;
 	int retval;
 	int c;
 
@@ -299,6 +302,7 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
 			{"cpus",		required_argument,	0, 'c'},
 			{"debug",		no_argument,		0, 'D'},
 			{"duration",		required_argument,	0, 'd'},
+			{"event",		required_argument,	0, 'e'},
 			{"help",		no_argument,		0, 'h'},
 			{"period",		required_argument,	0, 'p'},
 			{"priority",		required_argument,	0, 'P'},
@@ -314,7 +318,7 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
 		/* getopt_long stores the option index here. */
 		int option_index = 0;
 
-		c = getopt_long(argc, argv, "a:c:d:Dhp:P:qr:s:S:t::T:",
+		c = getopt_long(argc, argv, "a:c:d:De:hp:P:qr:s:S:t::T:",
 				 long_options, &option_index);
 
 		/* Detect the end of the options. */
@@ -347,6 +351,18 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
 			if (!params->duration)
 				osnoise_top_usage("Invalid -D duration\n");
 			break;
+		case 'e':
+			tevent = trace_event_alloc(optarg);
+			if (!tevent) {
+				err_msg("Error alloc trace event");
+				exit(EXIT_FAILURE);
+			}
+
+			if (params->events)
+				tevent->next = params->events;
+			params->events = tevent;
+
+			break;
 		case 'h':
 		case '?':
 			osnoise_top_usage(NULL);
@@ -556,6 +572,13 @@ int osnoise_top_main(int argc, char **argv)
 			err_msg("Failed to enable the trace instance\n");
 			goto out_top;
 		}
+
+		if (params->events) {
+			retval = trace_events_enable(&record->trace, params->events);
+			if (retval)
+				goto out_top;
+		}
+
 		trace_instance_start(&record->trace);
 	}
 
@@ -597,6 +620,8 @@ int osnoise_top_main(int argc, char **argv)
 	}
 
 out_top:
+	trace_events_destroy(&record->trace, params->events);
+	params->events = NULL;
 	osnoise_free_top(tool->data);
 	osnoise_destroy_tool(record);
 	osnoise_destroy_tool(tool);

tools/tracing/rtla/src/timerlat_hist.c

@@ -29,6 +29,7 @@ struct timerlat_hist_params {
 	int			duration;
 	int			set_sched;
 	struct sched_attr	sched_param;
+	struct trace_events	*events;
 
 	char			no_irq;
 	char			no_thread;
@@ -429,8 +430,8 @@ static void timerlat_hist_usage(char *usage)
 	char *msg[] = {
 		"",
 		"  usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-a us] [-p us] [-i us] [-T us] [-s us] \\",
-		"         [-t[=file]] [-c cpu-list] [-P priority] [-E N] [-b N]  [--no-irq] [--no-thread] [--no-header] \\",
-		"         [--no-summary] [--no-index] [--with-zeros]",
+		"         [-t[=file]] [-e sys[:event]] [-c cpu-list] [-P priority] [-E N] [-b N] [--no-irq] \\",
+		"         [--no-thread] [--no-header] [--no-summary] [--no-index] [--with-zeros]",
 		"",
 		"	  -h/--help: print this menu",
 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
@@ -441,7 +442,8 @@ static void timerlat_hist_usage(char *usage)
 		"	  -c/--cpus cpus: run the tracer only on the given cpus",
 		"	  -d/--duration time[m|h|d]: duration of the session in seconds",
 		"	  -D/--debug: print debug info",
-		"	  -T/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]",
+		"	  -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]",
+		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	  -n/--nano: display data in nanoseconds",
 		"	  -b/--bucket-size N: set the histogram bucket size (default 1)",
 		"	  -E/--entries N: set the number of entries of the histogram (default 256)",
@@ -478,6 +480,7 @@ static struct timerlat_hist_params
 *timerlat_hist_parse_args(int argc, char *argv[])
 {
 	struct timerlat_hist_params *params;
+	struct trace_events *tevent;
 	int auto_thresh;
 	int retval;
 	int c;
@@ -507,6 +510,7 @@ static struct timerlat_hist_params
 			{"stack",		required_argument,	0, 's'},
 			{"thread",		required_argument,	0, 'T'},
 			{"trace",		optional_argument,	0, 't'},
+			{"event",		required_argument,	0, 'e'},
 			{"no-irq",		no_argument,		0, '0'},
 			{"no-thread",		no_argument,		0, '1'},
 			{"no-header",		no_argument,		0, '2'},
@@ -519,7 +523,7 @@ static struct timerlat_hist_params
 		/* getopt_long stores the option index here. */
 		int option_index = 0;
 
-		c = getopt_long(argc, argv, "a:c:b:d:E:Dhi:np:P:s:t::T:012345",
+		c = getopt_long(argc, argv, "a:c:b:d:e:E:Dhi:np:P:s:t::T:012345",
 				 long_options, &option_index);
 
 		/* detect the end of the options. */
@@ -559,6 +563,18 @@ static struct timerlat_hist_params
 			if (!params->duration)
 				timerlat_hist_usage("Invalid -D duration\n");
 			break;
+		case 'e':
+			tevent = trace_event_alloc(optarg);
+			if (!tevent) {
+				err_msg("Error alloc trace event");
+				exit(EXIT_FAILURE);
+			}
+
+			if (params->events)
+				tevent->next = params->events;
+
+			params->events = tevent;
+			break;
 		case 'E':
 			params->entries = get_llong_from_str(optarg);
 			if ((params->entries < 10) || (params->entries > 9999999))
@@ -791,6 +807,13 @@ int timerlat_hist_main(int argc, char *argv[])
 			err_msg("Failed to enable the trace instance\n");
 			goto out_hist;
 		}
+
+		if (params->events) {
+			retval = trace_events_enable(&record->trace, params->events);
+			if (retval)
+				goto out_hist;
+		}
+
 		trace_instance_start(&record->trace);
 	}
 
@@ -828,6 +851,8 @@ int timerlat_hist_main(int argc, char *argv[])
 	}
 
 out_hist:
+	trace_events_destroy(&record->trace, params->events);
+	params->events = NULL;
 	timerlat_free_histogram(tool->data);
 	osnoise_destroy_tool(record);
 	osnoise_destroy_tool(tool);

tools/tracing/rtla/src/timerlat_top.c

@@ -30,6 +30,7 @@ struct timerlat_top_params {
 	int			quiet;
 	int			set_sched;
 	struct sched_attr	sched_param;
+	struct trace_events	*events;
 };
 
 struct timerlat_top_cpu {
@@ -267,7 +268,7 @@ static void timerlat_top_usage(char *usage)
 	static const char *const msg[] = {
 		"",
 		"  usage: rtla timerlat [top] [-h] [-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\",
-		"	  [[-t[=file]] -c cpu-list] [-P priority]",
+		"	  [[-t[=file]] [-e sys[:event]] [-c cpu-list] [-P priority]",
 		"",
 		"	  -h/--help: print this menu",
 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
@@ -279,6 +280,7 @@ static void timerlat_top_usage(char *usage)
 		"	  -d/--duration time[m|h|d]: duration of the session in seconds",
 		"	  -D/--debug: print debug info",
 		"	  -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]",
+		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	  -n/--nano: display data in nanoseconds",
 		"	  -q/--quiet print only a summary at the end",
 		"	  -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
@@ -308,6 +310,7 @@ static struct timerlat_top_params
 *timerlat_top_parse_args(int argc, char **argv)
 {
 	struct timerlat_top_params *params;
+	struct trace_events *tevent;
 	long long auto_thresh;
 	int retval;
 	int c;
@@ -325,6 +328,7 @@ static struct timerlat_top_params
 			{"cpus",		required_argument,	0, 'c'},
 			{"debug",		no_argument,		0, 'D'},
 			{"duration",		required_argument,	0, 'd'},
+			{"event",		required_argument,	0, 'e'},
 			{"help",		no_argument,		0, 'h'},
 			{"irq",			required_argument,	0, 'i'},
 			{"nano",		no_argument,		0, 'n'},
@@ -340,7 +344,7 @@ static struct timerlat_top_params
 		/* getopt_long stores the option index here. */
 		int option_index = 0;
 
-		c = getopt_long(argc, argv, "a:c:d:Dhi:np:P:qs:t::T:",
+		c = getopt_long(argc, argv, "a:c:d:De:hi:np:P:qs:t::T:",
 				 long_options, &option_index);
 
 		/* detect the end of the options. */
@@ -375,6 +379,17 @@ static struct timerlat_top_params
 			if (!params->duration)
 				timerlat_top_usage("Invalid -D duration\n");
 			break;
+		case 'e':
+			tevent = trace_event_alloc(optarg);
+			if (!tevent) {
+				err_msg("Error alloc trace event");
+				exit(EXIT_FAILURE);
+			}
+
+			if (params->events)
+				tevent->next = params->events;
+			params->events = tevent;
+			break;
 		case 'h':
 		case '?':
 			timerlat_top_usage(NULL);
@@ -583,6 +598,13 @@ int timerlat_top_main(int argc, char *argv[])
 			err_msg("Failed to enable the trace instance\n");
 			goto out_top;
 		}
+
+		if (params->events) {
+			retval = trace_events_enable(&record->trace, params->events);
+			if (retval)
+				goto out_top;
+		}
+
 		trace_instance_start(&record->trace);
 	}
 
@@ -624,6 +646,8 @@ int timerlat_top_main(int argc, char *argv[])
 	}
 
 out_top:
+	trace_events_destroy(&record->trace, params->events);
+	params->events = NULL;
 	timerlat_free_top(top->data);
 	osnoise_destroy_tool(record);
 	osnoise_destroy_tool(top);