rtla/timerlat: Add action on end feature

Implement actions on end next to actions on threshold. A new option,
--on-end is added, parallel to --on-threshold. Instead of being
executed whenever a latency threshold is reached, it is executed at the
end of the measurement.

For example:

$ rtla timerlat hist -d 5s --on-end trace

will save the trace output at the end.

All actions supported by --on-threshold are also supported by --on-end,
except for continue, which does nothing with --on-end.

Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Chang Yin <cyin@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Cc: Crystal Wood <crwood@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250626123405.1496931-6-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
pull/1320/head
Tomas Glozar 2025-06-26 14:34:01 +02:00 committed by Steven Rostedt (Google)
parent 8d933d5c89
commit 3aadb65db5
3 changed files with 65 additions and 29 deletions

View File

@ -48,7 +48,10 @@ struct timerlat_params {
struct sched_attr sched_param;
struct trace_events *events;
enum timerlat_tracing_mode mode;
struct actions actions;
struct actions threshold_actions;
struct actions end_actions;
union {
struct {
/* top only */

View File

@ -758,6 +758,7 @@ static void timerlat_hist_usage(char *usage)
" --trace-buffer-size kB: set the per-cpu trace buffer size in kB",
" --deepest-idle-state n: only go down to idle state n on cpus used by timerlat to reduce exit from idle latency",
" --on-threshold <action>: define action to be executed at latency threshold, multiple are allowed",
" --on-end <action>: define action to be executed at measurement end, multiple are allowed",
NULL,
};
@ -793,7 +794,8 @@ static struct timerlat_params
if (!params)
exit(1);
actions_init(&params->actions);
actions_init(&params->threshold_actions);
actions_init(&params->end_actions);
/* disabled by default */
params->dma_latency = -1;
@ -846,6 +848,7 @@ static struct timerlat_params
{"trace-buffer-size", required_argument, 0, '\3'},
{"deepest-idle-state", required_argument, 0, '\4'},
{"on-threshold", required_argument, 0, '\5'},
{"on-end", required_argument, 0, '\6'},
{0, 0, 0, 0}
};
@ -1038,7 +1041,14 @@ static struct timerlat_params
params->deepest_idle_state = get_llong_from_str(optarg);
break;
case '\5':
retval = actions_parse(&params->actions, optarg);
retval = actions_parse(&params->threshold_actions, optarg);
if (retval) {
err_msg("Invalid action %s\n", optarg);
exit(EXIT_FAILURE);
}
break;
case '\6':
retval = actions_parse(&params->end_actions, optarg);
if (retval) {
err_msg("Invalid action %s\n", optarg);
exit(EXIT_FAILURE);
@ -1050,7 +1060,7 @@ static struct timerlat_params
}
if (trace_output)
actions_add_trace_output(&params->actions, trace_output);
actions_add_trace_output(&params->threshold_actions, trace_output);
if (geteuid()) {
err_msg("rtla needs root permission\n");
@ -1077,7 +1087,8 @@ static struct timerlat_params
* mixed mode
*/
if (params->mode == TRACING_MODE_BPF &&
(params->actions.present[ACTION_TRACE_OUTPUT] || !params->no_aa))
(params->threshold_actions.present[ACTION_TRACE_OUTPUT] ||
params->end_actions.present[ACTION_TRACE_OUTPUT] || !params->no_aa))
params->mode = TRACING_MODE_MIXED;
return params;
@ -1270,13 +1281,15 @@ int timerlat_hist_main(int argc, char *argv[])
}
}
if (params->actions.present[ACTION_TRACE_OUTPUT]) {
if (params->threshold_actions.present[ACTION_TRACE_OUTPUT] ||
params->end_actions.present[ACTION_TRACE_OUTPUT]) {
record = osnoise_init_trace_tool("timerlat");
if (!record) {
err_msg("Failed to enable the trace instance\n");
goto out_free;
}
params->actions.trace_output_inst = record->trace.inst;
params->threshold_actions.trace_output_inst = record->trace.inst;
params->end_actions.trace_output_inst = record->trace.inst;
if (params->events) {
retval = trace_events_enable(&record->trace, params->events);
@ -1342,7 +1355,7 @@ int timerlat_hist_main(int argc, char *argv[])
* tracing while enabling other instances. The trace instance is the
* one with most valuable information.
*/
if (params->actions.present[ACTION_TRACE_OUTPUT])
if (record)
trace_instance_start(&record->trace);
if (!params->no_aa)
trace_instance_start(&aa->trace);
@ -1375,14 +1388,14 @@ int timerlat_hist_main(int argc, char *argv[])
}
if (osnoise_trace_is_off(tool, record)) {
actions_perform(&params->actions);
actions_perform(&params->threshold_actions);
if (!params->actions.continue_flag)
if (!params->threshold_actions.continue_flag)
/* continue flag not set, break */
break;
/* continue action reached, re-enable tracing */
if (params->actions.present[ACTION_TRACE_OUTPUT])
if (record)
trace_instance_start(&record->trace);
if (!params->no_aa)
trace_instance_start(&aa->trace);
@ -1403,14 +1416,14 @@ int timerlat_hist_main(int argc, char *argv[])
if (!stop_tracing) {
/* Threshold overflow, perform actions on threshold */
actions_perform(&params->actions);
actions_perform(&params->threshold_actions);
if (!params->actions.continue_flag)
if (!params->threshold_actions.continue_flag)
/* continue flag not set, break */
break;
/* continue action reached, re-enable tracing */
if (params->actions.present[ACTION_TRACE_OUTPUT])
if (record)
trace_instance_start(&record->trace);
if (!params->no_aa)
trace_instance_start(&aa->trace);
@ -1435,6 +1448,8 @@ int timerlat_hist_main(int argc, char *argv[])
timerlat_print_stats(params, tool);
actions_perform(&params->end_actions);
return_value = PASSED;
if (osnoise_trace_is_off(tool, record) && !stop_tracing) {
@ -1464,7 +1479,8 @@ out_free:
osnoise_destroy_tool(aa);
osnoise_destroy_tool(record);
osnoise_destroy_tool(tool);
actions_destroy(&params->actions);
actions_destroy(&params->threshold_actions);
actions_destroy(&params->end_actions);
if (params->mode != TRACING_MODE_TRACEFS)
timerlat_bpf_destroy();
free(params);

View File

@ -517,6 +517,7 @@ static void timerlat_top_usage(char *usage)
" --trace-buffer-size kB: set the per-cpu trace buffer size in kB",
" --deepest-idle-state n: only go down to idle state n on cpus used by timerlat to reduce exit from idle latency",
" --on-threshold <action>: define action to be executed at latency threshold, multiple are allowed",
" --on-end: define action to be executed at measurement end, multiple are allowed",
NULL,
};
@ -552,7 +553,8 @@ static struct timerlat_params
if (!params)
exit(1);
actions_init(&params->actions);
actions_init(&params->threshold_actions);
actions_init(&params->end_actions);
/* disabled by default */
params->dma_latency = -1;
@ -597,6 +599,7 @@ static struct timerlat_params
{"trace-buffer-size", required_argument, 0, '7'},
{"deepest-idle-state", required_argument, 0, '8'},
{"on-threshold", required_argument, 0, '9'},
{"on-end", required_argument, 0, '\1'},
{0, 0, 0, 0}
};
@ -623,6 +626,7 @@ static struct timerlat_params
/* set trace */
trace_output = "timerlat_trace.txt";
break;
case '5':
/* it is here because it is similar to -a */
@ -776,7 +780,14 @@ static struct timerlat_params
params->deepest_idle_state = get_llong_from_str(optarg);
break;
case '9':
retval = actions_parse(&params->actions, optarg);
retval = actions_parse(&params->threshold_actions, optarg);
if (retval) {
err_msg("Invalid action %s\n", optarg);
exit(EXIT_FAILURE);
}
break;
case '\1':
retval = actions_parse(&params->end_actions, optarg);
if (retval) {
err_msg("Invalid action %s\n", optarg);
exit(EXIT_FAILURE);
@ -788,7 +799,7 @@ static struct timerlat_params
}
if (trace_output)
actions_add_trace_output(&params->actions, trace_output);
actions_add_trace_output(&params->threshold_actions, trace_output);
if (geteuid()) {
err_msg("rtla needs root permission\n");
@ -812,7 +823,8 @@ static struct timerlat_params
* mixed mode
*/
if (params->mode == TRACING_MODE_BPF &&
(params->actions.present[ACTION_TRACE_OUTPUT] || !params->no_aa))
(params->threshold_actions.present[ACTION_TRACE_OUTPUT] ||
params->end_actions.present[ACTION_TRACE_OUTPUT] || !params->no_aa))
params->mode = TRACING_MODE_MIXED;
return params;
@ -934,14 +946,14 @@ timerlat_top_main_loop(struct osnoise_tool *top,
timerlat_print_stats(params, top);
if (osnoise_trace_is_off(top, record)) {
actions_perform(&params->actions);
actions_perform(&params->threshold_actions);
if (!params->actions.continue_flag)
if (!params->threshold_actions.continue_flag)
/* continue flag not set, break */
break;
/* continue action reached, re-enable tracing */
if (params->actions.present[ACTION_TRACE_OUTPUT])
if (record)
trace_instance_start(&record->trace);
if (!params->no_aa)
trace_instance_start(&aa->trace);
@ -993,14 +1005,14 @@ timerlat_top_bpf_main_loop(struct osnoise_tool *top,
if (wait_retval == 1) {
/* Stopping requested by tracer */
actions_perform(&params->actions);
actions_perform(&params->threshold_actions);
if (!params->actions.continue_flag)
if (!params->threshold_actions.continue_flag)
/* continue flag not set, break */
break;
/* continue action reached, re-enable tracing */
if (params->actions.present[ACTION_TRACE_OUTPUT])
if (record)
trace_instance_start(&record->trace);
if (!params->no_aa)
trace_instance_start(&aa->trace);
@ -1128,13 +1140,15 @@ int timerlat_top_main(int argc, char *argv[])
}
}
if (params->actions.present[ACTION_TRACE_OUTPUT]) {
if (params->threshold_actions.present[ACTION_TRACE_OUTPUT] ||
params->end_actions.present[ACTION_TRACE_OUTPUT]) {
record = osnoise_init_trace_tool("timerlat");
if (!record) {
err_msg("Failed to enable the trace instance\n");
goto out_free;
}
params->actions.trace_output_inst = record->trace.inst;
params->threshold_actions.trace_output_inst = record->trace.inst;
params->end_actions.trace_output_inst = record->trace.inst;
if (params->events) {
retval = trace_events_enable(&record->trace, params->events);
@ -1201,7 +1215,7 @@ int timerlat_top_main(int argc, char *argv[])
* tracing while enabling other instances. The trace instance is the
* one with most valuable information.
*/
if (params->actions.present[ACTION_TRACE_OUTPUT])
if (record)
trace_instance_start(&record->trace);
if (!params->no_aa)
trace_instance_start(&aa->trace);
@ -1236,6 +1250,8 @@ int timerlat_top_main(int argc, char *argv[])
timerlat_print_stats(params, top);
actions_perform(&params->end_actions);
return_value = PASSED;
if (osnoise_trace_is_off(top, record) && !stop_tracing) {
@ -1276,7 +1292,8 @@ out_free:
osnoise_destroy_tool(aa);
osnoise_destroy_tool(record);
osnoise_destroy_tool(top);
actions_destroy(&params->actions);
actions_destroy(&params->threshold_actions);
actions_destroy(&params->end_actions);
if (params->mode != TRACING_MODE_TRACEFS)
timerlat_bpf_destroy();
free(params);