diff --git a/Documentation/tools/rtla/common_options.rst b/Documentation/tools/rtla/common_options.rst index 721790a..af76df6 100644 --- a/Documentation/tools/rtla/common_options.rst +++ b/Documentation/tools/rtla/common_options.rst @@ -14,6 +14,25 @@ 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. + +**--filter** ** + + Filter the previous **-e** *sys:event* event with **. For further information about event filtering see https://www.kernel.org/doc/html/latest/trace/events.html#event-filtering. + +**--trigger** ** + Enable a trace event trigger to the previous **-e** *sys:event*. + If the *hist:* trigger is activated, the output histogram will be automatically saved to a file named *system_event_hist.txt*. + For example, the command: + + rtla -t -e osnoise:irq_noise --trigger="hist:key=desc,duration/1000:sort=desc,duration/1000:vals=hitcount" + + Will automatically save the content of the histogram associated to *osnoise:irq_noise* event in *osnoise_irq_noise_hist.txt*. + + For further information about event trigger see https://www.kernel.org/doc/html/latest/trace/events.html#event-triggers. + **-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: diff --git a/Documentation/tools/rtla/common_osnoise_options.rst b/Documentation/tools/rtla/common_osnoise_options.rst index d556883..f792ca5 100644 --- a/Documentation/tools/rtla/common_osnoise_options.rst +++ b/Documentation/tools/rtla/common_osnoise_options.rst @@ -1,3 +1,8 @@ +**-a**, **--auto** *us* + + Set the automatic trace mode. This mode sets some commonly used options + while debugging the system. It is equivalent to use **-s** *us* **-T 1 -t**. + **-p**, **--period** *us* Set the *osnoise* tracer period in microseconds. @@ -15,3 +20,8 @@ Stop the trace if the total sample is higher than the argument in microseconds. If **-T** is set, it will also save the trace to the output. + +**-T**, **--threshold** *us* + + Specify the minimum delta between two time reads to be considered noise. + The default threshold is *5 us*. diff --git a/Documentation/tools/rtla/common_timerlat_options.rst b/Documentation/tools/rtla/common_timerlat_options.rst index e9c1bfd..bacdea6 100644 --- a/Documentation/tools/rtla/common_timerlat_options.rst +++ b/Documentation/tools/rtla/common_timerlat_options.rst @@ -1,3 +1,10 @@ +**-a**, **--auto** *us* + + Set the automatic trace mode. This mode sets some commonly used options + while debugging the system. It is equivalent to use **-T** *us* **-s** *us* + **-t**. By default, *timerlat* tracer uses FIFO:95 for *timerlat* threads, + thus equilavent to **-P** *f:95*. + **-p**, **--period** *us* Set the *timerlat* tracer period in microseconds. @@ -14,3 +21,8 @@ Save the stack trace at the *IRQ* if a *Thread* latency is higher than the argument in us. + +**--dma-latency** *us* + Set the /dev/cpu_dma_latency to *us*, aiming to bound exit from idle latencies. + *cyclictest* sets this value to *0* by default, use **--dma-latency** *0* to have + similar results. diff --git a/tools/tracing/rtla/src/osnoise.c b/tools/tracing/rtla/src/osnoise.c index e60f186..b8ec6c1 100644 --- a/tools/tracing/rtla/src/osnoise.c +++ b/tools/tracing/rtla/src/osnoise.c @@ -656,6 +656,85 @@ void osnoise_put_print_stack(struct osnoise_context *context) } /* + * osnoise_get_tracing_thresh - read and save the original "tracing_thresh" + */ +static long long +osnoise_get_tracing_thresh(struct osnoise_context *context) +{ + long long tracing_thresh; + + if (context->tracing_thresh != OSNOISE_OPTION_INIT_VAL) + return context->tracing_thresh; + + if (context->orig_tracing_thresh != OSNOISE_OPTION_INIT_VAL) + return context->orig_tracing_thresh; + + tracing_thresh = osnoise_read_ll_config("tracing_thresh"); + if (tracing_thresh < 0) + goto out_err; + + context->orig_tracing_thresh = tracing_thresh; + return tracing_thresh; + +out_err: + return OSNOISE_OPTION_INIT_VAL; +} + +/* + * osnoise_set_tracing_thresh - set "tracing_thresh" + */ +int osnoise_set_tracing_thresh(struct osnoise_context *context, long long tracing_thresh) +{ + long long curr_tracing_thresh = osnoise_get_tracing_thresh(context); + int retval; + + if (curr_tracing_thresh == OSNOISE_OPTION_INIT_VAL) + return -1; + + retval = osnoise_write_ll_config("tracing_thresh", tracing_thresh); + if (retval < 0) + return -1; + + context->tracing_thresh = tracing_thresh; + + return 0; +} + +/* + * osnoise_restore_tracing_thresh - restore the original "tracing_thresh" + */ +void osnoise_restore_tracing_thresh(struct osnoise_context *context) +{ + int retval; + + if (context->orig_tracing_thresh == OSNOISE_OPTION_INIT_VAL) + return; + + if (context->orig_tracing_thresh == context->tracing_thresh) + goto out_done; + + retval = osnoise_write_ll_config("tracing_thresh", context->orig_tracing_thresh); + if (retval < 0) + err_msg("Could not restore original tracing_thresh\n"); + +out_done: + context->tracing_thresh = OSNOISE_OPTION_INIT_VAL; +} + +/* + * osnoise_put_tracing_thresh - restore original values and cleanup data + */ +void osnoise_put_tracing_thresh(struct osnoise_context *context) +{ + osnoise_restore_tracing_thresh(context); + + if (context->orig_tracing_thresh == OSNOISE_OPTION_INIT_VAL) + return; + + context->orig_tracing_thresh = OSNOISE_OPTION_INIT_VAL; +} + +/* * enable_osnoise - enable osnoise tracer in the trace_instance */ int enable_osnoise(struct trace_instance *trace) @@ -716,6 +795,9 @@ struct osnoise_context *osnoise_context_alloc(void) context->orig_print_stack = OSNOISE_OPTION_INIT_VAL; context->print_stack = OSNOISE_OPTION_INIT_VAL; + context->orig_tracing_thresh = OSNOISE_OPTION_INIT_VAL; + context->tracing_thresh = OSNOISE_OPTION_INIT_VAL; + osnoise_get_context(context); return context; @@ -741,6 +823,7 @@ void osnoise_put_context(struct osnoise_context *context) osnoise_put_stop_total_us(context); osnoise_put_timerlat_period_us(context); osnoise_put_print_stack(context); + osnoise_put_tracing_thresh(context); free(context); } diff --git a/tools/tracing/rtla/src/osnoise.h b/tools/tracing/rtla/src/osnoise.h index 9e4b2e2..04a4384 100644 --- a/tools/tracing/rtla/src/osnoise.h +++ b/tools/tracing/rtla/src/osnoise.h @@ -23,6 +23,10 @@ struct osnoise_context { long long orig_timerlat_period_us; long long timerlat_period_us; + /* 0 as init value */ + long long orig_tracing_thresh; + long long tracing_thresh; + /* -1 as init value because 0 is disabled */ long long orig_stop_us; long long stop_us; @@ -67,6 +71,10 @@ int osnoise_set_timerlat_period_us(struct osnoise_context *context, long long timerlat_period_us); void osnoise_restore_timerlat_period_us(struct osnoise_context *context); +int osnoise_set_tracing_thresh(struct osnoise_context *context, + long long tracing_thresh); +void osnoise_restore_tracing_thresh(struct osnoise_context *context); + void osnoise_restore_print_stack(struct osnoise_context *context); int osnoise_set_print_stack(struct osnoise_context *context, long long print_stack); diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c index 52c053c..b4380d4 100644 --- a/tools/tracing/rtla/src/osnoise_hist.c +++ b/tools/tracing/rtla/src/osnoise_hist.c @@ -21,6 +21,7 @@ struct osnoise_hist_params { char *trace_output; unsigned long long runtime; unsigned long long period; + long long threshold; long long stop_us; long long stop_total_us; int sleep_time; @@ -28,6 +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; @@ -425,19 +427,25 @@ static void osnoise_hist_usage(char *usage) static const char * const msg[] = { "", - " usage: rtla osnoise hist [-h] [-D] [-d s] [-p us] [-r us] [-s us] [-S us] [-t[=file]] \\", - " [-c cpu-list] [-P priority] [-b N] [-E N] [--no-header] [--no-summary] \\", - " [--no-index] [--with-zeros]", + " usage: rtla osnoise hist [-h] [-D] [-d s] [-a us] [-p us] [-r us] [-s us] [-S us] \\", + " [-T us] [-t[=file]] [-e sys[:event]] [--filter ] [--trigger ] \\", + " [-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", " -p/--period us: osnoise period in us", " -r/--runtime us: osnoise runtime in us", " -s/--stop us: stop trace if a single sample is higher than the argument in us", " -S/--stop-total us: stop trace if the total sample is higher than the argument in us", + " -T/--threshold us: the minimum delta to be considered a noise", " -c/--cpus cpu-list: list of cpus to run osnoise threads", " -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 : enable the in the trace instance, multiple -e are allowed", + " --filter : enable a trace event filter to the previous -e event", + " --trigger : enable a trace event trigger to the previous -e event", " -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", @@ -471,6 +479,7 @@ 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; @@ -485,6 +494,7 @@ static struct osnoise_hist_params while (1) { static struct option long_options[] = { + {"auto", required_argument, 0, 'a'}, {"bucket-size", required_argument, 0, 'b'}, {"entries", required_argument, 0, 'E'}, {"cpus", required_argument, 0, 'c'}, @@ -497,17 +507,21 @@ 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'}, {"no-index", no_argument, 0, '2'}, {"with-zeros", no_argument, 0, '3'}, + {"trigger", required_argument, 0, '4'}, + {"filter", required_argument, 0, '5'}, {0, 0, 0, 0} }; /* getopt_long stores the option index here. */ int option_index = 0; - c = getopt_long(argc, argv, "c:b:d:E:Dhp:P:r:s:S:t::0123", + c = getopt_long(argc, argv, "a:c:b:d:e:E:Dhp:P:r:s:S:t::T:01234:5:", long_options, &option_index); /* detect the end of the options. */ @@ -515,6 +529,17 @@ static struct osnoise_hist_params break; switch (c) { + case 'a': + /* set sample stop to auto_thresh */ + params->stop_us = get_llong_from_str(optarg); + + /* set sample threshold to 1 */ + params->threshold = 1; + + /* set trace */ + params->trace_output = "osnoise_trace.txt"; + + break; case 'b': params->bucket_size = get_llong_from_str(optarg); if ((params->bucket_size == 0) || (params->bucket_size >= 1000000)) @@ -534,6 +559,18 @@ 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)) @@ -565,6 +602,9 @@ static struct osnoise_hist_params case 'S': params->stop_total_us = get_llong_from_str(optarg); break; + case 'T': + params->threshold = get_llong_from_str(optarg); + break; case 't': if (optarg) /* skip = */ @@ -584,6 +624,28 @@ static struct osnoise_hist_params case '3': /* with zeros */ params->with_zeros = 1; break; + case '4': /* trigger */ + if (params->events) { + retval = trace_event_add_trigger(params->events, optarg); + if (retval) { + err_msg("Error adding trigger %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + osnoise_hist_usage("--trigger requires a previous -e\n"); + } + break; + case '5': /* filter */ + if (params->events) { + retval = trace_event_add_filter(params->events, optarg); + if (retval) { + err_msg("Error adding filter %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + osnoise_hist_usage("--filter requires a previous -e\n"); + } + break; default: osnoise_hist_usage("Invalid option"); } @@ -645,6 +707,14 @@ osnoise_hist_apply_config(struct osnoise_tool *tool, struct osnoise_hist_params } } + if (params->threshold) { + retval = osnoise_set_tracing_thresh(tool->context, params->threshold); + if (retval) { + err_msg("Failed to set tracing_thresh\n"); + goto out_err; + } + } + return 0; out_err: @@ -751,6 +821,13 @@ 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); } @@ -771,9 +848,9 @@ int osnoise_hist_main(int argc, char *argv[]) goto out_hist; } - if (!tracefs_trace_is_on(trace->inst)) + if (trace_is_off(&tool->trace, &record->trace)) break; - }; + } osnoise_read_trace_hist(tool); @@ -781,8 +858,8 @@ int osnoise_hist_main(int argc, char *argv[]) return_value = 0; - if (!tracefs_trace_is_on(trace->inst)) { - printf("rtla timelat hit stop tracing\n"); + if (trace_is_off(&tool->trace, &record->trace)) { + printf("rtla osnoise hit stop tracing\n"); if (params->trace_output) { printf(" Saving trace to %s\n", params->trace_output); save_trace_to_file(record->trace.inst, params->trace_output); @@ -790,6 +867,8 @@ 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); diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c index 7af769b..72c2fd6 100644 --- a/tools/tracing/rtla/src/osnoise_top.c +++ b/tools/tracing/rtla/src/osnoise_top.c @@ -23,6 +23,7 @@ struct osnoise_top_params { char *trace_output; unsigned long long runtime; unsigned long long period; + long long threshold; long long stop_us; long long stop_total_us; int sleep_time; @@ -30,6 +31,7 @@ struct osnoise_top_params { int quiet; int set_sched; struct sched_attr sched_param; + struct trace_events *events; }; struct osnoise_top_cpu { @@ -244,18 +246,24 @@ void osnoise_top_usage(char *usage) int i; static const char * const msg[] = { - " usage: rtla osnoise [top] [-h] [-q] [-D] [-d s] [-p us] [-r us] [-s us] [-S us] [-t[=file]] \\", + " usage: rtla osnoise [top] [-h] [-q] [-D] [-d s] [-a us] [-p us] [-r us] [-s us] [-S us] \\", + " [-T us] [-t[=file]] [-e sys[:event]] [--filter ] [--trigger ] \\", " [-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", " -p/--period us: osnoise period in us", " -r/--runtime us: osnoise runtime in us", " -s/--stop us: stop trace if a single sample is higher than the argument in us", " -S/--stop-total us: stop trace if the total sample is higher than the argument in us", + " -T/--threshold us: the minimum delta to be considered a noise", " -c/--cpus cpu-list: list of cpus to run osnoise threads", " -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 : enable the in the trace instance, multiple -e are allowed", + " --filter : enable a trace event filter to the previous -e event", + " --trigger : enable a trace event trigger to the previous -e event", " -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", @@ -283,6 +291,7 @@ 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; @@ -292,9 +301,11 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv) while (1) { static struct option long_options[] = { + {"auto", required_argument, 0, 'a'}, {"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'}, @@ -302,14 +313,17 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv) {"runtime", required_argument, 0, 'r'}, {"stop", required_argument, 0, 's'}, {"stop-total", required_argument, 0, 'S'}, + {"threshold", required_argument, 0, 'T'}, {"trace", optional_argument, 0, 't'}, + {"trigger", required_argument, 0, '0'}, + {"filter", required_argument, 0, '1'}, {0, 0, 0, 0} }; /* getopt_long stores the option index here. */ int option_index = 0; - c = getopt_long(argc, argv, "c:d:Dhp:P:qr:s:S:t::", + c = getopt_long(argc, argv, "a:c:d:De:hp:P:qr:s:S:t::T:0:1:", long_options, &option_index); /* Detect the end of the options. */ @@ -317,6 +331,17 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv) break; switch (c) { + case 'a': + /* set sample stop to auto_thresh */ + params->stop_us = get_llong_from_str(optarg); + + /* set sample threshold to 1 */ + params->threshold = 1; + + /* set trace */ + params->trace_output = "osnoise_trace.txt"; + + break; case 'c': retval = parse_cpu_list(optarg, ¶ms->monitored_cpus); if (retval) @@ -331,6 +356,18 @@ 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); @@ -367,6 +404,31 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv) else params->trace_output = "osnoise_trace.txt"; break; + case 'T': + params->threshold = get_llong_from_str(optarg); + break; + case '0': /* trigger */ + if (params->events) { + retval = trace_event_add_trigger(params->events, optarg); + if (retval) { + err_msg("Error adding trigger %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + osnoise_top_usage("--trigger requires a previous -e\n"); + } + break; + case '1': /* filter */ + if (params->events) { + retval = trace_event_add_filter(params->events, optarg); + if (retval) { + err_msg("Error adding filter %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + osnoise_top_usage("--filter requires a previous -e\n"); + } + break; default: osnoise_top_usage("Invalid option"); } @@ -425,6 +487,14 @@ osnoise_top_apply_config(struct osnoise_tool *tool, struct osnoise_top_params *p } } + if (params->threshold) { + retval = osnoise_set_tracing_thresh(tool->context, params->threshold); + if (retval) { + err_msg("Failed to set tracing_thresh\n"); + goto out_err; + } + } + return 0; out_err: @@ -529,13 +599,20 @@ 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); } tool->start_time = time(NULL); osnoise_top_set_signals(params); - do { + while (!stop_tracing) { sleep(params->sleep_time); retval = tracefs_iterate_raw_events(trace->tep, @@ -552,16 +629,16 @@ int osnoise_top_main(int argc, char **argv) if (!params->quiet) osnoise_print_stats(params, tool); - if (!tracefs_trace_is_on(trace->inst)) + if (trace_is_off(&tool->trace, &record->trace)) break; - } while (!stop_tracing); + } osnoise_print_stats(params, tool); return_value = 0; - if (!tracefs_trace_is_on(trace->inst)) { + if (trace_is_off(&tool->trace, &record->trace)) { printf("osnoise hit stop tracing\n"); if (params->trace_output) { printf(" Saving trace to %s\n", params->trace_output); @@ -570,6 +647,8 @@ 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); diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c index 237e173..dc90812 100644 --- a/tools/tracing/rtla/src/timerlat_hist.c +++ b/tools/tracing/rtla/src/timerlat_hist.c @@ -28,7 +28,9 @@ struct timerlat_hist_params { int output_divisor; int duration; int set_sched; + int dma_latency; struct sched_attr sched_param; + struct trace_events *events; char no_irq; char no_thread; @@ -428,11 +430,13 @@ static void timerlat_hist_usage(char *usage) char *msg[] = { "", - " usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-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]", + " usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-a us] [-p us] [-i us] [-T us] [-s us] \\", + " [-t[=file]] [-e sys[:event]] [--filter ] [--trigger ] [-c cpu-list] \\", + " [-P priority] [-E N] [-b N] [--no-irq] [--no-thread] [--no-header] [--no-summary] \\", + " [--no-index] [--with-zeros] [--dma-latency us]", "", " -h/--help: print this menu", + " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit", " -p/--period us: timerlat period in us", " -i/--irq us: stop trace if the irq latency is higher than the argument in us", " -T/--thread us: stop trace if the thread latency is higher than the argument in us", @@ -440,7 +444,10 @@ 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 : enable the in the trace instance, multiple -e are allowed", + " --filter : enable a trace event filter to the previous -e event", + " --trigger : enable a trace event trigger to the previous -e event", " -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)", @@ -450,6 +457,7 @@ static void timerlat_hist_usage(char *usage) " --no-summary: do not print summary", " --no-index: do not print index", " --with-zeros: print zero only entries", + " --dma-latency us: set /dev/cpu_dma_latency latency to reduce exit from idle latency", " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters", " o:prio - use SCHED_OTHER with prio", " r:prio - use SCHED_RR with prio", @@ -477,6 +485,8 @@ 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; @@ -484,6 +494,9 @@ static struct timerlat_hist_params if (!params) exit(1); + /* disabled by default */ + params->dma_latency = -1; + /* display data in microseconds */ params->output_divisor = 1000; params->bucket_size = 1; @@ -491,6 +504,7 @@ static struct timerlat_hist_params while (1) { static struct option long_options[] = { + {"auto", required_argument, 0, 'a'}, {"cpus", required_argument, 0, 'c'}, {"bucket-size", required_argument, 0, 'b'}, {"debug", no_argument, 0, 'D'}, @@ -504,19 +518,23 @@ 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'}, {"no-summary", no_argument, 0, '3'}, {"no-index", no_argument, 0, '4'}, {"with-zeros", no_argument, 0, '5'}, + {"trigger", required_argument, 0, '6'}, + {"filter", required_argument, 0, '7'}, + {"dma-latency", required_argument, 0, '8'}, {0, 0, 0, 0} }; /* getopt_long stores the option index here. */ int option_index = 0; - c = getopt_long(argc, argv, "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:0123456:7:8:", long_options, &option_index); /* detect the end of the options. */ @@ -524,6 +542,19 @@ static struct timerlat_hist_params break; switch (c) { + case 'a': + auto_thresh = get_llong_from_str(optarg); + + /* set thread stop to auto_thresh */ + params->stop_total_us = auto_thresh; + + /* get stack trace */ + params->print_stack = auto_thresh; + + /* set trace */ + params->trace_output = "timerlat_trace.txt"; + + break; case 'c': retval = parse_cpu_list(optarg, ¶ms->monitored_cpus); if (retval) @@ -543,6 +574,18 @@ 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)) @@ -600,6 +643,35 @@ static struct timerlat_hist_params case '5': /* with zeros */ params->with_zeros = 1; break; + case '6': /* trigger */ + if (params->events) { + retval = trace_event_add_trigger(params->events, optarg); + if (retval) { + err_msg("Error adding trigger %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + timerlat_hist_usage("--trigger requires a previous -e\n"); + } + break; + case '7': /* filter */ + if (params->events) { + retval = trace_event_add_filter(params->events, optarg); + if (retval) { + err_msg("Error adding filter %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + timerlat_hist_usage("--filter requires a previous -e\n"); + } + break; + case '8': + params->dma_latency = get_llong_from_str(optarg); + if (params->dma_latency < 0 || params->dma_latency > 10000) { + err_msg("--dma-latency needs to be >= 0 and < 10000"); + exit(EXIT_FAILURE); + } + break; default: timerlat_hist_usage("Invalid option"); } @@ -732,6 +804,7 @@ int timerlat_hist_main(int argc, char *argv[]) struct osnoise_tool *record = NULL; struct osnoise_tool *tool = NULL; struct trace_instance *trace; + int dma_latency_fd = -1; int return_value = 1; int retval; @@ -767,6 +840,14 @@ int timerlat_hist_main(int argc, char *argv[]) } } + if (params->dma_latency >= 0) { + dma_latency_fd = set_cpu_dma_latency(params->dma_latency); + if (dma_latency_fd < 0) { + err_msg("Could not set /dev/cpu_dma_latency.\n"); + goto out_hist; + } + } + trace_instance_start(trace); if (params->trace_output) { @@ -775,6 +856,13 @@ 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); } @@ -795,15 +883,15 @@ int timerlat_hist_main(int argc, char *argv[]) goto out_hist; } - if (!tracefs_trace_is_on(trace->inst)) + if (trace_is_off(&tool->trace, &record->trace)) break; - }; + } timerlat_print_stats(params, tool); return_value = 0; - if (!tracefs_trace_is_on(trace->inst)) { + if (trace_is_off(&tool->trace, &record->trace)) { printf("rtla timelat hit stop tracing\n"); if (params->trace_output) { printf(" Saving trace to %s\n", params->trace_output); @@ -812,6 +900,10 @@ int timerlat_hist_main(int argc, char *argv[]) } out_hist: + if (dma_latency_fd >= 0) + close(dma_latency_fd); + trace_events_destroy(&record->trace, params->events); + params->events = NULL; timerlat_free_histogram(tool->data); osnoise_destroy_tool(record); osnoise_destroy_tool(tool); diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c index d4187f6..1f754c3 100644 --- a/tools/tracing/rtla/src/timerlat_top.c +++ b/tools/tracing/rtla/src/timerlat_top.c @@ -29,7 +29,9 @@ struct timerlat_top_params { int duration; int quiet; int set_sched; + int dma_latency; struct sched_attr sched_param; + struct trace_events *events; }; struct timerlat_top_cpu { @@ -266,10 +268,12 @@ static void timerlat_top_usage(char *usage) static const char *const msg[] = { "", - " usage: rtla timerlat [top] [-h] [-q] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] [-t[=file]] \\", - " [-c cpu-list] [-P priority]", + " usage: rtla timerlat [top] [-h] [-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\", + " [[-t[=file]] [-e sys[:event]] [--filter ] [--trigger ] [-c cpu-list] \\", + " [-P priority] [--dma-latency us]", "", " -h/--help: print this menu", + " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit", " -p/--period us: timerlat period in us", " -i/--irq us: stop trace if the irq latency is higher than the argument in us", " -T/--thread us: stop trace if the thread latency is higher than the argument in us", @@ -278,8 +282,12 @@ 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 : enable the in the trace instance, multiple -e are allowed", + " --filter : enable a trace event filter to the previous -e event", + " --trigger : enable a trace event trigger to the previous -e event", " -n/--nano: display data in nanoseconds", " -q/--quiet print only a summary at the end", + " --dma-latency us: set /dev/cpu_dma_latency latency to reduce exit from idle latency", " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters", " o:prio - use SCHED_OTHER with prio", " r:prio - use SCHED_RR with prio", @@ -307,6 +315,8 @@ 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; @@ -314,14 +324,19 @@ static struct timerlat_top_params if (!params) exit(1); + /* disabled by default */ + params->dma_latency = -1; + /* display data in microseconds */ params->output_divisor = 1000; while (1) { static struct option long_options[] = { + {"auto", required_argument, 0, 'a'}, {"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'}, @@ -331,13 +346,16 @@ static struct timerlat_top_params {"stack", required_argument, 0, 's'}, {"thread", required_argument, 0, 'T'}, {"trace", optional_argument, 0, 't'}, + {"trigger", required_argument, 0, '0'}, + {"filter", required_argument, 0, '1'}, + {"dma-latency", required_argument, 0, '2'}, {0, 0, 0, 0} }; /* getopt_long stores the option index here. */ int option_index = 0; - c = getopt_long(argc, argv, "c:d:Dhi:np:P:qs:t::T:", + c = getopt_long(argc, argv, "a:c:d:De:hi:np:P:qs:t::T:0:1:2:", long_options, &option_index); /* detect the end of the options. */ @@ -345,6 +363,19 @@ static struct timerlat_top_params break; switch (c) { + case 'a': + auto_thresh = get_llong_from_str(optarg); + + /* set thread stop to auto_thresh */ + params->stop_total_us = auto_thresh; + + /* get stack trace */ + params->print_stack = auto_thresh; + + /* set trace */ + params->trace_output = "timerlat_trace.txt"; + + break; case 'c': retval = parse_cpu_list(optarg, ¶ms->monitored_cpus); if (retval) @@ -359,6 +390,17 @@ 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); @@ -396,6 +438,35 @@ static struct timerlat_top_params else params->trace_output = "timerlat_trace.txt"; break; + case '0': /* trigger */ + if (params->events) { + retval = trace_event_add_trigger(params->events, optarg); + if (retval) { + err_msg("Error adding trigger %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + timerlat_top_usage("--trigger requires a previous -e\n"); + } + break; + case '1': /* filter */ + if (params->events) { + retval = trace_event_add_filter(params->events, optarg); + if (retval) { + err_msg("Error adding filter %s\n", optarg); + exit(EXIT_FAILURE); + } + } else { + timerlat_top_usage("--filter requires a previous -e\n"); + } + break; + case '2': /* dma-latency */ + params->dma_latency = get_llong_from_str(optarg); + if (params->dma_latency < 0 || params->dma_latency > 10000) { + err_msg("--dma-latency needs to be >= 0 and < 10000"); + exit(EXIT_FAILURE); + } + break; default: timerlat_top_usage("Invalid option"); } @@ -524,6 +595,7 @@ int timerlat_top_main(int argc, char *argv[]) struct osnoise_tool *record = NULL; struct osnoise_tool *top = NULL; struct trace_instance *trace; + int dma_latency_fd = -1; int return_value = 1; int retval; @@ -559,6 +631,14 @@ int timerlat_top_main(int argc, char *argv[]) } } + if (params->dma_latency >= 0) { + dma_latency_fd = set_cpu_dma_latency(params->dma_latency); + if (dma_latency_fd < 0) { + err_msg("Could not set /dev/cpu_dma_latency.\n"); + goto out_top; + } + } + trace_instance_start(trace); if (params->trace_output) { @@ -567,6 +647,13 @@ 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); } @@ -590,16 +677,16 @@ int timerlat_top_main(int argc, char *argv[]) if (!params->quiet) timerlat_print_stats(params, top); - if (!tracefs_trace_is_on(trace->inst)) + if (trace_is_off(&top->trace, &record->trace)) break; - }; + } timerlat_print_stats(params, top); return_value = 0; - if (!tracefs_trace_is_on(trace->inst)) { + if (trace_is_off(&top->trace, &record->trace)) { printf("rtla timelat hit stop tracing\n"); if (params->trace_output) { printf(" Saving trace to %s\n", params->trace_output); @@ -608,6 +695,10 @@ int timerlat_top_main(int argc, char *argv[]) } out_top: + if (dma_latency_fd >= 0) + close(dma_latency_fd); + trace_events_destroy(&record->trace, params->events); + params->events = NULL; timerlat_free_top(top->data); osnoise_destroy_tool(record); osnoise_destroy_tool(top); diff --git a/tools/tracing/rtla/src/trace.c b/tools/tracing/rtla/src/trace.c index 83de259..5784c9f 100644 --- a/tools/tracing/rtla/src/trace.c +++ b/tools/tracing/rtla/src/trace.c @@ -190,3 +190,348 @@ int trace_instance_start(struct trace_instance *trace) { return tracefs_trace_on(trace->inst); } + +/* + * trace_events_free - free a list of trace events + */ +static void trace_events_free(struct trace_events *events) +{ + struct trace_events *tevent = events; + struct trace_events *free_event; + + while (tevent) { + free_event = tevent; + + tevent = tevent->next; + + if (free_event->filter) + free(free_event->filter); + if (free_event->trigger) + free(free_event->trigger); + free(free_event->system); + free(free_event); + } +} + +/* + * trace_event_alloc - alloc and parse a single trace event + */ +struct trace_events *trace_event_alloc(const char *event_string) +{ + struct trace_events *tevent; + + tevent = calloc(1, sizeof(*tevent)); + if (!tevent) + return NULL; + + tevent->system = strdup(event_string); + if (!tevent->system) { + free(tevent); + return NULL; + } + + tevent->event = strstr(tevent->system, ":"); + if (tevent->event) { + *tevent->event = '\0'; + tevent->event = &tevent->event[1]; + } + + return tevent; +} + +/* + * trace_event_add_filter - record an event filter + */ +int trace_event_add_filter(struct trace_events *event, char *filter) +{ + if (event->filter) + free(event->filter); + + event->filter = strdup(filter); + if (!event->filter) + return 1; + + return 0; +} + +/* + * trace_event_add_trigger - record an event trigger action + */ +int trace_event_add_trigger(struct trace_events *event, char *trigger) +{ + if (event->trigger) + free(event->trigger); + + event->trigger = strdup(trigger); + if (!event->trigger) + return 1; + + return 0; +} + +/* + * trace_event_disable_filter - disable an event filter + */ +static void trace_event_disable_filter(struct trace_instance *instance, + struct trace_events *tevent) +{ + char filter[1024]; + int retval; + + if (!tevent->filter) + return; + + if (!tevent->filter_enabled) + return; + + debug_msg("Disabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); + + snprintf(filter, 1024, "!%s\n", tevent->filter); + + retval = tracefs_event_file_write(instance->inst, tevent->system, + tevent->event, "filter", filter); + if (retval < 0) + err_msg("Error disabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); +} + +/* + * trace_event_save_hist - save the content of an event hist + * + * If the trigger is a hist: one, save the content of the hist file. + */ +static void trace_event_save_hist(struct trace_instance *instance, + struct trace_events *tevent) +{ + int retval, index, out_fd; + mode_t mode = 0644; + char path[1024]; + char *hist; + + if (!tevent) + return; + + /* trigger enables hist */ + if (!tevent->trigger) + return; + + /* is this a hist: trigger? */ + retval = strncmp(tevent->trigger, "hist:", strlen("hist:")); + if (retval) + return; + + snprintf(path, 1024, "%s_%s_hist.txt", tevent->system, tevent->event); + + printf(" Saving event %s:%s hist to %s\n", tevent->system, tevent->event, path); + + out_fd = creat(path, mode); + if (out_fd < 0) { + err_msg(" Failed to create %s output file\n", path); + return; + } + + hist = tracefs_event_file_read(instance->inst, tevent->system, tevent->event, "hist", 0); + if (!hist) { + err_msg(" Failed to read %s:%s hist file\n", tevent->system, tevent->event); + goto out_close; + } + + index = 0; + do { + index += write(out_fd, &hist[index], strlen(hist) - index); + } while (index < strlen(hist)); + + free(hist); +out_close: + close(out_fd); +} + +/* + * trace_event_disable_trigger - disable an event trigger + */ +static void trace_event_disable_trigger(struct trace_instance *instance, + struct trace_events *tevent) +{ + char trigger[1024]; + int retval; + + if (!tevent->trigger) + return; + + if (!tevent->trigger_enabled) + return; + + debug_msg("Disabling %s:%s trigger %s\n", tevent->system, + tevent->event ? : "*", tevent->trigger); + + trace_event_save_hist(instance, tevent); + + snprintf(trigger, 1024, "!%s\n", tevent->trigger); + + retval = tracefs_event_file_write(instance->inst, tevent->system, + tevent->event, "trigger", trigger); + if (retval < 0) + err_msg("Error disabling %s:%s trigger %s\n", tevent->system, + tevent->event ? : "*", tevent->trigger); +} + +/* + * trace_events_disable - disable all trace events + */ +void trace_events_disable(struct trace_instance *instance, + struct trace_events *events) +{ + struct trace_events *tevent = events; + + if (!events) + return; + + while (tevent) { + debug_msg("Disabling event %s:%s\n", tevent->system, tevent->event ? : "*"); + if (tevent->enabled) { + trace_event_disable_filter(instance, tevent); + trace_event_disable_trigger(instance, tevent); + tracefs_event_disable(instance->inst, tevent->system, tevent->event); + } + + tevent->enabled = 0; + tevent = tevent->next; + } +} + +/* + * trace_event_enable_filter - enable an event filter associated with an event + */ +static int trace_event_enable_filter(struct trace_instance *instance, + struct trace_events *tevent) +{ + char filter[1024]; + int retval; + + if (!tevent->filter) + return 0; + + if (!tevent->event) { + err_msg("Filter %s applies only for single events, not for all %s:* events\n", + tevent->filter, tevent->system); + return 1; + } + + snprintf(filter, 1024, "%s\n", tevent->filter); + + debug_msg("Enabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); + + retval = tracefs_event_file_write(instance->inst, tevent->system, + tevent->event, "filter", filter); + if (retval < 0) { + err_msg("Error enabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); + return 1; + } + + tevent->filter_enabled = 1; + return 0; +} + +/* + * trace_event_enable_trigger - enable an event trigger associated with an event + */ +static int trace_event_enable_trigger(struct trace_instance *instance, + struct trace_events *tevent) +{ + char trigger[1024]; + int retval; + + if (!tevent->trigger) + return 0; + + if (!tevent->event) { + err_msg("Trigger %s applies only for single events, not for all %s:* events\n", + tevent->trigger, tevent->system); + return 1; + } + + snprintf(trigger, 1024, "%s\n", tevent->trigger); + + debug_msg("Enabling %s:%s trigger %s\n", tevent->system, + tevent->event ? : "*", tevent->trigger); + + retval = tracefs_event_file_write(instance->inst, tevent->system, + tevent->event, "trigger", trigger); + if (retval < 0) { + err_msg("Error enabling %s:%s trigger %s\n", tevent->system, + tevent->event ? : "*", tevent->trigger); + return 1; + } + + tevent->trigger_enabled = 1; + + return 0; +} + +/* + * trace_events_enable - enable all events + */ +int trace_events_enable(struct trace_instance *instance, + struct trace_events *events) +{ + struct trace_events *tevent = events; + int retval; + + while (tevent) { + debug_msg("Enabling event %s:%s\n", tevent->system, tevent->event ? : "*"); + retval = tracefs_event_enable(instance->inst, tevent->system, tevent->event); + if (retval < 0) { + err_msg("Error enabling event %s:%s\n", tevent->system, + tevent->event ? : "*"); + return 1; + } + + retval = trace_event_enable_filter(instance, tevent); + if (retval) + return 1; + + retval = trace_event_enable_trigger(instance, tevent); + if (retval) + return 1; + + tevent->enabled = 1; + tevent = tevent->next; + } + + return 0; +} + +/* + * trace_events_destroy - disable and free all trace events + */ +void trace_events_destroy(struct trace_instance *instance, + struct trace_events *events) +{ + if (!events) + return; + + trace_events_disable(instance, events); + trace_events_free(events); +} + +int trace_is_off(struct trace_instance *tool, struct trace_instance *trace) +{ + /* + * The tool instance is always present, it is the one used to collect + * data. + */ + if (!tracefs_trace_is_on(tool->inst)) + return 1; + + /* + * The trace instance is only enabled when -t is set. IOW, when the system + * is tracing. + */ + if (trace && !tracefs_trace_is_on(trace->inst)) + return 1; + + return 0; +} diff --git a/tools/tracing/rtla/src/trace.h b/tools/tracing/rtla/src/trace.h index 0ea1df0..2e9a89a 100644 --- a/tools/tracing/rtla/src/trace.h +++ b/tools/tracing/rtla/src/trace.h @@ -2,6 +2,17 @@ #include #include +struct trace_events { + struct trace_events *next; + char *system; + char *event; + char *filter; + char *trigger; + char enabled; + char filter_enabled; + char trigger_enabled; +}; + struct trace_instance { struct tracefs_instance *inst; struct tep_handle *tep; @@ -25,3 +36,15 @@ void destroy_instance(struct tracefs_instance *inst); int save_trace_to_file(struct tracefs_instance *inst, const char *filename); int collect_registered_events(struct tep_event *tep, struct tep_record *record, int cpu, void *context); + +struct trace_events *trace_event_alloc(const char *event_string); +void trace_events_disable(struct trace_instance *instance, + struct trace_events *events); +void trace_events_destroy(struct trace_instance *instance, + struct trace_events *events); +int trace_events_enable(struct trace_instance *instance, + struct trace_events *events); + +int trace_event_add_filter(struct trace_events *event, char *filter); +int trace_event_add_trigger(struct trace_events *event, char *trigger); +int trace_is_off(struct trace_instance *tool, struct trace_instance *trace); diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c index ffaf8ec..da2b590 100644 --- a/tools/tracing/rtla/src/utils.c +++ b/tools/tracing/rtla/src/utils.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -431,3 +432,35 @@ int parse_prio(char *arg, struct sched_attr *sched_param) } return 0; } + +/* + * set_cpu_dma_latency - set the /dev/cpu_dma_latecy + * + * This is used to reduce the exit from idle latency. The value + * will be reset once the file descriptor of /dev/cpu_dma_latecy + * is closed. + * + * Return: the /dev/cpu_dma_latecy file descriptor + */ +int set_cpu_dma_latency(int32_t latency) +{ + int retval; + int fd; + + fd = open("/dev/cpu_dma_latency", O_RDWR); + if (fd < 0) { + err_msg("Error opening /dev/cpu_dma_latency\n"); + return -1; + } + + retval = write(fd, &latency, 4); + if (retval < 1) { + err_msg("Error setting /dev/cpu_dma_latency\n"); + close(fd); + return -1; + } + + debug_msg("Set /dev/cpu_dma_latency to %d\n", latency); + + return fd; +} diff --git a/tools/tracing/rtla/src/utils.h b/tools/tracing/rtla/src/utils.h index 9aa9623..fa08e37 100644 --- a/tools/tracing/rtla/src/utils.h +++ b/tools/tracing/rtla/src/utils.h @@ -54,3 +54,4 @@ struct sched_attr { int parse_prio(char *arg, struct sched_attr *sched_param); int set_comm_sched_attr(const char *comm, struct sched_attr *attr); +int set_cpu_dma_latency(int32_t latency);