// SPDX-License-Identifier: GPL-2.0/* * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org> */ #include <getopt.h>#include <stdlib.h>#include <string.h>#include <signal.h>#include <unistd.h>#include <stdio.h>#include <time.h> #include "utils.h"#include "osnoise.h"#include "timerlat.h" struct timerlat_hist_params { char *cpus; char *monitored_cpus; char *trace_output; unsigned long long runtime; long long stop_us; long long stop_total_us; long long timerlat_period_us; long long print_stack; int sleep_time; 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; char no_header; char no_summary; char no_index; char with_zeros; int bucket_size; int entries;}; struct timerlat_hist_cpu { int *irq; int *thread; int irq_count; int thread_count; unsigned long long min_irq; unsigned long long sum_irq; unsigned long long max_irq; unsigned long long min_thread; unsigned long long sum_thread; unsigned long long max_thread;}; struct timerlat_hist_data { struct timerlat_hist_cpu *hist; int entries; int bucket_size; int nr_cpus;}; /* * timerlat_free_histogram - free runtime data */static voidtimerlat_free_histogram(struct timerlat_hist_data *data){ int cpu; /* one histogram for IRQ and one for thread, per CPU */ for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (data->hist[cpu].irq) free(data->hist[cpu].irq); if (data->hist[cpu].thread) free(data->hist[cpu].thread); } /* one set of histograms per CPU */ if (data->hist) free(data->hist); free(data);} /* * timerlat_alloc_histogram - alloc runtime data */static struct timerlat_hist_data*timerlat_alloc_histogram(int nr_cpus, int entries, int bucket_size){ struct timerlat_hist_data *data; int cpu; data = calloc(1, sizeof(*data)); if (!data) return NULL; data->entries = entries; data->bucket_size = bucket_size; data->nr_cpus = nr_cpus; /* one set of histograms per CPU */ data->hist = calloc(1, sizeof(*data->hist) * nr_cpus); if (!data->hist) goto cleanup; /* one histogram for IRQ and one for thread, per cpu */ for (cpu = 0; cpu < nr_cpus; cpu++) { data->hist[cpu].irq = calloc(1, sizeof(*data->hist->irq) * (entries + 1)); if (!data->hist[cpu].irq) goto cleanup; data->hist[cpu].thread = calloc(1, sizeof(*data->hist->thread) * (entries + 1)); if (!data->hist[cpu].thread) goto cleanup; } /* set the min to max */ for (cpu = 0; cpu < nr_cpus; cpu++) { data->hist[cpu].min_irq = ~0; data->hist[cpu].min_thread = ~0; } return data; cleanup: timerlat_free_histogram(data); return NULL;} /* * timerlat_hist_update - record a new timerlat occurent on cpu, updating data */static voidtimerlat_hist_update(struct osnoise_tool *tool, int cpu, unsigned long long thread, unsigned long long latency){ struct timerlat_hist_params *params = tool->params; struct timerlat_hist_data *data = tool->data; int entries = data->entries; int bucket; int *hist; if (params->output_divisor) latency = latency / params->output_divisor; if (data->bucket_size) bucket = latency / data->bucket_size; if (!thread) { hist = data->hist[cpu].irq; data->hist[cpu].irq_count++; update_min(&data->hist[cpu].min_irq, &latency); update_sum(&data->hist[cpu].sum_irq, &latency); update_max(&data->hist[cpu].max_irq, &latency); } else { hist = data->hist[cpu].thread; data->hist[cpu].thread_count++; update_min(&data->hist[cpu].min_thread, &latency); update_sum(&data->hist[cpu].sum_thread, &latency); update_max(&data->hist[cpu].max_thread, &latency); } if (bucket < entries) hist[bucket]++; else hist[entries]++;} /* * timerlat_hist_handler - this is the handler for timerlat tracer events */static inttimerlat_hist_handler(struct trace_seq *s, struct tep_record *record, struct tep_event *event, void *data){ struct trace_instance *trace = data; unsigned long long thread, latency; struct osnoise_tool *tool; int cpu = record->cpu; tool = container_of(trace, struct osnoise_tool, trace); tep_get_field_val(s, event, "context", record, &thread, 1); tep_get_field_val(s, event, "timer_latency", record, &latency, 1); timerlat_hist_update(tool, cpu, thread, latency); return 0;} /* * timerlat_hist_header - print the header of the tracer to the output */static void timerlat_hist_header(struct osnoise_tool *tool){ struct timerlat_hist_params *params = tool->params; struct timerlat_hist_data *data = tool->data; struct trace_seq *s = tool->trace.seq; char duration[26]; int cpu; if (params->no_header) return; get_duration(tool->start_time, duration, sizeof(duration)); trace_seq_printf(s, "# RTLA timerlat histogram\n"); trace_seq_printf(s, "# Time unit is %s (%s)\n", params->output_divisor == 1 ? "nanoseconds" : "microseconds", params->output_divisor == 1 ? "ns" : "us"); trace_seq_printf(s, "# Duration: %s\n", duration); if (!params->no_index) trace_seq_printf(s, "Index"); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(s, " IRQ-%03d", cpu); if (!params->no_thread) trace_seq_printf(s, " Thr-%03d", cpu); } trace_seq_printf(s, "\n"); trace_seq_do_printf(s); trace_seq_reset(s);} /* * timerlat_print_summary - print the summary of the hist data to the output */static voidtimerlat_print_summary(struct timerlat_hist_params *params, struct trace_instance *trace, struct timerlat_hist_data *data){ int cpu; if (params->no_summary) return; if (!params->no_index) trace_seq_printf(trace->seq, "count:"); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].irq_count); if (!params->no_thread) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].thread_count); } trace_seq_printf(trace->seq, "\n"); if (!params->no_index) trace_seq_printf(trace->seq, "min: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].min_irq); if (!params->no_thread) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].min_thread); } trace_seq_printf(trace->seq, "\n"); if (!params->no_index) trace_seq_printf(trace->seq, "avg: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) { if (data->hist[cpu].irq_count) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].sum_irq / data->hist[cpu].irq_count); else trace_seq_printf(trace->seq, " - "); } if (!params->no_thread) { if (data->hist[cpu].thread_count) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].sum_thread / data->hist[cpu].thread_count); else trace_seq_printf(trace->seq, " - "); } } trace_seq_printf(trace->seq, "\n"); if (!params->no_index) trace_seq_printf(trace->seq, "max: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].max_irq); if (!params->no_thread) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].max_thread); } trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq); trace_seq_reset(trace->seq);} /* * timerlat_print_stats - print data for all CPUs */static voidtimerlat_print_stats(struct timerlat_hist_params *params, struct osnoise_tool *tool){ struct timerlat_hist_data *data = tool->data; struct trace_instance *trace = &tool->trace; int bucket, cpu; int total; timerlat_hist_header(tool); for (bucket = 0; bucket < data->entries; bucket++) { total = 0; if (!params->no_index) trace_seq_printf(trace->seq, "%-6d", bucket * data->bucket_size); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) { total += data->hist[cpu].irq[bucket]; trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].irq[bucket]); } if (!params->no_thread) { total += data->hist[cpu].thread[bucket]; trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].thread[bucket]); } } if (total == 0 && !params->with_zeros) { trace_seq_reset(trace->seq); continue; } trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq); trace_seq_reset(trace->seq); } if (!params->no_index) trace_seq_printf(trace->seq, "over: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].irq[data->entries]); if (!params->no_thread) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].thread[data->entries]); } trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq); trace_seq_reset(trace->seq); timerlat_print_summary(params, trace, data);} /* * timerlat_hist_usage - prints timerlat top usage message */static void timerlat_hist_usage(char *usage){ int i; char *msg[] = { "", " 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 <filter>] [--trigger <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", " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us", " -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]", " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed", " --filter <filter>: enable a trace event filter to the previous -e event", " --trigger <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)", " --no-irq: ignore IRQ latencies", " --no-thread: ignore thread latencies", " --no-header: do not print header", " --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 <us> 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", " f:prio - use SCHED_FIFO with prio", " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period", " in nanoseconds", NULL, }; if (usage) fprintf(stderr, "%s\n", usage); fprintf(stderr, "rtla timerlat hist: a per-cpu histogram of the timer latency (version %s)\n", VERSION); for (i = 0; msg[i]; i++) fprintf(stderr, "%s\n", msg[i]); exit(1);} /* * timerlat_hist_parse_args - allocs, parse and fill the cmd line parameters */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; params = calloc(1, sizeof(*params)); if (!params) exit(1); /* disabled by default */ params->dma_latency = -1; /* display data in microseconds */Lines 1–500 of 914. 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// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org> */ #include <getopt.h> #include <stdlib.h> #include <string.h> #include <signal.h> #include <unistd.h> #include <stdio.h> #include <time.h> #include "utils.h" #include "osnoise.h" #include "timerlat.h" struct timerlat_hist_params { char *cpus; char *monitored_cpus; char *trace_output; unsigned long long runtime; long long stop_us; long long stop_total_us; long long timerlat_period_us; long long print_stack; int sleep_time; 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; char no_header; char no_summary; char no_index; char with_zeros; int bucket_size; int entries; }; struct timerlat_hist_cpu { int *irq; int *thread; int irq_count; int thread_count; unsigned long long min_irq; unsigned long long sum_irq; unsigned long long max_irq; unsigned long long min_thread; unsigned long long sum_thread; unsigned long long max_thread; }; struct timerlat_hist_data { struct timerlat_hist_cpu *hist; int entries; int bucket_size; int nr_cpus; }; /* * timerlat_free_histogram - free runtime data */ static void timerlat_free_histogram(struct timerlat_hist_data *data) { int cpu; /* one histogram for IRQ and one for thread, per CPU */ for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (data->hist[cpu].irq) free(data->hist[cpu].irq); if (data->hist[cpu].thread) free(data->hist[cpu].thread); } /* one set of histograms per CPU */ if (data->hist) free(data->hist); free(data); } /* * timerlat_alloc_histogram - alloc runtime data */ static struct timerlat_hist_data *timerlat_alloc_histogram(int nr_cpus, int entries, int bucket_size) { struct timerlat_hist_data *data; int cpu; data = calloc(1, sizeof(*data)); if (!data) return NULL; data->entries = entries; data->bucket_size = bucket_size; data->nr_cpus = nr_cpus; /* one set of histograms per CPU */ data->hist = calloc(1, sizeof(*data->hist) * nr_cpus); if (!data->hist) goto cleanup; /* one histogram for IRQ and one for thread, per cpu */ for (cpu = 0; cpu < nr_cpus; cpu++) { data->hist[cpu].irq = calloc(1, sizeof(*data->hist->irq) * (entries + 1)); if (!data->hist[cpu].irq) goto cleanup; data->hist[cpu].thread = calloc(1, sizeof(*data->hist->thread) * (entries + 1)); if (!data->hist[cpu].thread) goto cleanup; } /* set the min to max */ for (cpu = 0; cpu < nr_cpus; cpu++) { data->hist[cpu].min_irq = ~0; data->hist[cpu].min_thread = ~0; } return data; cleanup: timerlat_free_histogram(data); return NULL; } /* * timerlat_hist_update - record a new timerlat occurent on cpu, updating data */ static void timerlat_hist_update(struct osnoise_tool *tool, int cpu, unsigned long long thread, unsigned long long latency) { struct timerlat_hist_params *params = tool->params; struct timerlat_hist_data *data = tool->data; int entries = data->entries; int bucket; int *hist; if (params->output_divisor) latency = latency / params->output_divisor; if (data->bucket_size) bucket = latency / data->bucket_size; if (!thread) { hist = data->hist[cpu].irq; data->hist[cpu].irq_count++; update_min(&data->hist[cpu].min_irq, &latency); update_sum(&data->hist[cpu].sum_irq, &latency); update_max(&data->hist[cpu].max_irq, &latency); } else { hist = data->hist[cpu].thread; data->hist[cpu].thread_count++; update_min(&data->hist[cpu].min_thread, &latency); update_sum(&data->hist[cpu].sum_thread, &latency); update_max(&data->hist[cpu].max_thread, &latency); } if (bucket < entries) hist[bucket]++; else hist[entries]++; } /* * timerlat_hist_handler - this is the handler for timerlat tracer events */ static int timerlat_hist_handler(struct trace_seq *s, struct tep_record *record, struct tep_event *event, void *data) { struct trace_instance *trace = data; unsigned long long thread, latency; struct osnoise_tool *tool; int cpu = record->cpu; tool = container_of(trace, struct osnoise_tool, trace); tep_get_field_val(s, event, "context", record, &thread, 1); tep_get_field_val(s, event, "timer_latency", record, &latency, 1); timerlat_hist_update(tool, cpu, thread, latency); return 0; } /* * timerlat_hist_header - print the header of the tracer to the output */ static void timerlat_hist_header(struct osnoise_tool *tool) { struct timerlat_hist_params *params = tool->params; struct timerlat_hist_data *data = tool->data; struct trace_seq *s = tool->trace.seq; char duration[26]; int cpu; if (params->no_header) return; get_duration(tool->start_time, duration, sizeof(duration)); trace_seq_printf(s, "# RTLA timerlat histogram\n"); trace_seq_printf(s, "# Time unit is %s (%s)\n", params->output_divisor == 1 ? "nanoseconds" : "microseconds", params->output_divisor == 1 ? "ns" : "us"); trace_seq_printf(s, "# Duration: %s\n", duration); if (!params->no_index) trace_seq_printf(s, "Index"); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(s, " IRQ-%03d", cpu); if (!params->no_thread) trace_seq_printf(s, " Thr-%03d", cpu); } trace_seq_printf(s, "\n"); trace_seq_do_printf(s); trace_seq_reset(s); } /* * timerlat_print_summary - print the summary of the hist data to the output */ static void timerlat_print_summary(struct timerlat_hist_params *params, struct trace_instance *trace, struct timerlat_hist_data *data) { int cpu; if (params->no_summary) return; if (!params->no_index) trace_seq_printf(trace->seq, "count:"); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].irq_count); if (!params->no_thread) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].thread_count); } trace_seq_printf(trace->seq, "\n"); if (!params->no_index) trace_seq_printf(trace->seq, "min: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].min_irq); if (!params->no_thread) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].min_thread); } trace_seq_printf(trace->seq, "\n"); if (!params->no_index) trace_seq_printf(trace->seq, "avg: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) { if (data->hist[cpu].irq_count) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].sum_irq / data->hist[cpu].irq_count); else trace_seq_printf(trace->seq, " - "); } if (!params->no_thread) { if (data->hist[cpu].thread_count) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].sum_thread / data->hist[cpu].thread_count); else trace_seq_printf(trace->seq, " - "); } } trace_seq_printf(trace->seq, "\n"); if (!params->no_index) trace_seq_printf(trace->seq, "max: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].max_irq); if (!params->no_thread) trace_seq_printf(trace->seq, "%9llu ", data->hist[cpu].max_thread); } trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq); trace_seq_reset(trace->seq); } /* * timerlat_print_stats - print data for all CPUs */ static void timerlat_print_stats(struct timerlat_hist_params *params, struct osnoise_tool *tool) { struct timerlat_hist_data *data = tool->data; struct trace_instance *trace = &tool->trace; int bucket, cpu; int total; timerlat_hist_header(tool); for (bucket = 0; bucket < data->entries; bucket++) { total = 0; if (!params->no_index) trace_seq_printf(trace->seq, "%-6d", bucket * data->bucket_size); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) { total += data->hist[cpu].irq[bucket]; trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].irq[bucket]); } if (!params->no_thread) { total += data->hist[cpu].thread[bucket]; trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].thread[bucket]); } } if (total == 0 && !params->with_zeros) { trace_seq_reset(trace->seq); continue; } trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq); trace_seq_reset(trace->seq); } if (!params->no_index) trace_seq_printf(trace->seq, "over: "); for (cpu = 0; cpu < data->nr_cpus; cpu++) { if (params->cpus && !params->monitored_cpus[cpu]) continue; if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; if (!params->no_irq) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].irq[data->entries]); if (!params->no_thread) trace_seq_printf(trace->seq, "%9d ", data->hist[cpu].thread[data->entries]); } trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq); trace_seq_reset(trace->seq); timerlat_print_summary(params, trace, data); } /* * timerlat_hist_usage - prints timerlat top usage message */ static void timerlat_hist_usage(char *usage) { int i; char *msg[] = { "", " 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 <filter>] [--trigger <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", " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us", " -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]", " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed", " --filter <filter>: enable a trace event filter to the previous -e event", " --trigger <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)", " --no-irq: ignore IRQ latencies", " --no-thread: ignore thread latencies", " --no-header: do not print header", " --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 <us> 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", " f:prio - use SCHED_FIFO with prio", " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period", " in nanoseconds", NULL, }; if (usage) fprintf(stderr, "%s\n", usage); fprintf(stderr, "rtla timerlat hist: a per-cpu histogram of the timer latency (version %s)\n", VERSION); for (i = 0; msg[i]; i++) fprintf(stderr, "%s\n", msg[i]); exit(1); } /* * timerlat_hist_parse_args - allocs, parse and fill the cmd line parameters */ 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; params = calloc(1, sizeof(*params)); if (!params) exit(1); /* disabled by default */ params->dma_latency = -1; /* display data in microseconds */