Add support for the --histogram and --histfile options as in cyclictest.
The short -h option is not supported, as cyclicdeadline already uses that
for help. -H/--histofall is not supported but could be easily added.
Signed-off-by: Crystal Wood <crwood@xxxxxxxxxx>
---
Given the recent request for oslat, do we want to be able to do ns-granularity
histograms? Or just stick with what cyclictest supports, as that's what rteval
wants?
Is histofall support needed? rteval doesn't use it.
---
src/sched_deadline/cyclicdeadline.c | 113 +++++++++++++++++++++++++---
1 file changed, 103 insertions(+), 10 deletions(-)
diff --git a/src/sched_deadline/cyclicdeadline.c b/src/sched_deadline/cyclicdeadline.c
index 097e2e5d4580..f45ec3d6394b 100644
--- a/src/sched_deadline/cyclicdeadline.c
+++ b/src/sched_deadline/cyclicdeadline.c
@@ -33,6 +33,7 @@
#include "rt-utils.h"
#include "rt-sched.h"
#include "rt-error.h"
+#include "histogram.h"
#define _STR(x) #x
#define STR(x) _STR(x)
@@ -40,6 +41,8 @@
#define MAXPATH 1024
#endif
+#define HIST_MAX 1000000
+
#define CPUSET_ALL "my_cpuset_all"
#define CPUSET_LOCAL "my_cpuset"
@@ -56,16 +59,13 @@ struct thread_stat {
long act;
double avg;
long *values;
- long *hist_array;
- long *outliers;
+ struct histogram *hist;
pthread_t thread;
int threadstarted;
int tid;
long reduce;
long redmax;
long cycleofmax;
- long hist_overflow;
- long num_outliers;
};
struct sched_data {
@@ -84,6 +84,8 @@ static int info_enable;
static int debug_enable;
static int tracelimit;
static int trace_marker;
+static int histogram;
+static FILE *histfile;
static pthread_mutex_t break_thread_id_lock = PTHREAD_MUTEX_INITIALIZER;
static pid_t break_thread_id;
static uint64_t break_thread_value;
@@ -97,6 +99,8 @@ static int mark_fd;
static int quiet;
static char jsonfile[MAX_PATH];
+static struct histoset hset;
+
static int find_mount(const char *mount, char *debugfs)
{
char type[100];
@@ -691,6 +695,10 @@ static void usage(int error)
" Append 'm', 'h', or 'd' to specify minutes, hours or\n"
" days\n"
"-h --help Show this help menu.\n"
+ " --histogram=US dump a latency histogram to stdout after the run\n"
+ " US is the max latency time to be tracked in microseconds\n"
+ " This option runs all threads at the same priority.\n"
+ " --histfile=<path> dump the latency histogram to <path> instead of stdout\n"
"-i INTV --interval The shortest deadline for the tasks in us\n"
" (default 1000us).\n"
" --json=FILENAME write final results into FILENAME, JSON formatted\n"
@@ -718,6 +726,55 @@ static u64 get_time_us(void)
return time;
}
+static void print_hist(FILE *fp, struct sched_data *sd, int nthreads)
+{
+ int i;
+ unsigned long maxmax, alloverflows;
+
+ fprintf(fp, "# Histogram\n");
+ for (i = 0; i < histogram; i++) {
+ unsigned long flags = 0;
+
+ fprintf(fp, "%06d ", i);
+
+ hset_print_bucket(&hset, fp, i, flags);
+ fprintf(fp, "\n");
+ }
+ fprintf(fp, "# Min Latencies:");
+ for (i = 0; i < nthreads; i++)
+ fprintf(fp, " %05lu", sd[i].stat.min);
+ fprintf(fp, "\n");
+ fprintf(fp, "# Avg Latencies:");
+ for (i = 0; i < nthreads; i++)
+ fprintf(fp, " %05lu", sd[i].stat.cycles ?
+ (long)(sd[i].stat.avg/sd[i].stat.cycles) : 0);
+ fprintf(fp, "\n");
+ fprintf(fp, "# Max Latencies:");
+ maxmax = 0;
+ for (i = 0; i < nthreads; i++) {
+ fprintf(fp, " %05lu", sd[i].stat.max);
+ if (sd[i].stat.max > maxmax)
+ maxmax = sd[i].stat.max;
+ }
+ fprintf(fp, "\n");
+ fprintf(fp, "# Histogram Overflows:");
+ alloverflows = 0;
+ for (i = 0; i < nthreads; i++) {
+ fprintf(fp, " %05lu", sd[i].stat.hist->oflow_count);
+ alloverflows += sd[i].stat.hist->oflow_count;
+ }
+ fprintf(fp, "\n");
+
+ fprintf(fp, "# Histogram Overflow at cycle number:\n");
+ for (i = 0; i < nthreads; i++) {
+ fprintf(fp, "# Thread %d: ", i);
+ hist_print_oflows(sd[i].stat.hist, fp);
+ fprintf(fp, "\n");
+ }
+
+ fprintf(fp, "\n");
+}
+
static void print_stat(FILE *fp, struct sched_data *sd, int index, int verbose, int quiet)
{
struct thread_stat *stat = &sd->stat;
@@ -784,6 +841,9 @@ static u64 do_runtime(struct sched_data *sd, u64 period)
stat->act = diff;
stat->avg += (double) diff;
+ if (histogram)
+ hist_sample(stat->hist, diff);
+
stat->cycles++;
return next_period;
@@ -1058,8 +1118,13 @@ static void loop(struct sched_data *sched_data, int nr_threads)
if (!quiet) {
printf("\033[%dB", nr_threads + 2);
} else {
- for (i = 0; i < nr_threads; ++i)
- print_stat(stdout, &sched_data[i], i, 0, 0);
+ if (histogram) {
+ FILE *out = histfile ? histfile : stdout;
+ print_hist(out, sched_data, nr_threads);
+ } else {
+ for (i = 0; i < nr_threads; ++i)
+ print_stat(stdout, &sched_data[i], i, 0, 0);
+ }
}
}
@@ -1075,10 +1140,14 @@ static void write_stats(FILE *f, void *data)
for (i = 0; i < nr_threads; i++) {
s = &sd[i].stat;
fprintf(f, " \"%u\": {\n", i);
- fprintf(f, " \"cycles\": %ld,\n", s->cycles);
- fprintf(f, " \"min\": %ld,\n", s->min);
- fprintf(f, " \"max\": %ld,\n", s->max);
- fprintf(f, " \"avg\": %.2f\n", s->avg/s->cycles);
+
+ fprintf(f, " \"histogram\": {");
+ hist_print_json(s->hist, f);
+ fprintf(f, " },\n");
+ fprintf(f, " \"cycles\": %ld,\n", s->cycles);
+ fprintf(f, " \"min\": %ld,\n", s->min);
+ fprintf(f, " \"max\": %ld,\n", s->max);
+ fprintf(f, " \"avg\": %.2f\n", s->avg/s->cycles);
fprintf(f, " }%s\n", i == nr_threads - 1 ? "" : ",");
}
fprintf(f, " }\n");
@@ -1088,6 +1157,7 @@ enum options_values {
OPT_AFFINITY=1, OPT_DURATION, OPT_HELP, OPT_INTERVAL,
OPT_JSON, OPT_STEP, OPT_THREADS, OPT_QUIET,
OPT_BREAKTRACE, OPT_TRACEMARK, OPT_INFO, OPT_DEBUG,
+ OPT_HISTOGRAM, OPT_HISTFILE
};
int main(int argc, char **argv)
@@ -1130,6 +1200,8 @@ int main(int argc, char **argv)
{ "tracemark", no_argument, NULL, OPT_TRACEMARK },
{ "verbose", no_argument, NULL, OPT_INFO},
{ "debug", no_argument, NULL, OPT_DEBUG},
+ { "histogram", required_argument, NULL, OPT_HISTOGRAM },
+ { "histfile", required_argument, NULL, OPT_HISTFILE },
{ NULL, 0, NULL, 0 },
};
c = getopt_long(argc, argv, "a::c:D:hi:s:t:b:q", options, NULL);
@@ -1188,6 +1260,17 @@ int main(int argc, char **argv)
case OPT_DEBUG:
debug_enable = 1;
break;
+ case OPT_HISTOGRAM:
+ histogram = atoi(optarg);
+ if (histogram <= 0 || histogram > HIST_MAX)
+ usage(1);
+ break;
+ case OPT_HISTFILE:
+ histfile = fopen(optarg, "w");
+ if (!histfile)
+ fatal("Couldn\'t open histfile %s: %s\n",
+ optarg, strerror(errno));
+ break;
default:
usage(1);
}
@@ -1233,6 +1316,10 @@ int main(int argc, char **argv)
if (!thread || !sched_data)
fatal("allocating threads");
+ if (histogram && hset_init(&hset, nr_threads, 1, histogram, histogram))
+ fatal("failed to allocate histogram of size %d for %d threads\n",
+ histogram, nr_threads);
+
if (nr_threads > nr_cpus) {
/*
* More threads than CPUs, then have the total be
@@ -1262,6 +1349,9 @@ int main(int argc, char **argv)
sd->runtime_us = runtime;
sd->deadline_us = interval;
+ if (histogram)
+ sd->stat.hist = &hset.histos[i];
+
info(info_enable, "interval: %lld:%lld\n", sd->runtime_us, sd->deadline_us);
/* Make sure that we can make our deadlines */
@@ -1356,6 +1446,9 @@ int main(int argc, char **argv)
free(setcpu_buf);
free(thread);
free(sched_data);
+ if (histfile)
+ fclose(histfile);
+ hset_destroy(&hset);
return 0;
}
--
2.43.0
