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rtl_test: refactoring and optimization for PPM error

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Signed-off-by: Steve Markgraf <steve@steve-m.de>
This commit is contained in:
Michael Tatarinov 2014-01-30 08:21:44 +04:00 committed by Steve Markgraf
parent 2c171630fa
commit 1cc9d64d98
1 changed files with 96 additions and 90 deletions
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186
src/rtl_test.c
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@ -48,28 +48,23 @@
#define MHZ(x) ((x)*1000*1000) #define MHZ(x) ((x)*1000*1000)
#define PPM_DURATION 10 #define PPM_DURATION 10
#define PPM_DUMP_TIME 5
static enum {
NO_BENCHMARK,
TUNER_BENCHMARK,
PPM_BENCHMARK
} test_mode = NO_BENCHMARK;
static int do_exit = 0; static int do_exit = 0;
static rtlsdr_dev_t *dev = NULL; static rtlsdr_dev_t *dev = NULL;
static int ppm_benchmark = 0; static uint32_t samp_rate = DEFAULT_SAMPLE_RATE;
static int ppm_running = 0;
static int64_t ppm_count = 0L;
static int64_t ppm_total = 0L;
uint32_t samp_rate = DEFAULT_SAMPLE_RATE;
long total_samples; static uint32_t total_samples = 0;
long dropped_samples; static uint32_t dropped_samples = 0;
#ifndef _WIN32 static unsigned int ppm_duration = PPM_DURATION;
static struct timespec ppm_start;
static struct timespec ppm_recent;
static struct timespec ppm_now;
#endif
#ifdef __APPLE__
static struct timeval tv;
#endif
void usage(void) void usage(void)
{ {
@ -79,9 +74,9 @@ void usage(void)
"\t[-s samplerate (default: 2048000 Hz)]\n" "\t[-s samplerate (default: 2048000 Hz)]\n"
"\t[-d device_index (default: 0)]\n" "\t[-d device_index (default: 0)]\n"
"\t[-t enable Elonics E4000 tuner benchmark]\n" "\t[-t enable Elonics E4000 tuner benchmark]\n"
#ifndef _WIN32 #ifndef _WIN32
"\t[-p enable PPM error measurement]\n" "\t[-p[seconds] enable PPM error measurement (default: 10 seconds)]\n"
#endif #endif
"\t[-b output_block_size (default: 16 * 16384)]\n" "\t[-b output_block_size (default: 16 * 16384)]\n"
"\t[-S force sync output (default: async)]\n"); "\t[-S force sync output (default: async)]\n");
exit(1); exit(1);
@ -126,8 +121,8 @@ static void underrun_test(unsigned char *buf, uint32_t len, int mute)
bcnt++; bcnt++;
} }
total_samples += (long)len; total_samples += len;
dropped_samples += (long)lost; dropped_samples += lost;
if (mute) if (mute)
return; return;
if (lost) if (lost)
@ -135,77 +130,92 @@ static void underrun_test(unsigned char *buf, uint32_t len, int mute)
} }
static void ppm_clock_init(void) #ifndef _WIN32
static int ppm_gettime(struct timespec *ts)
{ {
#ifdef __APPLE__ int rv = ENOSYS;
gettimeofday(&tv, NULL);
ppm_recent.tv_sec = tv.tv_sec; #ifdef __unix__
ppm_recent.tv_nsec = tv.tv_usec*1000; rv = clock_gettime(CLOCK_MONOTONIC, ts);
ppm_start.tv_sec = tv.tv_sec; #elif __APPLE__
ppm_start.tv_nsec = tv.tv_usec*1000; struct timeval tv;
#elif __unix__
clock_gettime(CLOCK_REALTIME, &ppm_recent); rv = gettimeofday(&tv, NULL);
clock_gettime(CLOCK_REALTIME, &ppm_start); ts->tv_sec = tv.tv_sec;
ts->tv_nsec = tv.tv_usec * 1000;
#endif #endif
return rv;
} }
#ifndef _WIN32 static int ppm_report(uint64_t nsamples, uint64_t interval)
static int ppm_report(void)
{ {
int real_rate; double real_rate, ppm;
int64_t ns;
ns = 1000000000L * (int64_t)(ppm_recent.tv_sec - ppm_start.tv_sec); real_rate = nsamples * 1e9 / interval;
ns += (int64_t)(ppm_recent.tv_nsec - ppm_start.tv_nsec); ppm = 1e6 * (real_rate / (double)samp_rate - 1.);
real_rate = (int)(ppm_total * 1000000000L / ns); return (int)round(ppm);
return (int)round((double)(1000000 * (real_rate - (int)samp_rate)) / (double)samp_rate);
} }
#endif
static void ppm_test(uint32_t len) static void ppm_test(uint32_t len)
{ {
int64_t ns; static uint64_t nsamples = 0;
static uint64_t interval = 0;
static uint64_t nsamples_total = 0;
static uint64_t interval_total = 0;
struct timespec ppm_now;
static struct timespec ppm_recent;
static enum {
PPM_INIT_NO,
PPM_INIT_DUMP,
PPM_INIT_RUN
} ppm_init = PPM_INIT_NO;
ppm_count += (int64_t)len; ppm_gettime(&ppm_now);
#ifndef _WIN32 if (ppm_init != PPM_INIT_RUN) {
#ifndef __APPLE__ /*
clock_gettime(CLOCK_REALTIME, &ppm_now); * Kyle Keen wrote:
#else * PPM_DUMP_TIME throws out the first N seconds of data.
gettimeofday(&tv, NULL); * The dongle's PPM is usually very bad when first starting up,
ppm_now.tv_sec = tv.tv_sec; * typically incorrect by more than twice the final value.
ppm_now.tv_nsec = tv.tv_usec*1000; * Discarding the first few seconds allows the value to stabilize much faster.
#endif */
if (ppm_now.tv_sec - ppm_recent.tv_sec > PPM_DURATION) { if (ppm_init == PPM_INIT_NO) {
ns = 1000000000L * (int64_t)(ppm_now.tv_sec - ppm_recent.tv_sec); ppm_recent.tv_sec = ppm_now.tv_sec + PPM_DUMP_TIME;
ns += (int64_t)(ppm_now.tv_nsec - ppm_recent.tv_nsec); ppm_init = PPM_INIT_DUMP;
printf("real sample rate: %i", return;
(int)((1000000000L * ppm_count / 2L) / ns)); }
#ifndef __APPLE__ if (ppm_init == PPM_INIT_DUMP && ppm_recent.tv_sec < ppm_now.tv_sec)
clock_gettime(CLOCK_REALTIME, &ppm_recent); return;
#else ppm_recent.tv_sec = ppm_now.tv_sec;
gettimeofday(&tv, NULL); ppm_recent.tv_nsec = ppm_now.tv_nsec;
ppm_recent.tv_sec = tv.tv_sec; ppm_init = PPM_INIT_RUN;
ppm_recent.tv_nsec = tv.tv_usec*1000; return;
#endif
ppm_total += ppm_count / 2L;
ppm_count = 0L;
printf(" cumulative ppm: %i\n", ppm_report());
} }
#endif nsamples += (uint64_t)(len / 2UL);
interval = (uint64_t)(ppm_now.tv_sec - ppm_recent.tv_sec);
if (interval < ppm_duration)
return;
interval *= 1000000000UL;
interval += (int64_t)(ppm_now.tv_nsec - ppm_recent.tv_nsec);
nsamples_total += nsamples;
interval_total += interval;
printf("real sample rate: %i current PPM: %i cumulative PPM: %i\n",
(int)((1000000000UL * nsamples) / interval),
ppm_report(nsamples, interval),
ppm_report(nsamples_total, interval_total));
ppm_recent.tv_sec = ppm_now.tv_sec;
ppm_recent.tv_nsec = ppm_now.tv_nsec;
nsamples = 0;
} }
#endif
static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx) static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
{ {
underrun_test(buf, len, 0); underrun_test(buf, len, 0);
#ifndef _WIN32
if (ppm_benchmark && !ppm_running) { if (test_mode == PPM_BENCHMARK)
ppm_clock_init();
ppm_running = 1;
return;
}
if (ppm_benchmark) {
ppm_test(len); ppm_test(len);
} #endif
} }
void e4k_benchmark(void) void e4k_benchmark(void)
@ -259,9 +269,7 @@ int main(int argc, char **argv)
#ifndef _WIN32 #ifndef _WIN32
struct sigaction sigact; struct sigaction sigact;
#endif #endif
int n_read; int n_read, r, opt, i;
int r, opt;
int i, tuner_benchmark = 0;
int sync_mode = 0; int sync_mode = 0;
uint8_t *buffer; uint8_t *buffer;
int dev_index = 0; int dev_index = 0;
@ -270,7 +278,7 @@ int main(int argc, char **argv)
int count; int count;
int gains[100]; int gains[100];
while ((opt = getopt(argc, argv, "d:s:b:tpS::")) != -1) { while ((opt = getopt(argc, argv, "d:s:b:tp::Sh")) != -1) {
switch (opt) { switch (opt) {
case 'd': case 'd':
dev_index = verbose_device_search(optarg); dev_index = verbose_device_search(optarg);
@ -283,14 +291,17 @@ int main(int argc, char **argv)
out_block_size = (uint32_t)atof(optarg); out_block_size = (uint32_t)atof(optarg);
break; break;
case 't': case 't':
tuner_benchmark = 1; test_mode = TUNER_BENCHMARK;
break; break;
case 'p': case 'p':
ppm_benchmark = PPM_DURATION; test_mode = PPM_BENCHMARK;
if (optarg)
ppm_duration = atoi(optarg);
break; break;
case 'S': case 'S':
sync_mode = 1; sync_mode = 1;
break; break;
case 'h':
default: default:
usage(); usage();
break; break;
@ -345,7 +356,7 @@ int main(int argc, char **argv)
/* Set the sample rate */ /* Set the sample rate */
verbose_set_sample_rate(dev, samp_rate); verbose_set_sample_rate(dev, samp_rate);
if (tuner_benchmark) { if (test_mode == TUNER_BENCHMARK) {
if (rtlsdr_get_tuner_type(dev) == RTLSDR_TUNER_E4000) if (rtlsdr_get_tuner_type(dev) == RTLSDR_TUNER_E4000)
e4k_benchmark(); e4k_benchmark();
else else
@ -360,12 +371,12 @@ int main(int argc, char **argv)
/* Reset endpoint before we start reading from it (mandatory) */ /* Reset endpoint before we start reading from it (mandatory) */
verbose_reset_buffer(dev); verbose_reset_buffer(dev);
if (ppm_benchmark && !sync_mode) { if ((test_mode == PPM_BENCHMARK) && !sync_mode) {
fprintf(stderr, "Reporting PPM error measurement every %i seconds...\n", ppm_benchmark); fprintf(stderr, "Reporting PPM error measurement every %i seconds...\n", ppm_duration);
fprintf(stderr, "Press ^C after a few minutes.\n"); fprintf(stderr, "Press ^C after a few minutes.\n");
} }
if (!ppm_benchmark) { if (test_mode == NO_BENCHMARK) {
fprintf(stderr, "\nInfo: This tool will continuously" fprintf(stderr, "\nInfo: This tool will continuously"
" read from the device, and report if\n" " read from the device, and report if\n"
"samples get lost. If you observe no " "samples get lost. If you observe no "
@ -397,11 +408,6 @@ int main(int argc, char **argv)
if (do_exit) { if (do_exit) {
fprintf(stderr, "\nUser cancel, exiting...\n"); fprintf(stderr, "\nUser cancel, exiting...\n");
fprintf(stderr, "Samples per million lost (minimum): %i\n", (int)(1000000L * dropped_samples / total_samples)); fprintf(stderr, "Samples per million lost (minimum): %i\n", (int)(1000000L * dropped_samples / total_samples));
#ifndef _WIN32
if (ppm_benchmark) {
printf("Cumulative PPM error: %i\n", ppm_report());
}
#endif
} }
else else
fprintf(stderr, "\nLibrary error %d, exiting...\n", r); fprintf(stderr, "\nLibrary error %d, exiting...\n", r);