diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2018-08-08 15:17:08 +0100 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2018-08-31 14:47:07 +0100 |
| commit | 5800e46c6f851c370c944a7cb169e99657239f8d (patch) | |
| tree | 74c3b5ab3a24b488c52706286470cacb4c2d0ec3 /tests/perf_pmu.c | |
| parent | 1754cbd35005605a80b06d808b4f891555a151cd (diff) | |
igt/perf_pmu: Improve the presentation of the accuracy calibration
Normalize the variance to stddev, and remove some redundant steps in
computing the time from itself.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Diffstat (limited to 'tests/perf_pmu.c')
| -rw-r--r-- | tests/perf_pmu.c | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/tests/perf_pmu.c b/tests/perf_pmu.c index 5a26d527..6ab2595b 100644 --- a/tests/perf_pmu.c +++ b/tests/perf_pmu.c @@ -1577,8 +1577,8 @@ accuracy(int gem_fd, const struct intel_execution_engine2 *e, /* 1st pass is calibration, second pass is the test. */ for (int pass = 0; pass < ARRAY_SIZE(timeout); pass++) { unsigned int target_idle_us = idle_us; - uint64_t busy_ns = 0, idle_ns = 0; struct timespec start = { }; + uint64_t busy_ns = 0; unsigned long pass_ns = 0; double avg = 0.0, var = 0.0; unsigned int n = 0; @@ -1589,6 +1589,7 @@ accuracy(int gem_fd, const struct intel_execution_engine2 *e, unsigned long loop_ns, loop_busy; struct timespec _ts = { }; double err, tmp; + uint64_t now; /* PWM idle sleep. */ _ts.tv_nsec = target_idle_us * 1000; @@ -1605,14 +1606,13 @@ accuracy(int gem_fd, const struct intel_execution_engine2 *e, igt_spin_batch_end(spin); /* Time accounting. */ - loop_ns = igt_nsec_elapsed(&start); - loop_busy = loop_ns - loop_busy; - loop_ns -= pass_ns; + now = igt_nsec_elapsed(&start); + loop_busy = now - loop_busy; + loop_ns = now - pass_ns; + pass_ns = now; busy_ns += loop_busy; total_busy_ns += loop_busy; - idle_ns += loop_ns - loop_busy; - pass_ns += loop_ns; total_ns += loop_ns; /* Re-calibrate. */ @@ -1628,10 +1628,15 @@ accuracy(int gem_fd, const struct intel_execution_engine2 *e, var += (err - avg) * (err - tmp); } while (pass_ns < timeout[pass]); + pass_ns = igt_nsec_elapsed(&start); expected = (double)busy_ns / pass_ns; - igt_info("%u: busy %"PRIu64"us, idle %"PRIu64"us -> %.2f%% (target: %lu%%; average=%.2f, variance=%f)\n", - pass, busy_ns / 1000, idle_ns / 1000, - 100 * expected, target_busy_pct, avg, var / n); + + igt_info("%u: %d cycles, busy %"PRIu64"us, idle %"PRIu64"us -> %.2f%% (target: %lu%%; average=%.2f±%.3f%%)\n", + pass, n, + busy_ns / 1000, (pass_ns - busy_ns) / 1000, + 100 * expected, target_busy_pct, + avg, sqrt(var / n)); + write(link[1], &expected, sizeof(expected)); } |