[igt-dev] [PATCH i-g-t] i915/i915_power: Measure GPU idle/busy power

Ashutosh Dixit
2023-01-17T19:03:26Z

In several instances (e.g. when investigating GPU power limits) it is very
useful to be able to measure GPU power easily. Since we already have all
ingredients for doing so, add a couple of tests to measure GPU power when
idle and power under load.

Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
---
tests/i915/i915_power.c | 60 +++++++++++++++++++++++++++++++++++++++++
tests/meson.build | 1 +
2 files changed, 61 insertions(+)
create mode 100644 tests/i915/i915_power.c

diff --git a/tests/i915/i915_power.c b/tests/i915/i915_power.c
new file mode 100644
index 00000000000..74c5a4ba4af
--- /dev/null
+++ b/tests/i915/i915_power.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+#include "igt.h"
+#include "i915/gem.h"
+#include "igt_power.h"
+
+IGT_TEST_DESCRIPTION("i915 power measurement/tests");
+
+static void measure_power(int i915, const char *domain, bool load)
+{
+ const intel_ctx_t *ctx = intel_ctx_create_all_physical(i915);
+ struct power_sample sample[2];
+ int sleep_duration_sec = 3;
+ struct igt_power pwr;
+ igt_spin_t *spin;
+
+ gem_quiescent_gpu(i915);
+ if (load) {
+ spin = igt_spin_new(i915, .ctx = ctx, .engine = ALL_ENGINES,
+ .flags = IGT_SPIN_POLL_RUN);
+ /* Wait till at least one spinner starts */
+ igt_spin_busywait_until_started(spin);
+ }
+
+ igt_require(!igt_power_open(i915, &pwr, domain));
+ igt_power_get_energy(&pwr, &sample[0]);
+ usleep(sleep_duration_sec * USEC_PER_SEC);
+ igt_power_get_energy(&pwr, &sample[1]);
+ igt_info("Measured power: %g mW\n", igt_power_get_mW(&pwr, &sample[0], &sample[1]));
+
+ igt_power_close(&pwr);
+ igt_free_spins(i915);
+ intel_ctx_destroy(i915, ctx);
+}
+
+igt_main
+{
+ int i915;
+
+ igt_fixture {
+ i915 = drm_open_driver_master(DRIVER_INTEL);
+ }
+
+ igt_describe("Measure idle gpu power");
+ igt_subtest("gpu-idle") {
+ measure_power(i915, "gpu", false);
+ }
+
+ igt_describe("Measure gpu power with load");
+ igt_subtest("gpu-busy") {
+ measure_power(i915, "gpu", true);
+ }
+
+ igt_fixture {
+ close(i915);
+ }
+}
diff --git a/tests/meson.build b/tests/meson.build
index e20a864035b..e0f41e9e6a1 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -212,6 +212,7 @@ i915_progs = [
'i915_pm_dc',
'i915_pm_rps',
'i915_pm_sseu',
+ 'i915_power',
'i915_query',
'i915_selftest',
'i915_suspend',
--
2.38.0