Re: [igt-dev] [PATCH i-g-t 04/15] perf_pmu: Quiesce GPU if measuring idle busyness without spinner

["Dixit, Ashutosh" <ashutosh.dixit@intel.com>]

On Fri, 05 May 2023 17:55:17 -0700, Umesh Nerlige Ramappa wrote:
>
> The assumption in some tests is that the engines are not busy if no
> spinners are being run. This is not true in some cases where we see
> that the render is busy at the start of the test. Quiesce GPU to wait
> for such work to complete before checking for idle busyness.
>
> v2: Move gem_quiescent_gpu to beginning of test (Tvrtko)

Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>

>
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> ---
>  tests/i915/perf_pmu.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/tests/i915/perf_pmu.c b/tests/i915/perf_pmu.c
> index 0b1177785..6080c5fdc 100644
> --- a/tests/i915/perf_pmu.c
> +++ b/tests/i915/perf_pmu.c
> @@ -279,6 +279,7 @@ single(int gem_fd, const intel_ctx_t *ctx,
>	int fd;
>	uint64_t ahnd = get_reloc_ahnd(gem_fd, ctx->id);
>
> +	gem_quiescent_gpu(gem_fd);
>	fd = open_pmu(gem_fd, I915_PMU_ENGINE_BUSY(e->class, e->instance));
>
>	if (flags & TEST_BUSY)
> @@ -639,6 +640,7 @@ no_sema(int gem_fd, const intel_ctx_t *ctx,
>	int fd[2];
>	uint64_t ahnd = get_reloc_ahnd(gem_fd, ctx->id);
>
> +	gem_quiescent_gpu(gem_fd);
>	fd[0] = open_group(gem_fd, I915_PMU_ENGINE_SEMA(e->class, e->instance),
>			   -1);
>	fd[1] = open_group(gem_fd, I915_PMU_ENGINE_WAIT(e->class, e->instance),
> --
> 2.34.1
>