[igt-dev] [PATCH igt 3/5] igt/gem_ctx_switch: Exercise all engines at once

[Antonio Argenziano]

On 28/02/18 07:51, Chris Wilson wrote:
> Just a small variant to apply a continuous context-switch load to all
> engines.
> ---
>   tests/gem_ctx_switch.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 83 insertions(+)
> 
> diff --git a/tests/gem_ctx_switch.c b/tests/gem_ctx_switch.c
> index 79b1d74b..4c7c5391 100644
> --- a/tests/gem_ctx_switch.c
> +++ b/tests/gem_ctx_switch.c
> @@ -133,6 +133,84 @@ static void single(int fd, uint32_t handle,
>   		gem_context_destroy(fd, contexts[n]);
>   }
>   
> +static void all(int fd, uint32_t handle, unsigned flags, int timeout)
> +{
> +	struct drm_i915_gem_execbuffer2 execbuf;
> +	struct drm_i915_gem_exec_object2 obj[2];
> +	unsigned int engine[16], e;
> +	const char *name[16];
> +	uint32_t contexts[65];
> +	unsigned int nengine;
> +	int n;
> +
> +	nengine = 0;
> +	for_each_engine(fd, e) {
> +		if (e == 0 || e == I915_EXEC_BSD)
> +			continue;

for_each_physical_engine()?

> +
> +		engine[nengine] = e;
> +		name[nengine] = e__->name;
> +		nengine++;
> +	}
> +	igt_require(nengine);
> +
> +	igt_require(__gem_context_create(fd, &contexts[0]) == 0);

gem_require_contexts already in fixture.

Thanks,
Antonio

> +	for (n = 1; n < ARRAY_SIZE(contexts); n++)
> +		contexts[n] = gem_context_create(fd);
> +
> +	memset(obj, 0, sizeof(obj));
> +	obj[1].handle = handle;
> +
> +	memset(&execbuf, 0, sizeof(execbuf));
> +	execbuf.buffers_ptr = to_user_pointer(obj + 1);
> +	execbuf.buffer_count = 1;
> +	execbuf.rsvd1 = contexts[0];
> +	execbuf.flags |= LOCAL_I915_EXEC_HANDLE_LUT;
> +	execbuf.flags |= LOCAL_I915_EXEC_NO_RELOC;
> +	igt_require(__gem_execbuf(fd, &execbuf) == 0);
> +	gem_sync(fd, handle);
> +	execbuf.buffers_ptr = to_user_pointer(obj);
> +	execbuf.buffer_count = 2;
> +
> +	for (int pot = 2; pot <= 64; pot *= 2) {
> +		for (int nctx = pot - 1; nctx <= pot + 1; nctx++) {
> +			igt_fork(child, nengine) {
> +				struct timespec start, now;
> +				unsigned int count = 0;
> +
> +				obj[0].handle = gem_create(fd, 4096);
> +				execbuf.flags |= engine[child];
> +				for (int loop = 0; loop < ARRAY_SIZE(contexts); loop++) {
> +					execbuf.rsvd1 = contexts[loop];
> +					gem_execbuf(fd, &execbuf);
> +				}
> +				gem_sync(fd, obj[0].handle);
> +
> +				clock_gettime(CLOCK_MONOTONIC, &start);
> +				do {
> +					for (int loop = 0; loop < 1024; loop++) {
> +						execbuf.rsvd1 = contexts[loop % nctx];
> +						gem_execbuf(fd, &execbuf);
> +					}
> +					count += 1024;
> +					clock_gettime(CLOCK_MONOTONIC, &now);
> +				} while (elapsed(&start, &now) < timeout);
> +				gem_sync(fd, obj[0].handle);
> +				clock_gettime(CLOCK_MONOTONIC, &now);
> +				gem_close(fd, obj[0].handle);
> +
> +				igt_info("[%d:%d] %s: %'u cycles: %.3fus%s\n",
> +					 nctx, child, name[child], count, elapsed(&start, &now)*1e6 / count,
> +					 flags & INTERRUPTIBLE ? " (interruptible)" : "");
> +			}
> +			igt_waitchildren();
> +		}
> +	}
> +
> +	for (n = 0; n < ARRAY_SIZE(contexts); n++)
> +		gem_context_destroy(fd, contexts[n]);
> +}
> +
>   igt_main
>   {
>   	const int ncpus = sysconf(_SC_NPROCESSORS_ONLN);
> @@ -175,6 +253,11 @@ igt_main
>   			single(fd, light, e, INTERRUPTIBLE, ncpus, 150);
>   	}
>   
> +	igt_subtest("basic-all")
> +		all(fd, light, 0, 5);
> +	igt_subtest("basic-all-heavy")
> +		all(fd, heavy, 0, 20);
> +
>   	igt_fixture {
>   		igt_stop_hang_detector();
>   		gem_close(fd, heavy);
>