[igt-dev] [PATCH igt 2/3] igt/gem_exec_fence: Exercise merging fences

[Antonio Argenziano]

On 13/03/18 05:31, Chris Wilson wrote:
> Execute the same batch on each engine and check that the composite fence
> across all engines completes only after the batch is completed on every
> engine.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   tests/gem_exec_fence.c | 127 +++++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 127 insertions(+)
> 
> diff --git a/tests/gem_exec_fence.c b/tests/gem_exec_fence.c
> index 26bde788..95fc65e5 100644
> --- a/tests/gem_exec_fence.c
> +++ b/tests/gem_exec_fence.c
> @@ -208,6 +208,113 @@ static void test_fence_busy(int fd, unsigned ring, unsigned flags)
>   	gem_quiescent_gpu(fd);
>   }
>   
> +static void test_fence_busy_all(int fd, unsigned flags)
> +{
> +	const int gen = intel_gen(intel_get_drm_devid(fd));
> +	struct drm_i915_gem_exec_object2 obj;
> +	struct drm_i915_gem_relocation_entry reloc;
> +	struct drm_i915_gem_execbuffer2 execbuf;
> +	struct timespec tv;
> +	uint32_t *batch;
> +	unsigned int engine;
> +	int all, i, timeout;
> +
> +	gem_quiescent_gpu(fd);
> +
> +	memset(&execbuf, 0, sizeof(execbuf));
> +	execbuf.buffers_ptr = to_user_pointer(&obj);
> +	execbuf.buffer_count = 1;
> +
> +	memset(&obj, 0, sizeof(obj));
> +	obj.handle = gem_create(fd, 4096);
> +
> +	obj.relocs_ptr = to_user_pointer(&reloc);
> +	obj.relocation_count = 1;
> +	memset(&reloc, 0, sizeof(reloc));
> +
> +	batch = gem_mmap__wc(fd, obj.handle, 0, 4096, PROT_WRITE);
> +	gem_set_domain(fd, obj.handle,
> +		       I915_GEM_DOMAIN_GTT, I915_GEM_DOMAIN_GTT);
> +
> +	reloc.target_handle = obj.handle; /* recurse */
> +	reloc.presumed_offset = 0;
> +	reloc.offset = sizeof(uint32_t);
> +	reloc.delta = 0;
> +	reloc.read_domains = I915_GEM_DOMAIN_COMMAND;
> +	reloc.write_domain = 0;
> +
> +	i = 0;
> +	batch[i] = MI_BATCH_BUFFER_START;
> +	if (gen >= 8) {
> +		batch[i] |= 1 << 8 | 1;
> +		batch[++i] = 0;
> +		batch[++i] = 0;
> +	} else if (gen >= 6) {
> +		batch[i] |= 1 << 8;
> +		batch[++i] = 0;
> +	} else {
> +		batch[i] |= 2 << 6;
> +		batch[++i] = 0;
> +		if (gen < 4) {
> +			batch[i] |= 1;
> +			reloc.delta = 1;
> +		}
> +	}
> +	i++;
> +
> +	all = -1;
> +	for_each_engine(fd, engine) {

for_each_physical_engines to avoid submitting twice to the same engine.

Other than that it LGTM.

Reviewed-by: Antonio Argenziano <antonio.argenziano at intel.com>

> +		int fence, new;
> +
> +		execbuf.flags = engine | LOCAL_EXEC_FENCE_OUT;
> +		execbuf.rsvd2 = -1;
> +		gem_execbuf_wr(fd, &execbuf);
> +		fence = execbuf.rsvd2 >> 32;
> +		igt_assert(fence != -1);
> +
> +		if (all < 0) {
> +			all = fence;
> +			break;
> +		}
> +
> +		new = sync_fence_merge(all, fence);
> +		igt_assert_lte(0, new);
> +		close(all);
> +		close(fence);
> +
> +		all = new;
> +	}
> +
> +	igt_assert(gem_bo_busy(fd, obj.handle));
> +	igt_assert(fence_busy(all));
> +
> +	timeout = 120;
> +	if ((flags & HANG) == 0) {
> +		*batch = MI_BATCH_BUFFER_END;
> +		__sync_synchronize();
> +		timeout = 1;
> +	}
> +	munmap(batch, 4096);
> +
> +	if (flags & WAIT) {
> +		struct pollfd pfd = { .fd = all, .events = POLLIN };
> +		igt_assert(poll(&pfd, 1, timeout*1000) == 1);
> +	} else {
> +		memset(&tv, 0, sizeof(tv));
> +		while (fence_busy(all))
> +			igt_assert(igt_seconds_elapsed(&tv) < timeout);
> +	}
> +
> +	igt_assert(!gem_bo_busy(fd, obj.handle));
> +	igt_assert_eq(sync_fence_status(all),
> +		      flags & HANG ? -EIO : SYNC_FENCE_OK);
> +
> +	close(all);
> +	gem_close(fd, obj.handle);
> +
> +	gem_quiescent_gpu(fd);
> +}
> +
>   static void test_fence_await(int fd, unsigned ring, unsigned flags)
>   {
>   	const int gen = intel_gen(intel_get_drm_devid(fd));
> @@ -1465,6 +1572,26 @@ igt_main
>   		gem_submission_print_method(i915);
>   	}
>   
> +	igt_subtest_group {
> +		igt_fixture {
> +			igt_fork_hang_detector(i915);
> +		}
> +
> +		igt_subtest("basic-busy-all")
> +			test_fence_busy_all(i915, 0);
> +		igt_subtest("basic-wait-all")
> +			test_fence_busy_all(i915, WAIT);
> +
> +		igt_fixture {
> +			igt_stop_hang_detector();
> +		}
> +
> +		igt_subtest("busy-hang-all")
> +			test_fence_busy_all(i915, HANG);
> +		igt_subtest("wait-hang-all")
> +			test_fence_busy_all(i915, WAIT | HANG);
> +	}
> +
>   	for (e = intel_execution_engines; e->name; e++) {
>   		igt_subtest_group {
>   			igt_fixture {
>