[igt-dev] [PATCH i-g-t 07/11] tests/i915/i915_hangman: Add alive-ness test after error capture

[Zbigniew Kempczyński]

On Mon, Dec 13, 2021 at 03:29:10PM -0800, John.C.Harrison at Intel.com wrote:
> From: John Harrison <John.C.Harrison at Intel.com>
> 
> Added a an extra step to the i915_hangman tests to check that the
> system is still alive after the hang and recovery. This submits a
> simple batch to each engine which does a write to memory and checks
> that the write occurred.
> 
> Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
> ---
>  tests/i915/i915_hangman.c | 115 ++++++++++++++++++++++++++++++++++++++
>  1 file changed, 115 insertions(+)
> 
> diff --git a/tests/i915/i915_hangman.c b/tests/i915/i915_hangman.c
> index b77705206..20653b479 100644
> --- a/tests/i915/i915_hangman.c
> +++ b/tests/i915/i915_hangman.c
> @@ -47,8 +47,113 @@
>  static int device = -1;
>  static int sysfs = -1;
>  
> +#define OFFSET_ALIVE	10
> +
>  IGT_TEST_DESCRIPTION("Tests for hang detection and recovery");
>  
> +/* Requires master for STORE_DWORD on gen4/5 */
> +static void store(int fd, const struct intel_execution_engine2 *e,
> +		  int fence, uint32_t target, unsigned offset_value)
> +{
> +	const int SCRATCH = 0;
> +	const int BATCH = 1;
> +	const int gen = intel_gen(intel_get_drm_devid(fd));
> +	struct drm_i915_gem_exec_object2 obj[2];
> +	struct drm_i915_gem_relocation_entry reloc;
> +	struct drm_i915_gem_execbuffer2 execbuf;
> +	uint32_t batch[16];
> +	int i;
> +
> +	memset(&execbuf, 0, sizeof(execbuf));
> +	execbuf.buffers_ptr = to_user_pointer(obj);
> +	execbuf.buffer_count = ARRAY_SIZE(obj);
> +	execbuf.flags = e->flags;
> +	if (fence != -1) {
> +		execbuf.flags |= I915_EXEC_FENCE_IN;
> +		execbuf.rsvd2 = fence;
> +	}
> +	if (gen < 6)
> +		execbuf.flags |= I915_EXEC_SECURE;
> +
> +	memset(obj, 0, sizeof(obj));
> +	obj[SCRATCH].handle = target;
> +
> +	obj[BATCH].handle = gem_create(fd, 4096);
> +	obj[BATCH].relocs_ptr = to_user_pointer(&reloc);
> +	obj[BATCH].relocation_count = 1;
> +	memset(&reloc, 0, sizeof(reloc));
> +
> +	i = 0;
> +	reloc.target_handle = obj[SCRATCH].handle;
> +	reloc.presumed_offset = -1;
> +	reloc.offset = sizeof(uint32_t) * (i + 1);
> +	reloc.delta = sizeof(uint32_t) * offset_value;
> +	reloc.read_domains = I915_GEM_DOMAIN_INSTRUCTION;
> +	reloc.write_domain = I915_GEM_DOMAIN_INSTRUCTION;
> +	batch[i] = MI_STORE_DWORD_IMM | (gen < 6 ? 1 << 22 : 0);
> +	if (gen >= 8) {
> +		batch[++i] = reloc.delta;
> +		batch[++i] = 0;
> +	} else if (gen >= 4) {
> +		batch[++i] = 0;
> +		batch[++i] = reloc.delta;
> +		reloc.offset += sizeof(uint32_t);
> +	} else {
> +		batch[i]--;
> +		batch[++i] = reloc.delta;
> +	}
> +	batch[++i] = offset_value;
> +	batch[++i] = MI_BATCH_BUFFER_END;
> +	gem_write(fd, obj[BATCH].handle, 0, batch, sizeof(batch));
> +	gem_execbuf(fd, &execbuf);
> +	gem_close(fd, obj[BATCH].handle);
> +}
> +
> +static void check_alive(void)
> +{
> +	const struct intel_execution_engine2 *engine;
> +	const intel_ctx_t *ctx;
> +	uint32_t scratch, *out;
> +	int fd, i = 0;
> +	uint64_t ahnd;
> +
> +	fd = drm_open_driver(DRIVER_INTEL);
> +	igt_require(gem_class_can_store_dword(fd, 0));
> +
> +	ctx = intel_ctx_create_all_physical(fd);
> +	ahnd = get_reloc_ahnd(fd, ctx->id);
> +	scratch = gem_create(fd, 4096);
> +	out = gem_mmap__wc(fd, scratch, 0, 4096, PROT_WRITE);
> +	gem_set_domain(fd, scratch,
> +			I915_GEM_DOMAIN_GTT, I915_GEM_DOMAIN_GTT);
> +
> +	for_each_physical_engine(fd, engine) {
> +		igt_assert_eq_u32(out[i + OFFSET_ALIVE], 0);
> +		i++;
> +	}
> +
> +	i = 0;
> +	for_each_ctx_engine(fd, ctx, engine) {
> +		if (!gem_class_can_store_dword(fd, engine->class))
> +			continue;
> +
> +		/* +OFFSET_ALIVE to ensure engine zero doesn't get a false negative */
> +		store(fd, engine, -1, scratch, i + OFFSET_ALIVE);

You need to pass ctx + ahnd to store() to add softpin path. Relocs
won't work above Tigerlake.

--
Zbigniew


> +		i++;
> +	}
> +
> +	gem_set_domain(fd, scratch, I915_GEM_DOMAIN_GTT, 0);
> +
> +	while (i--)
> +		igt_assert_eq_u32(out[i + OFFSET_ALIVE], i + OFFSET_ALIVE);
> +
> +	munmap(out, 4096);
> +	gem_close(fd, scratch);
> +	put_ahnd(ahnd);
> +	intel_ctx_destroy(fd, ctx);
> +	close(fd);
> +}
> +
>  static bool has_error_state(int dir)
>  {
>  	bool result;
> @@ -230,6 +335,8 @@ static void test_error_state_capture(const intel_ctx_t *ctx,
>  	check_error_state(e->name, offset, batch);
>  	munmap(batch, 4096);
>  	put_ahnd(ahnd);
> +
> +	check_alive();
>  }
>  
>  static void
> @@ -288,6 +395,8 @@ test_engine_hang(const intel_ctx_t *ctx,
>  		put_ahnd(ahndN);
>  	}
>  	put_ahnd(ahnd);
> +
> +	check_alive();
>  }
>  
>  static int hang_count;
> @@ -320,6 +429,8 @@ static void test_hang_detector(const intel_ctx_t *ctx,
>  
>  	/* Did it work? */
>  	igt_assert(hang_count == 1);
> +
> +	check_alive();
>  }
>  
>  /* This test covers the case where we end up in an uninitialised area of the
> @@ -355,6 +466,8 @@ static void hangcheck_unterminated(const intel_ctx_t *ctx)
>  		igt_force_gpu_reset(device);
>  		igt_assert_f(0, "unterminated batch did not trigger a hang!");
>  	}
> +
> +	check_alive();
>  }
>  
>  static void do_tests(const char *name, const char *prefix,
> @@ -432,6 +545,8 @@ igt_main
>  		igt_assert(sysfs != -1);
>  
>  		igt_require(has_error_state(sysfs));
> +
> +		gem_require_mmap_wc(device);
>  	}
>  
>  	igt_describe("Basic error capture");
> -- 
> 2.25.1
>