[igt-dev] [PATCH i-g-t 4/4] tests/gem_media_vme: Shut down half of subslices to avoid gpu hang on ICL

Tvrtko Ursulin
2019-01-08T15:13:03Z

From: Tony Ye <tony.ye@intel.com>

On Icelake we need to turn off subslices not containing the VME block or
the VME kernel will hang.

v2: (Tvrtko Ursulin)
* Remove libdrm usage for setting context param.
* Cleanup bitmask operation.
* Only apply the workaround for ICL.

v3: (Tvrtko Ursulin)
* Added hang detector. (Chris Wilson)

v4: (Tvrtko Ursulin)
* Rebase for hang detector moved to previous patch.
* Tidy curly braces.

v5: (Tvrtko Ursulin)
* Whitespace tidy. (Joonas)

Signed-off-by: Tony Ye <tony.ye@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Tony Ye <tony.ye@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
---
lib/gpu_cmds.c | 12 ++++++++
lib/gpu_cmds.h | 3 ++
lib/media_fill.c | 2 +-
tests/i915/gem_media_vme.c | 60 ++++++++++++++++++++++++++++++++++++++
4 files changed, 76 insertions(+), 1 deletion(-)

diff --git a/lib/gpu_cmds.c b/lib/gpu_cmds.c
index b490a63bdfef..8d270ee86229 100644
--- a/lib/gpu_cmds.c
+++ b/lib/gpu_cmds.c
@@ -36,6 +36,18 @@ gen7_render_flush(struct intel_batchbuffer *batch, uint32_t batch_end)
igt_assert(ret == 0);
}

+void
+gen7_render_context_flush(struct intel_batchbuffer *batch, uint32_t batch_end)
+{
+ int ret;
+
+ ret = drm_intel_bo_subdata(batch->bo, 0, 4096, batch->buffer);
+ if (ret == 0)
+ ret = drm_intel_gem_bo_context_exec(batch->bo, batch->ctx,
+ batch_end, 0);
+ igt_assert(ret == 0);
+}
+
uint32_t
gen7_fill_curbe_buffer_data(struct intel_batchbuffer *batch,
uint8_t color)
diff --git a/lib/gpu_cmds.h b/lib/gpu_cmds.h
index ca671fb52daf..1321af446161 100644
--- a/lib/gpu_cmds.h
+++ b/lib/gpu_cmds.h
@@ -40,6 +40,9 @@
void
gen7_render_flush(struct intel_batchbuffer *batch, uint32_t batch_end);

+void
+gen7_render_context_flush(struct intel_batchbuffer *batch, uint32_t batch_end);
+
uint32_t
gen7_fill_curbe_buffer_data(struct intel_batchbuffer *batch,
uint8_t color);
diff --git a/lib/media_fill.c b/lib/media_fill.c
index b1e84727394a..03b5e71e101b 100644
--- a/lib/media_fill.c
+++ b/lib/media_fill.c
@@ -338,7 +338,7 @@ __gen11_media_vme_func(struct intel_batchbuffer *batch,
batch_end = intel_batchbuffer_align(batch, 8);
assert(batch_end < BATCH_STATE_SPLIT);

- gen7_render_flush(batch, batch_end);
+ gen7_render_context_flush(batch, batch_end);
intel_batchbuffer_reset(batch);
}

diff --git a/tests/i915/gem_media_vme.c b/tests/i915/gem_media_vme.c
index 8d9fd822b2ee..d5045ad1d785 100644
--- a/tests/i915/gem_media_vme.c
+++ b/tests/i915/gem_media_vme.c
@@ -81,6 +81,52 @@ static void scratch_buf_init_dst(drm_intel_bufmgr *bufmgr, struct igt_buf *buf)
buf->stride = 1;
}

+static uint64_t switch_off_n_bits(uint64_t mask, unsigned int n)
+{
+ unsigned int i;
+
+ igt_assert(n > 0 && n <= (sizeof(mask) * 8));
+ igt_assert(n <= __builtin_popcount(mask));
+
+ for (i = 0; n && i < (sizeof(mask) * 8); i++) {
+ uint64_t bit = 1ULL << i;
+
+ if (bit & mask) {
+ mask &= ~bit;
+ n--;
+ }
+ }
+
+ return mask;
+}
+
+static void shut_non_vme_subslices(int drm_fd, uint32_t ctx)
+{
+ struct drm_i915_gem_context_param_sseu sseu = { };
+ struct drm_i915_gem_context_param arg = {
+ .param = I915_CONTEXT_PARAM_SSEU,
+ .ctx_id = ctx,
+ .size = sizeof(sseu),
+ .value = to_user_pointer(&sseu),
+ };
+ int ret;
+
+ if (__gem_context_get_param(drm_fd, &arg))
+ return; /* no sseu support */
+
+ ret = __gem_context_set_param(drm_fd, &arg);
+ igt_assert(ret == 0 || ret == -ENODEV || ret == -EINVAL);
+ if (ret)
+ return; /* no sseu support */
+
+ /* shutdown half subslices */
+ sseu.subslice_mask =
+ switch_off_n_bits(sseu.subslice_mask,
+ __builtin_popcount(sseu.subslice_mask) / 2);
+
+ gem_context_set_param(drm_fd, &arg);
+}
+
igt_simple_main
{
int drm_fd;
@@ -107,6 +153,20 @@ igt_simple_main
scratch_buf_init_src(bufmgr, &src);
scratch_buf_init_dst(bufmgr, &dst);

+ batch->ctx = drm_intel_gem_context_create(bufmgr);
+ igt_assert(batch->ctx);
+
+ /* ICL hangs if non-VME enabled slices are enabled with a VME kernel. */
+ if (intel_gen(devid) == 11) {
+ uint32_t ctx_id;
+ int ret;
+
+ ret = drm_intel_gem_context_get_id(batch->ctx, &ctx_id);
+ igt_assert_eq(ret, 0);
+
+ shut_non_vme_subslices(drm_fd, ctx_id);
+ }
+
igt_fork_hang_detector(drm_fd);

media_vme(batch, &src, WIDTH, HEIGHT, &dst);