[07/10] drm/i915/bdw: collect semaphore error state

Commit Message

Rodrigo Vivi June 30, 2014, 4:53 p.m. UTC

From: Ben Widawsky <[e-mail]>

Since the semaphore information is in an object, just dump it, and let
the user parse it later.

NOTE: The page being used for the semaphores are incoherent with the
CPU. No matter what I do, I cannot figure out a way to read anything but
0s. Note that the semaphore waits are indeed working.

v2: Don't print signal, and wait (they should be the same). Instead,
print sync_seqno (Chris)

v3: Free the semaphore error object (Chris)

v4: Fix semaphore offset calculation during error state collection
(Ville)

v5: VCS2 rebase
Make semaphore object error capture coding style consistent (Ville)
Do the proper math for the signal offset (Ville)

v6: Fix small conflicts on rebase and s/ring_buffer/engine_cs (Rodrigo)

Reviewed-by: Rodrigo Vivi <[e-mail]>
Signed-off-by: Ben Widawsky <[e-mail]>
Signed-off-by: Rodrigo Vivi <[e-mail]>
---
 drivers/gpu/drm/i915/i915_drv.h       |  1 +
 drivers/gpu/drm/i915/i915_gpu_error.c | 51 ++++++++++++++++++++++++++++++++---
 2 files changed, 48 insertions(+), 4 deletions(-)

Comments

Lespiau, Damien July 14, 2014, 10:04 a.m. UTC | #1

On Mon, Jun 30, 2014 at 09:53:41AM -0700, Rodrigo Vivi wrote:
> +	for_each_ring(useless, dev_priv, i) {
> +		u16 signal_offset =
> +			(GEN8_SIGNAL_OFFSET(ring, i) & PAGE_MASK) / 4;
> +		u32 *tmp = error->semaphore_obj->pages[0];
> +
> +		ering->semaphore_mboxes[i] = tmp[signal_offset];
> +		ering->semaphore_seqno[i] = ring->semaphore.sync_seqno[i];
> +	}
> +}

This loops around all the rings, but semaphore_mboxes[] and
semaphore_seqno[] are of size (I915_NUM_RINGS - 1).

Ben Widawsky July 14, 2014, 6:22 p.m. UTC | #2

On Mon, Jul 14, 2014 at 11:04:22AM +0100, Damien Lespiau wrote:
> On Mon, Jun 30, 2014 at 09:53:41AM -0700, Rodrigo Vivi wrote:
> > +	for_each_ring(useless, dev_priv, i) {
> > +		u16 signal_offset =
> > +			(GEN8_SIGNAL_OFFSET(ring, i) & PAGE_MASK) / 4;
> > +		u32 *tmp = error->semaphore_obj->pages[0];
> > +
> > +		ering->semaphore_mboxes[i] = tmp[signal_offset];
> > +		ering->semaphore_seqno[i] = ring->semaphore.sync_seqno[i];
> > +	}
> > +}
> 
> This loops around all the rings, but semaphore_mboxes[] and
> semaphore_seqno[] are of size (I915_NUM_RINGS - 1).
> 
> -- 
> Damien

Dan Carpenter has already reported this to us. I was expecting a patch
from Rodrigo.

Patch

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 61e43fc..f50ae5d 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -324,6 +324,7 @@  struct drm_i915_error_state {
 	u64 fence[I915_MAX_NUM_FENCES];
 	struct intel_overlay_error_state *overlay;
 	struct intel_display_error_state *display;
+	struct drm_i915_error_object *semaphore_obj;
 
 	struct drm_i915_error_ring {
 		bool valid;
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 9d42b6a..45b6191 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -327,6 +327,7 @@  int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
 	struct drm_device *dev = error_priv->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct drm_i915_error_state *error = error_priv->error;
+	struct drm_i915_error_object *obj;
 	int i, j, offset, elt;
 	int max_hangcheck_score;
 
@@ -395,8 +396,6 @@  int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
 				    error->pinned_bo_count[0]);
 
 	for (i = 0; i < ARRAY_SIZE(error->ring); i++) {
-		struct drm_i915_error_object *obj;
-
 		obj = error->ring[i].batchbuffer;
 		if (obj) {
 			err_puts(m, dev_priv->ring[i].name);
@@ -459,6 +458,18 @@  int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
 		}
 	}
 
+	if ((obj = error->semaphore_obj)) {
+		err_printf(m, "Semaphore page = 0x%08x\n", obj->gtt_offset);
+		for (elt = 0; elt < PAGE_SIZE/16; elt += 4) {
+			err_printf(m, "[%04x] %08x %08x %08x %08x\n",
+				   elt * 4,
+				   obj->pages[0][elt],
+				   obj->pages[0][elt+1],
+				   obj->pages[0][elt+2],
+				   obj->pages[0][elt+3]);
+		}
+	}
+
 	if (error->overlay)
 		intel_overlay_print_error_state(m, error->overlay);
 
@@ -529,6 +540,7 @@  static void i915_error_state_free(struct kref *error_ref)
 		kfree(error->ring[i].requests);
 	}
 
+	i915_error_object_free(error->semaphore_obj);
 	kfree(error->active_bo);
 	kfree(error->overlay);
 	kfree(error->display);
@@ -747,6 +759,33 @@  static void i915_gem_record_fences(struct drm_device *dev,
 }
 
 
+static void gen8_record_semaphore_state(struct drm_i915_private *dev_priv,
+					struct drm_i915_error_state *error,
+					struct intel_engine_cs *ring,
+					struct drm_i915_error_ring *ering)
+{
+	struct intel_engine_cs *useless;
+	int i;
+
+	if (!i915_semaphore_is_enabled(dev_priv->dev))
+		return;
+
+	if (!error->semaphore_obj)
+		error->semaphore_obj =
+			i915_error_object_create(dev_priv,
+						 dev_priv->semaphore_obj,
+						 &dev_priv->gtt.base);
+
+	for_each_ring(useless, dev_priv, i) {
+		u16 signal_offset =
+			(GEN8_SIGNAL_OFFSET(ring, i) & PAGE_MASK) / 4;
+		u32 *tmp = error->semaphore_obj->pages[0];
+
+		ering->semaphore_mboxes[i] = tmp[signal_offset];
+		ering->semaphore_seqno[i] = ring->semaphore.sync_seqno[i];
+	}
+}
+
 static void gen6_record_semaphore_state(struct drm_i915_private *dev_priv,
 					struct intel_engine_cs *ring,
 					struct drm_i915_error_ring *ering)
@@ -764,6 +803,7 @@  static void gen6_record_semaphore_state(struct drm_i915_private *dev_priv,
 }
 
 static void i915_record_ring_state(struct drm_device *dev,
+				   struct drm_i915_error_state *error,
 				   struct intel_engine_cs *ring,
 				   struct drm_i915_error_ring *ering)
 {
@@ -772,7 +812,10 @@  static void i915_record_ring_state(struct drm_device *dev,
 	if (INTEL_INFO(dev)->gen >= 6) {
 		ering->rc_psmi = I915_READ(ring->mmio_base + 0x50);
 		ering->fault_reg = I915_READ(RING_FAULT_REG(ring));
-		gen6_record_semaphore_state(dev_priv, ring, ering);
+		if (INTEL_INFO(dev)->gen >= 8)
+			gen8_record_semaphore_state(dev_priv, error, ring, ering);
+		else
+			gen6_record_semaphore_state(dev_priv, ring, ering);
 	}
 
 	if (INTEL_INFO(dev)->gen >= 4) {
@@ -901,7 +944,7 @@  static void i915_gem_record_rings(struct drm_device *dev,
 
 		error->ring[i].valid = true;
 
-		i915_record_ring_state(dev, ring, &error->ring[i]);
+		i915_record_ring_state(dev, error, ring, &error->ring[i]);
 
 		request = i915_gem_find_active_request(ring);
 		if (request) {