diff mbox

[05/14] drm/i915: Handle log buffer flush interrupt event from GuC

Message ID 1467485491-17247-6-git-send-email-akash.goel@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

akash.goel@intel.com July 2, 2016, 6:51 p.m. UTC 
From: Sagar Arun Kamble <sagar.a.kamble@intel.com>

GuC ukernel sends an interrupt to Host to flush the log buffer
and expects Host to correspondingly update the read pointer
information in the state structure, once it has consumed the
log buffer contents by copying them to a file or buffer.
Even if Host couldn't copy the contents, it can still update the
read pointer so that logging state is not disturbed on GuC side.

v2:
- Use a dedicated workqueue for handling flush interrupt. (Tvrtko)
- Reduce the overall log buffer copying time by skipping the copy of
  crash buffer area for regular cases and copying only the state
  structure data in first page.

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c            | 13 +++++
 drivers/gpu/drm/i915/i915_guc_submission.c | 87 ++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_irq.c            |  6 ++-
 drivers/gpu/drm/i915/intel_guc.h           |  2 +
 4 files changed, 106 insertions(+), 2 deletions(-)

Comments

Chris Wilson July 3, 2016, 9:15 a.m. UTC | #1 
On Sun, Jul 03, 2016 at 12:21:22AM +0530, akash.goel@intel.com wrote:
> +static void guc_read_update_log_buffer(struct drm_device *dev, bool capture_all)
> +{
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct intel_guc *guc = &dev_priv->guc;
> +	struct guc_log_buffer_state *log_buffer_state;
> +	struct guc_log_buffer_state *log_buffer_copy_state;
> +	void *src_ptr, *dst_ptr;
> +	u32 num_pages_to_copy;
> +	int i;
> +
> +	if (!guc->log.obj)
> +		return;
> +
> +	num_pages_to_copy = guc->log.obj->base.size / PAGE_SIZE;
> +	/* Don't really need to copy crash buffer area in regular cases as there
> +	 * won't be any unread data there.
> +	 */
> +	if (!capture_all)
> +		num_pages_to_copy -= (GUC_LOG_CRASH_PAGES + 1);
> +
> +	log_buffer_state = src_ptr =
> +		kmap_atomic(i915_gem_object_get_page(guc->log.obj, 0));

So why not use i915_gem_object_pin_map() from the start?

That will cut down on the churn later.
-Chris
akash.goel@intel.com July 3, 2016, 12:21 p.m. UTC | #2 
On 7/3/2016 2:45 PM, Chris Wilson wrote:
> On Sun, Jul 03, 2016 at 12:21:22AM +0530, akash.goel@intel.com wrote:
>> +static void guc_read_update_log_buffer(struct drm_device *dev, bool capture_all)
>> +{
>> +	struct drm_i915_private *dev_priv = dev->dev_private;
>> +	struct intel_guc *guc = &dev_priv->guc;
>> +	struct guc_log_buffer_state *log_buffer_state;
>> +	struct guc_log_buffer_state *log_buffer_copy_state;
>> +	void *src_ptr, *dst_ptr;
>> +	u32 num_pages_to_copy;
>> +	int i;
>> +
>> +	if (!guc->log.obj)
>> +		return;
>> +
>> +	num_pages_to_copy = guc->log.obj->base.size / PAGE_SIZE;
>> +	/* Don't really need to copy crash buffer area in regular cases as there
>> +	 * won't be any unread data there.
>> +	 */
>> +	if (!capture_all)
>> +		num_pages_to_copy -= (GUC_LOG_CRASH_PAGES + 1);
>> +
>> +	log_buffer_state = src_ptr =
>> +		kmap_atomic(i915_gem_object_get_page(guc->log.obj, 0));
>
> So why not use i915_gem_object_pin_map() from the start?
>
> That will cut down on the churn later.

Fine, will reorder the series and squash the other patch 'drm/i915: Use 
uncached(WC) mapping for accessing the GuC log buffer' with this patch.

Best regards
Akash
> -Chris
>
akash.goel@intel.com July 3, 2016, 12:25 p.m. UTC | #3 
On 7/3/2016 5:51 PM, Goel, Akash wrote:
>
>
> On 7/3/2016 2:45 PM, Chris Wilson wrote:
>> On Sun, Jul 03, 2016 at 12:21:22AM +0530, akash.goel@intel.com wrote:
>>> +static void guc_read_update_log_buffer(struct drm_device *dev, bool
>>> capture_all)
>>> +{
>>> +    struct drm_i915_private *dev_priv = dev->dev_private;
>>> +    struct intel_guc *guc = &dev_priv->guc;
>>> +    struct guc_log_buffer_state *log_buffer_state;
>>> +    struct guc_log_buffer_state *log_buffer_copy_state;
>>> +    void *src_ptr, *dst_ptr;
>>> +    u32 num_pages_to_copy;
>>> +    int i;
>>> +
>>> +    if (!guc->log.obj)
>>> +        return;
>>> +
>>> +    num_pages_to_copy = guc->log.obj->base.size / PAGE_SIZE;
>>> +    /* Don't really need to copy crash buffer area in regular cases
>>> as there
>>> +     * won't be any unread data there.
>>> +     */
>>> +    if (!capture_all)
>>> +        num_pages_to_copy -= (GUC_LOG_CRASH_PAGES + 1);
>>> +
>>> +    log_buffer_state = src_ptr =
>>> +        kmap_atomic(i915_gem_object_get_page(guc->log.obj, 0));
>>
>> So why not use i915_gem_object_pin_map() from the start?
>>
>> That will cut down on the churn later.
>
> Fine, will reorder the series and squash the other patch 'drm/i915: Use
> uncached(WC) mapping for accessing the GuC log buffer' with this patch.
>
Sorry got confused, will use the i915_gem_object_pin_map() here instead 
of kmap and keep the WC mapping patch at the end of series only. Then 
will just have to modify the call to i915_gem_object_pin_map() to pass 
the WC flag.


> Best regards
> Akash
>> -Chris
>>
Chris Wilson July 3, 2016, 1:01 p.m. UTC | #4 
On Sun, Jul 03, 2016 at 05:51:35PM +0530, Goel, Akash wrote:
> 
> 
> On 7/3/2016 2:45 PM, Chris Wilson wrote:
> >On Sun, Jul 03, 2016 at 12:21:22AM +0530, akash.goel@intel.com wrote:
> >>+static void guc_read_update_log_buffer(struct drm_device *dev, bool capture_all)
> >>+{
> >>+	struct drm_i915_private *dev_priv = dev->dev_private;
> >>+	struct intel_guc *guc = &dev_priv->guc;
> >>+	struct guc_log_buffer_state *log_buffer_state;
> >>+	struct guc_log_buffer_state *log_buffer_copy_state;
> >>+	void *src_ptr, *dst_ptr;
> >>+	u32 num_pages_to_copy;
> >>+	int i;
> >>+
> >>+	if (!guc->log.obj)
> >>+		return;
> >>+
> >>+	num_pages_to_copy = guc->log.obj->base.size / PAGE_SIZE;
> >>+	/* Don't really need to copy crash buffer area in regular cases as there
> >>+	 * won't be any unread data there.
> >>+	 */
> >>+	if (!capture_all)
> >>+		num_pages_to_copy -= (GUC_LOG_CRASH_PAGES + 1);
> >>+
> >>+	log_buffer_state = src_ptr =
> >>+		kmap_atomic(i915_gem_object_get_page(guc->log.obj, 0));
> >
> >So why not use i915_gem_object_pin_map() from the start?
> >
> >That will cut down on the churn later.
> 
> Fine, will reorder the series and squash the other patch 'drm/i915:
> Use uncached(WC) mapping for accessing the GuC log buffer' with this
> patch.

I would keep the pin_map(false -> true) as a separate step so that it is
clearly documented (and reversible).
-Chris
Chris Wilson July 3, 2016, 1:01 p.m. UTC | #5 
On Sun, Jul 03, 2016 at 05:55:14PM +0530, Goel, Akash wrote:
> 
> 
> On 7/3/2016 5:51 PM, Goel, Akash wrote:
> >
> >
> >On 7/3/2016 2:45 PM, Chris Wilson wrote:
> >>On Sun, Jul 03, 2016 at 12:21:22AM +0530, akash.goel@intel.com wrote:
> >>>+static void guc_read_update_log_buffer(struct drm_device *dev, bool
> >>>capture_all)
> >>>+{
> >>>+    struct drm_i915_private *dev_priv = dev->dev_private;
> >>>+    struct intel_guc *guc = &dev_priv->guc;
> >>>+    struct guc_log_buffer_state *log_buffer_state;
> >>>+    struct guc_log_buffer_state *log_buffer_copy_state;
> >>>+    void *src_ptr, *dst_ptr;
> >>>+    u32 num_pages_to_copy;
> >>>+    int i;
> >>>+
> >>>+    if (!guc->log.obj)
> >>>+        return;
> >>>+
> >>>+    num_pages_to_copy = guc->log.obj->base.size / PAGE_SIZE;
> >>>+    /* Don't really need to copy crash buffer area in regular cases
> >>>as there
> >>>+     * won't be any unread data there.
> >>>+     */
> >>>+    if (!capture_all)
> >>>+        num_pages_to_copy -= (GUC_LOG_CRASH_PAGES + 1);
> >>>+
> >>>+    log_buffer_state = src_ptr =
> >>>+        kmap_atomic(i915_gem_object_get_page(guc->log.obj, 0));
> >>
> >>So why not use i915_gem_object_pin_map() from the start?
> >>
> >>That will cut down on the churn later.
> >
> >Fine, will reorder the series and squash the other patch 'drm/i915: Use
> >uncached(WC) mapping for accessing the GuC log buffer' with this patch.
> >
> Sorry got confused, will use the i915_gem_object_pin_map() here
> instead of kmap and keep the WC mapping patch at the end of series
> only. Then will just have to modify the call to
> i915_gem_object_pin_map() to pass the WC flag.

Yup.
-Chris
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index b98afbd..ec3721c 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1174,8 +1174,20 @@  static int i915_workqueues_init(struct drm_i915_private *dev_priv)
 	if (dev_priv->gpu_error.hangcheck_wq == NULL)
 		goto out_free_dp_wq;
 
+	if (HAS_GUC_SCHED(dev_priv)) {
+		/* Need a dedicated wq to process log buffer flush interrupts
+		 * from GuC without much delay so as to avoid any loss of logs.
+		 */
+		dev_priv->guc.log.wq =
+			alloc_ordered_workqueue("i915-guc_log", 0);
+		if (dev_priv->guc.log.wq == NULL)
+			goto out_free_hangcheck_wq;
+	}
+
 	return 0;
 
+out_free_hangcheck_wq:
+	destroy_workqueue(dev_priv->gpu_error.hangcheck_wq);
 out_free_dp_wq:
 	destroy_workqueue(dev_priv->hotplug.dp_wq);
 out_free_wq:
@@ -1188,6 +1200,7 @@  out_err:
 
 static void i915_workqueues_cleanup(struct drm_i915_private *dev_priv)
 {
+	destroy_workqueue(dev_priv->guc.log.wq);
 	destroy_workqueue(dev_priv->gpu_error.hangcheck_wq);
 	destroy_workqueue(dev_priv->hotplug.dp_wq);
 	destroy_workqueue(dev_priv->wq);
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index b441951..425226e 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -166,6 +166,15 @@  static int host2guc_sample_forcewake(struct intel_guc *guc,
 	return host2guc_action(guc, data, ARRAY_SIZE(data));
 }
 
+static int host2guc_logbuffer_flush_complete(struct intel_guc *guc)
+{
+	u32 data[1];
+
+	data[0] = HOST2GUC_ACTION_LOG_BUFFER_FILE_FLUSH_COMPLETE;
+
+	return host2guc_action(guc, data, 1);
+}
+
 /*
  * Initialise, update, or clear doorbell data shared with the GuC
  *
@@ -819,6 +828,75 @@  err:
 	return NULL;
 }
 
+static void* guc_get_write_buffer(struct intel_guc *guc)
+{
+	return NULL;
+}
+
+static void guc_read_update_log_buffer(struct drm_device *dev, bool capture_all)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_guc *guc = &dev_priv->guc;
+	struct guc_log_buffer_state *log_buffer_state;
+	struct guc_log_buffer_state *log_buffer_copy_state;
+	void *src_ptr, *dst_ptr;
+	u32 num_pages_to_copy;
+	int i;
+
+	if (!guc->log.obj)
+		return;
+
+	num_pages_to_copy = guc->log.obj->base.size / PAGE_SIZE;
+	/* Don't really need to copy crash buffer area in regular cases as there
+	 * won't be any unread data there.
+	 */
+	if (!capture_all)
+		num_pages_to_copy -= (GUC_LOG_CRASH_PAGES + 1);
+
+	log_buffer_state = src_ptr =
+		kmap_atomic(i915_gem_object_get_page(guc->log.obj, 0));
+
+	/* Get the pointer to local buffer to store the logs */
+	dst_ptr = log_buffer_copy_state = guc_get_write_buffer(guc);
+
+	for (i = 0; i < GUC_MAX_LOG_BUFFER; i++) {
+		if (log_buffer_copy_state) {
+			memcpy(log_buffer_copy_state, log_buffer_state,
+					sizeof(struct guc_log_buffer_state));
+
+			/* The write pointer could have been updated by the GuC
+			 * firmware, after sending the flush interrupt to Host,
+			 * for consistency set the write pointer value to same
+			 * value of sampled_write_ptr in the snapshot buffer.
+			 */
+			log_buffer_copy_state->write_ptr =
+				log_buffer_copy_state->sampled_write_ptr;
+
+			log_buffer_copy_state++;
+		}
+
+		/* FIXME: invalidate/flush for log buffer needed */
+
+		/* Update the read pointer in the shared log buffer */
+		log_buffer_state->read_ptr =
+			log_buffer_state->sampled_write_ptr;
+
+		/* Clear the 'flush to file' flag */
+		log_buffer_state->flush_to_file = 0;
+		log_buffer_state++;
+	}
+
+	kunmap_atomic(src_ptr);
+
+	/* Now copy the actual logs */
+	for (i=1; (i < num_pages_to_copy) && dst_ptr; i++) {
+		dst_ptr += PAGE_SIZE;
+		src_ptr = kmap_atomic(i915_gem_object_get_page(guc->log.obj, i));
+		memcpy(dst_ptr, src_ptr, PAGE_SIZE);
+		kunmap_atomic(src_ptr);
+	}
+}
+
 static void guc_create_log(struct intel_guc *guc)
 {
 	struct drm_i915_private *dev_priv = guc_to_i915(guc);
@@ -1078,3 +1156,12 @@  int intel_guc_resume(struct drm_device *dev)
 
 	return host2guc_action(guc, data, ARRAY_SIZE(data));
 }
+
+void i915_guc_capture_logs(struct drm_device *dev, bool capture_all)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	guc_read_update_log_buffer(dev, capture_all);
+
+	host2guc_logbuffer_flush_complete(&dev_priv->guc);
+}
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index aefe1a1..7b8894c1 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1255,7 +1255,8 @@  static void gen9_guc2host_events_work(struct work_struct *work)
 	msg = I915_READ(SOFT_SCRATCH(15));
 	if (msg & (GUC2HOST_MSG_CRASH_DUMP_POSTED |
 		   GUC2HOST_MSG_FLUSH_LOG_BUFFER)) {
-		/* TODO: Handle the events for which GuC interrupted host */
+		i915_guc_capture_logs(dev_priv->dev,
+			msg & GUC2HOST_MSG_CRASH_DUMP_POSTED);
 
 		/* Clear GuC to Host msg bits that are handled */
 		if (msg & GUC2HOST_MSG_FLUSH_LOG_BUFFER)
@@ -1739,7 +1740,8 @@  static void gen9_guc_irq_handler(struct drm_i915_private *dev_priv, u32 gt_iir)
 		spin_lock(&dev_priv->irq_lock);
 		if (dev_priv->guc.interrupts_enabled) {
 			/* Process all the GuC to Host events in bottom half. */
-			queue_work(dev_priv->wq, &dev_priv->guc.events_work);
+			queue_work(dev_priv->guc.log.wq,
+					&dev_priv->guc.events_work);
 		}
 		spin_unlock(&dev_priv->irq_lock);
 	}
diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
index 2663b41..71aab85 100644
--- a/drivers/gpu/drm/i915/intel_guc.h
+++ b/drivers/gpu/drm/i915/intel_guc.h
@@ -125,6 +125,7 @@  struct intel_guc_fw {
 struct intel_guc_log {
 	uint32_t flags;
 	struct drm_i915_gem_object *obj;
+	struct workqueue_struct *wq;
 };
 
 struct intel_guc {
@@ -171,5 +172,6 @@  int i915_guc_wq_check_space(struct drm_i915_gem_request *rq);
 int i915_guc_submit(struct drm_i915_gem_request *rq);
 void i915_guc_submission_disable(struct drm_i915_private *dev_priv);
 void i915_guc_submission_fini(struct drm_i915_private *dev_priv);
+void i915_guc_capture_logs(struct drm_device *dev, bool capture_all);
 
 #endif