Re: [PATCH 2/2] drm/i915/guc: Look for a guilty context when an engine reset fails
On Tue, Nov 29, 2022 at 01:12:53PM -0800, john.c.harri...@intel.com wrote:
From: John Harrison
Engine resets are supposed to never happen. But in the case when one
does (due to unknwon reasons that normally come down to a missing
w/a), it is useful to get as much information out of the system as
possible. Given that the GuC effectively dies on such a situation, it
is not possible to get a guilty context notification back. So do a
manual search instead. Given that GuC is dead, this is safe because
GuC won't be changing the engine state asynchronously.
Signed-off-by: John Harrison
---
drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 15 ++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 0a42f1807f52c..c82730804a1c4 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -4751,11 +4751,24 @@ static void reset_fail_worker_func(struct work_struct
*w)
guc->submission_state.reset_fail_mask = 0;
spin_unlock_irqrestore(&guc->submission_state.lock, flags);
- if (likely(reset_fail_mask))
+ if (likely(reset_fail_mask)) {
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+
+ /*
+* GuC is toast at this point - it dead loops after sending the
failed
+* reset notification. So need to manually determine the guilty
context.
+* Note that it should be safe/reliable to do this here because
the GuC
+* is toast and will not be scheduling behind the KMD's back.
+*/
Is that defined by the kmd-GuC interface that following a failed reset notification, GuC
will always dead-loop OR not schedule anything (even on other engines) until KMD takes
some action? What action should KMD take?
Regards,
Umesh
+ for_each_engine_masked(engine, gt, reset_fail_mask, id)
+ intel_guc_find_hung_context(engine);
+
intel_gt_handle_error(gt, reset_fail_mask,
I915_ERROR_CAPTURE,
"GuC failed to reset engine mask=0x%x\n",
reset_fail_mask);
+ }
}
int intel_guc_engine_failure_process_msg(struct intel_guc *guc,
--
2.37.3
Re: [Intel-gfx] [PATCH 2/2] drm/i915/guc: Look for a guilty context when an engine reset fails
On 30/11/2022 21:04, John Harrison wrote:
On 11/30/2022 00:30, Tvrtko Ursulin wrote:
On 29/11/2022 21:12, john.c.harri...@intel.com wrote:
From: John Harrison
Engine resets are supposed to never happen. But in the case when one
Engine resets or engine reset failures? Hopefully the latter.
Oops. Yes, that was meant to say "engine resets are never supposed to
fail."
does (due to unknwon reasons that normally come down to a missing
unknwon -> unknown
w/a), it is useful to get as much information out of the system as
possible. Given that the GuC effectively dies on such a situation, it
is not possible to get a guilty context notification back. So do a
manual search instead. Given that GuC is dead, this is safe because
GuC won't be changing the engine state asynchronously.
Signed-off-by: John Harrison
---
drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 15 ++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 0a42f1807f52c..c82730804a1c4 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -4751,11 +4751,24 @@ static void reset_fail_worker_func(struct
work_struct *w)
guc->submission_state.reset_fail_mask = 0;
spin_unlock_irqrestore(&guc->submission_state.lock, flags);
- if (likely(reset_fail_mask))
+ if (likely(reset_fail_mask)) {
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+
+ /*
+ * GuC is toast at this point - it dead loops after sending
the failed
+ * reset notification. So need to manually determine the
guilty context.
+ * Note that it should be safe/reliable to do this here
because the GuC
+ * is toast and will not be scheduling behind the KMD's back.
+ */
+ for_each_engine_masked(engine, gt, reset_fail_mask, id)
+ intel_guc_find_hung_context(engine);
+
intel_gt_handle_error(gt, reset_fail_mask,
I915_ERROR_CAPTURE,
"GuC failed to reset engine mask=0x%x\n",
reset_fail_mask);
If GuC is defined by ABI contract to be dead, should the flow be
attempting to do a full GPU reset here, or maybe it happens somewhere
else as a consequence anyway? (In which case is the engine reset here
even needed?)
This is a full GT reset. i915 is not allowed to perform an engine reset
when using GuC submission. Those can only be done by GuC. So any forced
reset by i915 will be escalated to full GT internally.
Okay, I saw passing in of the engine mask and drew the wrong conclusion.
Regards,
Tvrtko
Re: [Intel-gfx] [PATCH 2/2] drm/i915/guc: Look for a guilty context when an engine reset fails
On 11/30/2022 00:30, Tvrtko Ursulin wrote:
On 29/11/2022 21:12, john.c.harri...@intel.com wrote:
From: John Harrison
Engine resets are supposed to never happen. But in the case when one
Engine resets or engine reset failures? Hopefully the latter.
Oops. Yes, that was meant to say "engine resets are never supposed to fail."
does (due to unknwon reasons that normally come down to a missing
unknwon -> unknown
w/a), it is useful to get as much information out of the system as
possible. Given that the GuC effectively dies on such a situation, it
is not possible to get a guilty context notification back. So do a
manual search instead. Given that GuC is dead, this is safe because
GuC won't be changing the engine state asynchronously.
Signed-off-by: John Harrison
---
drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 15 ++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 0a42f1807f52c..c82730804a1c4 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -4751,11 +4751,24 @@ static void reset_fail_worker_func(struct
work_struct *w)
guc->submission_state.reset_fail_mask = 0;
spin_unlock_irqrestore(&guc->submission_state.lock, flags);
- if (likely(reset_fail_mask))
+ if (likely(reset_fail_mask)) {
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+
+ /*
+ * GuC is toast at this point - it dead loops after sending
the failed
+ * reset notification. So need to manually determine the
guilty context.
+ * Note that it should be safe/reliable to do this here
because the GuC
+ * is toast and will not be scheduling behind the KMD's back.
+ */
+ for_each_engine_masked(engine, gt, reset_fail_mask, id)
+ intel_guc_find_hung_context(engine);
+
intel_gt_handle_error(gt, reset_fail_mask,
I915_ERROR_CAPTURE,
"GuC failed to reset engine mask=0x%x\n",
reset_fail_mask);
If GuC is defined by ABI contract to be dead, should the flow be
attempting to do a full GPU reset here, or maybe it happens somewhere
else as a consequence anyway? (In which case is the engine reset here
even needed?)
This is a full GT reset. i915 is not allowed to perform an engine reset
when using GuC submission. Those can only be done by GuC. So any forced
reset by i915 will be escalated to full GT internally.
John.
Regards,
Tvrtko
+ }
}
int intel_guc_engine_failure_process_msg(struct intel_guc *guc,
Re: [Intel-gfx] [PATCH 2/2] drm/i915/guc: Look for a guilty context when an engine reset fails
On 29/11/2022 21:12, john.c.harri...@intel.com wrote:
From: John Harrison
Engine resets are supposed to never happen. But in the case when one
Engine resets or engine reset failures? Hopefully the latter.
does (due to unknwon reasons that normally come down to a missing
w/a), it is useful to get as much information out of the system as
possible. Given that the GuC effectively dies on such a situation, it
is not possible to get a guilty context notification back. So do a
manual search instead. Given that GuC is dead, this is safe because
GuC won't be changing the engine state asynchronously.
Signed-off-by: John Harrison
---
drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 15 ++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 0a42f1807f52c..c82730804a1c4 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -4751,11 +4751,24 @@ static void reset_fail_worker_func(struct work_struct
*w)
guc->submission_state.reset_fail_mask = 0;
spin_unlock_irqrestore(&guc->submission_state.lock, flags);
- if (likely(reset_fail_mask))
+ if (likely(reset_fail_mask)) {
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+
+ /*
+* GuC is toast at this point - it dead loops after sending the
failed
+* reset notification. So need to manually determine the guilty
context.
+* Note that it should be safe/reliable to do this here because
the GuC
+* is toast and will not be scheduling behind the KMD's back.
+*/
+ for_each_engine_masked(engine, gt, reset_fail_mask, id)
+ intel_guc_find_hung_context(engine);
+
intel_gt_handle_error(gt, reset_fail_mask,
I915_ERROR_CAPTURE,
"GuC failed to reset engine mask=0x%x\n",
reset_fail_mask);
If GuC is defined by ABI contract to be dead, should the flow be
attempting to do a full GPU reset here, or maybe it happens somewhere
else as a consequence anyway? (In which case is the engine reset here
even needed?)
Regards,
Tvrtko
+ }
}
int intel_guc_engine_failure_process_msg(struct intel_guc *guc,
[PATCH 2/2] drm/i915/guc: Look for a guilty context when an engine reset fails
From: John Harrison
Engine resets are supposed to never happen. But in the case when one
does (due to unknwon reasons that normally come down to a missing
w/a), it is useful to get as much information out of the system as
possible. Given that the GuC effectively dies on such a situation, it
is not possible to get a guilty context notification back. So do a
manual search instead. Given that GuC is dead, this is safe because
GuC won't be changing the engine state asynchronously.
Signed-off-by: John Harrison
---
drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 15 ++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 0a42f1807f52c..c82730804a1c4 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -4751,11 +4751,24 @@ static void reset_fail_worker_func(struct work_struct
*w)
guc->submission_state.reset_fail_mask = 0;
spin_unlock_irqrestore(&guc->submission_state.lock, flags);
- if (likely(reset_fail_mask))
+ if (likely(reset_fail_mask)) {
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+
+ /*
+* GuC is toast at this point - it dead loops after sending the
failed
+* reset notification. So need to manually determine the guilty
context.
+* Note that it should be safe/reliable to do this here because
the GuC
+* is toast and will not be scheduling behind the KMD's back.
+*/
+ for_each_engine_masked(engine, gt, reset_fail_mask, id)
+ intel_guc_find_hung_context(engine);
+
intel_gt_handle_error(gt, reset_fail_mask,
I915_ERROR_CAPTURE,
"GuC failed to reset engine mask=0x%x\n",
reset_fail_mask);
+ }
}
int intel_guc_engine_failure_process_msg(struct intel_guc *guc,
--
2.37.3
