Re: [RFC] drm/i915: Support replaying GPU hangs with captured context image
On 20/02/2024 22:50, Rodrigo Vivi wrote:
On Tue, Feb 13, 2024 at 01:14:34PM +, Tvrtko Ursulin wrote:
From: Tvrtko Ursulin
When debugging GPU hangs Mesa developers are finding it useful to replay
the captured error state against the simulator. But due various simulator
limitations which prevent replicating all hangs, one step further is being
able to replay against a real GPU.
This is almost doable today with the missing part being able to upload the
captured context image into the driver state prior to executing the
uploaded hanging batch and all the buffers.
To enable this last part we add a new context parameter called
I915_CONTEXT_PARAM_CONTEXT_IMAGE. It follows the existing SSEU
configuration pattern of being able to select which context to apply
against, paired with the actual image and its size.
Since this is adding a new concept of debug only uapi, we hide it behind
a new kconfig option and also require activation with a module parameter.
Together with a warning banner printed at driver load, all those combined
should be sufficient to guard against inadvertently enabling the feature.
In terms of implementation the only trivial change is shadowing of the
default state from engine to context. We also allow the legacy context
set param to be used since that removes the need to record the per context
data in the proto context, while still allowing flexibility of specifying
context images for any context.
Mesa MR using the uapi can be seen at:
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27594
I just wonder if it would be better to split the default_state in a separate
patch but from what I could see it looks correct.
It definitely makes sense to split it. I was just a bit lazy while
testing the waters. After all this is a very novel idea of debug only
uapi outside debugfs so I wasn't too sure how it will be received. Stay
tuned for v2.
Regards,
Tvrtko
Also, I have to say that this approach is nice, clean and well protected.
And much simpler then I imagined when I saw the idea around.
Feel free to use:
Reviewed-by: Rodrigo Vivi
Signed-off-by: Tvrtko Ursulin
Cc: Lionel Landwerlin
Cc: Carlos Santa
---
drivers/gpu/drm/i915/Kconfig.debug| 17 +++
drivers/gpu/drm/i915/gem/i915_gem_context.c | 106 ++
drivers/gpu/drm/i915/gt/intel_context.c | 2 +
drivers/gpu/drm/i915/gt/intel_context.h | 22
drivers/gpu/drm/i915/gt/intel_context_types.h | 3 +
drivers/gpu/drm/i915/gt/intel_lrc.c | 8 +-
.../gpu/drm/i915/gt/intel_ring_submission.c | 8 +-
drivers/gpu/drm/i915/i915_params.c| 5 +
drivers/gpu/drm/i915/i915_params.h| 3 +-
include/uapi/drm/i915_drm.h | 27 +
10 files changed, 194 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/i915/Kconfig.debug
b/drivers/gpu/drm/i915/Kconfig.debug
index 5b7162076850..32e9f70e91ed 100644
--- a/drivers/gpu/drm/i915/Kconfig.debug
+++ b/drivers/gpu/drm/i915/Kconfig.debug
@@ -16,6 +16,23 @@ config DRM_I915_WERROR
If in doubt, say "N".
+config DRM_I915_REPLAY_GPU_HANGS_API
+ bool "Enable GPU hang replay userspace API"
+ depends on DRM_I915
+ depends on EXPERT
+ default n
+ help
+ Choose this option if you want to enable special and unstable
+ userspace API used for replaying GPU hangs on a running system.
+
+ This API is intended to be used by userspace graphics stack developers
+ and provides no stability guarantees.
+
+ The API needs to be activated at boot time using the
+ enable_debug_only_api module parameter.
+
+ If in doubt, say "N".
+
config DRM_I915_DEBUG
bool "Enable additional driver debugging"
depends on DRM_I915
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c
b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index dcbfe32fd30c..1cfd624bd978 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -78,6 +78,7 @@
#include "gt/intel_engine_user.h"
#include "gt/intel_gpu_commands.h"
#include "gt/intel_ring.h"
+#include "gt/shmem_utils.h"
#include "pxp/intel_pxp.h"
@@ -949,6 +950,7 @@ static int set_proto_ctx_param(struct drm_i915_file_private *fpriv,
case I915_CONTEXT_PARAM_NO_ZEROMAP:
case I915_CONTEXT_PARAM_BAN_PERIOD:
case I915_CONTEXT_PARAM_RINGSIZE:
+ case I915_CONTEXT_PARAM_CONTEXT_IMAGE:
default:
ret = -EINVAL;
break;
@@ -2092,6 +2094,88 @@ static int get_protected(struct i915_gem_context *ctx,
return 0;
}
+static int set_context_image(struct i915_gem_context *ctx,
+struct drm_i915_gem_context_param *args)
+{
+ struct i915_gem_context_param_context_image user;
+ struct intel_context *ce;
+ struct file *shmem_state;
+ unsigned long lookup;
+
Re: [RFC] drm/i915: Support replaying GPU hangs with captured context image
On Tue, Feb 13, 2024 at 01:14:34PM +, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin
>
> When debugging GPU hangs Mesa developers are finding it useful to replay
> the captured error state against the simulator. But due various simulator
> limitations which prevent replicating all hangs, one step further is being
> able to replay against a real GPU.
>
> This is almost doable today with the missing part being able to upload the
> captured context image into the driver state prior to executing the
> uploaded hanging batch and all the buffers.
>
> To enable this last part we add a new context parameter called
> I915_CONTEXT_PARAM_CONTEXT_IMAGE. It follows the existing SSEU
> configuration pattern of being able to select which context to apply
> against, paired with the actual image and its size.
>
> Since this is adding a new concept of debug only uapi, we hide it behind
> a new kconfig option and also require activation with a module parameter.
> Together with a warning banner printed at driver load, all those combined
> should be sufficient to guard against inadvertently enabling the feature.
>
> In terms of implementation the only trivial change is shadowing of the
> default state from engine to context. We also allow the legacy context
> set param to be used since that removes the need to record the per context
> data in the proto context, while still allowing flexibility of specifying
> context images for any context.
>
> Mesa MR using the uapi can be seen at:
> https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27594
I just wonder if it would be better to split the default_state in a separate
patch but from what I could see it looks correct.
Also, I have to say that this approach is nice, clean and well protected.
And much simpler then I imagined when I saw the idea around.
Feel free to use:
Reviewed-by: Rodrigo Vivi
>
> Signed-off-by: Tvrtko Ursulin
> Cc: Lionel Landwerlin
> Cc: Carlos Santa
> ---
> drivers/gpu/drm/i915/Kconfig.debug| 17 +++
> drivers/gpu/drm/i915/gem/i915_gem_context.c | 106 ++
> drivers/gpu/drm/i915/gt/intel_context.c | 2 +
> drivers/gpu/drm/i915/gt/intel_context.h | 22
> drivers/gpu/drm/i915/gt/intel_context_types.h | 3 +
> drivers/gpu/drm/i915/gt/intel_lrc.c | 8 +-
> .../gpu/drm/i915/gt/intel_ring_submission.c | 8 +-
> drivers/gpu/drm/i915/i915_params.c| 5 +
> drivers/gpu/drm/i915/i915_params.h| 3 +-
> include/uapi/drm/i915_drm.h | 27 +
> 10 files changed, 194 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/Kconfig.debug
> b/drivers/gpu/drm/i915/Kconfig.debug
> index 5b7162076850..32e9f70e91ed 100644
> --- a/drivers/gpu/drm/i915/Kconfig.debug
> +++ b/drivers/gpu/drm/i915/Kconfig.debug
> @@ -16,6 +16,23 @@ config DRM_I915_WERROR
>
> If in doubt, say "N".
>
> +config DRM_I915_REPLAY_GPU_HANGS_API
> + bool "Enable GPU hang replay userspace API"
> + depends on DRM_I915
> + depends on EXPERT
> + default n
> + help
> + Choose this option if you want to enable special and unstable
> + userspace API used for replaying GPU hangs on a running system.
> +
> + This API is intended to be used by userspace graphics stack developers
> + and provides no stability guarantees.
> +
> + The API needs to be activated at boot time using the
> + enable_debug_only_api module parameter.
> +
> + If in doubt, say "N".
> +
> config DRM_I915_DEBUG
> bool "Enable additional driver debugging"
> depends on DRM_I915
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c
> b/drivers/gpu/drm/i915/gem/i915_gem_context.c
> index dcbfe32fd30c..1cfd624bd978 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
> @@ -78,6 +78,7 @@
> #include "gt/intel_engine_user.h"
> #include "gt/intel_gpu_commands.h"
> #include "gt/intel_ring.h"
> +#include "gt/shmem_utils.h"
>
> #include "pxp/intel_pxp.h"
>
> @@ -949,6 +950,7 @@ static int set_proto_ctx_param(struct
> drm_i915_file_private *fpriv,
> case I915_CONTEXT_PARAM_NO_ZEROMAP:
> case I915_CONTEXT_PARAM_BAN_PERIOD:
> case I915_CONTEXT_PARAM_RINGSIZE:
> + case I915_CONTEXT_PARAM_CONTEXT_IMAGE:
> default:
> ret = -EINVAL;
> break;
> @@ -2092,6 +2094,88 @@ static int get_protected(struct i915_gem_context *ctx,
> return 0;
> }
>
> +static int set_context_image(struct i915_gem_context *ctx,
> + struct drm_i915_gem_context_param *args)
> +{
> + struct i915_gem_context_param_context_image user;
> + struct intel_context *ce;
> + struct file *shmem_state;
> + unsigned long lookup;
> + void *state;
> + int ret = 0;
> +
> + if (!IS_ENABLED(CONFIG_DRM_I915_REPLAY_GPU_HANGS_API))
> + return -EINVAL;
> +
> + if
[RFC] drm/i915: Support replaying GPU hangs with captured context image
From: Tvrtko Ursulin
When debugging GPU hangs Mesa developers are finding it useful to replay
the captured error state against the simulator. But due various simulator
limitations which prevent replicating all hangs, one step further is being
able to replay against a real GPU.
This is almost doable today with the missing part being able to upload the
captured context image into the driver state prior to executing the
uploaded hanging batch and all the buffers.
To enable this last part we add a new context parameter called
I915_CONTEXT_PARAM_CONTEXT_IMAGE. It follows the existing SSEU
configuration pattern of being able to select which context to apply
against, paired with the actual image and its size.
Since this is adding a new concept of debug only uapi, we hide it behind
a new kconfig option and also require activation with a module parameter.
Together with a warning banner printed at driver load, all those combined
should be sufficient to guard against inadvertently enabling the feature.
In terms of implementation the only trivial change is shadowing of the
default state from engine to context. We also allow the legacy context
set param to be used since that removes the need to record the per context
data in the proto context, while still allowing flexibility of specifying
context images for any context.
Mesa MR using the uapi can be seen at:
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27594
Signed-off-by: Tvrtko Ursulin
Cc: Lionel Landwerlin
Cc: Carlos Santa
---
drivers/gpu/drm/i915/Kconfig.debug| 17 +++
drivers/gpu/drm/i915/gem/i915_gem_context.c | 106 ++
drivers/gpu/drm/i915/gt/intel_context.c | 2 +
drivers/gpu/drm/i915/gt/intel_context.h | 22
drivers/gpu/drm/i915/gt/intel_context_types.h | 3 +
drivers/gpu/drm/i915/gt/intel_lrc.c | 8 +-
.../gpu/drm/i915/gt/intel_ring_submission.c | 8 +-
drivers/gpu/drm/i915/i915_params.c| 5 +
drivers/gpu/drm/i915/i915_params.h| 3 +-
include/uapi/drm/i915_drm.h | 27 +
10 files changed, 194 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/i915/Kconfig.debug
b/drivers/gpu/drm/i915/Kconfig.debug
index 5b7162076850..32e9f70e91ed 100644
--- a/drivers/gpu/drm/i915/Kconfig.debug
+++ b/drivers/gpu/drm/i915/Kconfig.debug
@@ -16,6 +16,23 @@ config DRM_I915_WERROR
If in doubt, say "N".
+config DRM_I915_REPLAY_GPU_HANGS_API
+ bool "Enable GPU hang replay userspace API"
+ depends on DRM_I915
+ depends on EXPERT
+ default n
+ help
+ Choose this option if you want to enable special and unstable
+ userspace API used for replaying GPU hangs on a running system.
+
+ This API is intended to be used by userspace graphics stack developers
+ and provides no stability guarantees.
+
+ The API needs to be activated at boot time using the
+ enable_debug_only_api module parameter.
+
+ If in doubt, say "N".
+
config DRM_I915_DEBUG
bool "Enable additional driver debugging"
depends on DRM_I915
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c
b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index dcbfe32fd30c..1cfd624bd978 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -78,6 +78,7 @@
#include "gt/intel_engine_user.h"
#include "gt/intel_gpu_commands.h"
#include "gt/intel_ring.h"
+#include "gt/shmem_utils.h"
#include "pxp/intel_pxp.h"
@@ -949,6 +950,7 @@ static int set_proto_ctx_param(struct drm_i915_file_private
*fpriv,
case I915_CONTEXT_PARAM_NO_ZEROMAP:
case I915_CONTEXT_PARAM_BAN_PERIOD:
case I915_CONTEXT_PARAM_RINGSIZE:
+ case I915_CONTEXT_PARAM_CONTEXT_IMAGE:
default:
ret = -EINVAL;
break;
@@ -2092,6 +2094,88 @@ static int get_protected(struct i915_gem_context *ctx,
return 0;
}
+static int set_context_image(struct i915_gem_context *ctx,
+struct drm_i915_gem_context_param *args)
+{
+ struct i915_gem_context_param_context_image user;
+ struct intel_context *ce;
+ struct file *shmem_state;
+ unsigned long lookup;
+ void *state;
+ int ret = 0;
+
+ if (!IS_ENABLED(CONFIG_DRM_I915_REPLAY_GPU_HANGS_API))
+ return -EINVAL;
+
+ if (!ctx->i915->params.enable_debug_only_api)
+ return -EINVAL;
+
+ if (args->size < sizeof(user))
+ return -EINVAL;
+
+ if (copy_from_user(, u64_to_user_ptr(args->value), sizeof(user)))
+ return -EFAULT;
+
+ if (user.mbz)
+ return -EINVAL;
+
+ if (user.flags & ~(I915_CONTEXT_IMAGE_FLAG_ENGINE_INDEX))
+ return -EINVAL;
+
+ lookup = 0;
+ if (user.flags & I915_CONTEXT_IMAGE_FLAG_ENGINE_INDEX)
+ lookup |= LOOKUP_USER_INDEX;
+
+ ce
