diff mbox series

[1/1] drm/syncobj: add sideband payload

Message ID 20190917110343.32371-2-lionel.g.landwerlin@intel.com (mailing list archive)
State New, archived
Headers show
Series drm/syncobj: add sideband payload | expand

Commit Message

Lionel Landwerlin Sept. 17, 2019, 11:03 a.m. UTC
The Vulkan timeline semaphores allow signaling to happen on the point
of the timeline without all of the its dependencies to be created.

The current 2 implementations (AMD/Intel) of the Vulkan spec on top of
the Linux kernel are using a thread to wait on the dependencies of a
given point to materialize and delay actual submission to the kernel
driver until the wait completes.

If a binary semaphore is submitted for signaling along the side of a
timeline semaphore waiting for completion that means that the drm
syncobj associated with that binary semaphore will not have a DMA
fence associated with it by the time vkQueueSubmit() returns. This and
the fact that a binary semaphore can be signaled and unsignaled as
before its DMA fences materialize mean that we cannot just rely on the
fence within the syncobj but we also need a sideband payload verifying
that the fence in the syncobj matches the last submission from the
Vulkan API point of view.

This change adds a sideband payload that is incremented with signaled
syncobj when vkQueueSubmit() is called. The next vkQueueSubmit()
waiting on a the syncobj will read the sideband payload and wait for a
fence chain element with a seqno superior or equal to the sideband
payload value to be added into the fence chain and use that fence to
trigger the submission on the kernel driver.

v2: Use a separate ioctl to get/set the sideband value (Christian)

v3: Use 2 ioctls for get/set (Christian)

v4: Use a single new ioctl

v5: a bunch of blattant mistakes
    Store payload atomically (Chris)

v6: Only touch atomic value once (Jason)

v7: Updated atomic value when importing sync file

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: David Zhou <David1.Zhou@amd.com> (v6)
Cc: Christian Koenig <Christian.Koenig@amd.com>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: David(ChunMing) Zhou <David1.Zhou@amd.com>
---
 drivers/gpu/drm/drm_internal.h |  2 ++
 drivers/gpu/drm/drm_ioctl.c    |  3 ++
 drivers/gpu/drm/drm_syncobj.c  | 64 ++++++++++++++++++++++++++++++++--
 include/drm/drm_syncobj.h      |  9 +++++
 include/uapi/drm/drm.h         | 17 +++++++++
 5 files changed, 93 insertions(+), 2 deletions(-)

Comments

Chunming Zhou Sept. 17, 2019, 12:36 p.m. UTC | #1
Hi Lionel,
The update looks good to me.
I tried your signal-order test, seems it isn't ready to run, not sure if I can reproduce your this issue.

-David
Lionel Landwerlin Sept. 17, 2019, 1:06 p.m. UTC | #2
Thanks David,

I'll try to fix the test to match AMD's restrictions.

The v7 here was to fix another existing test : 
dEQP-VK.api.external.fence.sync_fd.transference_temporary

Cheers,

-Lionel

On 17/09/2019 15:36, Zhou, David(ChunMing) wrote:
> Hi Lionel,
> The update looks good to me.
> I tried your signal-order test, seems it isn't ready to run, not sure 
> if I can reproduce your this issue.
>
> -David
> ------------------------------------------------------------------------
> *From:* Lionel Landwerlin <lionel.g.landwerlin@intel.com>
> *Sent:* Tuesday, September 17, 2019 7:03 PM
> *To:* dri-devel@lists.freedesktop.org <dri-devel@lists.freedesktop.org>
> *Cc:* Lionel Landwerlin <lionel.g.landwerlin@intel.com>; Zhou, 
> David(ChunMing) <David1.Zhou@amd.com>; Koenig, Christian 
> <Christian.Koenig@amd.com>; Jason Ekstrand <jason@jlekstrand.net>
> *Subject:* [PATCH 1/1] drm/syncobj: add sideband payload
> The Vulkan timeline semaphores allow signaling to happen on the point
> of the timeline without all of the its dependencies to be created.
>
> The current 2 implementations (AMD/Intel) of the Vulkan spec on top of
> the Linux kernel are using a thread to wait on the dependencies of a
> given point to materialize and delay actual submission to the kernel
> driver until the wait completes.
>
> If a binary semaphore is submitted for signaling along the side of a
> timeline semaphore waiting for completion that means that the drm
> syncobj associated with that binary semaphore will not have a DMA
> fence associated with it by the time vkQueueSubmit() returns. This and
> the fact that a binary semaphore can be signaled and unsignaled as
> before its DMA fences materialize mean that we cannot just rely on the
> fence within the syncobj but we also need a sideband payload verifying
> that the fence in the syncobj matches the last submission from the
> Vulkan API point of view.
>
> This change adds a sideband payload that is incremented with signaled
> syncobj when vkQueueSubmit() is called. The next vkQueueSubmit()
> waiting on a the syncobj will read the sideband payload and wait for a
> fence chain element with a seqno superior or equal to the sideband
> payload value to be added into the fence chain and use that fence to
> trigger the submission on the kernel driver.
>
> v2: Use a separate ioctl to get/set the sideband value (Christian)
>
> v3: Use 2 ioctls for get/set (Christian)
>
> v4: Use a single new ioctl
>
> v5: a bunch of blattant mistakes
>     Store payload atomically (Chris)
>
> v6: Only touch atomic value once (Jason)
>
> v7: Updated atomic value when importing sync file
>
> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
> Reviewed-by: David Zhou <David1.Zhou@amd.com> (v6)
> Cc: Christian Koenig <Christian.Koenig@amd.com>
> Cc: Jason Ekstrand <jason@jlekstrand.net>
> Cc: David(ChunMing) Zhou <David1.Zhou@amd.com>
> ---
>  drivers/gpu/drm/drm_internal.h |  2 ++
>  drivers/gpu/drm/drm_ioctl.c    |  3 ++
>  drivers/gpu/drm/drm_syncobj.c  | 64 ++++++++++++++++++++++++++++++++--
>  include/drm/drm_syncobj.h      |  9 +++++
>  include/uapi/drm/drm.h         | 17 +++++++++
>  5 files changed, 93 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_internal.h 
> b/drivers/gpu/drm/drm_internal.h
> index 51a2055c8f18..e297dfd85019 100644
> --- a/drivers/gpu/drm/drm_internal.h
> +++ b/drivers/gpu/drm/drm_internal.h
> @@ -208,6 +208,8 @@ int drm_syncobj_timeline_signal_ioctl(struct 
> drm_device *dev, void *data,
>                                        struct drm_file *file_private);
>  int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
>                              struct drm_file *file_private);
> +int drm_syncobj_binary_ioctl(struct drm_device *dev, void *data,
> +                            struct drm_file *file_private);
>
>  /* drm_framebuffer.c */
>  void drm_framebuffer_print_info(struct drm_printer *p, unsigned int 
> indent,
> diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
> index f675a3bb2c88..644d0bc800a4 100644
> --- a/drivers/gpu/drm/drm_ioctl.c
> +++ b/drivers/gpu/drm/drm_ioctl.c
> @@ -703,6 +703,9 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
>                        DRM_RENDER_ALLOW),
>          DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
>                        DRM_RENDER_ALLOW),
> +       DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_BINARY, drm_syncobj_binary_ioctl,
> +                     DRM_RENDER_ALLOW),
> +
>          DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, 
> drm_crtc_get_sequence_ioctl, 0),
>          DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, 
> drm_crtc_queue_sequence_ioctl, 0),
>          DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, 
> drm_mode_create_lease_ioctl, DRM_MASTER),
> diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
> index 4b5c7b0ed714..2de8f1380890 100644
> --- a/drivers/gpu/drm/drm_syncobj.c
> +++ b/drivers/gpu/drm/drm_syncobj.c
> @@ -418,8 +418,10 @@ int drm_syncobj_create(struct drm_syncobj 
> **out_syncobj, uint32_t flags,
>          if (flags & DRM_SYNCOBJ_CREATE_SIGNALED)
>                  drm_syncobj_assign_null_handle(syncobj);
>
> -       if (fence)
> +       if (fence) {
>                  drm_syncobj_replace_fence(syncobj, fence);
> + atomic64_set(&syncobj->binary_payload, fence->seqno);
> +       }
>
>          *out_syncobj = syncobj;
>          return 0;
> @@ -604,6 +606,7 @@ static int 
> drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
>          }
>
>          drm_syncobj_replace_fence(syncobj, fence);
> +       atomic64_set(&syncobj->binary_payload, fence->seqno);
>          dma_fence_put(fence);
>          drm_syncobj_put(syncobj);
>          return 0;
> @@ -1224,8 +1227,10 @@ drm_syncobj_reset_ioctl(struct drm_device *dev, 
> void *data,
>          if (ret < 0)
>                  return ret;
>
> -       for (i = 0; i < args->count_handles; i++)
> +       for (i = 0; i < args->count_handles; i++) {
>                  drm_syncobj_replace_fence(syncobjs[i], NULL);
> + atomic64_set(&syncobjs[i]->binary_payload, 0);
> +       }
>
>          drm_syncobj_array_free(syncobjs, args->count_handles);
>
> @@ -1395,6 +1400,61 @@ int drm_syncobj_query_ioctl(struct drm_device 
> *dev, void *data,
>                  if (ret)
>                          break;
>          }
> +
> +       drm_syncobj_array_free(syncobjs, args->count_handles);
> +
> +       return ret;
> +}
> +
> +int drm_syncobj_binary_ioctl(struct drm_device *dev, void *data,
> +                            struct drm_file *file_private)
> +{
> +       struct drm_syncobj_binary_array *args = data;
> +       struct drm_syncobj **syncobjs;
> +       u32 __user *access_flags = u64_to_user_ptr(args->access_flags);
> +       u64 __user *values = u64_to_user_ptr(args->values);
> +       u32 i;
> +       int ret;
> +
> +       if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
> +               return -EOPNOTSUPP;
> +
> +       if (args->pad != 0)
> +               return -EINVAL;
> +
> +       if (args->count_handles == 0)
> +               return -EINVAL;
> +
> +       ret = drm_syncobj_array_find(file_private,
> + u64_to_user_ptr(args->handles),
> + args->count_handles,
> +                                    &syncobjs);
> +       if (ret < 0)
> +               return ret;
> +
> +       for (i = 0; i < args->count_handles; i++) {
> +               u32 flags;
> +               u64 value;
> +
> +               if (get_user(flags, &access_flags[i])) {
> +                       ret = -EFAULT;
> +                       break;
> +               }
> +
> +               if (flags & DRM_SYNCOBJ_BINARY_VALUE_INC)
> +                       value = 
> atomic64_inc_return(&syncobjs[i]->binary_payload) - 1;
> +               else if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ)
> +                       value = 
> atomic64_read(&syncobjs[i]->binary_payload);
> +
> +               if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) {
> +                       if (put_user(value, &values[i])) {
> +                               ret = -EFAULT;
> +                               break;
> +                       }
> +               }
> +
> +       }
> +
>          drm_syncobj_array_free(syncobjs, args->count_handles);
>
>          return ret;
> diff --git a/include/drm/drm_syncobj.h b/include/drm/drm_syncobj.h
> index 6cf7243a1dc5..aa76cb3f9107 100644
> --- a/include/drm/drm_syncobj.h
> +++ b/include/drm/drm_syncobj.h
> @@ -61,6 +61,15 @@ struct drm_syncobj {
>           * @file: A file backing for this syncobj.
>           */
>          struct file *file;
> +       /**
> +        * @binary_payload: A 64bit payload for binary syncobjs.
> +        *
> +        * We use the payload value to wait on binary syncobj fences to
> +        * materialize. It is a reservation mechanism for the signaler to
> +        * express that at some point in the future a dma fence with 
> the same
> +        * seqno will be put into the syncobj.
> +        */
> +       atomic64_t binary_payload;
>  };
>
>  void drm_syncobj_free(struct kref *kref);
> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
> index 8a5b2f8f8eb9..78a0a413b788 100644
> --- a/include/uapi/drm/drm.h
> +++ b/include/uapi/drm/drm.h
> @@ -785,6 +785,22 @@ struct drm_syncobj_timeline_array {
>          __u32 pad;
>  };
>
> +struct drm_syncobj_binary_array {
> +       /* A pointer to an array of u32 syncobj handles. */
> +       __u64 handles;
> +       /* A pointer to an array of u32 access flags for each handle. */
> +       __u64 access_flags;
> +       /* The binary value of a syncobj is read before it is 
> incremented. */
> +#define DRM_SYNCOBJ_BINARY_VALUE_READ (1u << 0)
> +#define DRM_SYNCOBJ_BINARY_VALUE_INC  (1u << 1)
> +       /* A pointer to an array of u64 values written to by the 
> kernel if the
> +        * handle is flagged for reading.
> +        */
> +       __u64 values;
> +       /* The length of the 3 arrays above. */
> +       __u32 count_handles;
> +       __u32 pad;
> +};
>
>  /* Query current scanout sequence number */
>  struct drm_crtc_get_sequence {
> @@ -946,6 +962,7 @@ extern "C" {
>  #define DRM_IOCTL_SYNCOBJ_QUERY         DRM_IOWR(0xCB, struct 
> drm_syncobj_timeline_array)
>  #define DRM_IOCTL_SYNCOBJ_TRANSFER      DRM_IOWR(0xCC, struct 
> drm_syncobj_transfer)
>  #define DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL DRM_IOWR(0xCD, struct 
> drm_syncobj_timeline_array)
> +#define DRM_IOCTL_SYNCOBJ_BINARY       DRM_IOWR(0xCE, struct 
> drm_syncobj_binary_array)
>
>  /**
>   * Device specific ioctls should only be in their respective headers
> -- 
> 2.23.0
>
Lionel Landwerlin Oct. 18, 2019, 8:59 a.m. UTC | #3
Following earlier discussions in particular with James Jones at Nvidia, 
I think we established this patch/feature is not needed.

This feature was indented to fix a failing test on our implementation.
I've just submitted a MR to delete that test : 
https://gitlab.freedesktop.org/mesa/crucible/merge_requests/55
I think it is invalid.

We should be able to workaround the submission thread race condition 
issue by just resetting a binary semaphore to be signaled in 
vkQueueSubmit before submitting the workload, so that further waits 
happen on the right dma-fence.
This might be a bit more costly (more ioctls) than the feature in this 
patch, so I'm looking for your feedback on this.

Thanks a lot,

-Lionel

On 17/09/2019 16:06, Lionel Landwerlin wrote:
> Thanks David,
>
> I'll try to fix the test to match AMD's restrictions.
>
> The v7 here was to fix another existing test : 
> dEQP-VK.api.external.fence.sync_fd.transference_temporary
>
> Cheers,
>
> -Lionel
>
> On 17/09/2019 15:36, Zhou, David(ChunMing) wrote:
>> Hi Lionel,
>> The update looks good to me.
>> I tried your signal-order test, seems it isn't ready to run, not sure 
>> if I can reproduce your this issue.
>>
>> -David
>> ------------------------------------------------------------------------
>> *From:* Lionel Landwerlin <lionel.g.landwerlin@intel.com>
>> *Sent:* Tuesday, September 17, 2019 7:03 PM
>> *To:* dri-devel@lists.freedesktop.org <dri-devel@lists.freedesktop.org>
>> *Cc:* Lionel Landwerlin <lionel.g.landwerlin@intel.com>; Zhou, 
>> David(ChunMing) <David1.Zhou@amd.com>; Koenig, Christian 
>> <Christian.Koenig@amd.com>; Jason Ekstrand <jason@jlekstrand.net>
>> *Subject:* [PATCH 1/1] drm/syncobj: add sideband payload
>> The Vulkan timeline semaphores allow signaling to happen on the point
>> of the timeline without all of the its dependencies to be created.
>>
>> The current 2 implementations (AMD/Intel) of the Vulkan spec on top of
>> the Linux kernel are using a thread to wait on the dependencies of a
>> given point to materialize and delay actual submission to the kernel
>> driver until the wait completes.
>>
>> If a binary semaphore is submitted for signaling along the side of a
>> timeline semaphore waiting for completion that means that the drm
>> syncobj associated with that binary semaphore will not have a DMA
>> fence associated with it by the time vkQueueSubmit() returns. This and
>> the fact that a binary semaphore can be signaled and unsignaled as
>> before its DMA fences materialize mean that we cannot just rely on the
>> fence within the syncobj but we also need a sideband payload verifying
>> that the fence in the syncobj matches the last submission from the
>> Vulkan API point of view.
>>
>> This change adds a sideband payload that is incremented with signaled
>> syncobj when vkQueueSubmit() is called. The next vkQueueSubmit()
>> waiting on a the syncobj will read the sideband payload and wait for a
>> fence chain element with a seqno superior or equal to the sideband
>> payload value to be added into the fence chain and use that fence to
>> trigger the submission on the kernel driver.
>>
>> v2: Use a separate ioctl to get/set the sideband value (Christian)
>>
>> v3: Use 2 ioctls for get/set (Christian)
>>
>> v4: Use a single new ioctl
>>
>> v5: a bunch of blattant mistakes
>>     Store payload atomically (Chris)
>>
>> v6: Only touch atomic value once (Jason)
>>
>> v7: Updated atomic value when importing sync file
>>
>> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
>> Reviewed-by: David Zhou <David1.Zhou@amd.com> (v6)
>> Cc: Christian Koenig <Christian.Koenig@amd.com>
>> Cc: Jason Ekstrand <jason@jlekstrand.net>
>> Cc: David(ChunMing) Zhou <David1.Zhou@amd.com>
>> ---
>>  drivers/gpu/drm/drm_internal.h |  2 ++
>>  drivers/gpu/drm/drm_ioctl.c    |  3 ++
>>  drivers/gpu/drm/drm_syncobj.c  | 64 ++++++++++++++++++++++++++++++++--
>>  include/drm/drm_syncobj.h      |  9 +++++
>>  include/uapi/drm/drm.h         | 17 +++++++++
>>  5 files changed, 93 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_internal.h 
>> b/drivers/gpu/drm/drm_internal.h
>> index 51a2055c8f18..e297dfd85019 100644
>> --- a/drivers/gpu/drm/drm_internal.h
>> +++ b/drivers/gpu/drm/drm_internal.h
>> @@ -208,6 +208,8 @@ int drm_syncobj_timeline_signal_ioctl(struct 
>> drm_device *dev, void *data,
>>                                        struct drm_file *file_private);
>>  int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
>>                              struct drm_file *file_private);
>> +int drm_syncobj_binary_ioctl(struct drm_device *dev, void *data,
>> +                            struct drm_file *file_private);
>>
>>  /* drm_framebuffer.c */
>>  void drm_framebuffer_print_info(struct drm_printer *p, unsigned int 
>> indent,
>> diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
>> index f675a3bb2c88..644d0bc800a4 100644
>> --- a/drivers/gpu/drm/drm_ioctl.c
>> +++ b/drivers/gpu/drm/drm_ioctl.c
>> @@ -703,6 +703,9 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
>>                        DRM_RENDER_ALLOW),
>>          DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
>>                        DRM_RENDER_ALLOW),
>> +       DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_BINARY, drm_syncobj_binary_ioctl,
>> +                     DRM_RENDER_ALLOW),
>> +
>>          DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, 
>> drm_crtc_get_sequence_ioctl, 0),
>>          DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, 
>> drm_crtc_queue_sequence_ioctl, 0),
>>          DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, 
>> drm_mode_create_lease_ioctl, DRM_MASTER),
>> diff --git a/drivers/gpu/drm/drm_syncobj.c 
>> b/drivers/gpu/drm/drm_syncobj.c
>> index 4b5c7b0ed714..2de8f1380890 100644
>> --- a/drivers/gpu/drm/drm_syncobj.c
>> +++ b/drivers/gpu/drm/drm_syncobj.c
>> @@ -418,8 +418,10 @@ int drm_syncobj_create(struct drm_syncobj 
>> **out_syncobj, uint32_t flags,
>>          if (flags & DRM_SYNCOBJ_CREATE_SIGNALED)
>> drm_syncobj_assign_null_handle(syncobj);
>>
>> -       if (fence)
>> +       if (fence) {
>>                  drm_syncobj_replace_fence(syncobj, fence);
>> + atomic64_set(&syncobj->binary_payload, fence->seqno);
>> +       }
>>
>>          *out_syncobj = syncobj;
>>          return 0;
>> @@ -604,6 +606,7 @@ static int 
>> drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
>>          }
>>
>>          drm_syncobj_replace_fence(syncobj, fence);
>> +       atomic64_set(&syncobj->binary_payload, fence->seqno);
>>          dma_fence_put(fence);
>>          drm_syncobj_put(syncobj);
>>          return 0;
>> @@ -1224,8 +1227,10 @@ drm_syncobj_reset_ioctl(struct drm_device 
>> *dev, void *data,
>>          if (ret < 0)
>>                  return ret;
>>
>> -       for (i = 0; i < args->count_handles; i++)
>> +       for (i = 0; i < args->count_handles; i++) {
>>                  drm_syncobj_replace_fence(syncobjs[i], NULL);
>> + atomic64_set(&syncobjs[i]->binary_payload, 0);
>> +       }
>>
>>          drm_syncobj_array_free(syncobjs, args->count_handles);
>>
>> @@ -1395,6 +1400,61 @@ int drm_syncobj_query_ioctl(struct drm_device 
>> *dev, void *data,
>>                  if (ret)
>>                          break;
>>          }
>> +
>> +       drm_syncobj_array_free(syncobjs, args->count_handles);
>> +
>> +       return ret;
>> +}
>> +
>> +int drm_syncobj_binary_ioctl(struct drm_device *dev, void *data,
>> +                            struct drm_file *file_private)
>> +{
>> +       struct drm_syncobj_binary_array *args = data;
>> +       struct drm_syncobj **syncobjs;
>> +       u32 __user *access_flags = u64_to_user_ptr(args->access_flags);
>> +       u64 __user *values = u64_to_user_ptr(args->values);
>> +       u32 i;
>> +       int ret;
>> +
>> +       if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
>> +               return -EOPNOTSUPP;
>> +
>> +       if (args->pad != 0)
>> +               return -EINVAL;
>> +
>> +       if (args->count_handles == 0)
>> +               return -EINVAL;
>> +
>> +       ret = drm_syncobj_array_find(file_private,
>> + u64_to_user_ptr(args->handles),
>> + args->count_handles,
>> +                                    &syncobjs);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       for (i = 0; i < args->count_handles; i++) {
>> +               u32 flags;
>> +               u64 value;
>> +
>> +               if (get_user(flags, &access_flags[i])) {
>> +                       ret = -EFAULT;
>> +                       break;
>> +               }
>> +
>> +               if (flags & DRM_SYNCOBJ_BINARY_VALUE_INC)
>> +                       value = 
>> atomic64_inc_return(&syncobjs[i]->binary_payload) - 1;
>> +               else if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ)
>> +                       value = 
>> atomic64_read(&syncobjs[i]->binary_payload);
>> +
>> +               if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) {
>> +                       if (put_user(value, &values[i])) {
>> +                               ret = -EFAULT;
>> +                               break;
>> +                       }
>> +               }
>> +
>> +       }
>> +
>>          drm_syncobj_array_free(syncobjs, args->count_handles);
>>
>>          return ret;
>> diff --git a/include/drm/drm_syncobj.h b/include/drm/drm_syncobj.h
>> index 6cf7243a1dc5..aa76cb3f9107 100644
>> --- a/include/drm/drm_syncobj.h
>> +++ b/include/drm/drm_syncobj.h
>> @@ -61,6 +61,15 @@ struct drm_syncobj {
>>           * @file: A file backing for this syncobj.
>>           */
>>          struct file *file;
>> +       /**
>> +        * @binary_payload: A 64bit payload for binary syncobjs.
>> +        *
>> +        * We use the payload value to wait on binary syncobj fences to
>> +        * materialize. It is a reservation mechanism for the signaler to
>> +        * express that at some point in the future a dma fence with 
>> the same
>> +        * seqno will be put into the syncobj.
>> +        */
>> +       atomic64_t binary_payload;
>>  };
>>
>>  void drm_syncobj_free(struct kref *kref);
>> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
>> index 8a5b2f8f8eb9..78a0a413b788 100644
>> --- a/include/uapi/drm/drm.h
>> +++ b/include/uapi/drm/drm.h
>> @@ -785,6 +785,22 @@ struct drm_syncobj_timeline_array {
>>          __u32 pad;
>>  };
>>
>> +struct drm_syncobj_binary_array {
>> +       /* A pointer to an array of u32 syncobj handles. */
>> +       __u64 handles;
>> +       /* A pointer to an array of u32 access flags for each handle. */
>> +       __u64 access_flags;
>> +       /* The binary value of a syncobj is read before it is 
>> incremented. */
>> +#define DRM_SYNCOBJ_BINARY_VALUE_READ (1u << 0)
>> +#define DRM_SYNCOBJ_BINARY_VALUE_INC  (1u << 1)
>> +       /* A pointer to an array of u64 values written to by the 
>> kernel if the
>> +        * handle is flagged for reading.
>> +        */
>> +       __u64 values;
>> +       /* The length of the 3 arrays above. */
>> +       __u32 count_handles;
>> +       __u32 pad;
>> +};
>>
>>  /* Query current scanout sequence number */
>>  struct drm_crtc_get_sequence {
>> @@ -946,6 +962,7 @@ extern "C" {
>>  #define DRM_IOCTL_SYNCOBJ_QUERY         DRM_IOWR(0xCB, struct 
>> drm_syncobj_timeline_array)
>>  #define DRM_IOCTL_SYNCOBJ_TRANSFER      DRM_IOWR(0xCC, struct 
>> drm_syncobj_transfer)
>>  #define DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL DRM_IOWR(0xCD, struct 
>> drm_syncobj_timeline_array)
>> +#define DRM_IOCTL_SYNCOBJ_BINARY       DRM_IOWR(0xCE, struct 
>> drm_syncobj_binary_array)
>>
>>  /**
>>   * Device specific ioctls should only be in their respective headers
>> -- 
>> 2.23.0
>>
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index 51a2055c8f18..e297dfd85019 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -208,6 +208,8 @@  int drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
 				      struct drm_file *file_private);
 int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
 			    struct drm_file *file_private);
+int drm_syncobj_binary_ioctl(struct drm_device *dev, void *data,
+			     struct drm_file *file_private);
 
 /* drm_framebuffer.c */
 void drm_framebuffer_print_info(struct drm_printer *p, unsigned int indent,
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index f675a3bb2c88..644d0bc800a4 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -703,6 +703,9 @@  static const struct drm_ioctl_desc drm_ioctls[] = {
 		      DRM_RENDER_ALLOW),
 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
 		      DRM_RENDER_ALLOW),
+	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_BINARY, drm_syncobj_binary_ioctl,
+		      DRM_RENDER_ALLOW),
+
 	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index 4b5c7b0ed714..2de8f1380890 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -418,8 +418,10 @@  int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 	if (flags & DRM_SYNCOBJ_CREATE_SIGNALED)
 		drm_syncobj_assign_null_handle(syncobj);
 
-	if (fence)
+	if (fence) {
 		drm_syncobj_replace_fence(syncobj, fence);
+		atomic64_set(&syncobj->binary_payload, fence->seqno);
+	}
 
 	*out_syncobj = syncobj;
 	return 0;
@@ -604,6 +606,7 @@  static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
 	}
 
 	drm_syncobj_replace_fence(syncobj, fence);
+	atomic64_set(&syncobj->binary_payload, fence->seqno);
 	dma_fence_put(fence);
 	drm_syncobj_put(syncobj);
 	return 0;
@@ -1224,8 +1227,10 @@  drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,
 	if (ret < 0)
 		return ret;
 
-	for (i = 0; i < args->count_handles; i++)
+	for (i = 0; i < args->count_handles; i++) {
 		drm_syncobj_replace_fence(syncobjs[i], NULL);
+		atomic64_set(&syncobjs[i]->binary_payload, 0);
+	}
 
 	drm_syncobj_array_free(syncobjs, args->count_handles);
 
@@ -1395,6 +1400,61 @@  int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
 		if (ret)
 			break;
 	}
+
+	drm_syncobj_array_free(syncobjs, args->count_handles);
+
+	return ret;
+}
+
+int drm_syncobj_binary_ioctl(struct drm_device *dev, void *data,
+			     struct drm_file *file_private)
+{
+	struct drm_syncobj_binary_array *args = data;
+	struct drm_syncobj **syncobjs;
+	u32 __user *access_flags = u64_to_user_ptr(args->access_flags);
+	u64 __user *values = u64_to_user_ptr(args->values);
+	u32 i;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
+		return -EOPNOTSUPP;
+
+	if (args->pad != 0)
+		return -EINVAL;
+
+	if (args->count_handles == 0)
+		return -EINVAL;
+
+	ret = drm_syncobj_array_find(file_private,
+				     u64_to_user_ptr(args->handles),
+				     args->count_handles,
+				     &syncobjs);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < args->count_handles; i++) {
+		u32 flags;
+		u64 value;
+
+		if (get_user(flags, &access_flags[i])) {
+			ret = -EFAULT;
+			break;
+		}
+
+		if (flags & DRM_SYNCOBJ_BINARY_VALUE_INC)
+			value = atomic64_inc_return(&syncobjs[i]->binary_payload) - 1;
+		else if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ)
+			value = atomic64_read(&syncobjs[i]->binary_payload);
+
+		if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) {
+			if (put_user(value, &values[i])) {
+				ret = -EFAULT;
+				break;
+			}
+		}
+
+	}
+
 	drm_syncobj_array_free(syncobjs, args->count_handles);
 
 	return ret;
diff --git a/include/drm/drm_syncobj.h b/include/drm/drm_syncobj.h
index 6cf7243a1dc5..aa76cb3f9107 100644
--- a/include/drm/drm_syncobj.h
+++ b/include/drm/drm_syncobj.h
@@ -61,6 +61,15 @@  struct drm_syncobj {
 	 * @file: A file backing for this syncobj.
 	 */
 	struct file *file;
+	/**
+	 * @binary_payload: A 64bit payload for binary syncobjs.
+	 *
+	 * We use the payload value to wait on binary syncobj fences to
+	 * materialize. It is a reservation mechanism for the signaler to
+	 * express that at some point in the future a dma fence with the same
+	 * seqno will be put into the syncobj.
+	 */
+	atomic64_t binary_payload;
 };
 
 void drm_syncobj_free(struct kref *kref);
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index 8a5b2f8f8eb9..78a0a413b788 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -785,6 +785,22 @@  struct drm_syncobj_timeline_array {
 	__u32 pad;
 };
 
+struct drm_syncobj_binary_array {
+	/* A pointer to an array of u32 syncobj handles. */
+	__u64 handles;
+	/* A pointer to an array of u32 access flags for each handle. */
+	__u64 access_flags;
+	/* The binary value of a syncobj is read before it is incremented. */
+#define DRM_SYNCOBJ_BINARY_VALUE_READ (1u << 0)
+#define DRM_SYNCOBJ_BINARY_VALUE_INC  (1u << 1)
+	/* A pointer to an array of u64 values written to by the kernel if the
+	 * handle is flagged for reading.
+	 */
+	__u64 values;
+	/* The length of the 3 arrays above. */
+	__u32 count_handles;
+	__u32 pad;
+};
 
 /* Query current scanout sequence number */
 struct drm_crtc_get_sequence {
@@ -946,6 +962,7 @@  extern "C" {
 #define DRM_IOCTL_SYNCOBJ_QUERY		DRM_IOWR(0xCB, struct drm_syncobj_timeline_array)
 #define DRM_IOCTL_SYNCOBJ_TRANSFER	DRM_IOWR(0xCC, struct drm_syncobj_transfer)
 #define DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL	DRM_IOWR(0xCD, struct drm_syncobj_timeline_array)
+#define DRM_IOCTL_SYNCOBJ_BINARY	DRM_IOWR(0xCE, struct drm_syncobj_binary_array)
 
 /**
  * Device specific ioctls should only be in their respective headers