| Message ID | 20190809134349.4102-2-lionel.g.landwerlin@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/syncobj: add syncobj sideband payload for threaded submission | expand |
If it is not submitted yet, Reviewed-by: Chunming Zhou <david1.zhou@amd.com> -David On 2019年08月09日 21:43, Lionel Landwerlin wrote: > 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) > > Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> > 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 | 58 +++++++++++++++++++++++++++++++++- > include/drm/drm_syncobj.h | 9 ++++++ > include/uapi/drm/drm.h | 17 ++++++++++ > 5 files changed, 88 insertions(+), 1 deletion(-) > > 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 b927e482e554..d2d3a8d1374d 100644 > --- a/drivers/gpu/drm/drm_syncobj.c > +++ b/drivers/gpu/drm/drm_syncobj.c > @@ -1150,8 +1150,10 @@ 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); > > @@ -1321,6 +1323,60 @@ 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; > + > + if (get_user(flags, &access_flags[i])) { > + ret = -EFAULT; > + break; > + } > + > + > + if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) { > + u64 value = atomic64_read(&syncobjs[i]->binary_payload); > + > + if (put_user(value, &values[i])) { > + ret = -EFAULT; > + break; > + } > + } > + > + if (flags & DRM_SYNCOBJ_BINARY_VALUE_INC) > + atomic64_inc(&syncobjs[i]->binary_payload); > + } > + > 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
On Fri, Aug 9, 2019 at 8:43 AM Lionel Landwerlin < lionel.g.landwerlin@intel.com> wrote: > 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) > > Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> > 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 | 58 +++++++++++++++++++++++++++++++++- > include/drm/drm_syncobj.h | 9 ++++++ > include/uapi/drm/drm.h | 17 ++++++++++ > 5 files changed, 88 insertions(+), 1 deletion(-) > > 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 b927e482e554..d2d3a8d1374d 100644 > --- a/drivers/gpu/drm/drm_syncobj.c > +++ b/drivers/gpu/drm/drm_syncobj.c > @@ -1150,8 +1150,10 @@ 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); > > @@ -1321,6 +1323,60 @@ 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; > + > + if (get_user(flags, &access_flags[i])) { > + ret = -EFAULT; > + break; > + } > + > + > + if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) { > + u64 value = > atomic64_read(&syncobjs[i]->binary_payload); > + > + if (put_user(value, &values[i])) { > + ret = -EFAULT; > + break; > + } > + } > + > + if (flags & DRM_SYNCOBJ_BINARY_VALUE_INC) > + atomic64_inc(&syncobjs[i]->binary_payload); > You go out of your way to use atomics but then don't bother to do the read and increment atomically. Maybe something like u64 value = 0; if (flags & DRM_SYNCOBJ_BINARY_VALUE_INC) value = atomic64_inc(...); else if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) value = atomic64_read(...); if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) put_user(...) --Jason > + } > + > 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.rc1 > >
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 b927e482e554..d2d3a8d1374d 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -1150,8 +1150,10 @@ 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); @@ -1321,6 +1323,60 @@ 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; + + if (get_user(flags, &access_flags[i])) { + ret = -EFAULT; + break; + } + + + if (flags & DRM_SYNCOBJ_BINARY_VALUE_READ) { + u64 value = atomic64_read(&syncobjs[i]->binary_payload); + + if (put_user(value, &values[i])) { + ret = -EFAULT; + break; + } + } + + if (flags & DRM_SYNCOBJ_BINARY_VALUE_INC) + atomic64_inc(&syncobjs[i]->binary_payload); + } + 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
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) Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> 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 | 58 +++++++++++++++++++++++++++++++++- include/drm/drm_syncobj.h | 9 ++++++ include/uapi/drm/drm.h | 17 ++++++++++ 5 files changed, 88 insertions(+), 1 deletion(-)