There are two problems with the current method of determining the
virtio-gpu debug name.
1) TASK_COMM_LEN is defined to be 16 bytes only, and this is a
Linux kernel idiom (see PR_SET_NAME + PR_GET_NAME). Though,
Android/FreeBSD get around this via setprogname(..)/getprogname(..)
in libc.
On Android, names longer than 16 bytes are common. For example,
one often encounters a program like "com.android.systemui".
The virtio-gpu spec allows the debug name to be up to 64 bytes, so
ideally userspace should be able to set debug names up to 64 bytes.
2) The current implementation determines the debug name using whatever
task initiated virtgpu. This is could be a "RenderThread" of a
larger program, when we actually want to propagate the debug name
of the program.
To fix these issues, add a new CONTEXT_INIT param that allows userspace
to set the debug name when creating a context.
It takes a null-terminated C-string as the param value. The length of the
string (excluding the terminator) **should** be <= 64 bytes. Otherwise,
the debug_name will be truncated to 64 bytes.
Link to open-source userspace:
https://android-review.googlesource.com/c/platform/hardware/google/gfxstream/+/2787176
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Josh Simonot <josh.simonot@gmail.com>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231018181727.772-2-gurchetansingh@chromium.org
DRM API requires the DRM's driver to be backed with the device that can
be used for generic DMA operations. The VirtIO-GPU device can't perform
DMA operations if it uses PCI transport because PCI device driver creates
a virtual VirtIO-GPU device that isn't associated with the PCI. Use PCI's
GPU device for the DRM's device instead of the VirtIO-GPU device and drop
DMA-related hacks from the VirtIO-GPU driver.
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220630200726.1884320-8-dmitry.osipenko@collabora.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The current virtgpu implementation of poll(..) drops events
when VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK is enabled (otherwise
it's like a normal DRM driver).
This is because paravirtualized userspaces receives responses in a
buffer of type BLOB_MEM_GUEST, not by read(..).
To be in line with other DRM drivers and avoid specialized behavior,
it is possible to define a dummy event for virtgpu. Paravirtualized
userspace will now have to call read(..) on the DRM fd to receive the
dummy event.
Fixes: b10790434c ("drm/virtgpu api: create context init feature")
Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20211122232210.602-2-gurchetansingh@google.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Similar to DRM_VMW_EVENT_FENCE_SIGNALED. Sends a pollable event
to the DRM file descriptor when a fence on a specific ring is
signaled.
One difference is the event is not exposed via the UAPI -- this is
because host responses are on a shared memory buffer of type
BLOB_MEM_GUEST [this is the common way to receive responses with
virtgpu]. As such, there is no context specific read(..)
implementation either -- just a poll(..) implementation.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Nicholas Verne <nverne@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-12-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
For the Sommelier guest Wayland proxy, it's desirable for the
DRM fd to be pollable in response to an host compositor event.
This can also be used by the 3D driver to poll events on a CPU
timeline.
This enables the DRM fd associated with a particular 3D context
to be polled independent of KMS events. The parameter
VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK specifies the pollable
rings.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Nicholas Verne <nverne@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-11-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
These were defined in the previous commit. We'll need these
parameters when allocating a dma_fence. The use case for this
is multiple synchronizations timelines.
The maximum number of timelines per 3D instance will be 32. Usually,
only 2 are needed -- one for CPU commands, and another for GPU
commands.
As such, we'll need to specify these parameters when allocating a
dma_fence.
vgdev->fence_drv.context is the "default" fence context for 2D mode
and old userspace.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-8-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Each fence should be associated with a [fence ID, fence_context,
seqno]. The seqno number is just the fence id.
To get the fence context, we add the ring_idx to the 3D context's
base_fence_ctx. The ring_idx is between 0 and 31, inclusive.
Each 3D context will have it's own base_fence_ctx. The ring_idx will
be emitted to host userspace, when emit_fence_info is true.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-7-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This implements the context initialization ioctl. A list of params
is passed in by userspace, and kernel driver validates them. The
only currently supported param is VIRTGPU_CONTEXT_PARAM_CAPSET_ID.
If the context has already been initialized, -EEXIST is returned.
This happens after Linux userspace does dumb_create + followed by
opening the Mesa virgl driver with the same virtgpu instance.
However, for most applications, 3D contexts will be explicitly
initialized when the feature is available.
Signed-off-by: Anthoine Bourgeois <anthoine.bourgeois@gmail.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-6-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This an incremental refactor towards multiple dma-fence contexts
in virtio-gpu. Since all fences are still allocated using
&virtio_gpu_fence_driver.context, nothing should break and every
processed fence will be signaled.
The overall idea is every 3D context can allocate a number of
dma-fence contexts. Each dma-fence context refers to it's own
timeline.
For example, consider the following case where virgl submits
commands to the GPU (fence ids 1, 3) and does a metadata query with
the CPU (fence id 5). In a different process, gfxstream submits
commands to the GPU (fence ids 2, 4).
fence_id (&dma_fence.seqno) | 1 2 3 4 5
----------------------------------|-----------
fence_ctx 0 (virgl gpu) | 1 3
fence_ctx 1 (virgl metadata query)| 5
fence_ctx 2 (gfxstream gpu) | 2 4
With multiple fence contexts, we can wait for the metadata query
to finish without waiting for the virgl gpu to finish. virgl gpu
does not have to wait for gfxstream gpu. The fence id still is the
monotonically increasing sequence number, but it's only revelant to
the specific dma-fence context.
To fully enable this feature, we'll need to:
- have each 3d context allocate a number of fence contexts. Not
too hard with explicit context initialization on the horizon.
- have guest userspace specify fence context when performing
ioctls.
- tag each fence emitted to the host with the fence context
information. virtio_gpu_ctrl_hdr has padding + flags available,
so that should be easy.
This change goes in the direction specified above, by:
- looking up the virtgpu_fence given a fence_id
- signalling all prior fences in a given context
- signalling current fence
v2: fix grammar in comment
v3: add r-b tags
Reviewed-by: Anthoine Bourgeois <anthoine.bourgeois@gmail.com>
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20201201021623.619-3-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The old transfer ioctls may work on blob resources, and there is no
TRANSFER_BLOB hypercall now for simplicity.
The guest may have a image view on the blob resources such that the
stride is not equal to width * bytes_per_pixel.
For host-only blobs, we can repurpose the transfer ioctls to synchronize
caches as well. For guest-only blobs, these operations are undefined
for now so leave them out.
Also, with seamless Wayland integration between guest/host looking
increasingly attractive, it also makes sense to keep track of
one value for stride.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-16-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Drop the virtio_gpu_{disable,enable}_notify(). Add a new
virtio_gpu_notify() call instead, which must be called whenever
the driver wants make sure the host is notified needed.
Drop automatic notification from command submission. Add
virtio_gpu_notify() calls after each command query instead.
This allows more fine-grained control over host notification
and can move around the notify calls in subsequent patches to
batch command submissions. With this in place it is also
possible to make notification optional for userspace ioctls.
Page flip batching goes away (temporarely).
v3:
- move batching to separate patches.
v2:
- rebase to latest drm-misc-next.
- use "if (!atomic_read())".
- add review & test tags.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Tested-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200214125535.26349-2-kraxel@redhat.com
