similar to: [PATCH v4 1/2] drm/virtio: Rewrite virtio_gpu_queue_ctrl_buffer using fenced version.

Factor function in preparation to generating scatterlist prior to locking. Signed-off-by: David Riley <davidriley at chromium.org> --- drivers/gpu/drm/virtio/virtgpu_vq.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 981ee16e3ee9..bf5a4a50b002 100644 ---

Factor function in preparation to generating scatterlist prior to locking. Signed-off-by: David Riley <davidriley at chromium.org> --- drivers/gpu/drm/virtio/virtgpu_vq.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 981ee16e3ee9..bf5a4a50b002 100644 ---

Userspace requested command buffer allocations could be too large to make as a contiguous allocation. Use vmalloc if necessary to satisfy those allocations. Signed-off-by: David Riley <davidriley at chromium.org> --- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 4 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 78 +++++++++++++++++++++++--- 2 files changed, 72 insertions(+), 10 deletions(-)

Userspace requested command buffer allocations could be too large to make as a contiguous allocation. Use vmalloc if necessary to satisfy those allocations. Signed-off-by: David Riley <davidriley at chromium.org> --- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 4 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 79 +++++++++++++++++++++++--- 2 files changed, 73 insertions(+), 10 deletions(-)

Userspace requested command buffer allocations could be too large to make as a contiguous allocation. Use vmalloc if necessary to satisfy those allocations. Signed-off-by: David Riley <davidriley at chromium.org> --- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 4 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 114 ++++++++++++++++++++----- 2 files changed, 96 insertions(+), 22 deletions(-)

Userspace requested command buffer allocations could be too large to make as a contiguous allocation. Use vmalloc if necessary to satisfy those allocations. Signed-off-by: David Riley <davidriley at chromium.org> --- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 4 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 114 ++++++++++++++++++++----- 2 files changed, 96 insertions(+), 22 deletions(-)

Make the queue functions return void, none of the call sites checks the return value. Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_vq.c | 41 ++++++++++------------------- 1 file changed, 14 insertions(+), 27 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 7ac20490e1b4..ca91e83ffaef 100644

Split virtqueue_kick() call into virtqueue_kick_prepare(), which requires serialization, and virtqueue_notify(), which does not. Move the virtqueue_notify() call out of the critical section protected by the queue lock. This avoids triggering a vmexit while holding the lock and thereby fixes a rather bad spinlock contention. Suggested-by: Chia-I Wu <olvaffe at gmail.com> Signed-off-by:

Add helper function to handle the submission of fenced control requests. Make sure we initialize the fence while holding the virtqueue lock, so requests can't be reordered. Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_fence.c | 2 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 40 +++++++++++++++++++++++++++++----- 2 files changed, 35

Add helper function to handle the submission of fenced control requests. Make sure we initialize the fence while holding the virtqueue lock, so requests can't be reordered. Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_fence.c | 2 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 40 +++++++++++++++++++++++++++++----- 2 files changed, 35

Add helper function to handle the submission of fenced control requests. Make sure we initialize the fence while holding the virtqueue lock, so requests can't be reordered. Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_fence.c | 2 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 40 +++++++++++++++++++++++++++++----- 2 files changed, 35

Add helper function to handle the submission of fenced control requests. Make sure we initialize the fence while holding the virtqueue lock, so requests can't be reordered. Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_fence.c | 2 +- drivers/gpu/drm/virtio/virtgpu_vq.c | 40 +++++++++++++++++++++++++++++----- 2 files changed, 35

Replace virtqueue_kick by virtqueue_kick_prepare, which requires serialization, and virtqueue_notify, which does not. Repurpose the return values to indicate whether the vq should be notified. This fixes a lock contention with qemu host. When the guest calls vibad rtqueue_notify, the qemu vcpu thread exits the guest and waits for the qemu iothread to perform the MMIO. If the qemu iothread is

Replace virtqueue_kick by virtqueue_kick_prepare, which requires serialization, and virtqueue_notify, which does not. Repurpose the return values to indicate whether the vq should be notified. This fixes a lock contention with qemu host. When the guest calls vibad rtqueue_notify, the qemu vcpu thread exits the guest and waits for the qemu iothread to perform the MMIO. If the qemu iothread is

Replace virtqueue_kick by virtqueue_kick_prepare, which requires serialization, and virtqueue_notify, which does not. Repurpose the return values to indicate whether the vq should be notified. This fixes a bad spinlock contention when the host is qemu. When the guest calls virtqueue_notify, the qemu vcpu thread exits the guest and waits for the qemu iothread to perform the MMIO. If the qemu

Only call virtio_gpu_array_add_fence if we actually have a fence. Fixes: da758d51968a ("drm/virtio: rework virtio_gpu_execbuffer_ioctl fencing") Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_vq.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c

Only call virtio_gpu_array_add_fence if we actually have a fence. Fixes: da758d51968a ("drm/virtio: rework virtio_gpu_execbuffer_ioctl fencing") Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_vq.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c

When the driver submits multiple commands in a row it makes sense to notify the host only after submitting the last one, so the host can process them all at once, with a single vmexit. Add functions to enable/disable notifications to allow that. Use the new functions for primary plane updates. Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_drv.h

When the driver submits multiple commands in a row it makes sense to notify the host only after submitting the last one, so the host can process them all at once, with a single vmexit. Add functions to enable/disable notifications to allow that. Use the new functions for primary plane updates. Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> --- drivers/gpu/drm/virtio/virtgpu_drv.h

Fix warning introduced with commit e1218b8c0cc1 ("drm/virtio: Use vmalloc for command buffer allocations.") from drm-misc-next. Signed-off-by: David Riley <davidriley at chromium.org> --- drivers/gpu/drm/virtio/virtgpu_vq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index