Wait until we have enough space in the virt queue to actually queue up
our request. Avoids the guest spinning in case we have a non-zero
amount of free entries but not enough for the request.
Cc: stable at vger.kernel.org
Reported-by: Alain Magloire <amagloire at blackberry.com>
Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
---
drivers/gpu/drm/virtio/virtgpu_vq.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c
b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 48e4f1df6e..020070d483 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -293,7 +293,7 @@ static int virtio_gpu_queue_ctrl_buffer_locked(struct
virtio_gpu_device *vgdev,
ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC);
if (ret == -ENOSPC) {
spin_unlock(&vgdev->ctrlq.qlock);
- wait_event(vgdev->ctrlq.ack_queue, vq->num_free);
+ wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt + incnt);
spin_lock(&vgdev->ctrlq.qlock);
goto retry;
} else {
@@ -368,7 +368,7 @@ static int virtio_gpu_queue_cursor(struct virtio_gpu_device
*vgdev,
ret = virtqueue_add_sgs(vq, sgs, outcnt, 0, vbuf, GFP_ATOMIC);
if (ret == -ENOSPC) {
spin_unlock(&vgdev->cursorq.qlock);
- wait_event(vgdev->cursorq.ack_queue, vq->num_free);
+ wait_event(vgdev->cursorq.ack_queue, vq->num_free >= outcnt);
spin_lock(&vgdev->cursorq.qlock);
goto retry;
} else {
--
2.9.3
On Tue, Apr 03, 2018 at 11:59:04AM +0200, Gerd Hoffmann wrote:> Wait until we have enough space in the virt queue to actually queue up > our request. Avoids the guest spinning in case we have a non-zero > amount of free entries but not enough for the request.Ping airlied, can you please either pick it up or review so I can commit myself? thanks, Gerd> Cc: stable at vger.kernel.org > Reported-by: Alain Magloire <amagloire at blackberry.com> > Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> > --- > drivers/gpu/drm/virtio/virtgpu_vq.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c > index 48e4f1df6e..020070d483 100644 > --- a/drivers/gpu/drm/virtio/virtgpu_vq.c > +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c > @@ -293,7 +293,7 @@ static int virtio_gpu_queue_ctrl_buffer_locked(struct virtio_gpu_device *vgdev, > ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC); > if (ret == -ENOSPC) { > spin_unlock(&vgdev->ctrlq.qlock); > - wait_event(vgdev->ctrlq.ack_queue, vq->num_free); > + wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt + incnt); > spin_lock(&vgdev->ctrlq.qlock); > goto retry; > } else { > @@ -368,7 +368,7 @@ static int virtio_gpu_queue_cursor(struct virtio_gpu_device *vgdev, > ret = virtqueue_add_sgs(vq, sgs, outcnt, 0, vbuf, GFP_ATOMIC); > if (ret == -ENOSPC) { > spin_unlock(&vgdev->cursorq.qlock); > - wait_event(vgdev->cursorq.ack_queue, vq->num_free); > + wait_event(vgdev->cursorq.ack_queue, vq->num_free >= outcnt); > spin_lock(&vgdev->cursorq.qlock); > goto retry; > } else { > -- > 2.9.3 >
Reviewed-by: Dave Airlie <airlied at redhat.com> On Fri., 20 Apr. 2018, 17:23 Gerd Hoffmann, <kraxel at redhat.com> wrote:> On Tue, Apr 03, 2018 at 11:59:04AM +0200, Gerd Hoffmann wrote: > > Wait until we have enough space in the virt queue to actually queue up > > our request. Avoids the guest spinning in case we have a non-zero > > amount of free entries but not enough for the request. > > Ping airlied, can you please either pick it up or review so I can commit > myself? > > thanks, > Gerd > > > Cc: stable at vger.kernel.org > > Reported-by: Alain Magloire <amagloire at blackberry.com> > > Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> > > --- > > drivers/gpu/drm/virtio/virtgpu_vq.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c > b/drivers/gpu/drm/virtio/virtgpu_vq.c > > index 48e4f1df6e..020070d483 100644 > > --- a/drivers/gpu/drm/virtio/virtgpu_vq.c > > +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c > > @@ -293,7 +293,7 @@ static int > virtio_gpu_queue_ctrl_buffer_locked(struct virtio_gpu_device *vgdev, > > ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC); > > if (ret == -ENOSPC) { > > spin_unlock(&vgdev->ctrlq.qlock); > > - wait_event(vgdev->ctrlq.ack_queue, vq->num_free); > > + wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt > + incnt); > > spin_lock(&vgdev->ctrlq.qlock); > > goto retry; > > } else { > > @@ -368,7 +368,7 @@ static int virtio_gpu_queue_cursor(struct > virtio_gpu_device *vgdev, > > ret = virtqueue_add_sgs(vq, sgs, outcnt, 0, vbuf, GFP_ATOMIC); > > if (ret == -ENOSPC) { > > spin_unlock(&vgdev->cursorq.qlock); > > - wait_event(vgdev->cursorq.ack_queue, vq->num_free); > > + wait_event(vgdev->cursorq.ack_queue, vq->num_free >> outcnt); > > spin_lock(&vgdev->cursorq.qlock); > > goto retry; > > } else { > > -- > > 2.9.3 > > > _______________________________________________ > dri-devel mailing list > dri-devel at lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linuxfoundation.org/pipermail/virtualization/attachments/20180420/f5d23877/attachment-0001.html>
On 20 April 2018 at 17:22, Gerd Hoffmann <kraxel at redhat.com> wrote:> On Tue, Apr 03, 2018 at 11:59:04AM +0200, Gerd Hoffmann wrote: >> Wait until we have enough space in the virt queue to actually queue up >> our request. Avoids the guest spinning in case we have a non-zero >> amount of free entries but not enough for the request. > > Ping airlied, can you please either pick it up or review so I can commit > myself?Just in case it got lost from my phone, Reviewed-by: Dave Airlie <airlied at redhat.com>> > thanks, > Gerd > >> Cc: stable at vger.kernel.org >> Reported-by: Alain Magloire <amagloire at blackberry.com> >> Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> >> --- >> drivers/gpu/drm/virtio/virtgpu_vq.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c >> index 48e4f1df6e..020070d483 100644 >> --- a/drivers/gpu/drm/virtio/virtgpu_vq.c >> +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c >> @@ -293,7 +293,7 @@ static int virtio_gpu_queue_ctrl_buffer_locked(struct virtio_gpu_device *vgdev, >> ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC); >> if (ret == -ENOSPC) { >> spin_unlock(&vgdev->ctrlq.qlock); >> - wait_event(vgdev->ctrlq.ack_queue, vq->num_free); >> + wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt + incnt); >> spin_lock(&vgdev->ctrlq.qlock); >> goto retry; >> } else { >> @@ -368,7 +368,7 @@ static int virtio_gpu_queue_cursor(struct virtio_gpu_device *vgdev, >> ret = virtqueue_add_sgs(vq, sgs, outcnt, 0, vbuf, GFP_ATOMIC); >> if (ret == -ENOSPC) { >> spin_unlock(&vgdev->cursorq.qlock); >> - wait_event(vgdev->cursorq.ack_queue, vq->num_free); >> + wait_event(vgdev->cursorq.ack_queue, vq->num_free >= outcnt); >> spin_lock(&vgdev->cursorq.qlock); >> goto retry; >> } else { >> -- >> 2.9.3 >> > _______________________________________________ > dri-devel mailing list > dri-devel at lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
Apparently Analagous Threads
- [PATCH] drm/virtio: fix vq wait_event condition
- [PATCH] drm/virtio: fix vq wait_event condition
- [PATCH v3 2/2] drm/virtio: Use vmalloc for command buffer allocations.
- [PATCH 2/2] drm/virtio: notify virtqueues without holding spinlock
- [PATCH v4 2/2] drm/virtio: Use vmalloc for command buffer allocations.