ddd89d0a05
Currently the doorbell is relayed via eventfd which may have significant overhead because of the cost of vmexits or syscall. This patch introduces mmap() based doorbell mapping which can eliminate the overhead caused by vmexit or syscall. To ease the userspace modeling of the doorbell layout (usually virtio-pci), this patch starts from a doorbell per page model. Vhost-vdpa only support the hardware doorbell that sit at the boundary of a page and does not share the page with other registers. Doorbell of each virtqueue must be mapped separately, pgoff is the index of the virtqueue. This allows userspace to map a subset of the doorbell which may be useful for the implementation of software assisted virtqueue (control vq) in the future. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200529080303.15449-5-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> |
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| .. | ||
| iotlb.c | ||
| Kconfig | ||
| Makefile | ||
| net.c | ||
| scsi.c | ||
| test.c | ||
| test.h | ||
| vdpa.c | ||
| vhost.c | ||
| vhost.h | ||
| vringh.c | ||
| vsock.c | ||