ee7cd8981e
A virtio driver does virtqueue_add_buf() multiple times before finally calling virtqueue_kick(); previously we only exposed the added buffers in the virtqueue_kick() call. This means we don't need a memory barrier in virtqueue_add_buf(), but it reduces concurrency as the device (ie. host) can't see the buffers until the kick. In the unusual (but now possible) case where a driver does add_buf() and get_buf() without doing a kick, we do need to insert one before our counter wraps. Otherwise we could wrap num_added, and later on not realize that we have passed the marker where we should have kicked. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> |
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| .. | ||
| config.c | ||
| Kconfig | ||
| Makefile | ||
| virtio.c | ||
| virtio_balloon.c | ||
| virtio_mmio.c | ||
| virtio_pci.c | ||
| virtio_ring.c | ||