bd58ab40c3
virtio_queue_aio_detach_host_notifier() does two things: 1. It removes the fd handler from the event loop. 2. It processes the virtqueue one last time. The first step can be peformed by any thread and without taking the AioContext lock. The second step may need the AioContext lock (depending on the device implementation) and runs in the thread where request processing takes place. virtio-blk and virtio-scsi therefore call virtio_queue_aio_detach_host_notifier() from a BH that is scheduled in AioContext. The next patch will introduce a .drained_begin() function that needs to call virtio_queue_aio_detach_host_notifier(). .drained_begin() functions cannot call aio_poll() to wait synchronously for the BH. It is possible for a .drained_poll() callback to asynchronously wait for the BH, but that is more complex than necessary here. Move the virtqueue processing out to the callers of virtio_queue_aio_detach_host_notifier() so that the function can be called from any thread. This is in preparation for the next patch. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20230516190238.8401-17-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> |
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| .. | ||
| meson.build | ||
| trace-events | ||
| trace.h | ||
| virtio-blk.c | ||
| virtio-blk.h | ||
| xen-block.c | ||
| xen-block.h | ||