virtio_ring: virtqueue_add_sgs, to add multiple sgs.

2013-03-20T05:13:29Z

virtio_scsi can really use this, to avoid the current hack of copying the whole sg array. Some other things get slightly neater, too. This causes a slowdown in virtqueue_add_buf(), which is implemented as a wrapper. This is addressed in the next patches. for i in `seq 50`; do /usr/bin/time -f 'Wall time:%e' ./vringh_test --indirect --eventidx --parallel --fast-vringh; done 2>&1 | stats --trim-outliers: Before: Using CPUS 0 and 3 Guest: notified 0, pinged 39009-39063(39062) Host: notified 39009-39063(39062), pinged 0 Wall time:1.700000-1.950000(1.723542) After: Using CPUS 0 and 3 Guest: notified 0, pinged 39062-39063(39063) Host: notified 39062-39063(39063), pinged 0 Wall time:1.760000-2.220000(1.789167) Signed-off-by: Rusty Russell Reviewed-by: Wanlong Gao Reviewed-by: Asias He

tools/virtio: separate headers more.

2013-03-20T03:30:42Z

This makes them a bit more like the kernel headers, so we can include more real kernel headers in our tests. In addition this means that we don't break tools/virtio with the next patch. Signed-off-by: Rusty Russell

kernel/tools/virtio/linux/scatterlist.h, branch linux-4.1.y

virtio_ring: virtqueue_add_sgs, to add multiple sgs.

tools/virtio: separate headers more.