On Thu, Jul 07, 2022 at 10:44:08AM +0800, Guo Zhi wrote: > Prior implementation only use one descriptor for each io event, which > does't test code of descriptor chain. More importantly, one descriptor > will not use indirect feature even indirect feature is specified. Use > random length scatterlists here to test descriptor chain. > > Signed-off-by: Guo Zhi <[email protected]> > --- > tools/virtio/virtio_test.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c > index 1ecd64271..363695b33 100644 > --- a/tools/virtio/virtio_test.c > +++ b/tools/virtio/virtio_test.c > @@ -20,6 +20,7 @@ > #include "../../drivers/vhost/test.h" > > #define RANDOM_BATCH -1 > +#define MAX_SG_FRAGS 8UL > #define ALIGN 4096 > #define RINGSIZE 256 > #define TEST_BUF_NUM 0x100000 > @@ -172,7 +173,8 @@ static void wait_for_interrupt(struct vdev_info *dev) > static void run_test(struct vdev_info *dev, struct vq_info *vq, > bool delayed, int batch, int reset_n, int bufs) > { > - struct scatterlist sl; > + struct scatterlist sg[MAX_SG_FRAGS]; > + int sg_size = 0; > long started = 0, completed = 0, next_reset = reset_n; > long completed_before, started_before; > int r, test = 1; > @@ -197,8 +199,11 @@ static void run_test(struct vdev_info *dev, struct > vq_info *vq, > > while (started < bufs && > (started - completed) < batch) { > - sg_init_one(&sl, dev->buf, dev->buf_size); > - r = virtqueue_add_outbuf(vq->vq, &sl, 1, > + sg_size = random() % (MAX_SG_FRAGS - 1) + 1; > + sg_init_table(sg, sg_size); > + for (int i = 0; i < sg_size; ++i) > + sg_set_buf(&sg[i], dev->buf + i, 0x1); > + r = virtqueue_add_outbuf(vq->vq, sg, sg_size, > dev->buf + started, > GFP_ATOMIC); > if (unlikely(r != 0)) {
random on data path is pretty expensive. I would suggest get an array size from user (and maybe a seed?) and pregenerate some numbers, then reuse. > -- > 2.17.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
