This patch enables sending CVQ state load commands in parallel at device startup by following steps:
* Refactor vhost_vdpa_net_load_cmd() to iterate through the control commands shadow buffers. This allows different CVQ state load commands to use their own unique buffers. * Delay the polling and checking of buffers until either the SVQ is full or control commands shadow buffers are full. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1578 Signed-off-by: Hawkins Jiawei <yin31...@gmail.com> --- net/vhost-vdpa.c | 157 +++++++++++++++++++++++++++++------------------ 1 file changed, 96 insertions(+), 61 deletions(-) diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c index 795c9c1fd2..1ebb58f7f6 100644 --- a/net/vhost-vdpa.c +++ b/net/vhost-vdpa.c @@ -633,6 +633,26 @@ static uint16_t vhost_vdpa_net_svq_available_slots(VhostVDPAState *s) return vhost_svq_available_slots(svq); } +/* + * Poll SVQ for multiple pending control commands and check the device's ack. + * + * Caller should hold the BQL when invoking this function. + */ +static ssize_t vhost_vdpa_net_svq_flush(VhostVDPAState *s, + size_t cmds_in_flight) +{ + vhost_vdpa_net_svq_poll(s, cmds_in_flight); + + /* Device should and must use only one byte ack each control command */ + assert(cmds_in_flight < vhost_vdpa_net_cvq_cmd_page_len()); + for (int i = 0; i < cmds_in_flight; ++i) { + if (s->status[i] != VIRTIO_NET_OK) { + return -EIO; + } + } + return 0; +} + static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, void **out_cursor, void **in_cursor, uint8_t class, uint8_t cmd, const struct iovec *data_sg, @@ -642,19 +662,41 @@ static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, void **out_cursor, .class = class, .cmd = cmd, }; - size_t data_size = iov_size(data_sg, data_num); + size_t data_size = iov_size(data_sg, data_num), + left_bytes = vhost_vdpa_net_cvq_cmd_page_len() - + (*out_cursor - s->cvq_cmd_out_buffer); /* Buffers for the device */ struct iovec out = { - .iov_base = *out_cursor, .iov_len = sizeof(ctrl) + data_size, }; struct iovec in = { - .iov_base = *in_cursor, .iov_len = sizeof(*s->status), }; ssize_t r; - assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl)); + if (sizeof(ctrl) > left_bytes || data_size > left_bytes - sizeof(ctrl) || + vhost_vdpa_net_svq_available_slots(s) < 2) { + /* + * It is time to flush all pending control commands if SVQ is full + * or control commands shadow buffers are full. + * + * We can poll here since we've had BQL from the time + * we sent the descriptor. + */ + r = vhost_vdpa_net_svq_flush(s, *in_cursor - (void *)s->status); + if (unlikely(r < 0)) { + return r; + } + + *out_cursor = s->cvq_cmd_out_buffer; + *in_cursor = s->status; + left_bytes = vhost_vdpa_net_cvq_cmd_page_len(); + } + + out.iov_base = *out_cursor; + in.iov_base = *in_cursor; + + assert(data_size <= left_bytes - sizeof(ctrl)); /* Each CVQ command has one out descriptor and one in descriptor */ assert(vhost_vdpa_net_svq_available_slots(s) >= 2); @@ -670,11 +712,11 @@ static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, void **out_cursor, return r; } - /* - * We can poll here since we've had BQL from the time - * we sent the descriptor. - */ - return vhost_vdpa_net_svq_poll(s, 1); + /* iterate the cursors */ + *out_cursor += out.iov_len; + *in_cursor += in.iov_len; + + return 0; } static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n, @@ -685,15 +727,12 @@ static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n, .iov_base = (void *)n->mac, .iov_len = sizeof(n->mac), }; - ssize_t dev_written = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, - VIRTIO_NET_CTRL_MAC, - VIRTIO_NET_CTRL_MAC_ADDR_SET, - &data, 1); - if (unlikely(dev_written < 0)) { - return dev_written; - } - if (*s->status != VIRTIO_NET_OK) { - return -EIO; + ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, + VIRTIO_NET_CTRL_MAC, + VIRTIO_NET_CTRL_MAC_ADDR_SET, + &data, 1); + if (unlikely(r < 0)) { + return r; } } @@ -738,15 +777,12 @@ static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n, .iov_len = mul_macs_size, }, }; - ssize_t dev_written = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, + ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, VIRTIO_NET_CTRL_MAC, VIRTIO_NET_CTRL_MAC_TABLE_SET, data, ARRAY_SIZE(data)); - if (unlikely(dev_written < 0)) { - return dev_written; - } - if (*s->status != VIRTIO_NET_OK) { - return -EIO; + if (unlikely(r < 0)) { + return r; } return 0; @@ -757,7 +793,7 @@ static int vhost_vdpa_net_load_mq(VhostVDPAState *s, void **out_cursor, void **in_cursor) { struct virtio_net_ctrl_mq mq; - ssize_t dev_written; + ssize_t r; if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_MQ)) { return 0; @@ -768,15 +804,12 @@ static int vhost_vdpa_net_load_mq(VhostVDPAState *s, .iov_base = &mq, .iov_len = sizeof(mq), }; - dev_written = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, - VIRTIO_NET_CTRL_MQ, - VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, - &data, 1); - if (unlikely(dev_written < 0)) { - return dev_written; - } - if (*s->status != VIRTIO_NET_OK) { - return -EIO; + r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, + VIRTIO_NET_CTRL_MQ, + VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, + &data, 1); + if (unlikely(r < 0)) { + return r; } return 0; @@ -787,7 +820,7 @@ static int vhost_vdpa_net_load_offloads(VhostVDPAState *s, void **out_cursor, void **in_cursor) { uint64_t offloads; - ssize_t dev_written; + ssize_t r; if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) { @@ -815,15 +848,12 @@ static int vhost_vdpa_net_load_offloads(VhostVDPAState *s, .iov_base = &offloads, .iov_len = sizeof(offloads), }; - dev_written = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, - VIRTIO_NET_CTRL_GUEST_OFFLOADS, - VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, - &data, 1); - if (unlikely(dev_written < 0)) { - return dev_written; - } - if (*s->status != VIRTIO_NET_OK) { - return -EIO; + r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, + VIRTIO_NET_CTRL_GUEST_OFFLOADS, + VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, + &data, 1); + if (unlikely(r < 0)) { + return r; } return 0; @@ -838,15 +868,12 @@ static int vhost_vdpa_net_load_rx_mode(VhostVDPAState *s, .iov_base = &on, .iov_len = sizeof(on), }; - ssize_t dev_written; + ssize_t r; - dev_written = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, - VIRTIO_NET_CTRL_RX, cmd, &data, 1); - if (unlikely(dev_written < 0)) { - return dev_written; - } - if (*s->status != VIRTIO_NET_OK) { - return -EIO; + r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, + VIRTIO_NET_CTRL_RX, cmd, &data, 1); + if (unlikely(r < 0)) { + return r; } return 0; @@ -1001,15 +1028,12 @@ static int vhost_vdpa_net_load_single_vlan(VhostVDPAState *s, .iov_base = &vid, .iov_len = sizeof(vid), }; - ssize_t dev_written = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, - VIRTIO_NET_CTRL_VLAN, - VIRTIO_NET_CTRL_VLAN_ADD, - &data, 1); - if (unlikely(dev_written < 0)) { - return dev_written; - } - if (unlikely(*s->status != VIRTIO_NET_OK)) { - return -EIO; + ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor, + VIRTIO_NET_CTRL_VLAN, + VIRTIO_NET_CTRL_VLAN_ADD, + &data, 1); + if (unlikely(r < 0)) { + return r; } return 0; @@ -1078,6 +1102,17 @@ static int vhost_vdpa_net_load(NetClientState *nc) return r; } + /* + * We need to poll and check all pending device's used buffers. + * + * We can poll here since we've had BQL from the time + * we sent the descriptor. + */ + r = vhost_vdpa_net_svq_flush(s, in_cursor - (void *)s->status); + if (unlikely(r)) { + return r; + } + return 0; } -- 2.25.1
