This patch moves vhost_svq_poll() to the caller of vhost_vdpa_net_cvq_add() and introduces a helper funtion.
By making this change, next patches in this series is able to refactor vhost_vdpa_net_load_x() only to delay the polling and checking process until either the SVQ is full or control commands shadow buffers are full. Signed-off-by: Hawkins Jiawei <yin31...@gmail.com> --- v4: - always check the return value of vhost_vdpa_net_svq_poll() suggested Eugenio v3: https://lore.kernel.org/all/152177c4e7082236fba9d31d535e40f8c2984349.1689748694.git.yin31...@gmail.com/ net/vhost-vdpa.c | 53 +++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 43 insertions(+), 10 deletions(-) diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c index 116a06cc45..d9b8b3cf6c 100644 --- a/net/vhost-vdpa.c +++ b/net/vhost-vdpa.c @@ -609,15 +609,21 @@ static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, qemu_log_mask(LOG_GUEST_ERROR, "%s: No space on device queue\n", __func__); } - return r; } - /* - * We can poll here since we've had BQL from the time we sent the - * descriptor. Also, we need to take the answer before SVQ pulls by itself, - * when BQL is released - */ - return vhost_svq_poll(svq, 1); + return r; +} + +/* + * Convenience wrapper to poll SVQ for multiple control commands. + * + * Caller should hold the BQL when invoking this function, and should take + * the answer before SVQ pulls by itself when BQL is released. + */ +static ssize_t vhost_vdpa_net_svq_poll(VhostVDPAState *s, size_t cmds_in_flight) +{ + VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0); + return vhost_svq_poll(svq, cmds_in_flight); } /* Convenience wrapper to get number of available SVQ descriptors */ @@ -645,6 +651,7 @@ static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class, .iov_base = s->status, .iov_len = sizeof(*s->status), }; + ssize_t r; assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl)); /* Each CVQ command has one out descriptor and one in descriptor */ @@ -657,7 +664,16 @@ static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class, iov_to_buf(data_sg, data_num, 0, s->cvq_cmd_out_buffer + sizeof(ctrl), data_size); - return vhost_vdpa_net_cvq_add(s, &out, 1, &in, 1); + r = vhost_vdpa_net_cvq_add(s, &out, 1, &in, 1); + if (unlikely(r < 0)) { + 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); } static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n) @@ -1150,6 +1166,15 @@ static int vhost_vdpa_net_excessive_mac_filter_cvq_add(VhostVDPAState *s, if (unlikely(r < 0)) { return r; } + + /* + * We can poll here since we've had BQL from the time + * we sent the descriptor. + */ + r = vhost_vdpa_net_svq_poll(s, 1); + if (unlikely(r < sizeof(*s->status))) { + return r; + } if (*s->status != VIRTIO_NET_OK) { return sizeof(*s->status); } @@ -1269,10 +1294,18 @@ static int vhost_vdpa_net_handle_ctrl_avail(VhostShadowVirtqueue *svq, goto out; } } else { - dev_written = vhost_vdpa_net_cvq_add(s, &out, 1, &vdpa_in, 1); - if (unlikely(dev_written < 0)) { + ssize_t r; + r = vhost_vdpa_net_cvq_add(s, &out, 1, &vdpa_in, 1); + if (unlikely(r < 0)) { + dev_written = r; goto out; } + + /* + * We can poll here since we've had BQL from the time + * we sent the descriptor. + */ + dev_written = vhost_vdpa_net_svq_poll(s, 1); } if (unlikely(dev_written < sizeof(status))) { -- 2.25.1
