From b977d3f7c28caee8359098be569b55e770c5c6ec Mon Sep 17 00:00:00 2001 From: Mohsin Kazmi Date: Mon, 16 Nov 2020 16:49:30 +0100 Subject: virtio: virtio: implement packed queues from virtio 1.1 Type: feature Change-Id: I12703371541298efa029903d6762b1cd1f7322ca Signed-off-by: Mohsin Kazmi --- src/vnet/devices/virtio/node.c | 216 ++++++++++++++++++++++++++++++++++++----- 1 file changed, 190 insertions(+), 26 deletions(-) (limited to 'src/vnet/devices/virtio/node.c') diff --git a/src/vnet/devices/virtio/node.c b/src/vnet/devices/virtio/node.c index 91e788e4d28..a45b52c2eab 100644 --- a/src/vnet/devices/virtio/node.c +++ b/src/vnet/devices/virtio/node.c @@ -81,9 +81,9 @@ format_virtio_input_trace (u8 * s, va_list * args) } static_always_inline void -virtio_refill_vring (vlib_main_t * vm, virtio_if_t * vif, - virtio_if_type_t type, virtio_vring_t * vring, - const int hdr_sz, u32 node_index) +virtio_refill_vring_split (vlib_main_t * vm, virtio_if_t * vif, + virtio_if_type_t type, virtio_vring_t * vring, + const int hdr_sz, u32 node_index) { u16 used, next, avail, n_slots, n_refill; u16 sz = vring->size; @@ -148,6 +148,88 @@ more: goto more; } +static_always_inline void +virtio_refill_vring_packed (vlib_main_t * vm, virtio_if_t * vif, + virtio_if_type_t type, virtio_vring_t * vring, + const int hdr_sz, u32 node_index) +{ + u16 used, next, n_slots, n_refill, flags = 0, first_desc_flags; + u16 sz = vring->size; + +more: + used = vring->desc_in_use; + + if (sz == used) + return; + + /* deliver free buffers in chunks of 64 */ + n_refill = clib_min (sz - used, 64); + + next = vring->desc_next; + first_desc_flags = vring->packed_desc[next].flags; + n_slots = + vlib_buffer_alloc_to_ring_from_pool (vm, vring->buffers, next, + sz, n_refill, + vring->buffer_pool_index); + + if (PREDICT_FALSE (n_slots != n_refill)) + { + vlib_error_count (vm, node_index, + VIRTIO_INPUT_ERROR_BUFFER_ALLOC, n_refill - n_slots); + if (n_slots == 0) + return; + } + + while (n_slots) + { + vring_packed_desc_t *d = &vring->packed_desc[next]; + vlib_buffer_t *b = vlib_get_buffer (vm, vring->buffers[next]); + /* + * current_data may not be initialized with 0 and may contain + * previous offset. Here we want to make sure, it should be 0 + * initialized. + */ + b->current_data = -hdr_sz; + memset (vlib_buffer_get_current (b), 0, hdr_sz); + d->addr = + ((type == VIRTIO_IF_TYPE_PCI) ? vlib_buffer_get_current_pa (vm, + b) : + pointer_to_uword (vlib_buffer_get_current (b))); + d->len = vlib_buffer_get_default_data_size (vm) + hdr_sz; + + if (vring->avail_wrap_counter) + flags = (VRING_DESC_F_AVAIL | VRING_DESC_F_WRITE); + else + flags = (VRING_DESC_F_USED | VRING_DESC_F_WRITE); + + d->id = next; + if (vring->desc_next == next) + first_desc_flags = flags; + else + d->flags = flags; + + next++; + if (next >= sz) + { + next = 0; + vring->avail_wrap_counter ^= 1; + } + n_slots--; + used++; + } + CLIB_MEMORY_STORE_BARRIER (); + vring->packed_desc[vring->desc_next].flags = first_desc_flags; + vring->desc_next = next; + vring->desc_in_use = used; + CLIB_MEMORY_BARRIER (); + if (vring->device_event->flags != VRING_EVENT_F_DISABLE) + { + virtio_kick (vm, vring, vif); + } + + goto more; +} + static_always_inline void virtio_needs_csum (vlib_buffer_t * b0, virtio_net_hdr_v1_t * hdr, u8 * l4_proto, u8 * l4_hdr_sz, virtio_if_type_t type) @@ -258,11 +340,51 @@ fill_gso_buffer_flags (vlib_buffer_t * b0, virtio_net_hdr_v1_t * hdr, } } +static_always_inline u16 +virtio_n_left_to_process (virtio_vring_t * vring, const int packed) +{ + if (packed) + return vring->desc_in_use; + else + return vring->used->idx - vring->last_used_idx; +} + +static_always_inline u16 +virtio_get_slot_id (virtio_vring_t * vring, const int packed, u16 last, + u16 mask) +{ + if (packed) + return vring->packed_desc[last].id; + else + return vring->used->ring[last & mask].id; +} + +static_always_inline u16 +virtio_get_len (virtio_vring_t * vring, const int packed, const int hdr_sz, + u16 last, u16 mask) +{ + if (packed) + return vring->packed_desc[last].len - hdr_sz; + else + return vring->used->ring[last & mask].len - hdr_sz; +} + +#define increment_last(last, packed, vring) \ + do { \ + last++; \ + if (packed && last >= vring->size) \ + { \ + last = 0; \ + vring->used_wrap_counter ^= 1; \ + } \ + } while (0) + static_always_inline uword virtio_device_input_gso_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame, virtio_if_t * vif, virtio_vring_t * vring, virtio_if_type_t type, - int gso_enabled, int checksum_offload_enabled) + int gso_enabled, int checksum_offload_enabled, + int packed) { vnet_main_t *vnm = vnet_get_main (); u32 thread_index = vm->thread_index; @@ -274,7 +396,7 @@ virtio_device_input_gso_inline (vlib_main_t * vm, vlib_node_runtime_t * node, u32 n_rx_bytes = 0; u16 mask = vring->size - 1; u16 last = vring->last_used_idx; - u16 n_left = vring->used->idx - last; + u16 n_left = virtio_n_left_to_process (vring, packed); vlib_buffer_t bt; if (n_left == 0) @@ -303,12 +425,24 @@ virtio_device_input_gso_inline (vlib_main_t * vm, vlib_node_runtime_t * node, while (n_left && n_left_to_next) { + if (packed) + { + vring_packed_desc_t *d = &vring->packed_desc[last]; + u16 flags = d->flags; + if ((flags & VRING_DESC_F_AVAIL) != + (vring->used_wrap_counter << 7) + || (flags & VRING_DESC_F_USED) != + (vring->used_wrap_counter << 15)) + { + n_left = 0; + break; + } + } u8 l4_proto = 0, l4_hdr_sz = 0; u16 num_buffers = 1; - vring_used_elem_t *e = &vring->used->ring[last & mask]; virtio_net_hdr_v1_t *hdr; - u16 slot = e->id; - u16 len = e->len - hdr_sz; + u16 slot = virtio_get_slot_id (vring, packed, last, mask); + u16 len = virtio_get_len (vring, packed, hdr_sz, last, mask); u32 bi0 = vring->buffers[slot]; vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0); hdr = vlib_buffer_get_current (b0); @@ -336,20 +470,22 @@ virtio_device_input_gso_inline (vlib_main_t * vm, vlib_node_runtime_t * node, b0->total_length_not_including_first_buffer = 0; while (num_buffers > 1) { - last++; - e = &vring->used->ring[last & mask]; - u32 cbi = vring->buffers[e->id]; + increment_last (last, packed, vring); + u16 cslot = virtio_get_slot_id (vring, packed, last, mask); + u16 clen = + virtio_get_len (vring, packed, hdr_sz, last, mask); + u32 cbi = vring->buffers[cslot]; cb = vlib_get_buffer (vm, cbi); /* current buffer */ - cb->current_length = e->len; + cb->current_length = clen; /* previous buffer */ pb->next_buffer = cbi; pb->flags |= VLIB_BUFFER_NEXT_PRESENT; /* first buffer */ - b0->total_length_not_including_first_buffer += e->len; + b0->total_length_not_including_first_buffer += clen; pb = cb; vring->desc_in_use--; @@ -406,7 +542,7 @@ virtio_device_input_gso_inline (vlib_main_t * vm, vlib_node_runtime_t * node, to_next += 1; n_left_to_next--; n_left--; - last++; + increment_last (last, packed, vring); /* only tun interfaces may have different next index */ if (type == VIRTIO_IF_TYPE_TUN) @@ -451,21 +587,49 @@ virtio_device_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node, clib_spinlock_unlock_if_init (&txq_vring->lockp); } - if ((vring->used->flags & VRING_USED_F_NO_NOTIFY) == 0 && - vring->last_kick_avail_idx != vring->avail->idx) - virtio_kick (vm, vring, vif); + if (vif->is_packed) + { + if (vring->device_event->flags != VRING_EVENT_F_DISABLE) + virtio_kick (vm, vring, vif); + + if (vif->gso_enabled) + rv = + virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, + 1, 1, 1); + else if (vif->csum_offload_enabled) + rv = + virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, + 0, 1, 1); + else + rv = + virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, + 0, 0, 1); - if (vif->gso_enabled) - rv = virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, - 1, 1); - else if (vif->csum_offload_enabled) - rv = virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, - 0, 1); + virtio_refill_vring_packed (vm, vif, type, vring, hdr_sz, + node->node_index); + } else - rv = virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, - 0, 0); + { + if ((vring->used->flags & VRING_USED_F_NO_NOTIFY) == 0 && + vring->last_kick_avail_idx != vring->avail->idx) + virtio_kick (vm, vring, vif); + + if (vif->gso_enabled) + rv = + virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, + 1, 1, 0); + else if (vif->csum_offload_enabled) + rv = + virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, + 0, 1, 0); + else + rv = + virtio_device_input_gso_inline (vm, node, frame, vif, vring, type, + 0, 0, 0); - virtio_refill_vring (vm, vif, type, vring, hdr_sz, node->node_index); + virtio_refill_vring_split (vm, vif, type, vring, hdr_sz, + node->node_index); + } return rv; } -- cgit 1.2.3-korg