ethernet-input optimizations
Change-Id: I4ec7750ef58363bd8966a16a2baeec6db18b7e9e
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/plugins/dpdk/device/init.c b/src/plugins/dpdk/device/init.c
index e8718f7..c2e4d22 100644
--- a/src/plugins/dpdk/device/init.c
+++ b/src/plugins/dpdk/device/init.c
@@ -1824,10 +1824,10 @@
vec_add1 (dm->conf->eal_init_args, (u8 *) "vnet");
/* Default vlib_buffer_t flags, DISABLES tcp/udp checksumming... */
- dm->buffer_flags_template =
- (VLIB_BUFFER_TOTAL_LENGTH_VALID | VLIB_BUFFER_EXT_HDR_VALID
- | VNET_BUFFER_F_L4_CHECKSUM_COMPUTED |
- VNET_BUFFER_F_L4_CHECKSUM_CORRECT | VNET_BUFFER_F_L2_HDR_OFFSET_VALID);
+ dm->buffer_flags_template = (VLIB_BUFFER_TOTAL_LENGTH_VALID |
+ VLIB_BUFFER_EXT_HDR_VALID |
+ VNET_BUFFER_F_L4_CHECKSUM_COMPUTED |
+ VNET_BUFFER_F_L4_CHECKSUM_CORRECT);
dm->stat_poll_interval = DPDK_STATS_POLL_INTERVAL;
dm->link_state_poll_interval = DPDK_LINK_POLL_INTERVAL;
diff --git a/src/plugins/dpdk/device/node.c b/src/plugins/dpdk/device/node.c
index 6a3c1c9..a0144f7 100644
--- a/src/plugins/dpdk/device/node.c
+++ b/src/plugins/dpdk/device/node.c
@@ -34,46 +34,13 @@
#undef _
};
-STATIC_ASSERT (VNET_DEVICE_INPUT_NEXT_IP4_INPUT - 1 ==
- VNET_DEVICE_INPUT_NEXT_IP4_NCS_INPUT,
- "IP4_INPUT must follow IP4_NCS_INPUT");
-
-enum
-{
- DPDK_RX_F_CKSUM_GOOD = 7,
- DPDK_RX_F_CKSUM_BAD = 4,
- DPDK_RX_F_FDIR = 2,
-};
-
-/* currently we are just copying bit positions from DPDK, but that
- might change in future, in case we start to be interested in something
- stored in upper bytes. Currently we store only lower byte for perf reasons */
-STATIC_ASSERT (1 << DPDK_RX_F_CKSUM_GOOD == PKT_RX_IP_CKSUM_GOOD, "");
-STATIC_ASSERT (1 << DPDK_RX_F_CKSUM_BAD == PKT_RX_IP_CKSUM_BAD, "");
-STATIC_ASSERT (1 << DPDK_RX_F_FDIR == PKT_RX_FDIR, "");
-STATIC_ASSERT ((PKT_RX_IP_CKSUM_GOOD | PKT_RX_IP_CKSUM_BAD | PKT_RX_FDIR) <
+/* make sure all flags we need are stored in lower 8 bits */
+STATIC_ASSERT ((PKT_RX_IP_CKSUM_BAD | PKT_RX_FDIR) <
256, "dpdk flags not un lower byte, fix needed");
-always_inline u32
-dpdk_rx_next (vlib_node_runtime_t * node, u16 etype, u8 flags)
-{
- if (PREDICT_TRUE (etype == clib_host_to_net_u16 (ETHERNET_TYPE_IP4)))
- {
- /* keep it branchless */
- u32 is_good = (flags >> DPDK_RX_F_CKSUM_GOOD) & 1;
- return VNET_DEVICE_INPUT_NEXT_IP4_INPUT - is_good;
- }
- else if (PREDICT_TRUE (etype == clib_host_to_net_u16 (ETHERNET_TYPE_IP6)))
- return VNET_DEVICE_INPUT_NEXT_IP6_INPUT;
- else if (PREDICT_TRUE (etype == clib_host_to_net_u16 (ETHERNET_TYPE_MPLS)))
- return VNET_DEVICE_INPUT_NEXT_MPLS_INPUT;
- else
- return VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT;
-}
-
static_always_inline uword
dpdk_process_subseq_segs (vlib_main_t * vm, vlib_buffer_t * b,
- struct rte_mbuf * mb, vlib_buffer_free_list_t * fl)
+ struct rte_mbuf *mb, vlib_buffer_free_list_t * fl)
{
u8 nb_seg = 1;
struct rte_mbuf *mb_seg = 0;
@@ -140,20 +107,6 @@
CLIB_PREFETCH (b, CLIB_CACHE_LINE_BYTES, LOAD);
}
-static_always_inline void
-dpdk_prefetch_buffer_data_x4 (struct rte_mbuf *mb[])
-{
- vlib_buffer_t *b;
- b = vlib_buffer_from_rte_mbuf (mb[0]);
- CLIB_PREFETCH (b->data, CLIB_CACHE_LINE_BYTES, LOAD);
- b = vlib_buffer_from_rte_mbuf (mb[1]);
- CLIB_PREFETCH (b->data, CLIB_CACHE_LINE_BYTES, LOAD);
- b = vlib_buffer_from_rte_mbuf (mb[2]);
- CLIB_PREFETCH (b->data, CLIB_CACHE_LINE_BYTES, LOAD);
- b = vlib_buffer_from_rte_mbuf (mb[3]);
- CLIB_PREFETCH (b->data, CLIB_CACHE_LINE_BYTES, LOAD);
-}
-
/** \brief Main DPDK input node
@node dpdk-input
@@ -217,20 +170,16 @@
vlib_buffer_free_list_t *fl;
struct rte_mbuf **mb = ptd->mbufs;
uword n_bytes = 0;
- i16 off;
u8 *flags, or_flags = 0;
- u16 *next;
- fl = vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
+ if (maybe_multiseg)
+ fl = vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
mb = ptd->mbufs;
flags = ptd->flags;
- next = ptd->next;
while (n_left >= 8)
{
- CLIB_PREFETCH (mb + 8, CLIB_CACHE_LINE_BYTES, LOAD);
-
dpdk_prefetch_buffer_x4 (mb + 4);
b[0] = vlib_buffer_from_rte_mbuf (mb[0]);
@@ -245,42 +194,17 @@
or_flags |= dpdk_ol_flags_extract (mb, flags, 4);
flags += 4;
- /* we temporary store relative offset of ethertype into next[x]
- so we can prefetch and get it faster later */
+ b[0]->current_data = mb[0]->data_off - RTE_PKTMBUF_HEADROOM;
+ n_bytes += b[0]->current_length = mb[0]->data_len;
- off = mb[0]->data_off;
- next[0] = off + STRUCT_OFFSET_OF (ethernet_header_t, type);
- off -= RTE_PKTMBUF_HEADROOM;
- vnet_buffer (b[0])->l2_hdr_offset = off;
- b[0]->current_data = off;
+ b[1]->current_data = mb[1]->data_off - RTE_PKTMBUF_HEADROOM;
+ n_bytes += b[1]->current_length = mb[1]->data_len;
- off = mb[1]->data_off;
- next[1] = off + STRUCT_OFFSET_OF (ethernet_header_t, type);
- off -= RTE_PKTMBUF_HEADROOM;
- vnet_buffer (b[1])->l2_hdr_offset = off;
- b[1]->current_data = off;
+ b[2]->current_data = mb[2]->data_off - RTE_PKTMBUF_HEADROOM;
+ n_bytes += b[2]->current_length = mb[2]->data_len;
- off = mb[2]->data_off;
- next[2] = off + STRUCT_OFFSET_OF (ethernet_header_t, type);
- off -= RTE_PKTMBUF_HEADROOM;
- vnet_buffer (b[2])->l2_hdr_offset = off;
- b[2]->current_data = off;
-
- off = mb[3]->data_off;
- next[3] = off + STRUCT_OFFSET_OF (ethernet_header_t, type);
- off -= RTE_PKTMBUF_HEADROOM;
- vnet_buffer (b[3])->l2_hdr_offset = off;
- b[3]->current_data = off;
-
- b[0]->current_length = mb[0]->data_len;
- b[1]->current_length = mb[1]->data_len;
- b[2]->current_length = mb[2]->data_len;
- b[3]->current_length = mb[3]->data_len;
-
- n_bytes += mb[0]->data_len;
- n_bytes += mb[1]->data_len;
- n_bytes += mb[2]->data_len;
- n_bytes += mb[3]->data_len;
+ b[3]->current_data = mb[3]->data_off - RTE_PKTMBUF_HEADROOM;
+ n_bytes += b[3]->current_length = mb[3]->data_len;
if (maybe_multiseg)
{
@@ -298,7 +222,6 @@
/* next */
mb += 4;
n_left -= 4;
- next += 4;
}
while (n_left)
@@ -308,13 +231,9 @@
or_flags |= dpdk_ol_flags_extract (mb, flags, 1);
flags += 1;
- off = mb[0]->data_off;
- next[0] = off + STRUCT_OFFSET_OF (ethernet_header_t, type);
- off -= RTE_PKTMBUF_HEADROOM;
- vnet_buffer (b[0])->l2_hdr_offset = off;
- b[0]->current_data = off;
- b[0]->current_length = mb[0]->data_len;
- n_bytes += mb[0]->data_len;
+ b[0]->current_data = mb[0]->data_off - RTE_PKTMBUF_HEADROOM;
+ n_bytes += b[0]->current_length = mb[0]->data_len;
+
if (maybe_multiseg)
n_bytes += dpdk_process_subseq_segs (vm, b[0], mb[0], fl);
VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b[0]);
@@ -322,7 +241,6 @@
/* next */
mb += 1;
n_left -= 1;
- next += 1;
}
*or_flagsp = or_flags;
@@ -330,72 +248,6 @@
}
static_always_inline void
-dpdk_set_next_from_etype (vlib_main_t * vm, vlib_node_runtime_t * node,
- dpdk_per_thread_data_t * ptd, uword n_rx_packets)
-{
- vlib_buffer_t *b[4];
- i16 adv[4];
- u16 etype[4];
- struct rte_mbuf **mb = ptd->mbufs;
- u8 *flags = ptd->flags;
- u16 *next = ptd->next;
- u32 n_left = n_rx_packets;
-
- while (n_left >= 12)
- {
- dpdk_prefetch_buffer_data_x4 (mb + 8);
- dpdk_prefetch_buffer_x4 (mb + 8);
-
- b[0] = vlib_buffer_from_rte_mbuf (mb[0]);
- b[1] = vlib_buffer_from_rte_mbuf (mb[1]);
- b[2] = vlib_buffer_from_rte_mbuf (mb[2]);
- b[3] = vlib_buffer_from_rte_mbuf (mb[3]);
- etype[0] = *(u16 *) ((u8 *) mb[0] + next[0] + sizeof (vlib_buffer_t));
- etype[1] = *(u16 *) ((u8 *) mb[1] + next[1] + sizeof (vlib_buffer_t));
- etype[2] = *(u16 *) ((u8 *) mb[2] + next[2] + sizeof (vlib_buffer_t));
- etype[3] = *(u16 *) ((u8 *) mb[3] + next[3] + sizeof (vlib_buffer_t));
- next[0] = dpdk_rx_next (node, etype[0], flags[0]);
- next[1] = dpdk_rx_next (node, etype[1], flags[1]);
- next[2] = dpdk_rx_next (node, etype[2], flags[2]);
- next[3] = dpdk_rx_next (node, etype[3], flags[3]);
- adv[0] = device_input_next_node_advance[next[0]];
- adv[1] = device_input_next_node_advance[next[1]];
- adv[2] = device_input_next_node_advance[next[2]];
- adv[3] = device_input_next_node_advance[next[3]];
- b[0]->current_data += adv[0];
- b[1]->current_data += adv[1];
- b[2]->current_data += adv[2];
- b[3]->current_data += adv[3];
- b[0]->current_length -= adv[0];
- b[1]->current_length -= adv[1];
- b[2]->current_length -= adv[2];
- b[3]->current_length -= adv[3];
-
- /* next */
- next += 4;
- mb += 4;
- n_left -= 4;
- flags += 4;
- }
-
- while (n_left)
- {
- b[0] = vlib_buffer_from_rte_mbuf (mb[0]);
- next[0] = *(u16 *) ((u8 *) mb[0] + next[0] + sizeof (vlib_buffer_t));
- next[0] = dpdk_rx_next (node, next[0], flags[0]);
- adv[0] = device_input_next_node_advance[next[0]];
- b[0]->current_data += adv[0];
- b[0]->current_length -= adv[0];
-
- /* next */
- next += 1;
- mb += 1;
- n_left -= 1;
- flags += 1;
- }
-}
-
-static_always_inline void
dpdk_process_flow_offload (dpdk_device_t * xd, dpdk_per_thread_data_t * ptd,
uword n_rx_packets)
{
@@ -406,7 +258,7 @@
/* TODO prefetch and quad-loop */
for (n = 0; n < n_rx_packets; n++)
{
- if ((ptd->flags[n] & (1 << DPDK_RX_F_FDIR)) == 0)
+ if ((ptd->flags[n] & (1 << PKT_RX_FDIR)) == 0)
continue;
fle = pool_elt_at_index (xd->flow_lookup_entries,
@@ -439,10 +291,10 @@
u32 next_index = VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT;
struct rte_mbuf **mb;
vlib_buffer_t *b0;
- int known_next = 0;
u16 *next;
u8 or_flags;
u32 n;
+ int single_next = 0;
dpdk_per_thread_data_t *ptd = vec_elt_at_index (dm->per_thread_data,
thread_index);
@@ -472,77 +324,96 @@
/* as DPDK is allocating empty buffers from mempool provided before interface
start for each queue, it is safe to store this in the template */
bt->buffer_pool_index = xd->buffer_pool_for_queue[queue_id];
+ vnet_buffer (bt)->feature_arc_index = 0;
+ bt->current_config_index = 0;
/* receive burst of packets from DPDK PMD */
if (PREDICT_FALSE (xd->per_interface_next_index != ~0))
- {
- known_next = 1;
- next_index = xd->per_interface_next_index;
- }
+ next_index = xd->per_interface_next_index;
/* as all packets belong to the same interface feature arc lookup
can be don once and result stored in the buffer template */
if (PREDICT_FALSE (vnet_device_input_have_features (xd->sw_if_index)))
- {
- vnet_feature_start_device_input_x1 (xd->sw_if_index, &next_index, bt);
- known_next = 1;
- }
+ vnet_feature_start_device_input_x1 (xd->sw_if_index, &next_index, bt);
if (xd->flags & DPDK_DEVICE_FLAG_MAYBE_MULTISEG)
n_rx_bytes = dpdk_process_rx_burst (vm, ptd, n_rx_packets, 1, &or_flags);
else
n_rx_bytes = dpdk_process_rx_burst (vm, ptd, n_rx_packets, 0, &or_flags);
- if (PREDICT_FALSE (known_next))
+ if (PREDICT_FALSE (or_flags & (1 << PKT_RX_FDIR)))
{
+ /* some packets will need to go to different next nodes */
for (n = 0; n < n_rx_packets; n++)
ptd->next[n] = next_index;
- vnet_buffer (bt)->feature_arc_index = 0;
- bt->current_config_index = 0;
+ /* flow offload - process if rx flow offload enabled and at least one
+ packet is marked */
+ if (PREDICT_FALSE ((xd->flags & DPDK_DEVICE_FLAG_RX_FLOW_OFFLOAD) &&
+ (or_flags & (1 << PKT_RX_FDIR))))
+ dpdk_process_flow_offload (xd, ptd, n_rx_packets);
+
+ /* enqueue buffers to the next node */
+ vlib_get_buffer_indices_with_offset (vm, (void **) ptd->mbufs,
+ ptd->buffers, n_rx_packets,
+ sizeof (struct rte_mbuf));
+
+ vlib_buffer_enqueue_to_next (vm, node, ptd->buffers, ptd->next,
+ n_rx_packets);
}
else
- dpdk_set_next_from_etype (vm, node, ptd, n_rx_packets);
+ {
+ u32 *to_next, n_left_to_next;
- /* flow offload - process if rx flow offload enabled and at least one packet
- is marked */
- if (PREDICT_FALSE ((xd->flags & DPDK_DEVICE_FLAG_RX_FLOW_OFFLOAD) &&
- (or_flags & (1 << DPDK_RX_F_FDIR))))
- dpdk_process_flow_offload (xd, ptd, n_rx_packets);
+ vlib_get_new_next_frame (vm, node, next_index, to_next, n_left_to_next);
+ vlib_get_buffer_indices_with_offset (vm, (void **) ptd->mbufs, to_next,
+ n_rx_packets,
+ sizeof (struct rte_mbuf));
- /* is at least one packet marked as ip4 checksum bad? */
- if (PREDICT_FALSE (or_flags & (1 << DPDK_RX_F_CKSUM_BAD)))
- for (n = 0; n < n_rx_packets; n++)
- {
- if ((ptd->flags[n] & (1 << DPDK_RX_F_CKSUM_BAD)) == 0)
- continue;
- if (ptd->next[n] != VNET_DEVICE_INPUT_NEXT_IP4_INPUT)
- continue;
+ if (PREDICT_TRUE (next_index == VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT))
+ {
+ vlib_next_frame_t *nf;
+ vlib_frame_t *f;
+ ethernet_input_frame_t *ef;
+ nf = vlib_node_runtime_get_next_frame (vm, node, next_index);
+ f = vlib_get_frame (vm, nf->frame_index);
+ f->flags = ETH_INPUT_FRAME_F_SINGLE_SW_IF_IDX;
- b0 = vlib_buffer_from_rte_mbuf (ptd->mbufs[n]);
- b0->error = node->errors[DPDK_ERROR_IP_CHECKSUM_ERROR];
- ptd->next[n] = VNET_DEVICE_INPUT_NEXT_DROP;
- }
+ ef = vlib_frame_scalar_args (f);
+ ef->sw_if_index = xd->sw_if_index;
+ ef->hw_if_index = xd->hw_if_index;
- /* enqueue buffers to the next node */
- vlib_get_buffer_indices_with_offset (vm, (void **) ptd->mbufs, ptd->buffers,
- n_rx_packets,
- sizeof (struct rte_mbuf));
-
- vlib_buffer_enqueue_to_next (vm, node, ptd->buffers, ptd->next,
- n_rx_packets);
+ /* if PMD supports ip4 checksum check and there are no packets
+ marked as ip4 checksum bad we can notify ethernet input so it
+ can send pacets to ip4-input-no-checksum node */
+ if (xd->flags & DPDK_DEVICE_FLAG_RX_IP4_CKSUM &&
+ (or_flags & (1 << PKT_RX_IP_CKSUM_BAD)) == 0)
+ f->flags |= ETH_INPUT_FRAME_F_IP4_CKSUM_OK;
+ }
+ n_left_to_next -= n_rx_packets;
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ single_next = 1;
+ }
/* packet trace if enabled */
if (PREDICT_FALSE ((n_trace = vlib_get_trace_count (vm, node))))
{
+ if (single_next)
+ vlib_get_buffer_indices_with_offset (vm, (void **) ptd->mbufs,
+ ptd->buffers, n_rx_packets,
+ sizeof (struct rte_mbuf));
+
n_left = n_rx_packets;
buffers = ptd->buffers;
mb = ptd->mbufs;
next = ptd->next;
+
while (n_trace && n_left)
{
b0 = vlib_get_buffer (vm, buffers[0]);
- vlib_trace_buffer (vm, node, next[0], b0, /* follow_chain */ 0);
+ if (single_next == 0)
+ next_index = next[0];
+ vlib_trace_buffer (vm, node, next_index, b0, /* follow_chain */ 0);
dpdk_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof t0[0]);
t0->queue_index = queue_id;
diff --git a/src/vnet/ethernet/ethernet.h b/src/vnet/ethernet/ethernet.h
index ece7aa5..7435599 100644
--- a/src/vnet/ethernet/ethernet.h
+++ b/src/vnet/ethernet/ethernet.h
@@ -45,6 +45,20 @@
#include <vnet/pg/pg.h>
#include <vnet/feature/feature.h>
+/* ethernet-input frame flags and scalar data */
+
+/* all packets in frame share same sw_if_index */
+#define ETH_INPUT_FRAME_F_SINGLE_SW_IF_IDX (1 << 0)
+
+/* all ip4 packets in frame have correct ip4 checksum */
+#define ETH_INPUT_FRAME_F_IP4_CKSUM_OK (1 << 1)
+
+typedef struct
+{
+ u32 sw_if_index;
+ u32 hw_if_index;
+} ethernet_input_frame_t;
+
always_inline u64
ethernet_mac_address_u64 (const u8 * a)
{
@@ -154,6 +168,7 @@
/* Ethernet interface instance. */
typedef struct ethernet_interface
{
+ u32 flags;
/* Accept all packets (promiscuous mode). */
#define ETHERNET_INTERFACE_FLAG_ACCEPT_ALL (1 << 0)
diff --git a/src/vnet/ethernet/interface.c b/src/vnet/ethernet/interface.c
index c66fa82..f1e6785 100644
--- a/src/vnet/ethernet/interface.c
+++ b/src/vnet/ethernet/interface.c
@@ -379,6 +379,7 @@
ASSERT (hi->hw_class_index == ethernet_hw_interface_class.index);
ei = pool_elt_at_index (em->interfaces, hi->hw_instance);
+ ei->flags = flags;
if (ei->flag_change)
return ei->flag_change (vnm, hi, flags);
return (u32) ~ 0;
diff --git a/src/vnet/ethernet/node.c b/src/vnet/ethernet/node.c
index 53d5b4e..c39c6d7 100755
--- a/src/vnet/ethernet/node.c
+++ b/src/vnet/ethernet/node.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Copyright (c) 2018 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
@@ -49,7 +49,9 @@
#define foreach_ethernet_input_next \
_ (PUNT, "error-punt") \
_ (DROP, "error-drop") \
- _ (LLC, "llc-input")
+ _ (LLC, "llc-input") \
+ _ (IP4_INPUT, "ip4-input") \
+ _ (IP4_INPUT_NCS, "ip4-input-no-checksum")
typedef enum
{
@@ -62,6 +64,8 @@
typedef struct
{
u8 packet_data[32];
+ u16 frame_flags;
+ ethernet_input_frame_t frame_data;
} ethernet_input_trace_t;
static u8 *
@@ -70,7 +74,16 @@
CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
ethernet_input_trace_t *t = va_arg (*va, ethernet_input_trace_t *);
+ u32 indent = format_get_indent (s);
+ if (t->frame_flags)
+ {
+ s = format (s, "frame: flags 0x%x", t->frame_flags);
+ if (t->frame_flags & ETH_INPUT_FRAME_F_SINGLE_SW_IF_IDX)
+ s = format (s, ", hw-if-index %u, sw-if-index %u",
+ t->frame_data.hw_if_index, t->frame_data.sw_if_index);
+ s = format (s, "\n%U", format_white_space, indent);
+ }
s = format (s, "%U", format_ethernet_header, t->packet_data);
return s;
@@ -289,16 +302,401 @@
}
}
-static_always_inline uword
+typedef enum
+{
+ ETYPE_ID_UNKNOWN = 0,
+ ETYPE_ID_IP4,
+ ETYPE_ID_IP6,
+ ETYPE_ID_MPLS,
+ ETYPE_N_IDS,
+} etype_id_t;
+
+static_always_inline void
+eth_input_advance_and_flags (vlib_main_t * vm, u32 * from, u32 n_left,
+ i16 advance, u32 and_flags, u32 or_flags)
+{
+ vlib_buffer_t *b[8];
+ while (n_left >= 8)
+ {
+ vlib_get_buffers (vm, from, b, 8);
+ vlib_buffer_advance (b[0], advance);
+ vlib_buffer_advance (b[1], advance);
+ vlib_buffer_advance (b[2], advance);
+ vlib_buffer_advance (b[3], advance);
+ vlib_buffer_advance (b[4], advance);
+ vlib_buffer_advance (b[5], advance);
+ vlib_buffer_advance (b[6], advance);
+ vlib_buffer_advance (b[7], advance);
+ b[0]->flags = (b[0]->flags & and_flags) | or_flags;
+ b[1]->flags = (b[1]->flags & and_flags) | or_flags;
+ b[2]->flags = (b[2]->flags & and_flags) | or_flags;
+ b[3]->flags = (b[3]->flags & and_flags) | or_flags;
+ b[4]->flags = (b[4]->flags & and_flags) | or_flags;
+ b[5]->flags = (b[5]->flags & and_flags) | or_flags;
+ b[6]->flags = (b[6]->flags & and_flags) | or_flags;
+ b[7]->flags = (b[7]->flags & and_flags) | or_flags;
+
+ n_left -= 8;
+ from += 8;
+ }
+ while (n_left)
+ {
+ vlib_get_buffers (vm, from, b, 1);
+ vlib_buffer_advance (b[0], advance);
+ b[0]->flags = (b[0]->flags & and_flags) | or_flags;
+
+ n_left -= 1;
+ from += 1;
+ }
+}
+
+typedef struct
+{
+ u16 etypes[VLIB_FRAME_SIZE];
+ u32 bufs_by_etype[ETYPE_N_IDS][VLIB_FRAME_SIZE];
+ u16 n_bufs_by_etype[ETYPE_N_IDS];
+} eth_input_data_t;
+
+/* following vector code relies on following assumptions */
+STATIC_ASSERT_OFFSET_OF (vlib_buffer_t, current_data, 0);
+STATIC_ASSERT_OFFSET_OF (vlib_buffer_t, current_length, 2);
+STATIC_ASSERT_OFFSET_OF (vlib_buffer_t, flags, 4);
+STATIC_ASSERT (STRUCT_OFFSET_OF (vnet_buffer_opaque_t, l2_hdr_offset) ==
+ STRUCT_OFFSET_OF (vnet_buffer_opaque_t, l3_hdr_offset) - 2,
+ "l3_hdr_offset must follow l2_hdr_offset");
+
+static_always_inline void
+eth_input_adv_and_flags_x4 (vlib_buffer_t ** b, i16 adv, u32 flags, int is_l3)
+{
+#ifdef CLIB_HAVE_VEC256
+ /* to reduce number of small loads/stores we are loading first 64 bits
+ of each buffer metadata into 256-bit register so we can advance
+ current_data, current_length and flags.
+ Observed saving of this code is ~2 clocks per packet */
+ u64x4 r, radv;
+
+ /* vector if signed 16 bit integers used in signed vector add operation
+ to advnce current_data and current_length */
+ u32x8 flags4 = { 0, flags, 0, flags, 0, flags, 0, flags };
+ i16x16 adv4 = {
+ adv, -adv, 0, 0, adv, -adv, 0, 0,
+ adv, -adv, 0, 0, adv, -adv, 0, 0
+ };
+
+ /* load 4 x 64 bits */
+ r = u64x4_gather (b[0], b[1], b[2], b[3]);
+
+ /* set flags */
+ r |= (u64x4) flags4;
+
+ /* advance buffer */
+ radv = (u64x4) ((i16x16) r + adv4);
+
+ /* write 4 x 64 bits */
+ u64x4_scatter (is_l3 ? radv : r, b[0], b[1], b[2], b[3]);
+
+ /* use old current_data as l2_hdr_offset and new current_data as
+ l3_hdr_offset */
+ r = (u64x4) u16x16_blend (r, radv << 16, 0xaa);
+
+ /* store both l2_hdr_offset and l3_hdr_offset in single store operation */
+ u32x8_scatter_one ((u32x8) r, 0, &vnet_buffer (b[0])->l2_hdr_offset);
+ u32x8_scatter_one ((u32x8) r, 2, &vnet_buffer (b[1])->l2_hdr_offset);
+ u32x8_scatter_one ((u32x8) r, 4, &vnet_buffer (b[2])->l2_hdr_offset);
+ u32x8_scatter_one ((u32x8) r, 6, &vnet_buffer (b[3])->l2_hdr_offset);
+
+ ASSERT (b[0]->current_data == vnet_buffer (b[0])->l3_hdr_offset);
+ ASSERT (b[1]->current_data == vnet_buffer (b[1])->l3_hdr_offset);
+ ASSERT (b[2]->current_data == vnet_buffer (b[2])->l3_hdr_offset);
+ ASSERT (b[3]->current_data == vnet_buffer (b[3])->l3_hdr_offset);
+
+ ASSERT (b[0]->current_data - vnet_buffer (b[0])->l2_hdr_offset == adv);
+ ASSERT (b[1]->current_data - vnet_buffer (b[1])->l2_hdr_offset == adv);
+ ASSERT (b[2]->current_data - vnet_buffer (b[2])->l2_hdr_offset == adv);
+ ASSERT (b[3]->current_data - vnet_buffer (b[3])->l2_hdr_offset == adv);
+
+#else
+ vnet_buffer (b[0])->l2_hdr_offset = b[0]->current_data;
+ vnet_buffer (b[1])->l2_hdr_offset = b[1]->current_data;
+ vnet_buffer (b[2])->l2_hdr_offset = b[2]->current_data;
+ vnet_buffer (b[3])->l2_hdr_offset = b[3]->current_data;
+ vnet_buffer (b[0])->l3_hdr_offset = b[0]->current_data + adv;
+ vnet_buffer (b[1])->l3_hdr_offset = b[1]->current_data + adv;
+ vnet_buffer (b[2])->l3_hdr_offset = b[2]->current_data + adv;
+ vnet_buffer (b[3])->l3_hdr_offset = b[3]->current_data + adv;
+
+ if (is_l3)
+ {
+ vlib_buffer_advance (b[0], adv);
+ vlib_buffer_advance (b[1], adv);
+ vlib_buffer_advance (b[2], adv);
+ vlib_buffer_advance (b[3], adv);
+ }
+
+ b[0]->flags |= flags;
+ b[1]->flags |= flags;
+ b[2]->flags |= flags;
+ b[3]->flags |= flags;
+#endif
+
+ if (!is_l3)
+ {
+ vnet_buffer (b[0])->l2.l2_len = adv;
+ vnet_buffer (b[1])->l2.l2_len = adv;
+ vnet_buffer (b[2])->l2.l2_len = adv;
+ vnet_buffer (b[3])->l2.l2_len = adv;
+ }
+}
+
+static_always_inline void
+eth_input_adv_and_flags_x1 (vlib_buffer_t ** b, i16 adv, u32 flags, int is_l3)
+{
+ vnet_buffer (b[0])->l2_hdr_offset = b[0]->current_data;
+ vnet_buffer (b[0])->l3_hdr_offset = b[0]->current_data + adv;
+
+ if (is_l3)
+ vlib_buffer_advance (b[0], adv);
+ b[0]->flags |= flags;
+ if (!is_l3)
+ vnet_buffer (b[0])->l2.l2_len = adv;
+}
+
+static_always_inline void
+eth_input_process_frame (vlib_main_t * vm, u32 * from, u16 * etype,
+ u32 n_left, int is_l3)
+{
+ vlib_buffer_t *b[16];
+ ethernet_header_t *e;
+ int adv = sizeof (ethernet_header_t);
+
+ u32 flags = VNET_BUFFER_F_L2_HDR_OFFSET_VALID |
+ VNET_BUFFER_F_L3_HDR_OFFSET_VALID;
+
+ while (n_left >= 16)
+ {
+ vlib_buffer_t **ph = b + 12, **pd = b + 8;
+ vlib_get_buffers (vm, from, b, 4);
+ vlib_get_buffers (vm, from + 8, b + 8, 8);
+
+ vlib_prefetch_buffer_header (ph[0], LOAD);
+ vlib_prefetch_buffer_data (pd[0], LOAD);
+ e = vlib_buffer_get_current (b[0]);
+ etype[0] = e->type;
+
+ vlib_prefetch_buffer_header (ph[1], LOAD);
+ vlib_prefetch_buffer_data (pd[1], LOAD);
+ e = vlib_buffer_get_current (b[1]);
+ etype[1] = e->type;
+
+ vlib_prefetch_buffer_header (ph[2], LOAD);
+ vlib_prefetch_buffer_data (pd[2], LOAD);
+ e = vlib_buffer_get_current (b[2]);
+ etype[2] = e->type;
+
+ vlib_prefetch_buffer_header (ph[3], LOAD);
+ vlib_prefetch_buffer_data (pd[3], LOAD);
+ e = vlib_buffer_get_current (b[3]);
+ etype[3] = e->type;
+
+ eth_input_adv_and_flags_x4 (b, adv, flags, is_l3);
+
+ /* next */
+ n_left -= 4;
+ etype += 4;
+ from += 4;
+ }
+ while (n_left >= 4)
+ {
+ vlib_get_buffers (vm, from, b, 4);
+
+ e = vlib_buffer_get_current (b[0]);
+ etype[0] = e->type;
+
+ e = vlib_buffer_get_current (b[1]);
+ etype[1] = e->type;
+
+ e = vlib_buffer_get_current (b[2]);
+ etype[2] = e->type;
+
+ e = vlib_buffer_get_current (b[3]);
+ etype[3] = e->type;
+
+ eth_input_adv_and_flags_x4 (b, adv, flags, is_l3);
+
+ /* next */
+ n_left -= 4;
+ etype += 4;
+ from += 4;
+ }
+ while (n_left)
+ {
+ vlib_get_buffers (vm, from, b, 1);
+
+ e = vlib_buffer_get_current (b[0]);
+ etype[0] = e->type;
+
+ eth_input_adv_and_flags_x1 (b, adv, flags, is_l3);
+
+ /* next */
+ n_left -= 1;
+ etype += 1;
+ from += 1;
+ }
+}
+
+static_always_inline void
+eth_input_sort (vlib_main_t * vm, u32 * from, u32 n_packets,
+ eth_input_data_t * d)
+{
+ u16 *etype = d->etypes;
+ i32 n_left = n_packets;
+
+#if defined (CLIB_HAVE_VEC256)
+ u16x16 e16;
+ u16x16 et16_ip4 = u16x16_splat (clib_host_to_net_u16 (ETHERNET_TYPE_IP4));
+ u16x16 et16_ip6 = u16x16_splat (clib_host_to_net_u16 (ETHERNET_TYPE_IP6));
+ u16x16 et16_mpls = u16x16_splat (clib_host_to_net_u16 (ETHERNET_TYPE_MPLS));
+ u16x16 id16_ip4 = u16x16_splat (ETYPE_ID_IP4);
+ u16x16 id16_ip6 = u16x16_splat (ETYPE_ID_IP6);
+ u16x16 id16_mpls = u16x16_splat (ETYPE_ID_MPLS);
+
+ while (n_left > 0)
+ {
+ u16x16 r = { 0 };
+ e16 = u16x16_load_unaligned (etype);
+ r += (e16 == et16_ip4) & id16_ip4;
+ r += (e16 == et16_ip6) & id16_ip6;
+ r += (e16 == et16_mpls) & id16_mpls;
+ u16x16_store_unaligned (r, etype);
+ etype += 16;
+ n_left -= 16;
+ }
+#elif defined (CLIB_HAVE_VEC128)
+ u16x8 e8;
+ u16x8 et8_ip4 = u16x8_splat (clib_host_to_net_u16 (ETHERNET_TYPE_IP4));
+ u16x8 et8_ip6 = u16x8_splat (clib_host_to_net_u16 (ETHERNET_TYPE_IP6));
+ u16x8 et8_mpls = u16x8_splat (clib_host_to_net_u16 (ETHERNET_TYPE_MPLS));
+ u16x8 id8_ip4 = u16x8_splat (ETYPE_ID_IP4);
+ u16x8 id8_ip6 = u16x8_splat (ETYPE_ID_IP6);
+ u16x8 id8_mpls = u16x8_splat (ETYPE_ID_MPLS);
+
+ while (n_left > 0)
+ {
+ u16x8 r = { 0 };
+ e8 = u16x8_load_unaligned (etype);
+ r += (e8 == et8_ip4) & id8_ip4;
+ r += (e8 == et8_ip6) & id8_ip6;
+ r += (e8 == et8_mpls) & id8_mpls;
+ u16x8_store_unaligned (r, etype);
+ etype += 8;
+ n_left -= 8;
+ }
+#else
+ while (n_left)
+ {
+ if (etype[0] == ETHERNET_TYPE_IP4)
+ etype[0] = ETYPE_ID_IP4;
+ else if (etype[0] == ETHERNET_TYPE_IP6)
+ etype[0] = ETYPE_ID_IP6;
+ else if (etype[0] == ETHERNET_TYPE_MPLS)
+ etype[0] = ETYPE_ID_MPLS;
+ else
+ etype[0] = ETYPE_ID_UNKNOWN;
+
+ etype += 1;
+ n_left -= 1;
+ }
+#endif
+
+ etype = d->etypes;
+ n_left = n_packets;
+
+ clib_memset_u16 (d->n_bufs_by_etype, 0, ETYPE_N_IDS);
+ while (n_left)
+ {
+ u16 x, y;
+ x = etype[0];
+ y = d->n_bufs_by_etype[x];
+
+#ifdef CLIB_HAVE_VEC256
+ if (n_left >= 16 && u16x16_is_all_equal (u16x16_load_unaligned (etype),
+ etype[0]))
+ {
+ clib_memcpy_fast (&d->bufs_by_etype[x][y], from, 16 * sizeof (u32));
+ d->n_bufs_by_etype[x] += 16;
+
+ /* next */
+ n_left -= 16;
+ etype += 16;
+ from += 16;
+ continue;
+ }
+#endif
+#ifdef CLIB_HAVE_VEC128
+ if (n_left >= 8 && u16x8_is_all_equal (u16x8_load_unaligned (etype),
+ etype[0]))
+ {
+ clib_memcpy_fast (&d->bufs_by_etype[x][y], from, 8 * sizeof (u32));
+ d->n_bufs_by_etype[x] += 8;
+
+ /* next */
+ n_left -= 8;
+ etype += 8;
+ from += 8;
+ continue;
+ }
+#endif
+ d->bufs_by_etype[x][y] = from[0];
+ d->n_bufs_by_etype[x]++;
+
+ /* next */
+ n_left -= 1;
+ etype += 1;
+ from += 1;
+ }
+}
+
+static_always_inline void
+ethernet_input_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
+ vlib_frame_t * from_frame)
+{
+ u32 *from, n_left;
+ if ((node->flags & VLIB_NODE_FLAG_TRACE) == 0)
+ return;
+
+ from = vlib_frame_vector_args (from_frame);
+ n_left = from_frame->n_vectors;
+
+ while (n_left)
+ {
+ ethernet_input_trace_t *t0;
+ vlib_buffer_t *b0 = vlib_get_buffer (vm, from[0]);
+
+ if (b0->flags & VLIB_BUFFER_IS_TRACED)
+ {
+ t0 = vlib_add_trace (vm, node, b0, sizeof (ethernet_input_trace_t));
+ clib_memcpy_fast (t0->packet_data, b0->data + b0->current_data,
+ sizeof (t0->packet_data));
+ t0->frame_flags = from_frame->flags;
+ clib_memcpy_fast (&t0->frame_data,
+ vlib_frame_scalar_args (from_frame),
+ sizeof (ethernet_input_frame_t));
+ }
+ from += 1;
+ n_left -= 1;
+ }
+}
+
+static_always_inline void
ethernet_input_inline (vlib_main_t * vm,
vlib_node_runtime_t * node,
- vlib_frame_t * from_frame,
+ u32 * from, u32 n_packets,
ethernet_input_variant_t variant)
{
vnet_main_t *vnm = vnet_get_main ();
ethernet_main_t *em = ðernet_main;
vlib_node_runtime_t *error_node;
- u32 n_left_from, next_index, *from, *to_next;
+ u32 n_left_from, next_index, *to_next;
u32 stats_sw_if_index, stats_n_packets, stats_n_bytes;
u32 thread_index = vm->thread_index;
u32 cached_sw_if_index = ~0;
@@ -310,15 +708,7 @@
else
error_node = node;
- from = vlib_frame_vector_args (from_frame);
- n_left_from = from_frame->n_vectors;
-
- if (node->flags & VLIB_NODE_FLAG_TRACE)
- vlib_trace_frame_buffers_only (vm, node,
- from,
- n_left_from,
- sizeof (from[0]),
- sizeof (ethernet_input_trace_t));
+ n_left_from = n_packets;
next_index = node->cached_next_index;
stats_sw_if_index = node->runtime_data[0];
@@ -764,32 +1154,136 @@
thread_index, stats_sw_if_index, stats_n_packets, stats_n_bytes);
node->runtime_data[0] = stats_sw_if_index;
}
+}
- return from_frame->n_vectors;
+static_always_inline void
+eth_input_enqueue_untagged (vlib_main_t * vm, vlib_node_runtime_t * node,
+ eth_input_data_t * d, int ip4_cksum_ok, int is_l3)
+{
+ ethernet_main_t *em = ðernet_main;
+ etype_id_t id;
+ u32 next_index;
+
+ id = ETYPE_ID_IP4;
+ if (d->n_bufs_by_etype[id])
+ {
+ if (is_l3)
+ {
+ next_index = em->l3_next.input_next_ip4;
+ if (next_index == ETHERNET_INPUT_NEXT_IP4_INPUT && ip4_cksum_ok)
+ next_index = ETHERNET_INPUT_NEXT_IP4_INPUT_NCS;
+ }
+ else
+ next_index = em->l2_next;
+
+ vlib_buffer_enqueue_to_single_next (vm, node, d->bufs_by_etype[id],
+ next_index, d->n_bufs_by_etype[id]);
+ }
+
+ id = ETYPE_ID_IP6;
+ if (d->n_bufs_by_etype[id])
+ {
+ next_index = is_l3 ? em->l3_next.input_next_ip6 : em->l2_next;
+ vlib_buffer_enqueue_to_single_next (vm, node, d->bufs_by_etype[id],
+ next_index, d->n_bufs_by_etype[id]);
+ }
+
+ id = ETYPE_ID_MPLS;
+ if (d->n_bufs_by_etype[id])
+ {
+ next_index = is_l3 ? em->l3_next.input_next_mpls : em->l2_next;
+ vlib_buffer_enqueue_to_single_next (vm, node, d->bufs_by_etype[id],
+ next_index, d->n_bufs_by_etype[id]);
+ }
+
+ id = ETYPE_ID_UNKNOWN;
+ if (d->n_bufs_by_etype[id])
+ {
+ /* in case of l3 interfaces, we already advanced buffer so we need to
+ roll back */
+ if (is_l3)
+ eth_input_advance_and_flags (vm, d->bufs_by_etype[id],
+ d->n_bufs_by_etype[id],
+ -(i16) sizeof (ethernet_header_t),
+ ~VNET_BUFFER_F_L3_HDR_OFFSET_VALID, 0);
+ ethernet_input_inline (vm, node, d->bufs_by_etype[id],
+ d->n_bufs_by_etype[id],
+ ETHERNET_INPUT_VARIANT_ETHERNET);
+ }
}
VLIB_NODE_FN (ethernet_input_node) (vlib_main_t * vm,
vlib_node_runtime_t * node,
- vlib_frame_t * from_frame)
+ vlib_frame_t * frame)
{
- return ethernet_input_inline (vm, node, from_frame,
- ETHERNET_INPUT_VARIANT_ETHERNET);
+ vnet_main_t *vnm = vnet_get_main ();
+ ethernet_main_t *em = ðernet_main;
+ u32 *from = vlib_frame_vector_args (frame);
+ u32 n_packets = frame->n_vectors;
+
+ ethernet_input_trace (vm, node, frame);
+
+ if (frame->flags & ETH_INPUT_FRAME_F_SINGLE_SW_IF_IDX)
+ {
+ eth_input_data_t data, *d = &data;
+ ethernet_input_frame_t *ef = vlib_frame_scalar_args (frame);
+ vnet_hw_interface_t *hi = vnet_get_hw_interface (vnm, ef->hw_if_index);
+ main_intf_t *intf0 = vec_elt_at_index (em->main_intfs, hi->hw_if_index);
+ subint_config_t *subint0 = &intf0->untagged_subint;
+ int ip4_cksum_ok = (frame->flags & ETH_INPUT_FRAME_F_IP4_CKSUM_OK) != 0;
+
+ if (subint0->flags & SUBINT_CONFIG_L2)
+ {
+ /* untagged packets are treated as L2 */
+ eth_input_process_frame (vm, from, d->etypes, n_packets, 0);
+ eth_input_sort (vm, from, n_packets, d);
+ eth_input_enqueue_untagged (vm, node, d, ip4_cksum_ok, 0);
+ }
+ else
+ {
+ ethernet_interface_t *ei;
+ ei = pool_elt_at_index (em->interfaces, hi->hw_instance);
+
+ /* currently only slowpath deals with dmac check */
+ if (ei->flags & ETHERNET_INTERFACE_FLAG_ACCEPT_ALL)
+ goto slowpath;
+
+ /* untagged packets are treated as L3 */
+ eth_input_process_frame (vm, from, d->etypes, n_packets, 1);
+ eth_input_sort (vm, from, n_packets, d);
+ eth_input_enqueue_untagged (vm, node, d, ip4_cksum_ok, 1);
+ }
+ return n_packets;
+ }
+
+slowpath:
+ ethernet_input_inline (vm, node, from, n_packets,
+ ETHERNET_INPUT_VARIANT_ETHERNET);
+ return n_packets;
}
VLIB_NODE_FN (ethernet_input_type_node) (vlib_main_t * vm,
vlib_node_runtime_t * node,
vlib_frame_t * from_frame)
{
- return ethernet_input_inline (vm, node, from_frame,
- ETHERNET_INPUT_VARIANT_ETHERNET_TYPE);
+ u32 *from = vlib_frame_vector_args (from_frame);
+ u32 n_packets = from_frame->n_vectors;
+ ethernet_input_trace (vm, node, from_frame);
+ ethernet_input_inline (vm, node, from, n_packets,
+ ETHERNET_INPUT_VARIANT_ETHERNET_TYPE);
+ return n_packets;
}
VLIB_NODE_FN (ethernet_input_not_l2_node) (vlib_main_t * vm,
vlib_node_runtime_t * node,
vlib_frame_t * from_frame)
{
- return ethernet_input_inline (vm, node, from_frame,
- ETHERNET_INPUT_VARIANT_NOT_L2);
+ u32 *from = vlib_frame_vector_args (from_frame);
+ u32 n_packets = from_frame->n_vectors;
+ ethernet_input_trace (vm, node, from_frame);
+ ethernet_input_inline (vm, node, from, n_packets,
+ ETHERNET_INPUT_VARIANT_NOT_L2);
+ return n_packets;
}
@@ -1159,6 +1653,7 @@
.name = "ethernet-input",
/* Takes a vector of packets. */
.vector_size = sizeof (u32),
+ .scalar_size = sizeof (ethernet_input_frame_t),
.n_errors = ETHERNET_N_ERROR,
.error_strings = ethernet_error_strings,
.n_next_nodes = ETHERNET_INPUT_N_NEXT,
diff --git a/src/vnet/pg/input.c b/src/vnet/pg/input.c
index 8b46688..ee6aad4 100644
--- a/src/vnet/pg/input.c
+++ b/src/vnet/pg/input.c
@@ -40,6 +40,7 @@
#include <vlib/vlib.h>
#include <vnet/pg/pg.h>
#include <vnet/vnet.h>
+#include <vnet/ethernet/ethernet.h>
#include <vnet/feature/feature.h>
#include <vnet/devices/devices.h>
@@ -1496,7 +1497,24 @@
{
u32 *head, *start, *end;
- vlib_get_next_frame (vm, node, next_index, to_next, n_left);
+ if (PREDICT_TRUE (next_index == VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT))
+ {
+ vlib_next_frame_t *nf;
+ vlib_frame_t *f;
+ ethernet_input_frame_t *ef;
+ pg_interface_t *pi;
+ vlib_get_new_next_frame (vm, node, next_index, to_next, n_left);
+ nf = vlib_node_runtime_get_next_frame (vm, node, next_index);
+ f = vlib_get_frame (vm, nf->frame_index);
+ f->flags = ETH_INPUT_FRAME_F_SINGLE_SW_IF_IDX;
+
+ ef = vlib_frame_scalar_args (f);
+ pi = pool_elt_at_index (pg->interfaces, s->pg_if_index);
+ ef->sw_if_index = pi->sw_if_index;
+ ef->hw_if_index = pi->hw_if_index;
+ }
+ else
+ vlib_get_next_frame (vm, node, next_index, to_next, n_left);
n_this_frame = n_packets_to_generate;
if (n_this_frame > n_left)