/*
*------------------------------------------------------------------
* 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:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*------------------------------------------------------------------
*/
#include <poll.h>
#include <vlib/vlib.h>
#include <vlib/unix/unix.h>
#include <vlib/pci/pci.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/devices/devices.h>
#include <vnet/interface/rx_queue_funcs.h>
#include "af_xdp.h"
#define foreach_af_xdp_input_error \
_(POLL_REQUIRED, "poll required") \
_(POLL_FAILURES, "poll failures")
typedef enum
{
#define _(f,s) AF_XDP_INPUT_ERROR_##f,
foreach_af_xdp_input_error
#undef _
AF_XDP_INPUT_N_ERROR,
} af_xdp_input_error_t;
static __clib_unused char *af_xdp_input_error_strings[] = {
#define _(n,s) s,
foreach_af_xdp_input_error
#undef _
};
static_always_inline void
af_xdp_device_input_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
u32 n_left, const u32 * bi, u32 next_index,
u32 hw_if_index)
{
u32 n_trace = vlib_get_trace_count (vm, node);
if (PREDICT_TRUE (0 == n_trace))
return;
while (n_trace && n_left)
{
vlib_buffer_t *b = vlib_get_buffer (vm, bi[0]);
if (PREDICT_TRUE
(vlib_trace_buffer (vm, node, next_index, b, /* follow_chain */ 0)))
{
af_xdp_input_trace_t *tr =
vlib_add_trace (vm, node, b, sizeof (*tr));
tr->next_index = next_index;
tr->hw_if_index = hw_if_index;
n_trace--;
}
n_left--;
bi++;
}
vlib_set_trace_count (vm, node, n_trace);
}
static_always_inline void
af_xdp_device_input_refill_db (vlib_main_t * vm,
const vlib_node_runtime_t * node,
af_xdp_device_t * ad, af_xdp_rxq_t * rxq,
const u32 n_alloc)
{
int ret;
xsk_ring_prod__submit (&rxq->fq, n_alloc);
if (!xsk_ring_prod__needs_wakeup (&rxq->fq))
return;
vlib_error_count (vm, node->node_index, AF_XDP_INPUT_ERROR_POLL_REQUIRED,
1);
struct pollfd fd = {.fd = rxq->xsk_fd,.events = POLLIN };
ret = poll (&fd, 1, 0);
if (PREDICT_TRUE (ret >= 0))
return;
/* something bad is happening */
vlib_error_count (vm, node->node_index, AF_XDP_INPUT_ERROR_POLL_FAILURES,
1);
af_xdp_device_error (ad, "poll() failed");
}
static_always_inline void
af_xdp_device_input_refill (vlib_main_t * vm,
const vlib_node_runtime_t * node,
af_xdp_device_t * ad, af_xdp_rxq_t * rxq,
const int copy)
{
__u64 *fill;
const u32 size = rxq->fq.size;
const u32 mask = size - 1;
u32 bis[VLIB_FRAME_SIZE], *bi = bis;
u32 n_alloc, n, n_wrap;
u32 idx = 0;
ASSERT (mask == rxq->fq.mask);
/* do not enqueue more packet than ring space */
n_alloc = xsk_prod_nb_free (&rxq->fq, 16);
/* do not bother to allocate if too small */
if (n_alloc < 16)
return;
n_alloc = clib_min (n_alloc, ARRAY_LEN (bis));
n_alloc = vlib_buffer_alloc_from_pool (vm, bis, n_alloc, ad->pool);
n = xsk_ring_prod__reserve (&rxq->fq, n_alloc, &idx);
ASSERT (n == n_alloc);
fill = xsk_ring_prod__fill_addr (&rxq->fq, idx);
n = clib_min (n_alloc, size - (idx & mask));
n_wrap = n_alloc - n;
/*
* Note about headroom: for some reasons, there seem to be a discrepency
* between 0-copy and copy mode:
* - 0-copy: XDP_PACKET_HEADROOM will be added to the user headroom
* - copy: nothing is added to the user headroom
* We privileged 0-copy and set headroom to 0. As XDP_PACKET_HEADROOM ==
* sizeof(vlib_buffer_t), data will correctly point to vlib_buffer_t->data.
* In copy mode, we have to add sizeof(vlib_buffer_t) to desc offset during
* refill.
*/
STATIC_ASSERT (sizeof (vlib_buffer_t) == XDP_PACKET_HEADROOM, "wrong size");
#define bi2addr(bi) \
(((bi) << CLIB_LOG2_CACHE_LINE_BYTES) + (copy ? sizeof(vlib_buffer_t) : 0))
wrap_around:
while (n >= 8)
{
#ifdef CLIB_HAVE_VEC256
u64x4 b0 = u64x4_from_u32x4 (*(u32x4u *) (bi + 0));
u64x4 b1 = u64x4_from_u32x4 (*(u32x4u *) (bi + 4));
*(u64x4u *) (fill + 0) = bi2addr (b0);
*(u64x4u *) (fill + 4) = bi2addr (b1);
#else
fill[0] = bi2addr (bi[0]);
fill[1] = bi2addr (bi[1]);
fill[2] = bi2addr (bi[2]);
fill[3] = bi2addr (bi[3]);
fill[4] = bi2addr (bi[4]);
fill[5] = bi2addr (bi[5]);
fill[6] = bi2addr (bi[6]);
fill[7] = bi2addr (bi[7]);
#endif
fill += 8;
bi += 8;
n -= 8;
}
while (n >= 1)
{
fill[0] = bi2addr (bi[0]);
fill += 1;
bi += 1;
n -= 1;
}
if (n_wrap)
{
fill = xsk_ring_prod__fill_addr (&rxq->fq, 0);
n = n_wrap;
n_wrap = 0;
goto wrap_around;
}
af_xdp_device_input_refill_db (vm, node, ad, rxq, n_alloc);
}
static_always_inline void
af_xdp_device_input_ethernet (vlib_main_t * vm, vlib_node_runtime_t * node,
const u32 next_index, const u32 sw_if_index,
const u32 hw_if_index)
{
vlib_next_frame_t *nf;
vlib_frame_t *f;
ethernet_input_frame_t *ef;
if (PREDICT_FALSE (VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT != next_index))
return;
nf =
vlib_node_runtime_get_next_frame (vm, node,
VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT);
f = vlib_get_frame (vm, nf->frame);
f->flags = ETH_INPUT_FRAME_F_SINGLE_SW_IF_IDX;
ef = vlib_frame_scalar_args (f);
ef->sw_if_index = sw_if_index;
ef->hw_if_index = hw_if_index;
}
static_always_inline u32
af_xdp_device_input_bufs (vlib_main_t * vm, const af_xdp_device_t * ad,
af_xdp_rxq_t * rxq, u32 * bis, const u32 n_rx,
vlib_buffer_t * bt, u32 idx, const int copy)
{
vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
u16 lens[VLIB_FRAME_SIZE], *len = lens;
const u32 mask = rxq->rx.mask;
u32 n = n_rx, *bi = bis, bytes = 0;
#define addr2bi(addr) \
(((addr) - (copy ? sizeof(vlib_buffer_t) : 0)) >> CLIB_LOG2_CACHE_LINE_BYTES)
while (n >= 1)
{
const struct xdp_desc *desc = xsk_ring_cons__rx_desc (&rxq->rx, idx);
bi[0] = addr2bi (xsk_umem__extract_addr (desc->addr));
ASSERT (vlib_buffer_is_known (vm, bi[0]) ==
VLIB_BUFFER_KNOWN_ALLOCATED);
len[0] = desc->len;
idx = (idx + 1) & mask;
bi += 1;
len += 1;
n -= 1;
}
vlib_get_buffers (vm, bis, bufs, n_rx);
n = n_rx;
len = lens;
while (n >= 8)
{
vlib_prefetch_buffer_header (b[4], LOAD);
vlib_buffer_copy_template (b[0], bt);
bytes += b[0]->current_length = len[0];
vlib_prefetch_buffer_header (b[5], LOAD);
vlib_buffer_copy_template (b[1], bt);
bytes += b[1]->current_length = len[1];
vlib_prefetch_buffer_header (b[6], LOAD);
vlib_buffer_copy_template (b[2], bt);
bytes += b[2]->current_length = len[2];
vlib_prefetch_buffer_header (b[7], LOAD);
vlib_buffer_copy_template (b[3], bt);
bytes += b[3]->current_length = len[3];
b += 4;
len += 4;
n -= 4;
}
while (n >= 1)
{
vlib_buffer_copy_template (b[0], bt);
bytes += b[0]->current_length = len[0];
b += 1;
len += 1;
n -= 1;
}
xsk_ring_cons__release (&rxq->rx, n_rx);
return bytes;
}
static_always_inline uword
af_xdp_device_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
vlib_frame_t * frame, af_xdp_device_t * ad,
u16 qid, const int copy)
{
vnet_main_t *vnm = vnet_get_main ();
af_xdp_rxq_t *rxq = vec_elt_at_index (ad->rxqs, qid);
vlib_buffer_t bt;
u32 next_index, *to_next, n_left_to_next;
u32 n_rx_packets, n_rx_bytes;
u32 idx;
n_rx_packets = xsk_ring_cons__peek (&rxq->rx, VLIB_FRAME_SIZE, &idx);
if (PREDICT_FALSE (0 == n_rx_packets))
goto refill;
vlib_buffer_copy_template (&bt, ad->buffer_template);
next_index = ad->per_interface_next_index;
if (PREDICT_FALSE (vnet_device_input_have_features (ad->sw_if_index)))
vnet_feature_start_device_input_x1 (ad->sw_if_index, &next_index, &bt);
vlib_get_new_next_frame (vm, node, next_index, to_next, n_left_to_next);
n_rx_bytes =
af_xdp_device_input_bufs (vm, ad, rxq, to_next, n_rx_packets, &bt, idx,
copy);
af_xdp_device_input_ethernet (vm, node, next_index, ad->sw_if_index,
ad->hw_if_index);
vlib_put_next_frame (vm, node, next_index, n_left_to_next - n_rx_packets);
af_xdp_device_input_trace (vm, node, n_rx_packets, to_next, next_index,
ad->hw_if_index);
vlib_increment_combined_counter
(vnm->interface_main.combined_sw_if_counters +
VNET_INTERFACE_COUNTER_RX, vm->thread_index,
ad->hw_if_index, n_rx_packets, n_rx_bytes);
refill:
af_xdp_device_input_refill (vm, node, ad, rxq, copy);
return n_rx_packets;
}
VLIB_NODE_FN (af_xdp_input_node) (vlib_main_t * vm,
vlib_node_runtime_t * node,
vlib_frame_t * frame)
{
u32 n_rx = 0;
af_xdp_main_t *am = &af_xdp_main;
vnet_hw_if_rxq_poll_vector_t *p,
*pv = vnet_hw_if_get_rxq_poll_vector (vm, node);
vec_foreach (p, pv)
{
af_xdp_device_t *ad = vec_elt_at_index (am->devices, p->dev_instance);
if ((ad->flags & AF_XDP_DEVICE_F_ADMIN_UP) == 0)
continue;
if (PREDICT_TRUE (ad->flags & AF_XDP_DEVICE_F_ZEROCOPY))
n_rx += af_xdp_device_input_inline (vm, node, frame, ad, p->queue_id,
/* copy */ 0);
else
n_rx += af_xdp_device_input_inline (vm, node, frame, ad, p->queue_id,
/* copy */ 1);
}
return n_rx;
}
/* *INDENT-OFF* */
VLIB_REGISTER_NODE (af_xdp_input_node) = {
.name = "af_xdp-input",
.sibling_of = "device-input",
.format_trace = format_af_xdp_input_trace,
.type = VLIB_NODE_TYPE_INPUT,
.state = VLIB_NODE_STATE_DISABLED,
.n_errors = AF_XDP_INPUT_N_ERROR,
.error_strings = af_xdp_input_error_strings,
.flags = VLIB_NODE_FLAG_TRACE_SUPPORTED,
};
/* *INDENT-ON* */
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/