On 3/22/19 2:01 PM, Xiaolong Ye wrote:
Add a new PMD driver for AF_XDP which is a proposed faster version of
AF_PACKET interface in Linux. More info about AF_XDP, please refer to [1]
[2].
This is the vanilla version PMD which just uses a raw buffer registered as
the umem.
[1] https://fosdem.org/2018/schedule/event/af_xdp/
[2] https://lwn.net/Articles/745934/
Signed-off-by: Xiaolong Ye <xiaolong...@intel.com>
---
MAINTAINERS | 6 +
config/common_base | 5 +
config/common_linux | 1 +
doc/guides/nics/af_xdp.rst | 45 +
doc/guides/nics/features/af_xdp.ini | 11 +
doc/guides/nics/index.rst | 1 +
doc/guides/rel_notes/release_19_05.rst | 7 +
drivers/net/Makefile | 1 +
drivers/net/af_xdp/Makefile | 32 +
drivers/net/af_xdp/meson.build | 21 +
drivers/net/af_xdp/rte_eth_af_xdp.c | 940 ++++++++++++++++++
drivers/net/af_xdp/rte_pmd_af_xdp_version.map | 3 +
drivers/net/meson.build | 1 +
mk/rte.app.mk | 1 +
14 files changed, 1075 insertions(+)
create mode 100644 doc/guides/nics/af_xdp.rst
create mode 100644 doc/guides/nics/features/af_xdp.ini
create mode 100644 drivers/net/af_xdp/Makefile
create mode 100644 drivers/net/af_xdp/meson.build
create mode 100644 drivers/net/af_xdp/rte_eth_af_xdp.c
create mode 100644 drivers/net/af_xdp/rte_pmd_af_xdp_version.map
...
diff --git a/config/common_base b/config/common_base
index 0b09a9348..4044de205 100644
--- a/config/common_base
+++ b/config/common_base
@@ -416,6 +416,11 @@ CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_TX_FREE=n
#
CONFIG_RTE_LIBRTE_PMD_AF_PACKET=n
+#
+# Compile software PMD backed by AF_XDP sockets (Linux only)
+#
+CONFIG_RTE_LIBRTE_PMD_AF_XDP=n
+
#
# Compile link bonding PMD library
#
diff --git a/config/common_linux b/config/common_linux
index 75334273d..0b1249da0 100644
--- a/config/common_linux
+++ b/config/common_linux
@@ -19,6 +19,7 @@ CONFIG_RTE_LIBRTE_VHOST_POSTCOPY=n
CONFIG_RTE_LIBRTE_PMD_VHOST=y
CONFIG_RTE_LIBRTE_IFC_PMD=y
CONFIG_RTE_LIBRTE_PMD_AF_PACKET=y
+CONFIG_RTE_LIBRTE_PMD_AF_XDP=y
It has to be disabled by default as it requires headers from kernels
more recent than minimum kernel version supported by DPDK.
CONFIG_RTE_LIBRTE_PMD_SOFTNIC=y
CONFIG_RTE_LIBRTE_PMD_TAP=y
CONFIG_RTE_LIBRTE_AVP_PMD=y
...
diff --git a/drivers/net/af_xdp/meson.build b/drivers/net/af_xdp/meson.build
new file mode 100644
index 000000000..635e67483
--- /dev/null
+++ b/drivers/net/af_xdp/meson.build
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2018 Intel Corporation
+
+if host_machine.system() != 'linux'
+ build = false
+endif
+
+bpf_dep = dependency('libbpf', required: false)
+if bpf_dep.found()
+ build = true
+else
+ bpf_dep = cc.find_library('libbpf', required: false)
+ if bpf_dep.found() and cc.has_header('xsk.h', dependencies: bpf_dep)
+ build = true
+ pkgconfig_extra_libs += '-lbpf'
+ else
+ build = false
+ endif
+endif
I think you need to add more checks, as above does not cover
linux/if_xdp.h header IIUC.
+sources = files('rte_eth_af_xdp.c')
+ext_deps += bpf_dep
diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c
b/drivers/net/af_xdp/rte_eth_af_xdp.c
new file mode 100644
index 000000000..9f0012347
--- /dev/null
+++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
@@ -0,0 +1,940 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2019 Intel Corporation.
+ */
+
+#include <rte_mbuf.h>
+#include <rte_ethdev_driver.h>
+#include <rte_ethdev_vdev.h>
+#include <rte_malloc.h>
+#include <rte_kvargs.h>
+#include <rte_bus_vdev.h>
+#include <rte_string_fns.h>
+
+#include <linux/if_ether.h>
+#include <linux/if_xdp.h>
+#include <linux/if_link.h>
+#include <asm/barrier.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <poll.h>
+#include <bpf/bpf.h>
+#include <xsk.h>
+
+#ifndef SOL_XDP
+#define SOL_XDP 283
+#endif
+
+#ifndef AF_XDP
+#define AF_XDP 44
+#endif
+
+#ifndef PF_XDP
+#define PF_XDP AF_XDP
+#endif
+
+static int af_xdp_logtype;
+
+#define AF_XDP_LOG(level, fmt, args...) \
+ rte_log(RTE_LOG_ ## level, af_xdp_logtype, \
+ "%s(): " fmt "\n", __func__, ##args)
+
+#define ETH_AF_XDP_IFACE_ARG "iface"
+#define ETH_AF_XDP_QUEUE_IDX_ARG "queue"
+
+#define ETH_AF_XDP_FRAME_SIZE XSK_UMEM__DEFAULT_FRAME_SIZE
+#define ETH_AF_XDP_NUM_BUFFERS 4096
+#define ETH_AF_XDP_DATA_HEADROOM 0
+#define ETH_AF_XDP_DFLT_NUM_DESCS XSK_RING_CONS__DEFAULT_NUM_DESCS
+#define ETH_AF_XDP_DFLT_QUEUE_IDX 0
+
+#define ETH_AF_XDP_RX_BATCH_SIZE 32
+#define ETH_AF_XDP_TX_BATCH_SIZE 32
+
+#define ETH_AF_XDP_MAX_QUEUE_PAIRS 16
+
+struct xsk_umem_info {
+ struct xsk_ring_prod fq;
+ struct xsk_ring_cons cq;
+ struct xsk_umem *umem;
+ struct rte_ring *buf_ring;
+ void *buffer;
+};
+
+struct rx_stats {
+ uint64_t rx_pkts;
+ uint64_t rx_bytes;
+ uint64_t rx_dropped;
+};
+
+struct pkt_rx_queue {
+ struct xsk_ring_cons rx;
+ struct xsk_umem_info *umem;
+ struct xsk_socket *xsk;
+ struct rte_mempool *mb_pool;
+
+ struct rx_stats stats;
+
+ struct pkt_tx_queue *pair;
+ uint16_t queue_idx;
+};
+
+struct tx_stats {
+ uint64_t tx_pkts;
+ uint64_t err_pkts;
+ uint64_t tx_bytes;
+};
+
+struct pkt_tx_queue {
+ struct xsk_ring_prod tx;
+
+ struct tx_stats stats;
+
+ struct pkt_rx_queue *pair;
+ uint16_t queue_idx;
+};
+
+struct pmd_internals {
+ int if_index;
+ char if_name[IFNAMSIZ];
+ uint16_t queue_idx;
+ struct ether_addr eth_addr;
+ struct xsk_umem_info *umem;
+ struct rte_mempool *mb_pool_share;
+
+ struct pkt_rx_queue rx_queues[ETH_AF_XDP_MAX_QUEUE_PAIRS];
+ struct pkt_tx_queue tx_queues[ETH_AF_XDP_MAX_QUEUE_PAIRS];
+};
+
+static const char * const valid_arguments[] = {
+ ETH_AF_XDP_IFACE_ARG,
+ ETH_AF_XDP_QUEUE_IDX_ARG,
+ NULL
+};
+
+static struct rte_eth_link pmd_link = {
+ .link_speed = ETH_SPEED_NUM_10G,
+ .link_duplex = ETH_LINK_FULL_DUPLEX,
+ .link_status = ETH_LINK_DOWN,
+ .link_autoneg = ETH_LINK_AUTONEG
+};
+
+static inline int
+reserve_fill_queue(struct xsk_umem_info *umem, int reserve_size)
+{
+ struct xsk_ring_prod *fq = &umem->fq;
+ uint32_t idx;
+ void *addr = NULL;
+ int i, ret;
+
+ ret = xsk_ring_prod__reserve(fq, reserve_size, &idx);
+ if (!ret) {
You could use unlikely() here as it is called in the hot path.
+ AF_XDP_LOG(ERR, "Failed to reserve enough fq descs.\n");
+ return ret;
+ }
+
+ for (i = 0; i < reserve_size; i++) {
+ __u64 *fq_addr;
For consistency, you could either declare addr here, or fq_addr at the
top of the function.
+ if (rte_ring_dequeue(umem->buf_ring, &addr)) {
+ i--;
+ break;
+ }
+ fq_addr = xsk_ring_prod__fill_addr(fq, idx++);
+ *fq_addr = (uint64_t)addr;
+ }
+
+ xsk_ring_prod__submit(fq, i);
+
+ return 0;
+}
+
+static uint16_t
+eth_af_xdp_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
+{
+ struct pkt_rx_queue *rxq = queue;
+ struct xsk_ring_cons *rx = &rxq->rx;
+ struct xsk_umem_info *umem = rxq->umem;
+ struct xsk_ring_prod *fq = &umem->fq;
+ uint32_t idx_rx;
+ uint32_t free_thresh = fq->size >> 1;
+ struct rte_mbuf *mbufs[ETH_AF_XDP_TX_BATCH_SIZE];
+ unsigned long dropped = 0;
+ unsigned long rx_bytes = 0;
+ uint16_t count = 0;
+ int rcvd, i;
+
+ nb_pkts = RTE_MIN(nb_pkts, ETH_AF_XDP_TX_BATCH_SIZE);
+
+ rcvd = xsk_ring_cons__peek(rx, nb_pkts, &idx_rx);
+ if (rcvd == 0)
+ return 0;
+
+ if (xsk_prod_nb_free(fq, free_thresh) >= free_thresh)
+ (void)reserve_fill_queue(umem, ETH_AF_XDP_RX_BATCH_SIZE);
+
+ if (rte_pktmbuf_alloc_bulk(rxq->mb_pool, mbufs, rcvd) != 0)
unlikely()?
+ return 0;
+
+ for (i = 0; i < rcvd; i++) {
+ const struct xdp_desc *desc;
+ uint64_t addr;
+ uint32_t len;
+ void *pkt;
+
+ desc = xsk_ring_cons__rx_desc(rx, idx_rx++);
+ addr = desc->addr;
+ len = desc->len;
+ pkt = xsk_umem__get_data(rxq->umem->buffer, addr);
+
+ rte_memcpy(rte_pktmbuf_mtod(mbufs[i], void *), pkt, len);
+ rte_pktmbuf_pkt_len(mbufs[i]) = len;
+ rte_pktmbuf_data_len(mbufs[i]) = len;
+ rx_bytes += len;
+ bufs[count++] = mbufs[i];
+
+ rte_ring_enqueue(umem->buf_ring, (void *)addr);
+ }
+
+ xsk_ring_cons__release(rx, rcvd);
+
+ /* statistics */
+ rxq->stats.rx_pkts += (rcvd - dropped);
+ rxq->stats.rx_bytes += rx_bytes;
+
+ return count;
+}
+
...
+
+/* This function gets called when the current port gets stopped. */
+static void
+eth_dev_stop(struct rte_eth_dev *dev)
+{
+ dev->data->dev_link.link_status = ETH_LINK_DOWN;
+}
+
+static int
+eth_dev_configure(struct rte_eth_dev *dev __rte_unused)
Remove __rte_unused.
+{
+ /* rx/tx must be paired */
+ if (dev->data->nb_rx_queues != dev->data->nb_tx_queues)
+ return -EINVAL;
+
+ return 0;
+}
+
...
+
+static int
+xsk_configure(struct pmd_internals *internals, struct pkt_rx_queue *rxq,
+ int ring_size)
+{
+ struct xsk_socket_config cfg;
+ struct pkt_tx_queue *txq = rxq->pair;
+ int ret = 0;
+ int reserve_size;
+
+ rxq->umem = xdp_umem_configure();
+ if (rxq->umem == NULL) {
+ ret = -ENOMEM;
+ goto err;
You can return directly here as umem == NULL.
+ }
+
+ cfg.rx_size = ring_size;
+ cfg.tx_size = ring_size;
+ cfg.libbpf_flags = 0;
+ cfg.xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
+ cfg.bind_flags = 0;
+ ret = xsk_socket__create(&rxq->xsk, internals->if_name,
+ internals->queue_idx, rxq->umem->umem, &rxq->rx,
+ &txq->tx, &cfg);
+ if (ret) {
+ AF_XDP_LOG(ERR, "Failed to create xsk socket.\n");
+ goto err;
+ }
+
+ reserve_size = ETH_AF_XDP_DFLT_NUM_DESCS / 2;
+ ret = reserve_fill_queue(rxq->umem, reserve_size);
+ if (ret) {
+ AF_XDP_LOG(ERR, "Failed to reserve fill queue.\n");
+ goto err;
Shouldn't you call xsk_socket__delete(rxq->xsk) here?
+ }
+
+ return 0;
+
+err:
+ xdp_umem_destroy(rxq->umem);
+
+ return ret;
+}
+
+static void
+queue_reset(struct pmd_internals *internals, uint16_t queue_idx)
+{
+ struct pkt_rx_queue *rxq = &internals->rx_queues[queue_idx];
+ struct pkt_tx_queue *txq = rxq->pair;
+ int xsk_fd = xsk_socket__fd(rxq->xsk);
+
+ if (xsk_fd) {
+ close(xsk_fd);
+ if (internals->umem != NULL) {
Moving this condition out would work and be cleaner.
Anyway, it seems to never enter this condition as internal->umem is not
set yet when queue_reset() is called.
+ xdp_umem_destroy(internals->umem);
+ internals->umem = NULL;
+ }
+ }
+ memset(rxq, 0, sizeof(*rxq));
+ memset(txq, 0, sizeof(*txq));
+ rxq->pair = txq;
+ txq->pair = rxq;
+ rxq->queue_idx = queue_idx;
+ txq->queue_idx = queue_idx;
+}
+
+static int
+eth_rx_queue_setup(struct rte_eth_dev *dev,
+ uint16_t rx_queue_id,
+ uint16_t nb_rx_desc,
+ unsigned int socket_id __rte_unused,
+ const struct rte_eth_rxconf *rx_conf __rte_unused,
+ struct rte_mempool *mb_pool)
+{
+ struct pmd_internals *internals = dev->data->dev_private;
+ uint32_t buf_size, data_size;
+ struct pkt_rx_queue *rxq;
+ int ret;
+
+ rxq = &internals->rx_queues[rx_queue_id];
+ queue_reset(internals, rx_queue_id);
+
+ /* Now get the space available for data in the mbuf */
+ buf_size = rte_pktmbuf_data_room_size(mb_pool) -
+ RTE_PKTMBUF_HEADROOM;
+ data_size = ETH_AF_XDP_FRAME_SIZE - ETH_AF_XDP_DATA_HEADROOM;
+
+ if (data_size > buf_size) {
+ AF_XDP_LOG(ERR, "%s: %d bytes will not fit in mbuf (%d
bytes)\n",
+ dev->device->name, data_size, buf_size);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ rxq->mb_pool = mb_pool;
+
+ if (xsk_configure(internals, rxq, nb_rx_desc)) {
+ AF_XDP_LOG(ERR, "Failed to configure xdp socket\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ internals->umem = rxq->umem;
If my previous comment is wrong, i.e. internals->umem may be already set
when queue_reset() is called, then it means you might have a leak here.
+
+ dev->data->rx_queues[rx_queue_id] = rxq;
+ return 0;
+
+err:
+ queue_reset(internals, rx_queue_id);
+ return ret;
+}
+
