numam-dpdk/lib/librte_vhost/vhost.h

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/*-
* BSD LICENSE
*
* Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _VHOST_NET_CDEV_H_
#define _VHOST_NET_CDEV_H_
#include <stdint.h>
#include <stdio.h>
#include <sys/types.h>
vhost: add dequeue zero copy The basic idea of dequeue zero copy is, instead of copying data from the desc buf, here we let the mbuf reference the desc buf addr directly. Doing so, however, has one major issue: we can't update the used ring at the end of rte_vhost_dequeue_burst. Because we don't do the copy here, an update of the used ring would let the driver to reclaim the desc buf. As a result, DPDK might reference a stale memory region. To update the used ring properly, this patch does several tricks: - when mbuf references a desc buf, refcnt is added by 1. This is to pin lock the mbuf, so that a mbuf free from the DPDK won't actually free it, instead, refcnt is subtracted by 1. - We chain all those mbuf together (by tailq) And we check it every time on the rte_vhost_dequeue_burst entrance, to see if the mbuf is freed (when refcnt equals to 1). If that happens, it means we are the last user of this mbuf and we are safe to update the used ring. - "struct zcopy_mbuf" is introduced, to associate an mbuf with the right desc idx. Dequeue zero copy is introduced for performance reason, and some rough tests show about 50% perfomance boost for packet size 1500B. For small packets, (e.g. 64B), it actually slows a bit down (well, it could up to 15%). That is expected because this patch introduces some extra works, and it outweighs the benefit from saving few bytes copy. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com> Tested-by: Qian Xu <qian.q.xu@intel.com>
2016-10-09 07:27:57 +00:00
#include <sys/queue.h>
#include <unistd.h>
#include <linux/vhost.h>
#include <linux/virtio_net.h>
#include <sys/socket.h>
#include <linux/if.h>
#include <rte_log.h>
#include <rte_ether.h>
#include "rte_vhost.h"
/* Used to indicate that the device is running on a data core */
#define VIRTIO_DEV_RUNNING 1
/* Used to indicate that the device is ready to operate */
#define VIRTIO_DEV_READY 2
/* Backend value set by guest. */
#define VIRTIO_DEV_STOPPED -1
#define BUF_VECTOR_MAX 256
/**
* Structure contains buffer address, length and descriptor index
* from vring to do scatter RX.
*/
struct buf_vector {
uint64_t buf_addr;
uint32_t buf_len;
uint32_t desc_idx;
};
vhost: add dequeue zero copy The basic idea of dequeue zero copy is, instead of copying data from the desc buf, here we let the mbuf reference the desc buf addr directly. Doing so, however, has one major issue: we can't update the used ring at the end of rte_vhost_dequeue_burst. Because we don't do the copy here, an update of the used ring would let the driver to reclaim the desc buf. As a result, DPDK might reference a stale memory region. To update the used ring properly, this patch does several tricks: - when mbuf references a desc buf, refcnt is added by 1. This is to pin lock the mbuf, so that a mbuf free from the DPDK won't actually free it, instead, refcnt is subtracted by 1. - We chain all those mbuf together (by tailq) And we check it every time on the rte_vhost_dequeue_burst entrance, to see if the mbuf is freed (when refcnt equals to 1). If that happens, it means we are the last user of this mbuf and we are safe to update the used ring. - "struct zcopy_mbuf" is introduced, to associate an mbuf with the right desc idx. Dequeue zero copy is introduced for performance reason, and some rough tests show about 50% perfomance boost for packet size 1500B. For small packets, (e.g. 64B), it actually slows a bit down (well, it could up to 15%). That is expected because this patch introduces some extra works, and it outweighs the benefit from saving few bytes copy. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com> Tested-by: Qian Xu <qian.q.xu@intel.com>
2016-10-09 07:27:57 +00:00
/*
* A structure to hold some fields needed in zero copy code path,
* mainly for associating an mbuf with the right desc_idx.
*/
struct zcopy_mbuf {
struct rte_mbuf *mbuf;
uint32_t desc_idx;
uint16_t in_use;
TAILQ_ENTRY(zcopy_mbuf) next;
};
TAILQ_HEAD(zcopy_mbuf_list, zcopy_mbuf);
/**
* Structure contains variables relevant to RX/TX virtqueues.
*/
struct vhost_virtqueue {
struct vring_desc *desc;
struct vring_avail *avail;
struct vring_used *used;
uint32_t size;
uint16_t last_avail_idx;
uint16_t last_used_idx;
#define VIRTIO_INVALID_EVENTFD (-1)
#define VIRTIO_UNINITIALIZED_EVENTFD (-2)
/* Backend value to determine if device should started/stopped */
int backend;
/* Used to notify the guest (trigger interrupt) */
int callfd;
/* Currently unused as polling mode is enabled */
int kickfd;
int enabled;
/* Physical address of used ring, for logging */
uint64_t log_guest_addr;
vhost: add dequeue zero copy The basic idea of dequeue zero copy is, instead of copying data from the desc buf, here we let the mbuf reference the desc buf addr directly. Doing so, however, has one major issue: we can't update the used ring at the end of rte_vhost_dequeue_burst. Because we don't do the copy here, an update of the used ring would let the driver to reclaim the desc buf. As a result, DPDK might reference a stale memory region. To update the used ring properly, this patch does several tricks: - when mbuf references a desc buf, refcnt is added by 1. This is to pin lock the mbuf, so that a mbuf free from the DPDK won't actually free it, instead, refcnt is subtracted by 1. - We chain all those mbuf together (by tailq) And we check it every time on the rte_vhost_dequeue_burst entrance, to see if the mbuf is freed (when refcnt equals to 1). If that happens, it means we are the last user of this mbuf and we are safe to update the used ring. - "struct zcopy_mbuf" is introduced, to associate an mbuf with the right desc idx. Dequeue zero copy is introduced for performance reason, and some rough tests show about 50% perfomance boost for packet size 1500B. For small packets, (e.g. 64B), it actually slows a bit down (well, it could up to 15%). That is expected because this patch introduces some extra works, and it outweighs the benefit from saving few bytes copy. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com> Tested-by: Qian Xu <qian.q.xu@intel.com>
2016-10-09 07:27:57 +00:00
uint16_t nr_zmbuf;
uint16_t zmbuf_size;
uint16_t last_zmbuf_idx;
struct zcopy_mbuf *zmbufs;
struct zcopy_mbuf_list zmbuf_list;
struct vring_used_elem *shadow_used_ring;
uint16_t shadow_used_idx;
} __rte_cache_aligned;
/* Old kernels have no such macros defined */
#ifndef VIRTIO_NET_F_GUEST_ANNOUNCE
#define VIRTIO_NET_F_GUEST_ANNOUNCE 21
#endif
#ifndef VIRTIO_NET_F_MQ
#define VIRTIO_NET_F_MQ 22
#endif
#define VHOST_MAX_VRING 0x100
#define VHOST_MAX_QUEUE_PAIRS 0x80
#ifndef VIRTIO_NET_F_MTU
#define VIRTIO_NET_F_MTU 3
#endif
/*
* Define virtio 1.0 for older kernels
*/
#ifndef VIRTIO_F_VERSION_1
#define VIRTIO_F_VERSION_1 32
#endif
#define VHOST_USER_F_PROTOCOL_FEATURES 30
/* Features supported by this builtin vhost-user net driver. */
#define VIRTIO_NET_SUPPORTED_FEATURES ((1ULL << VIRTIO_NET_F_MRG_RXBUF) | \
(1ULL << VIRTIO_NET_F_CTRL_VQ) | \
(1ULL << VIRTIO_NET_F_CTRL_RX) | \
(1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE) | \
(1ULL << VIRTIO_NET_F_MQ) | \
(1ULL << VIRTIO_F_VERSION_1) | \
(1ULL << VHOST_F_LOG_ALL) | \
(1ULL << VHOST_USER_F_PROTOCOL_FEATURES) | \
(1ULL << VIRTIO_NET_F_HOST_TSO4) | \
(1ULL << VIRTIO_NET_F_HOST_TSO6) | \
(1ULL << VIRTIO_NET_F_CSUM) | \
(1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
(1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
(1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
(1ULL << VIRTIO_RING_F_INDIRECT_DESC) | \
(1ULL << VIRTIO_NET_F_MTU))
struct guest_page {
uint64_t guest_phys_addr;
uint64_t host_phys_addr;
uint64_t size;
};
/**
* Device structure contains all configuration information relating
* to the device.
*/
struct virtio_net {
/* Frontend (QEMU) memory and memory region information */
struct rte_vhost_memory *mem;
uint64_t features;
uint64_t protocol_features;
int vid;
uint32_t flags;
uint16_t vhost_hlen;
/* to tell if we need broadcast rarp packet */
rte_atomic16_t broadcast_rarp;
uint32_t nr_vring;
vhost: add dequeue zero copy The basic idea of dequeue zero copy is, instead of copying data from the desc buf, here we let the mbuf reference the desc buf addr directly. Doing so, however, has one major issue: we can't update the used ring at the end of rte_vhost_dequeue_burst. Because we don't do the copy here, an update of the used ring would let the driver to reclaim the desc buf. As a result, DPDK might reference a stale memory region. To update the used ring properly, this patch does several tricks: - when mbuf references a desc buf, refcnt is added by 1. This is to pin lock the mbuf, so that a mbuf free from the DPDK won't actually free it, instead, refcnt is subtracted by 1. - We chain all those mbuf together (by tailq) And we check it every time on the rte_vhost_dequeue_burst entrance, to see if the mbuf is freed (when refcnt equals to 1). If that happens, it means we are the last user of this mbuf and we are safe to update the used ring. - "struct zcopy_mbuf" is introduced, to associate an mbuf with the right desc idx. Dequeue zero copy is introduced for performance reason, and some rough tests show about 50% perfomance boost for packet size 1500B. For small packets, (e.g. 64B), it actually slows a bit down (well, it could up to 15%). That is expected because this patch introduces some extra works, and it outweighs the benefit from saving few bytes copy. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com> Tested-by: Qian Xu <qian.q.xu@intel.com>
2016-10-09 07:27:57 +00:00
int dequeue_zero_copy;
struct vhost_virtqueue *virtqueue[VHOST_MAX_QUEUE_PAIRS * 2];
#define IF_NAME_SZ (PATH_MAX > IFNAMSIZ ? PATH_MAX : IFNAMSIZ)
char ifname[IF_NAME_SZ];
uint64_t log_size;
uint64_t log_base;
uint64_t log_addr;
struct ether_addr mac;
uint16_t mtu;
struct vhost_device_ops const *notify_ops;
uint32_t nr_guest_pages;
uint32_t max_guest_pages;
struct guest_page *guest_pages;
} __rte_cache_aligned;
#define VHOST_LOG_PAGE 4096
static __rte_always_inline void
vhost_log_page(uint8_t *log_base, uint64_t page)
{
log_base[page / 8] |= 1 << (page % 8);
}
static __rte_always_inline void
vhost_log_write(struct virtio_net *dev, uint64_t addr, uint64_t len)
{
uint64_t page;
if (likely(((dev->features & (1ULL << VHOST_F_LOG_ALL)) == 0) ||
!dev->log_base || !len))
return;
if (unlikely(dev->log_size <= ((addr + len - 1) / VHOST_LOG_PAGE / 8)))
return;
/* To make sure guest memory updates are committed before logging */
rte_smp_wmb();
page = addr / VHOST_LOG_PAGE;
while (page * VHOST_LOG_PAGE < addr + len) {
vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page);
page += 1;
}
}
static __rte_always_inline void
vhost_log_used_vring(struct virtio_net *dev, struct vhost_virtqueue *vq,
uint64_t offset, uint64_t len)
{
vhost_log_write(dev, vq->log_guest_addr + offset, len);
}
/* Macros for printing using RTE_LOG */
#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
#define RTE_LOGTYPE_VHOST_DATA RTE_LOGTYPE_USER1
#ifdef RTE_LIBRTE_VHOST_DEBUG
#define VHOST_MAX_PRINT_BUFF 6072
#define LOG_LEVEL RTE_LOG_DEBUG
#define LOG_DEBUG(log_type, fmt, args...) RTE_LOG(DEBUG, log_type, fmt, ##args)
#define PRINT_PACKET(device, addr, size, header) do { \
char *pkt_addr = (char *)(addr); \
unsigned int index; \
char packet[VHOST_MAX_PRINT_BUFF]; \
\
if ((header)) \
snprintf(packet, VHOST_MAX_PRINT_BUFF, "(%d) Header size %d: ", (device->vid), (size)); \
else \
snprintf(packet, VHOST_MAX_PRINT_BUFF, "(%d) Packet size %d: ", (device->vid), (size)); \
for (index = 0; index < (size); index++) { \
snprintf(packet + strnlen(packet, VHOST_MAX_PRINT_BUFF), VHOST_MAX_PRINT_BUFF - strnlen(packet, VHOST_MAX_PRINT_BUFF), \
"%02hhx ", pkt_addr[index]); \
} \
snprintf(packet + strnlen(packet, VHOST_MAX_PRINT_BUFF), VHOST_MAX_PRINT_BUFF - strnlen(packet, VHOST_MAX_PRINT_BUFF), "\n"); \
\
LOG_DEBUG(VHOST_DATA, "%s", packet); \
} while (0)
#else
#define LOG_LEVEL RTE_LOG_INFO
#define LOG_DEBUG(log_type, fmt, args...) do {} while (0)
#define PRINT_PACKET(device, addr, size, header) do {} while (0)
#endif
extern uint64_t VHOST_FEATURES;
#define MAX_VHOST_DEVICE 1024
extern struct virtio_net *vhost_devices[MAX_VHOST_DEVICE];
/* Convert guest physical address to host physical address */
static __rte_always_inline phys_addr_t
gpa_to_hpa(struct virtio_net *dev, uint64_t gpa, uint64_t size)
{
uint32_t i;
struct guest_page *page;
for (i = 0; i < dev->nr_guest_pages; i++) {
page = &dev->guest_pages[i];
if (gpa >= page->guest_phys_addr &&
gpa + size < page->guest_phys_addr + page->size) {
return gpa - page->guest_phys_addr +
page->host_phys_addr;
}
}
return 0;
}
struct virtio_net *get_device(int vid);
int vhost_new_device(void);
void cleanup_device(struct virtio_net *dev, int destroy);
void reset_device(struct virtio_net *dev);
void vhost_destroy_device(int);
int alloc_vring_queue(struct virtio_net *dev, uint32_t vring_idx);
void vhost_set_ifname(int, const char *if_name, unsigned int if_len);
void vhost_enable_dequeue_zero_copy(int vid);
struct vhost_device_ops const *vhost_driver_callback_get(const char *path);
/*
* Backend-specific cleanup.
*
* TODO: fix it; we have one backend now
*/
void vhost_backend_cleanup(struct virtio_net *dev);
#endif /* _VHOST_NET_CDEV_H_ */