Support mergable rx buffers for virtio-net. This helps reduce the amount
of memory the guest kernel has to allocate per rx vq.
Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
---
tools/kvm/include/kvm/uip.h | 4 ++--
tools/kvm/include/kvm/util.h | 3 +++
tools/kvm/net/uip/core.c | 54 +++++---------------------------------------
tools/kvm/net/uip/tcp.c | 2 +-
tools/kvm/net/uip/udp.c | 2 +-
tools/kvm/util/util.c | 15 ++++++++++++
tools/kvm/virtio/net.c | 37 ++++++++++++++++++++++--------
7 files changed, 55 insertions(+), 62 deletions(-)
diff --git a/tools/kvm/include/kvm/uip.h b/tools/kvm/include/kvm/uip.h
index ac248d2..fa82f10 100644
--- a/tools/kvm/include/kvm/uip.h
+++ b/tools/kvm/include/kvm/uip.h
@@ -252,7 +252,7 @@ struct uip_tcp_socket {
};
struct uip_tx_arg {
- struct virtio_net_hdr *vnet;
+ struct virtio_net_hdr_mrg_rxbuf *vnet;
struct uip_info *info;
struct uip_eth *eth;
int vnet_len;
@@ -332,7 +332,7 @@ static inline u16 uip_eth_hdrlen(struct uip_eth *eth)
}
int uip_tx(struct iovec *iov, u16 out, struct uip_info *info);
-int uip_rx(struct iovec *iov, u16 in, struct uip_info *info);
+int uip_rx(unsigned char *buffer, u32 length, struct uip_info *info);
int uip_init(struct uip_info *info);
int uip_tx_do_ipv4_udp_dhcp(struct uip_tx_arg *arg);
diff --git a/tools/kvm/include/kvm/util.h b/tools/kvm/include/kvm/util.h
index 0df9f0d..6f8ac83 100644
--- a/tools/kvm/include/kvm/util.h
+++ b/tools/kvm/include/kvm/util.h
@@ -22,6 +22,7 @@
#include <sys/param.h>
#include <sys/types.h>
#include <linux/types.h>
+#include <sys/uio.h>
#ifdef __GNUC__
#define NORETURN __attribute__((__noreturn__))
@@ -94,4 +95,6 @@ struct kvm;
void *mmap_hugetlbfs(struct kvm *kvm, const char *htlbfs_path, u64 size);
void *mmap_anon_or_hugetlbfs(struct kvm *kvm, const char *hugetlbfs_path, u64 size);
+int memcpy_toiovecend(const struct iovec *iov, int iovlen, unsigned char *kdata, size_t len);
+
#endif /* KVM__UTIL_H */
diff --git a/tools/kvm/net/uip/core.c b/tools/kvm/net/uip/core.c
index 4e5bb82..d9e9993 100644
--- a/tools/kvm/net/uip/core.c
+++ b/tools/kvm/net/uip/core.c
@@ -7,7 +7,7 @@
int uip_tx(struct iovec *iov, u16 out, struct uip_info *info)
{
- struct virtio_net_hdr *vnet;
+ struct virtio_net_hdr_mrg_rxbuf *vnet;
struct uip_tx_arg arg;
int eth_len, vnet_len;
struct uip_eth *eth;
@@ -74,63 +74,21 @@ int uip_tx(struct iovec *iov, u16 out, struct uip_info *info)
return vnet_len + eth_len;
}
-int uip_rx(struct iovec *iov, u16 in, struct uip_info *info)
+int uip_rx(unsigned char *buffer, u32 length, struct uip_info *info)
{
- struct virtio_net_hdr *vnet;
- struct uip_eth *eth;
struct uip_buf *buf;
- int vnet_len;
- int eth_len;
- char *p;
int len;
- int cnt;
- int i;
/*
* Sleep until there is a buffer for guest
*/
buf = uip_buf_get_used(info);
- /*
- * Fill device to guest buffer, vnet hdr fisrt
- */
- vnet_len = iov[0].iov_len;
- vnet = iov[0].iov_base;
- if (buf->vnet_len > vnet_len) {
- len = -1;
- goto out;
- }
- memcpy(vnet, buf->vnet, buf->vnet_len);
-
- /*
- * Then, the real eth data
- * Note: Be sure buf->eth_len is not bigger than the buffer len that guest provides
- */
- cnt = buf->eth_len;
- p = buf->eth;
- for (i = 1; i < in; i++) {
- eth_len = iov[i].iov_len;
- eth = iov[i].iov_base;
- if (cnt > eth_len) {
- memcpy(eth, p, eth_len);
- cnt -= eth_len;
- p += eth_len;
- } else {
- memcpy(eth, p, cnt);
- cnt -= cnt;
- break;
- }
- }
-
- if (cnt) {
- pr_warning("uip_rx error");
- len = -1;
- goto out;
- }
+ memcpy(buffer, buf->vnet, buf->vnet_len);
+ memcpy(buffer + buf->vnet_len, buf->eth, buf->eth_len);
len = buf->vnet_len + buf->eth_len;
-out:
uip_buf_set_free(info, buf);
return len;
}
@@ -172,8 +130,8 @@ int uip_init(struct uip_info *info)
}
list_for_each_entry(buf, buf_head, list) {
- buf->vnet = malloc(sizeof(struct virtio_net_hdr));
- buf->vnet_len = sizeof(struct virtio_net_hdr);
+ buf->vnet = malloc(sizeof(struct virtio_net_hdr_mrg_rxbuf));
+ buf->vnet_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
buf->eth = malloc(1024*64 + sizeof(struct uip_pseudo_hdr));
buf->eth_len = 1024*64 + sizeof(struct uip_pseudo_hdr);
diff --git a/tools/kvm/net/uip/tcp.c b/tools/kvm/net/uip/tcp.c
index 9044f40..a99b95e 100644
--- a/tools/kvm/net/uip/tcp.c
+++ b/tools/kvm/net/uip/tcp.c
@@ -153,7 +153,7 @@ static int uip_tcp_payload_send(struct uip_tcp_socket *sk, u8 flag, u16 payload_
/*
* virtio_net_hdr
*/
- buf->vnet_len = sizeof(struct virtio_net_hdr);
+ buf->vnet_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
memset(buf->vnet, 0, buf->vnet_len);
buf->eth_len = ntohs(ip2->len) + uip_eth_hdrlen(&ip2->eth);
diff --git a/tools/kvm/net/uip/udp.c b/tools/kvm/net/uip/udp.c
index 31c417c..083c221 100644
--- a/tools/kvm/net/uip/udp.c
+++ b/tools/kvm/net/uip/udp.c
@@ -142,7 +142,7 @@ int uip_udp_make_pkg(struct uip_info *info, struct uip_udp_socket *sk, struct ui
/*
* virtio_net_hdr
*/
- buf->vnet_len = sizeof(struct virtio_net_hdr);
+ buf->vnet_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
memset(buf->vnet, 0, buf->vnet_len);
buf->eth_len = ntohs(ip2->len) + uip_eth_hdrlen(&ip2->eth);
diff --git a/tools/kvm/util/util.c b/tools/kvm/util/util.c
index c11a15a..4e0069c 100644
--- a/tools/kvm/util/util.c
+++ b/tools/kvm/util/util.c
@@ -9,6 +9,7 @@
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/statfs.h>
+#include <linux/kernel.h>
static void report(const char *prefix, const char *err, va_list params)
{
@@ -131,3 +132,17 @@ void *mmap_anon_or_hugetlbfs(struct kvm *kvm, const char *hugetlbfs_path, u64 si
return mmap(NULL, size, PROT_RW, MAP_ANON_NORESERVE, -1, 0);
}
}
+
+int memcpy_toiovecend(const struct iovec *iov, int iovlen, unsigned char *kdata, size_t len)
+{
+ size_t copy, start_len = len;
+
+ for (; len > 0 && iovlen > 0; ++iov, --iovlen) {
+ copy = min(iov->iov_len, len);
+ memcpy(iov->iov_base, kdata, copy);
+ kdata += copy;
+ len -= copy;
+ }
+
+ return start_len - len;
+}
diff --git a/tools/kvm/virtio/net.c b/tools/kvm/virtio/net.c
index c0a8f12..c99c5a6 100644
--- a/tools/kvm/virtio/net.c
+++ b/tools/kvm/virtio/net.c
@@ -32,8 +32,8 @@
struct net_dev;
struct net_dev_operations {
- int (*rx)(struct iovec *iov, u16 in, struct net_dev *ndev);
- int (*tx)(struct iovec *iov, u16 in, struct net_dev *ndev);
+ int (*rx)(unsigned char *buffer, u32 length, struct net_dev *ndev);
+ int (*tx)(struct iovec *iov, u16 out, struct net_dev *ndev);
};
struct net_dev {
@@ -63,6 +63,8 @@ struct net_dev {
static LIST_HEAD(ndevs);
static int compat_id = -1;
+#define MAX_PACKET_SIZE ((u16)(-1))
+
static void *virtio_net_rx_thread(void *p)
{
struct iovec iov[VIRTIO_NET_QUEUE_SIZE];
@@ -90,9 +92,23 @@ static void *virtio_net_rx_thread(void *p)
mutex_unlock(&ndev->io_lock[id]);
while (virt_queue__available(vq)) {
+ unsigned char buffer[MAX_PACKET_SIZE];
+ struct virtio_net_hdr_mrg_rxbuf *hdr;
+
+ len = ndev->ops->rx(buffer, MAX_PACKET_SIZE, ndev);
head = virt_queue__get_iov(vq, iov, &out, &in, kvm);
- len = ndev->ops->rx(iov, in, ndev);
- virt_queue__set_used_elem(vq, head, len);
+ hdr = (void *)iov[0].iov_base;
+ while (len) {
+ int copied;
+
+ copied = memcpy_toiovecend(iov, in, buffer, len);
+ len -= copied;
+ hdr->num_buffers++;
+ virt_queue__set_used_elem(vq, head, copied);
+ if (len == 0)
+ break;
+ head = virt_queue__get_iov(vq, iov, &out, &in, kvm);
+ }
/* We should interrupt guest right now, otherwise latency is huge. */
if (virtio_queue__should_signal(vq))
@@ -241,7 +257,7 @@ static bool virtio_net__tap_init(const struct virtio_net_params *params,
goto fail;
}
- hdr_len = sizeof(struct virtio_net_hdr);
+ hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
if (ioctl(ndev->tap_fd, TUNSETVNETHDRSZ, &hdr_len) < 0)
pr_warning("Config tap device TUNSETVNETHDRSZ error");
@@ -300,9 +316,9 @@ static inline int tap_ops_tx(struct iovec *iov, u16 out, struct net_dev *ndev)
return writev(ndev->tap_fd, iov, out);
}
-static inline int tap_ops_rx(struct iovec *iov, u16 in, struct net_dev *ndev)
+static inline int tap_ops_rx(unsigned char *buffer, u32 length, struct net_dev *ndev)
{
- return readv(ndev->tap_fd, iov, in);
+ return read(ndev->tap_fd, buffer, length);
}
static inline int uip_ops_tx(struct iovec *iov, u16 out, struct net_dev *ndev)
@@ -310,9 +326,9 @@ static inline int uip_ops_tx(struct iovec *iov, u16 out, struct net_dev *ndev)
return uip_tx(iov, out, &ndev->info);
}
-static inline int uip_ops_rx(struct iovec *iov, u16 in, struct net_dev *ndev)
+static inline int uip_ops_rx(unsigned char *buffer, u32 length, struct net_dev *ndev)
{
- return uip_rx(iov, in, &ndev->info);
+ return uip_rx(buffer, length, &ndev->info);
}
static struct net_dev_operations tap_ops = {
@@ -347,7 +363,8 @@ static u32 get_host_features(struct kvm *kvm, void *dev)
| 1UL << VIRTIO_RING_F_EVENT_IDX
| 1UL << VIRTIO_RING_F_INDIRECT_DESC
| 1UL << VIRTIO_NET_F_CTRL_VQ
- | 1UL << (ndev->queue_pairs > 1 ? VIRTIO_NET_F_MQ : 0);
+ | 1UL << (ndev->queue_pairs > 1 ? VIRTIO_NET_F_MQ : 0)
+ | 1UL << VIRTIO_NET_F_MRG_RXBUF;
}
static void set_guest_features(struct kvm *kvm, void *dev, u32 features)
--
1.8.2.1
--
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