diff mbox

[RFC,03/10] Chain lookup and packets caching.

Message ID 1453760690-21221-4-git-send-email-wexu@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Wei Xu Jan. 25, 2016, 10:24 p.m. UTC
Looking up chain by protocol and invoke coalescing
callback, cache the packet if can't handle it.

Signed-off-by: Wei Xu <wexu@redhat.com>
---
 hw/net/virtio-net.c | 171 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 170 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 4e9458e..7a6cd4c 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -14,10 +14,12 @@ 
 #include "qemu/iov.h"
 #include "hw/virtio/virtio.h"
 #include "net/net.h"
+#include "net/eth.h"
 #include "net/checksum.h"
 #include "net/tap.h"
 #include "qemu/error-report.h"
 #include "qemu/timer.h"
+#include "qemu/sockets.h"
 #include "hw/virtio/virtio-net.h"
 #include "net/vhost_net.h"
 #include "hw/virtio/virtio-bus.h"
@@ -37,6 +39,21 @@ 
 #define endof(container, field) \
     (offsetof(container, field) + sizeof(((container *)0)->field))
 
+#define VIRTIO_HEADER   12    /* Virtio net header size */
+#define IP_OFFSET (VIRTIO_HEADER + sizeof(struct eth_header))
+
+#define MAX_VIRTIO_IP_PAYLOAD  (65535 + IP_OFFSET)
+
+/* Global statistics */
+static uint32_t rsc_chain_no_mem;
+
+/* Switcher to enable/disable rsc */
+static bool virtio_net_rsc_bypass;
+
+/* Coalesce callback for ipv4/6 */
+typedef int32_t (VirtioNetCoalesce) (NetRscChain *chain, NetRscSeg *seg,
+                                     const uint8_t *buf, size_t size);
+
 typedef struct VirtIOFeature {
     uint32_t flags;
     size_t end;
@@ -1019,7 +1036,8 @@  static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
     return 0;
 }
 
-static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t size)
+static ssize_t virtio_net_do_receive(NetClientState *nc,
+                                  const uint8_t *buf, size_t size)
 {
     VirtIONet *n = qemu_get_nic_opaque(nc);
     VirtIONetQueue *q = virtio_net_get_subqueue(nc);
@@ -1623,6 +1641,157 @@  static void virtio_net_rsc_cleanup(VirtIONet *n)
     }
 }
 
+static int virtio_net_rsc_cache_buf(NetRscChain *chain, NetClientState *nc,
+                                    const uint8_t *buf, size_t size)
+{
+    NetRscSeg *seg;
+
+    seg = g_malloc(sizeof(NetRscSeg));
+    if (!seg) {
+        return 0;
+    }
+
+    seg->buf = g_malloc(MAX_VIRTIO_IP_PAYLOAD);
+    if (!seg->buf) {
+        goto out;
+    }
+
+    memmove(seg->buf, buf, size);
+    seg->size = size;
+    seg->dup_ack_count = 0;
+    seg->is_coalesced = 0;
+    seg->nc = nc;
+
+    QTAILQ_INSERT_TAIL(&chain->buffers, seg, next);
+    return size;
+
+out:
+    g_free(seg);
+    return 0;
+}
+
+
+static int32_t virtio_net_rsc_try_coalesce4(NetRscChain *chain,
+                       NetRscSeg *seg, const uint8_t *buf, size_t size)
+{
+    return RSC_FINAL;
+}
+
+static size_t virtio_net_rsc_callback(NetRscChain *chain, NetClientState *nc,
+                const uint8_t *buf, size_t size, VirtioNetCoalesce *coalesce)
+{
+    int ret;
+    NetRscSeg *seg, *nseg;
+
+    if (QTAILQ_EMPTY(&chain->buffers)) {
+        if (!virtio_net_rsc_cache_buf(chain, nc, buf, size)) {
+            return 0;
+        } else {
+            return size;
+        }
+    }
+
+    QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, nseg) {
+        ret = coalesce(chain, seg, buf, size);
+        if (RSC_FINAL == ret) {
+            ret = virtio_net_do_receive(seg->nc, seg->buf, seg->size);
+            QTAILQ_REMOVE(&chain->buffers, seg, next);
+            g_free(seg->buf);
+            g_free(seg);
+            if (ret == 0) {
+                /* Send failed */
+                return 0;
+            }
+
+            /* Send current packet */
+            return virtio_net_do_receive(nc, buf, size);
+        } else if (RSC_NO_MATCH == ret) {
+            continue;
+        } else {
+            /* Coalesced, mark coalesced flag to tell calc cksum for ipv4 */
+            seg->is_coalesced = 1;
+            return size;
+        }
+    }
+
+    return virtio_net_rsc_cache_buf(chain, nc, buf, size);
+}
+
+static size_t virtio_net_rsc_receive4(void *opq, NetClientState* nc,
+                                      const uint8_t *buf, size_t size)
+{
+    NetRscChain *chain;
+
+    chain = (NetRscChain *)opq;
+    return virtio_net_rsc_callback(chain, nc, buf, size,
+                                   virtio_net_rsc_try_coalesce4);
+}
+
+static NetRscChain *virtio_net_rsc_lookup_chain(NetClientState *nc,
+                                                uint16_t proto)
+{
+    VirtIONet *n;
+    NetRscChain *chain;
+    NICState *nic;
+
+    /* Only handle IPv4/6 */
+    if (proto != (uint16_t)ETH_P_IP) {
+        return NULL;
+    }
+
+    nic = (NICState *)nc;
+    n = container_of(&nic, VirtIONet, nic);
+    QTAILQ_FOREACH(chain, &n->rsc_chains, next) {
+        if (chain->proto == proto) {
+            return chain;
+        }
+    }
+
+    chain = g_malloc(sizeof(*chain));
+    if (!chain) {
+        rsc_chain_no_mem++;
+        return NULL;
+    }
+
+    chain->proto = proto;
+    chain->do_receive = virtio_net_rsc_receive4;
+
+    QTAILQ_INIT(&chain->buffers);
+    QTAILQ_INSERT_TAIL(&n->rsc_chains, chain, next);
+    return chain;
+}
+
+static ssize_t virtio_net_rsc_receive(NetClientState *nc,
+                                      const uint8_t *buf, size_t size)
+{
+    uint16_t proto;
+    NetRscChain *chain;
+    struct eth_header *eth;
+
+    if (size < IP_OFFSET) {
+        return virtio_net_do_receive(nc, buf, size);
+    }
+
+    eth = (struct eth_header *)(buf + VIRTIO_HEADER);
+    proto = htons(eth->h_proto);
+    chain = virtio_net_rsc_lookup_chain(nc, proto);
+    if (!chain) {
+        return virtio_net_do_receive(nc, buf, size);
+    } else {
+        return chain->do_receive(chain, nc, buf, size);
+    }
+}
+
+static ssize_t virtio_net_receive(NetClientState *nc,
+                                  const uint8_t *buf, size_t size)
+{
+    if (virtio_net_rsc_bypass) {
+        return virtio_net_do_receive(nc, buf, size);
+    } else {
+        return virtio_net_rsc_receive(nc, buf, size);
+    }
+}
+
 static NetClientInfo net_virtio_info = {
     .type = NET_CLIENT_OPTIONS_KIND_NIC,
     .size = sizeof(NICState),