free_percpu(po->tx_ring.pending_refcnt);
}
-static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
+#define ROOM_POW_OFF 2
+#define ROOM_NONE 0x0
+#define ROOM_LOW 0x1
+#define ROOM_NORMAL 0x2
+
+static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
+{
+ int idx, len;
+
+ len = po->rx_ring.frame_max + 1;
+ idx = po->rx_ring.head;
+ if (pow_off)
+ idx += len >> pow_off;
+ if (idx >= len)
+ idx -= len;
+ return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
+}
+
+static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
+{
+ int idx, len;
+
+ len = po->rx_ring.prb_bdqc.knum_blocks;
+ idx = po->rx_ring.prb_bdqc.kactive_blk_num;
+ if (pow_off)
+ idx += len >> pow_off;
+ if (idx >= len)
+ idx -= len;
+ return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
+}
+
+static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
{
struct sock *sk = &po->sk;
+ int ret = ROOM_NONE;
+
+ if (po->prot_hook.func != tpacket_rcv) {
+ int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
+ - (skb ? skb->truesize : 0);
+ if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
+ return ROOM_NORMAL;
+ else if (avail > 0)
+ return ROOM_LOW;
+ else
+ return ROOM_NONE;
+ }
+
+ if (po->tp_version == TPACKET_V3) {
+ if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
+ ret = ROOM_NORMAL;
+ else if (__tpacket_v3_has_room(po, 0))
+ ret = ROOM_LOW;
+ } else {
+ if (__tpacket_has_room(po, ROOM_POW_OFF))
+ ret = ROOM_NORMAL;
+ else if (__tpacket_has_room(po, 0))
+ ret = ROOM_LOW;
+ }
+
+ return ret;
+}
+
+static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
+{
+ int ret;
bool has_room;
- if (po->prot_hook.func != tpacket_rcv)
- return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
- <= sk->sk_rcvbuf;
+ if (po->prot_hook.func == tpacket_rcv) {
+ spin_lock(&po->sk.sk_receive_queue.lock);
+ ret = __packet_rcv_has_room(po, skb);
+ spin_unlock(&po->sk.sk_receive_queue.lock);
+ } else {
+ ret = __packet_rcv_has_room(po, skb);
+ }
- spin_lock(&sk->sk_receive_queue.lock);
- if (po->tp_version == TPACKET_V3)
- has_room = prb_lookup_block(po, &po->rx_ring,
- po->rx_ring.prb_bdqc.kactive_blk_num,
- TP_STATUS_KERNEL);
- else
- has_room = packet_lookup_frame(po, &po->rx_ring,
- po->rx_ring.head,
- TP_STATUS_KERNEL);
- spin_unlock(&sk->sk_receive_queue.lock);
+ has_room = ret == ROOM_NORMAL;
+ if (po->pressure == has_room)
+ xchg(&po->pressure, !has_room);
- return has_room;
+ return ret;
}
static void packet_sock_destruct(struct sock *sk)
return x;
}
+static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
+{
+ u32 rxhash;
+ int i, count = 0;
+
+ rxhash = skb_get_hash(skb);
+ for (i = 0; i < ROLLOVER_HLEN; i++)
+ if (po->rollover->history[i] == rxhash)
+ count++;
+
+ po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
+ return count > (ROLLOVER_HLEN >> 1);
+}
+
static unsigned int fanout_demux_hash(struct packet_fanout *f,
struct sk_buff *skb,
unsigned int num)
static unsigned int fanout_demux_rollover(struct packet_fanout *f,
struct sk_buff *skb,
- unsigned int idx, unsigned int skip,
+ unsigned int idx, bool try_self,
unsigned int num)
{
- unsigned int i, j;
+ struct packet_sock *po, *po_next;
+ unsigned int i, j, room;
- i = j = min_t(int, f->next[idx], num - 1);
+ po = pkt_sk(f->arr[idx]);
+
+ if (try_self) {
+ room = packet_rcv_has_room(po, skb);
+ if (room == ROOM_NORMAL ||
+ (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
+ return idx;
+ }
+
+ i = j = min_t(int, po->rollover->sock, num - 1);
do {
- if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
+ po_next = pkt_sk(f->arr[i]);
+ if (po_next != po && !po_next->pressure &&
+ packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
if (i != j)
- f->next[idx] = i;
+ po->rollover->sock = i;
return i;
}
+
if (++i == num)
i = 0;
} while (i != j);
idx = fanout_demux_qm(f, skb, num);
break;
case PACKET_FANOUT_ROLLOVER:
- idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
+ idx = fanout_demux_rollover(f, skb, 0, false, num);
break;
}
- po = pkt_sk(f->arr[idx]);
- if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
- unlikely(!packet_rcv_has_room(po, skb))) {
- idx = fanout_demux_rollover(f, skb, idx, idx, num);
- po = pkt_sk(f->arr[idx]);
- }
+ if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
+ idx = fanout_demux_rollover(f, skb, idx, true, num);
+ po = pkt_sk(f->arr[idx]);
return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
}
if (po->fanout)
return -EALREADY;
+ if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER) {
+ po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL);
+ if (!po->rollover)
+ return -ENOMEM;
+ }
+
mutex_lock(&fanout_mutex);
match = NULL;
list_for_each_entry(f, &fanout_list, list) {
}
out:
mutex_unlock(&fanout_mutex);
+ if (err) {
+ kfree(po->rollover);
+ po->rollover = NULL;
+ }
return err;
}
kfree(f);
}
mutex_unlock(&fanout_mutex);
+
+ kfree(po->rollover);
}
static const struct proto_ops packet_ops;
tlen = dev->needed_tailroom;
skb = sock_alloc_send_skb(&po->sk,
hlen + tlen + sizeof(struct sockaddr_ll),
- 0, &err);
+ !need_wait, &err);
- if (unlikely(skb == NULL))
+ if (unlikely(skb == NULL)) {
+ /* we assume the socket was initially writeable ... */
+ if (likely(len_sum > 0))
+ err = len_sum;
goto out_status;
-
+ }
tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
addr, hlen);
if (tp_len > dev->mtu + dev->hard_header_len) {
sock->state = SS_UNCONNECTED;
err = -ENOBUFS;
- sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
+ sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
if (sk == NULL)
goto out;
spin_lock_init(&po->bind_lock);
mutex_init(&po->pg_vec_lock);
+ po->rollover = NULL;
po->prot_hook.func = packet_rcv;
if (sock->type == SOCK_PACKET)
if (skb == NULL)
goto out;
+ if (pkt_sk(sk)->pressure)
+ packet_rcv_has_room(pkt_sk(sk), NULL);
+
if (pkt_sk(sk)->has_vnet_hdr) {
struct virtio_net_hdr vnet_hdr = { 0 };
TP_STATUS_KERNEL))
mask |= POLLIN | POLLRDNORM;
}
+ if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
+ xchg(&po->pressure, 0);
spin_unlock_bh(&sk->sk_receive_queue.lock);
spin_lock_bh(&sk->sk_write_queue.lock);
if (po->tx_ring.pg_vec) {
projects / cascardo / linux.git / blobdiff