aboutsummaryrefslogtreecommitdiffstats
path: root/net/iucv
diff options
context:
space:
mode:
authorUrsula Braun <braunu@de.ibm.com>2007-10-08 02:03:31 -0700
committerDavid S. Miller <davem@sunset.davemloft.net>2007-10-10 16:54:51 -0700
commitf0703c80e5156406ad947cb67fe277725b48080f (patch)
tree428f16c8e188763cfa2cadc26708bf785a8958b8 /net/iucv
parent57f20448032158ad00b1e74f479515c689998be9 (diff)
[AF_IUCV]: postpone receival of iucv-packets
AF_IUCV socket programs may waste Linux storage, because af_iucv allocates an skb whenever posted by the receive callback routine and receives the message immediately. Message receival is now postponed if data from previous callbacks has not yet been transferred to the receiving socket program. Instead a message handle is saved in a message queue as a reminder. Once messages could be given to the receiving socket program, there is an additional checking for entries in the message queue, followed by skb allocation and message receival if applicable. Signed-off-by: Ursula Braun <braunu@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/iucv')
-rw-r--r--net/iucv/af_iucv.c211
1 files changed, 125 insertions, 86 deletions
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index 65358722c397..43e01c8d382b 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -224,6 +224,8 @@ static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
spin_lock_init(&iucv_sk(sk)->accept_q_lock);
skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
+ INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
+ spin_lock_init(&iucv_sk(sk)->message_q.lock);
skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
iucv_sk(sk)->send_tag = 0;
@@ -673,6 +675,90 @@ out:
return err;
}
+static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
+{
+ int dataleft, size, copied = 0;
+ struct sk_buff *nskb;
+
+ dataleft = len;
+ while (dataleft) {
+ if (dataleft >= sk->sk_rcvbuf / 4)
+ size = sk->sk_rcvbuf / 4;
+ else
+ size = dataleft;
+
+ nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
+ if (!nskb)
+ return -ENOMEM;
+
+ memcpy(nskb->data, skb->data + copied, size);
+ copied += size;
+ dataleft -= size;
+
+ skb_reset_transport_header(nskb);
+ skb_reset_network_header(nskb);
+ nskb->len = size;
+
+ skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
+ }
+
+ return 0;
+}
+
+static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
+ struct iucv_path *path,
+ struct iucv_message *msg)
+{
+ int rc;
+
+ if (msg->flags & IPRMDATA) {
+ skb->data = NULL;
+ skb->len = 0;
+ } else {
+ rc = iucv_message_receive(path, msg, 0, skb->data,
+ msg->length, NULL);
+ if (rc) {
+ kfree_skb(skb);
+ return;
+ }
+ if (skb->truesize >= sk->sk_rcvbuf / 4) {
+ rc = iucv_fragment_skb(sk, skb, msg->length);
+ kfree_skb(skb);
+ skb = NULL;
+ if (rc) {
+ iucv_path_sever(path, NULL);
+ return;
+ }
+ skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
+ } else {
+ skb_reset_transport_header(skb);
+ skb_reset_network_header(skb);
+ skb->len = msg->length;
+ }
+ }
+
+ if (sock_queue_rcv_skb(sk, skb))
+ skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
+}
+
+static void iucv_process_message_q(struct sock *sk)
+{
+ struct iucv_sock *iucv = iucv_sk(sk);
+ struct sk_buff *skb;
+ struct sock_msg_q *p, *n;
+
+ list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
+ skb = alloc_skb(p->msg.length, GFP_ATOMIC | GFP_DMA);
+ if (!skb)
+ break;
+ iucv_process_message(sk, skb, p->path, &p->msg);
+ list_del(&p->list);
+ kfree(p);
+ if (!skb_queue_empty(&iucv->backlog_skb_q))
+ break;
+ }
+}
+
static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len, int flags)
{
@@ -684,8 +770,9 @@ static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
int err = 0;
if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
- skb_queue_empty(&iucv->backlog_skb_q) &&
- skb_queue_empty(&sk->sk_receive_queue))
+ skb_queue_empty(&iucv->backlog_skb_q) &&
+ skb_queue_empty(&sk->sk_receive_queue) &&
+ list_empty(&iucv->message_q.list))
return 0;
if (flags & (MSG_OOB))
@@ -724,16 +811,23 @@ static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
kfree_skb(skb);
/* Queue backlog skbs */
- rskb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
+ rskb = skb_dequeue(&iucv->backlog_skb_q);
while (rskb) {
if (sock_queue_rcv_skb(sk, rskb)) {
- skb_queue_head(&iucv_sk(sk)->backlog_skb_q,
+ skb_queue_head(&iucv->backlog_skb_q,
rskb);
break;
} else {
- rskb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
+ rskb = skb_dequeue(&iucv->backlog_skb_q);
}
}
+ if (skb_queue_empty(&iucv->backlog_skb_q)) {
+ spin_lock_bh(&iucv->message_q.lock);
+ if (!list_empty(&iucv->message_q.list))
+ iucv_process_message_q(sk);
+ spin_unlock_bh(&iucv->message_q.lock);
+ }
+
} else
skb_queue_head(&sk->sk_receive_queue, skb);
@@ -975,99 +1069,44 @@ static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
sk->sk_state_change(sk);
}
-static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len,
- struct sk_buff_head *fragmented_skb_q)
-{
- int dataleft, size, copied = 0;
- struct sk_buff *nskb;
-
- dataleft = len;
- while (dataleft) {
- if (dataleft >= sk->sk_rcvbuf / 4)
- size = sk->sk_rcvbuf / 4;
- else
- size = dataleft;
-
- nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
- if (!nskb)
- return -ENOMEM;
-
- memcpy(nskb->data, skb->data + copied, size);
- copied += size;
- dataleft -= size;
-
- skb_reset_transport_header(nskb);
- skb_reset_network_header(nskb);
- nskb->len = size;
-
- skb_queue_tail(fragmented_skb_q, nskb);
- }
-
- return 0;
-}
-
static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
{
struct sock *sk = path->private;
struct iucv_sock *iucv = iucv_sk(sk);
- struct sk_buff *skb, *fskb;
- struct sk_buff_head fragmented_skb_q;
- int rc;
-
- skb_queue_head_init(&fragmented_skb_q);
+ struct sk_buff *skb;
+ struct sock_msg_q *save_msg;
+ int len;
if (sk->sk_shutdown & RCV_SHUTDOWN)
return;
+ if (!list_empty(&iucv->message_q.list) ||
+ !skb_queue_empty(&iucv->backlog_skb_q))
+ goto save_message;
+
+ len = atomic_read(&sk->sk_rmem_alloc);
+ len += msg->length + sizeof(struct sk_buff);
+ if (len > sk->sk_rcvbuf)
+ goto save_message;
+
skb = alloc_skb(msg->length, GFP_ATOMIC | GFP_DMA);
- if (!skb) {
- iucv_path_sever(path, NULL);
- return;
- }
+ if (!skb)
+ goto save_message;
- if (msg->flags & IPRMDATA) {
- skb->data = NULL;
- skb->len = 0;
- } else {
- rc = iucv_message_receive(path, msg, 0, skb->data,
- msg->length, NULL);
- if (rc) {
- kfree_skb(skb);
- return;
- }
- if (skb->truesize >= sk->sk_rcvbuf / 4) {
- rc = iucv_fragment_skb(sk, skb, msg->length,
- &fragmented_skb_q);
- kfree_skb(skb);
- skb = NULL;
- if (rc) {
- iucv_path_sever(path, NULL);
- return;
- }
- } else {
- skb_reset_transport_header(skb);
- skb_reset_network_header(skb);
- skb->len = msg->length;
- }
- }
- /* Queue the fragmented skb */
- fskb = skb_dequeue(&fragmented_skb_q);
- while (fskb) {
- if (!skb_queue_empty(&iucv->backlog_skb_q))
- skb_queue_tail(&iucv->backlog_skb_q, fskb);
- else if (sock_queue_rcv_skb(sk, fskb))
- skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, fskb);
- fskb = skb_dequeue(&fragmented_skb_q);
- }
+ spin_lock(&iucv->message_q.lock);
+ iucv_process_message(sk, skb, path, msg);
+ spin_unlock(&iucv->message_q.lock);
- /* Queue the original skb if it exists (was not fragmented) */
- if (skb) {
- if (!skb_queue_empty(&iucv->backlog_skb_q))
- skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
- else if (sock_queue_rcv_skb(sk, skb))
- skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
- }
+ return;
+
+save_message:
+ save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
+ save_msg->path = path;
+ save_msg->msg = *msg;
+ spin_lock(&iucv->message_q.lock);
+ list_add_tail(&save_msg->list, &iucv->message_q.list);
+ spin_unlock(&iucv->message_q.lock);
}
static void iucv_callback_txdone(struct iucv_path *path,

Privacy Policy