dccp: Policy-based packet dequeueing infrastructure
This patch adds a generic infrastructure for policy-based dequeueing of
TX packets and provides two policies:
* a simple FIFO policy (which is the default) and
* a priority based policy (set via socket options).
Both policies honour the tx_qlen sysctl for the maximum size of the write
queue (can be overridden via socket options).
The priority policy uses skb->priority internally to assign an u32 priority
identifier, using the same ranking as SO_PRIORITY. The skb->priority field
is set to 0 when the packet leaves DCCP. The priority is supplied as ancillary
data using cmsg(3), the patch also provides the requisite parsing routines.
Signed-off-by: Tomasz Grobelny <tomasz@grobelny.oswiecenia.net>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
diff --git a/net/dccp/output.c b/net/dccp/output.c
index d96dd9d..784d3021 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -242,7 +242,7 @@
{
int err, len;
struct dccp_sock *dp = dccp_sk(sk);
- struct sk_buff *skb = skb_dequeue(&sk->sk_write_queue);
+ struct sk_buff *skb = dccp_qpolicy_pop(sk);
if (unlikely(skb == NULL))
return;
@@ -345,7 +345,7 @@
struct dccp_sock *dp = dccp_sk(sk);
struct sk_buff *skb;
- while ((skb = skb_peek(&sk->sk_write_queue))) {
+ while ((skb = dccp_qpolicy_top(sk))) {
int rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
switch (ccid_packet_dequeue_eval(rc)) {
@@ -359,8 +359,7 @@
dccp_xmit_packet(sk);
break;
case CCID_PACKET_ERR:
- skb_dequeue(&sk->sk_write_queue);
- kfree_skb(skb);
+ dccp_qpolicy_drop(sk, skb);
dccp_pr_debug("packet discarded due to err=%d\n", rc);
}
}