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/dccp.h b/net/dccp/dccp.h
index 19fafd5..d008da9 100644
--- a/net/dccp/dccp.h
+++ b/net/dccp/dccp.h
@@ -243,6 +243,18 @@
extern void dccp_send_sync(struct sock *sk, const u64 seq,
const enum dccp_pkt_type pkt_type);
+/*
+ * TX Packet Dequeueing Interface
+ */
+extern void dccp_qpolicy_push(struct sock *sk, struct sk_buff *skb);
+extern bool dccp_qpolicy_full(struct sock *sk);
+extern void dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb);
+extern struct sk_buff *dccp_qpolicy_top(struct sock *sk);
+extern struct sk_buff *dccp_qpolicy_pop(struct sock *sk);
+
+/*
+ * TX Packet Output and TX Timers
+ */
extern void dccp_write_xmit(struct sock *sk);
extern void dccp_write_space(struct sock *sk);
extern void dccp_flush_write_queue(struct sock *sk, long *time_budget);