openwrt/target/linux/generic/backport-4.9/024-1-tcp-tsq-add-tsq_flags-tsq_enum.patch

From 40fc3423b983b864bf70b03199191260ae9b2ea6 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Sat, 3 Dec 2016 11:14:50 -0800
Subject: [PATCH 01/10] tcp: tsq: add tsq_flags / tsq_enum

This is a cleanup, to ease code review of following patches.

Old 'enum tsq_flags' is renamed, and a new enumeration is added
with the flags used in cmpxchg() operations as opposed to
single bit operations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 include/linux/tcp.h   | 11 ++++++++++-
 net/ipv4/tcp_output.c | 16 ++++++++--------
 2 files changed, 18 insertions(+), 9 deletions(-)

--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -368,7 +368,7 @@ struct tcp_sock {
 	u32	*saved_syn;
 };
 
-enum tsq_flags {
+enum tsq_enum {
 	TSQ_THROTTLED,
 	TSQ_QUEUED,
 	TCP_TSQ_DEFERRED,	   /* tcp_tasklet_func() found socket was owned */
@@ -379,6 +379,15 @@ enum tsq_flags {
 				    */
 };
 
+enum tsq_flags {
+	TSQF_THROTTLED			= (1UL << TSQ_THROTTLED),
+	TSQF_QUEUED			= (1UL << TSQ_QUEUED),
+	TCPF_TSQ_DEFERRED		= (1UL << TCP_TSQ_DEFERRED),
+	TCPF_WRITE_TIMER_DEFERRED	= (1UL << TCP_WRITE_TIMER_DEFERRED),
+	TCPF_DELACK_TIMER_DEFERRED	= (1UL << TCP_DELACK_TIMER_DEFERRED),
+	TCPF_MTU_REDUCED_DEFERRED	= (1UL << TCP_MTU_REDUCED_DEFERRED),
+};
+
 static inline struct tcp_sock *tcp_sk(const struct sock *sk)
 {
 	return (struct tcp_sock *)sk;
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -789,10 +789,10 @@ static void tcp_tasklet_func(unsigned lo
 	}
 }
 
-#define TCP_DEFERRED_ALL ((1UL << TCP_TSQ_DEFERRED) |		\
-			  (1UL << TCP_WRITE_TIMER_DEFERRED) |	\
-			  (1UL << TCP_DELACK_TIMER_DEFERRED) |	\
-			  (1UL << TCP_MTU_REDUCED_DEFERRED))
+#define TCP_DEFERRED_ALL (TCPF_TSQ_DEFERRED |		\
+			  TCPF_WRITE_TIMER_DEFERRED |	\
+			  TCPF_DELACK_TIMER_DEFERRED |	\
+			  TCPF_MTU_REDUCED_DEFERRED)
 /**
  * tcp_release_cb - tcp release_sock() callback
  * @sk: socket
@@ -813,7 +813,7 @@ void tcp_release_cb(struct sock *sk)
 		nflags = flags & ~TCP_DEFERRED_ALL;
 	} while (cmpxchg(&tp->tsq_flags, flags, nflags) != flags);
 
-	if (flags & (1UL << TCP_TSQ_DEFERRED))
+	if (flags & TCPF_TSQ_DEFERRED)
 		tcp_tsq_handler(sk);
 
 	/* Here begins the tricky part :
@@ -827,15 +827,15 @@ void tcp_release_cb(struct sock *sk)
 	 */
 	sock_release_ownership(sk);
 
-	if (flags & (1UL << TCP_WRITE_TIMER_DEFERRED)) {
+	if (flags & TCPF_WRITE_TIMER_DEFERRED) {
 		tcp_write_timer_handler(sk);
 		__sock_put(sk);
 	}
-	if (flags & (1UL << TCP_DELACK_TIMER_DEFERRED)) {
+	if (flags & TCPF_DELACK_TIMER_DEFERRED) {
 		tcp_delack_timer_handler(sk);
 		__sock_put(sk);
 	}
-	if (flags & (1UL << TCP_MTU_REDUCED_DEFERRED)) {
+	if (flags & TCPF_MTU_REDUCED_DEFERRED) {
 		inet_csk(sk)->icsk_af_ops->mtu_reduced(sk);
 		__sock_put(sk);
 	}