tcp: remove TCP_SKB_CB(skb)->when

After commit 740b0f1841f6 ("tcp: switch rtt estimations to usec resolution"),
we no longer need to maintain timestamps in two different fields.

TCP_SKB_CB(skb)->when can be removed, as same information sits in skb_mstamp.stamp_jiffies

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 0cd7d2c..a4201ef 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -672,6 +672,12 @@ void tcp_send_window_probe(struct sock *sk);
  */
 #define tcp_time_stamp         ((__u32)(jiffies))
 
+static inline u32 tcp_skb_timestamp(const struct sk_buff *skb)
+{
+       return skb->skb_mstamp.stamp_jiffies;
+}
+
+
 #define tcp_flag_byte(th) (((u_int8_t *)th)[13])
 
 #define TCPHDR_FIN 0x01
@@ -698,12 +704,7 @@ struct tcp_skb_cb {
        } header;       /* For incoming frames          */
        __u32           seq;            /* Starting sequence number     */
        __u32           end_seq;        /* SEQ + FIN + SYN + datalen    */
-       union {
-               /* used in output path */
-               __u32           when;   /* used to compute rtt's        */
-               /* used in input path */
-               __u32           tcp_tw_isn; /* isn chosen by tcp_timewait_state_process() */
-       };
+       __u32           tcp_tw_isn;     /* isn chosen by tcp_timewait_state_process() */
        __u8            tcp_flags;      /* TCP header flags. (tcp[13])  */
 
        __u8            sacked;         /* State flags for SACK/FACK.   */

diff --cc net/ipv4/tcp_input.c
Simple merge

diff --cc net/ipv4/tcp_ipv4.c
Simple merge

diff --cc net/ipv4/tcp_output.c
Simple merge

diff --cc net/ipv4/tcp_timer.c
Simple merge