dccp: do not use tcp_time_stamp

Use our own macro instead of abusing tcp_time_stamp
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/dccp/ccids/ccid2.c

@@ -233,7 +233,7 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, unsigned int len)
 {
 	struct dccp_sock *dp = dccp_sk(sk);
 	struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk);
-	const u32 now = ccid2_time_stamp;
+	const u32 now = ccid2_jiffies32;
 	struct ccid2_seq *next;
 
 	/* slow-start after idle periods (RFC 2581, RFC 2861) */
@@ -466,7 +466,7 @@ static void ccid2_new_ack(struct sock *sk, struct ccid2_seq *seqp,
 	 * The cleanest solution is to not use the ccid2s_sent field at all
 	 * and instead use DCCP timestamps: requires changes in other places.
 	 */
-	ccid2_rtt_estimator(sk, ccid2_time_stamp - seqp->ccid2s_sent);
+	ccid2_rtt_estimator(sk, ccid2_jiffies32 - seqp->ccid2s_sent);
 }
 
 static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp)
@@ -478,7 +478,7 @@ static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp)
 		return;
 	}
 
-	hc->tx_last_cong = ccid2_time_stamp;
+	hc->tx_last_cong = ccid2_jiffies32;
 
 	hc->tx_cwnd      = hc->tx_cwnd / 2 ? : 1U;
 	hc->tx_ssthresh  = max(hc->tx_cwnd, 2U);
@@ -731,7 +731,7 @@ static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk)
 
 	hc->tx_rto	 = DCCP_TIMEOUT_INIT;
 	hc->tx_rpdupack  = -1;
-	hc->tx_last_cong = hc->tx_lsndtime = hc->tx_cwnd_stamp = ccid2_time_stamp;
+	hc->tx_last_cong = hc->tx_lsndtime = hc->tx_cwnd_stamp = ccid2_jiffies32;
 	hc->tx_cwnd_used = 0;
 	setup_timer(&hc->tx_rtotimer, ccid2_hc_tx_rto_expire,
 			(unsigned long)sk);

net/dccp/ccids/ccid2.h

@@ -27,7 +27,7 @@
  * CCID-2 timestamping faces the same issues as TCP timestamping.
  * Hence we reuse/share as much of the code as possible.
  */
-#define ccid2_time_stamp	tcp_time_stamp
+#define ccid2_jiffies32	((u32)jiffies)
 
 /* NUMDUPACK parameter from RFC 4341, p. 6 */
 #define NUMDUPACK	3