[DCCP] Introduce dccp_timestamp

To start the timestamps with 0.0ms, easing the integer maths in the CCIDs, this
probably will be reworked to use the to be introduced struct timeval_offset
infrastructure out of skb_get_timestamp, etc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

9 files changed, 61 insertions, 39 deletions

diff --git a/include/linux/dccp.h b/include/linux/dccp.h
index 5e0af0d08a93..8bf4bacb5051 100644
--- a/include/linux/dccp.h
+++ b/include/linux/dccp.h
@@ -432,6 +432,7 @@ struct dccp_sock {
         struct ccid                     *dccps_hc_rx_ccid;
         struct ccid                     *dccps_hc_tx_ccid;
         struct dccp_options_received    dccps_options_received;
+        struct timeval                  dccps_epoch;
         enum dccp_role                  dccps_role:2;
         __u8                            dccps_hc_rx_insert_options:1;
         __u8                            dccps_hc_tx_insert_options:1;
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index 145aafafe4e2..348e6fb262c3 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -169,7 +169,7 @@ static void ccid3_hc_tx_update_x(struct sock *sk)
         } else {
                 struct timeval now;
 
-                do_gettimeofday(&now);
+                dccp_timestamp(sk, &now);
                 if (timeval_delta(&now, &hctx->ccid3hctx_t_ld) >=
                     hctx->ccid3hctx_rtt) {
                         hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_recv,
@@ -317,7 +317,7 @@ static int ccid3_hc_tx_send_packet(struct sock *sk,
                 dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, new_packet);
         }
 
-        do_gettimeofday(&now);
+        dccp_timestamp(sk, &now);
 
         switch (hctx->ccid3hctx_state) {
         case TFRC_SSTATE_NO_SENT:
@@ -382,7 +382,7 @@ static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len)
                 return;
         }
 
-        do_gettimeofday(&now);
+        dccp_timestamp(sk, &now);
 
         /* check if we have sent a data packet */
         if (len > 0) {
@@ -461,6 +461,7 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
         struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
         struct ccid3_options_received *opt_recv;
         struct dccp_tx_hist_entry *packet;
+        struct timeval now;
         unsigned long next_tmout; 
         u32 t_elapsed;
         u32 pinv;
@@ -508,7 +509,8 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
                 }
 
                 /* Update RTT */
-                r_sample = timeval_now_delta(&packet->dccphtx_tstamp);
+                dccp_timestamp(sk, &now);
+                r_sample = timeval_delta(&now, &packet->dccphtx_tstamp);
                 if (unlikely(r_sample <= t_elapsed))
                         LIMIT_NETDEBUG(KERN_WARNING
                                        "%s: r_sample=%uus, t_elapsed=%uus\n",
@@ -774,7 +776,7 @@ static void ccid3_hc_rx_send_feedback(struct sock *sk)
 
         ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
 
-        do_gettimeofday(&now);
+        dccp_timestamp(sk, &now);
 
         switch (hcrx->ccid3hcrx_state) {
         case TFRC_RSTATE_NO_DATA:
@@ -903,10 +905,9 @@ found:
         if (rtt == 0)
                 rtt = 1;
 
-        delta = timeval_now_delta(&hcrx->ccid3hcrx_tstamp_last_feedback);
-        x_recv = hcrx->ccid3hcrx_bytes_recv * USEC_PER_SEC;
-        if (likely(delta > 1))
-                x_recv /= delta;
+        dccp_timestamp(sk, &tstamp);
+        delta = timeval_delta(&tstamp, &hcrx->ccid3hcrx_tstamp_last_feedback);
+        x_recv = usecs_div(hcrx->ccid3hcrx_bytes_recv, delta);
 
         tmp1 = (u64)x_recv * (u64)rtt;
         do_div(tmp1,10000000);
@@ -981,7 +982,7 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
                 if (opt_recv->dccpor_timestamp_echo == 0)
                         break;
                 p_prev = hcrx->ccid3hcrx_rtt;
-                do_gettimeofday(&now);
+                dccp_timestamp(sk, &now);
                 timeval_sub_usecs(&now, opt_recv->dccpor_timestamp_echo * 10);
                 r_sample = timeval_usecs(&now);
                 t_elapsed = opt_recv->dccpor_elapsed_time * 10;
@@ -1013,7 +1014,7 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
                 return;
         }
 
-        packet = dccp_rx_hist_entry_new(ccid3_rx_hist, opt_recv->dccpor_ndp,
+        packet = dccp_rx_hist_entry_new(ccid3_rx_hist, sk, opt_recv->dccpor_ndp,
                                         skb, SLAB_ATOMIC);
         if (packet == NULL) {
                 ccid3_pr_debug("%s, sk=%p, Not enough mem to add rx packet "
@@ -1045,7 +1046,7 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
                 if (ins != 0)
                         break;
 
-                do_gettimeofday(&now);
+                dccp_timestamp(sk, &now);
                 if (timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) >=
                     hcrx->ccid3hcrx_rtt) {
                         hcrx->ccid3hcrx_tstamp_last_ack = now;
@@ -1100,7 +1101,7 @@ static int ccid3_hc_rx_init(struct sock *sk)
         hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA;
         INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist);
         INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist);
-        do_gettimeofday(&hcrx->ccid3hcrx_tstamp_last_ack);
+        dccp_timestamp(sk, &hcrx->ccid3hcrx_tstamp_last_ack);
         hcrx->ccid3hcrx_tstamp_last_feedback = hcrx->ccid3hcrx_tstamp_last_ack;
         hcrx->ccid3hcrx_rtt = 5000; /* XXX 5ms for now... */
         return 0;
diff --git a/net/dccp/ccids/ccid3.h b/net/dccp/ccids/ccid3.h
index ee8cbace6630..58be6125b695 100644
--- a/net/dccp/ccids/ccid3.h
+++ b/net/dccp/ccids/ccid3.h
@@ -115,7 +115,7 @@ struct ccid3_hc_rx_sock {
         u64                     ccid3hcrx_seqno_last_counter:48,
                                 ccid3hcrx_state:8,
                                 ccid3hcrx_last_counter:4;
-        unsigned long           ccid3hcrx_rtt;
+        u32                     ccid3hcrx_rtt;
         u32                     ccid3hcrx_p;
         u32                     ccid3hcrx_bytes_recv;
         struct timeval          ccid3hcrx_tstamp_last_feedback;
diff --git a/net/dccp/ccids/lib/packet_history.h b/net/dccp/ccids/lib/packet_history.h
index fb90a91aa93d..b375ebdb7dcf 100644
--- a/net/dccp/ccids/lib/packet_history.h
+++ b/net/dccp/ccids/lib/packet_history.h
@@ -134,6 +134,7 @@ static inline struct dccp_tx_hist_entry *
 
 static inline struct dccp_rx_hist_entry *
                      dccp_rx_hist_entry_new(struct dccp_rx_hist *hist,
+                                            const struct sock *sk, 
                                             const u32 ndp, 
                                             const struct sk_buff *skb,
                                             const unsigned int __nocast prio)
@@ -148,7 +149,7 @@ static inline struct dccp_rx_hist_entry *
                 entry->dccphrx_ccval = dh->dccph_ccval;