[TFRC]: Hide tx history details from the CCIDs

Based on a previous patch by Gerrit Renker.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index f73542ab9d0853f2678a5d345a7104973a273b2b..49338370eb047c027e172cc63cdb05cb8eef2100 100644 (file)
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -399,7 +399,6 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
 {
        struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
        struct ccid3_options_received *opt_recv;
-       struct tfrc_tx_hist_entry *packet;
        ktime_t now;
        unsigned long t_nfb;
        u32 pinv, r_sample;
@@ -414,19 +413,17 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
        switch (hctx->ccid3hctx_state) {
        case TFRC_SSTATE_NO_FBACK:
        case TFRC_SSTATE_FBACK:
+               now = ktime_get_real();
+
                /* estimate RTT from history if ACK number is valid */
-               packet = tfrc_tx_hist_find_entry(hctx->ccid3hctx_hist,
-                                                DCCP_SKB_CB(skb)->dccpd_ack_seq);
-               if (packet == NULL) {
+               r_sample = tfrc_tx_hist_rtt(hctx->ccid3hctx_hist,
+                                           DCCP_SKB_CB(skb)->dccpd_ack_seq, now);
+               if (r_sample == 0) {
                        DCCP_WARN("%s(%p): %s with bogus ACK-%llu\n", dccp_role(sk), sk,
                                  dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type),
                                  (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq);
                        return;
                }
-               /*
-                * Garbage-collect older (irrelevant) entries
-                */
-               tfrc_tx_hist_purge(&packet->next);
 
                /* Update receive rate in units of 64 * bytes/second */
                hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate;
@@ -438,12 +435,10 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
                        hctx->ccid3hctx_p = 0;
                else                                   /* can not exceed 100% */
                        hctx->ccid3hctx_p = 1000000 / pinv;
-
-               now = ktime_get_real();
                /*
-                * Calculate new RTT sample and update moving average
+                * Validate new RTT sample and update moving average
                 */
-               r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, packet->stamp));
+               r_sample = dccp_sample_rtt(sk, r_sample);
                hctx->ccid3hctx_rtt = tfrc_ewma(hctx->ccid3hctx_rtt, r_sample, 9);
 
                if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {

diff --git a/net/dccp/ccids/lib/packet_history.c b/net/dccp/ccids/lib/packet_history.c
index 1397360647130b30348ed607a9dee3512eb58ad5..4805de9965684bcf74c8ed45a98283e7bf50717a 100644 (file)
--- a/net/dccp/ccids/lib/packet_history.c
+++ b/net/dccp/ccids/lib/packet_history.c
@@ -39,12 +39,24 @@
 #include <linux/string.h>
 #include "packet_history.h"
 
+/**
+ *  tfrc_tx_hist_entry  -  Simple singly-linked TX history list
+ *  @next:  next oldest entry (LIFO order)
+ *  @seqno: sequence number of this entry
+ *  @stamp: send time of packet with sequence number @seqno
+ */
+struct tfrc_tx_hist_entry {
+       struct tfrc_tx_hist_entry *next;
+       u64                       seqno;
+       ktime_t                   stamp;
+};
+
 /*
  * Transmitter History Routines
  */
 static struct kmem_cache *tfrc_tx_hist;
 
-struct tfrc_tx_hist_entry *
+static struct tfrc_tx_hist_entry *
        tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 seqno)
 {
        while (head != NULL && head->seqno != seqno)
@@ -52,7 +64,6 @@ struct tfrc_tx_hist_entry *
 
        return head;
 }
-EXPORT_SYMBOL_GPL(tfrc_tx_hist_find_entry);
 
 int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno)
 {
@@ -83,6 +94,24 @@ void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp)
 }
 EXPORT_SYMBOL_GPL(tfrc_tx_hist_purge);
 
+u32 tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head, const u64 seqno,
+                    const ktime_t now)
+{
+       u32 rtt = 0;
+       struct tfrc_tx_hist_entry *packet = tfrc_tx_hist_find_entry(head, seqno);
+
+       if (packet != NULL) {
+               rtt = ktime_us_delta(now, packet->stamp);
+               /*
+                * Garbage-collect older (irrelevant) entries:
+                */
+               tfrc_tx_hist_purge(&packet->next);
+       }
+
+       return rtt;
+}
+EXPORT_SYMBOL_GPL(tfrc_tx_hist_rtt);
+
 /*
  *     Receiver History Routines
  */

diff --git a/net/dccp/ccids/lib/packet_history.h b/net/dccp/ccids/lib/packet_history.h
index 5c07182dd65972ea736bc79fa69493c59dc8dc9f..0670f46dd53c7649e880874de108511fa470bb3b 100644 (file)
--- a/net/dccp/ccids/lib/packet_history.h
+++ b/net/dccp/ccids/lib/packet_history.h
@@ -48,23 +48,12 @@
 #define TFRC_WIN_COUNT_PER_RTT  4
 #define TFRC_WIN_COUNT_LIMIT   16
 
-/**
- *  tfrc_tx_hist_entry  -  Simple singly-linked TX history list
- *  @next:  next oldest entry (LIFO order)
- *  @seqno: sequence number of this entry
- *  @stamp: send time of packet with sequence number @seqno
- */
-struct tfrc_tx_hist_entry {
-       struct tfrc_tx_hist_entry *next;
-       u64                       seqno;
-       ktime_t                   stamp;
-};
+struct tfrc_tx_hist_entry;
 
 extern int  tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno);
 extern void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp);
-
-extern struct tfrc_tx_hist_entry *
-       tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 ackno);
+extern u32  tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head,
+                            const u64 seqno, const ktime_t now);
 
 /*
  *     Receiver History data structures and declarations