From 9108d5f4b2cd82f55ad178caa0be66a866a06dcc Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 29 Nov 2007 22:47:15 -0200 Subject: [PATCH] [TFRC]: Hide tx history details from the CCIDs Based on a previous patch by Gerrit Renker. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/dccp/ccids/ccid3.c | 19 ++++++----------- net/dccp/ccids/lib/packet_history.c | 33 +++++++++++++++++++++++++++-- net/dccp/ccids/lib/packet_history.h | 17 +++------------ 3 files changed, 41 insertions(+), 28 deletions(-) diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index f73542ab9d08..49338370eb04 100644 --- 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 139736064713..4805de996568 100644 --- a/net/dccp/ccids/lib/packet_history.c +++ b/net/dccp/ccids/lib/packet_history.c @@ -39,12 +39,24 @@ #include #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 5c07182dd659..0670f46dd53c 100644 --- 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