diff options
Diffstat (limited to 'net/dccp/ccids/lib')
-rw-r--r-- | net/dccp/ccids/lib/loss_interval.c | 10 | ||||
-rw-r--r-- | net/dccp/ccids/lib/packet_history.c | 103 | ||||
-rw-r--r-- | net/dccp/ccids/lib/packet_history.h | 30 |
3 files changed, 61 insertions, 82 deletions
diff --git a/net/dccp/ccids/lib/loss_interval.c b/net/dccp/ccids/lib/loss_interval.c index 849e181..bcd6ac4 100644 --- a/net/dccp/ccids/lib/loss_interval.c +++ b/net/dccp/ccids/lib/loss_interval.c @@ -90,14 +90,14 @@ u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb) { struct tfrc_loss_interval *cur = tfrc_lh_peek(lh); u32 old_i_mean = lh->i_mean; - s64 length; + s64 len; if (cur == NULL) /* not initialised */ return 0; - length = dccp_delta_seqno(cur->li_seqno, DCCP_SKB_CB(skb)->dccpd_seq); + len = dccp_delta_seqno(cur->li_seqno, DCCP_SKB_CB(skb)->dccpd_seq) + 1; - if (length - cur->li_length <= 0) /* duplicate or reordered */ + if (len - (s64)cur->li_length <= 0) /* duplicate or reordered */ return 0; if (SUB16(dccp_hdr(skb)->dccph_ccval, cur->li_ccval) > 4) @@ -114,7 +114,7 @@ u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb) if (tfrc_lh_length(lh) == 1) /* due to RFC 3448, 6.3.1 */ return 0; - cur->li_length = length; + cur->li_length = len; tfrc_lh_calc_i_mean(lh); return (lh->i_mean < old_i_mean); @@ -159,7 +159,7 @@ int tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh, else { cur->li_length = dccp_delta_seqno(cur->li_seqno, new->li_seqno); new->li_length = dccp_delta_seqno(new->li_seqno, - tfrc_rx_hist_last_rcv(rh)->tfrchrx_seqno); + tfrc_rx_hist_last_rcv(rh)->tfrchrx_seqno) + 1; if (lh->counter > (2*LIH_SIZE)) lh->counter -= LIH_SIZE; diff --git a/net/dccp/ccids/lib/packet_history.c b/net/dccp/ccids/lib/packet_history.c index 20af1a6..6cc108a 100644 --- a/net/dccp/ccids/lib/packet_history.c +++ b/net/dccp/ccids/lib/packet_history.c @@ -153,7 +153,7 @@ void tfrc_rx_packet_history_exit(void) static inline void tfrc_rx_hist_entry_from_skb(struct tfrc_rx_hist_entry *entry, const struct sk_buff *skb, - const u32 ndp) + const u64 ndp) { const struct dccp_hdr *dh = dccp_hdr(skb); @@ -166,7 +166,7 @@ static inline void tfrc_rx_hist_entry_from_skb(struct tfrc_rx_hist_entry *entry, void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h, const struct sk_buff *skb, - const u32 ndp) + const u64 ndp) { struct tfrc_rx_hist_entry *entry = tfrc_rx_hist_last_rcv(h); @@ -206,31 +206,39 @@ static void tfrc_rx_hist_swap(struct tfrc_rx_hist *h, const u8 a, const u8 b) * * In the descriptions, `Si' refers to the sequence number of entry number i, * whose NDP count is `Ni' (lower case is used for variables). - * Note: All __after_loss functions expect that a test against duplicates has - * been performed already: the seqno of the skb must not be less than the - * seqno of loss_prev; and it must not equal that of any valid hist_entry. + * Note: All __xxx_loss functions expect that a test against duplicates has been + * performed already: the seqno of the skb must not be less than the seqno + * of loss_prev; and it must not equal that of any valid history entry. */ +static void __do_track_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u64 n1) +{ + u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno, + s1 = DCCP_SKB_CB(skb)->dccpd_seq; + + if (!dccp_loss_free(s0, s1, n1)) { /* gap between S0 and S1 */ + h->loss_count = 1; + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 1), skb, n1); + } +} + static void __one_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n2) { u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno, s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno, s2 = DCCP_SKB_CB(skb)->dccpd_seq; - int n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp, - d12 = dccp_delta_seqno(s1, s2), d2; - if (d12 > 0) { /* S1 < S2 */ + if (likely(dccp_delta_seqno(s1, s2) > 0)) { /* S1 < S2 */ h->loss_count = 2; tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 2), skb, n2); return; } /* S0 < S2 < S1 */ - d2 = dccp_delta_seqno(s0, s2); - if (d2 == 1 || n2 >= d2) { /* S2 is direct successor of S0 */ - int d21 = -d12; + if (dccp_loss_free(s0, s2, n2)) { + u64 n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp; - if (d21 == 1 || n1 >= d21) { + if (dccp_loss_free(s2, s1, n1)) { /* hole is filled: S0, S2, and S1 are consecutive */ h->loss_count = 0; h->loss_start = tfrc_rx_hist_index(h, 1); @@ -238,9 +246,9 @@ static void __one_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n2 /* gap between S2 and S1: just update loss_prev */ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_loss_prev(h), skb, n2); - } else { /* hole between S0 and S2 */ + } else { /* gap between S0 and S2 */ /* - * Reorder history to insert S2 between S0 and s1 + * Reorder history to insert S2 between S0 and S1 */ tfrc_rx_hist_swap(h, 0, 3); h->loss_start = tfrc_rx_hist_index(h, 3); @@ -256,22 +264,18 @@ static int __two_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n3) s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno, s2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_seqno, s3 = DCCP_SKB_CB(skb)->dccpd_seq; - int n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp, - d23 = dccp_delta_seqno(s2, s3), d13, d3, d31; - if (d23 > 0) { /* S2 < S3 */ + if (likely(dccp_delta_seqno(s2, s3) > 0)) { /* S2 < S3 */ h->loss_count = 3; tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 3), skb, n3); return 1; } /* S3 < S2 */ - d13 = dccp_delta_seqno(s1, s3); - if (d13 > 0) { + if (dccp_delta_seqno(s1, s3) > 0) { /* S1 < S3 < S2 */ /* - * The sequence number order is S1, S3, S2 - * Reorder history to insert entry between S1 and S2 + * Reorder history to insert S3 between S1 and S2 */ tfrc_rx_hist_swap(h, 2, 3); tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 2), skb, n3); @@ -280,17 +284,15 @@ static int __two_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n3) } /* S0 < S3 < S1 */ - d31 = -d13; - d3 = dccp_delta_seqno(s0, s3); - if (d3 == 1 || n3 >= d3) { /* S3 is a successor of S0 */ + if (dccp_loss_free(s0, s3, n3)) { + u64 n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp; - if (d31 == 1 || n1 >= d31) { + if (dccp_loss_free(s3, s1, n1)) { /* hole between S0 and S1 filled by S3 */ - int d2 = dccp_delta_seqno(s1, s2), - n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp; + u64 n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp; - if (d2 == 1 || n2 >= d2) { + if (dccp_loss_free(s1, s2, n2)) { /* entire hole filled by S0, S3, S1, S2 */ h->loss_start = tfrc_rx_hist_index(h, 2); h->loss_count = 0; @@ -307,8 +309,8 @@ static int __two_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n3) } /* - * The remaining case: S3 is not a successor of S0. - * Sequence order is S0, S3, S1, S2; reorder to insert between S0 and S1 + * The remaining case: S0 < S3 < S1 < S2; gap between S0 and S3 + * Reorder history to insert S3 between S0 and S1. */ tfrc_rx_hist_swap(h, 0, 3); h->loss_start = tfrc_rx_hist_index(h, 3); @@ -318,33 +320,25 @@ static int __two_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n3) return 1; } -/* return the signed modulo-2^48 sequence number distance from entry e1 to e2 */ -static s64 tfrc_rx_hist_delta_seqno(struct tfrc_rx_hist *h, u8 e1, u8 e2) -{ - DCCP_BUG_ON(e1 > h->loss_count || e2 > h->loss_count); - - return dccp_delta_seqno(tfrc_rx_hist_entry(h, e1)->tfrchrx_seqno, - tfrc_rx_hist_entry(h, e2)->tfrchrx_seqno); -} - /* recycle RX history records to continue loss detection if necessary */ static void __three_after_loss(struct tfrc_rx_hist *h) { /* - * The distance between S0 and S1 is always greater than 1 and the NDP - * count of S1 is smaller than this distance. Otherwise there would - * have been no loss. Hence it is only necessary to see whether there - * are further missing data packets between S1/S2 and S2/S3. + * At this stage we know already that there is a gap between S0 and S1 + * (since S0 was the highest sequence number received before detecting + * the loss). To recycle the loss record, it is thus only necessary to + * check for other possible gaps between S1/S2 and between S2/S3. */ - int d2 = tfrc_rx_hist_delta_seqno(h, 1, 2), - d3 = tfrc_rx_hist_delta_seqno(h, 2, 3), - n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp, + u64 s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno, + s2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_seqno, + s3 = tfrc_rx_hist_entry(h, 3)->tfrchrx_seqno; + u64 n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp, n3 = tfrc_rx_hist_entry(h, 3)->tfrchrx_ndp; - if (d2 == 1 || n2 >= d2) { /* S2 is successor to S1 */ + if (dccp_loss_free(s1, s2, n2)) { - if (d3 == 1 || n3 >= d3) { - /* S3 is successor of S2: entire hole is filled */ + if (dccp_loss_free(s2, s3, n3)) { + /* no gap between S2 and S3: entire hole is filled */ h->loss_start = tfrc_rx_hist_index(h, 3); h->loss_count = 0; } else { @@ -353,7 +347,7 @@ static void __three_after_loss(struct tfrc_rx_hist *h) h->loss_count = 1; } - } else { /* gap between S1 and S2 */ + } else { /* gap between S1 and S2 */ h->loss_start = tfrc_rx_hist_index(h, 1); h->loss_count = 2; } @@ -370,15 +364,20 @@ static void __three_after_loss(struct tfrc_rx_hist *h) * Chooses action according to pending loss, updates LI database when a new * loss was detected, and does required post-processing. Returns 1 when caller * should send feedback, 0 otherwise. + * Since it also takes care of reordering during loss detection and updates the + * records accordingly, the caller should not perform any more RX history + * operations when loss_count is greater than 0 after calling this function. */ int tfrc_rx_handle_loss(struct tfrc_rx_hist *h, struct tfrc_loss_hist *lh, - struct sk_buff *skb, u32 ndp, + struct sk_buff *skb, const u64 ndp, u32 (*calc_first_li)(struct sock *), struct sock *sk) { int is_new_loss = 0; - if (h->loss_count == 1) { + if (h->loss_count == 0) { + __do_track_loss(h, skb, ndp); + } else if (h->loss_count == 1) { __one_after_loss(h, skb, ndp); } else if (h->loss_count != 2) { DCCP_BUG("invalid loss_count %d", h->loss_count); diff --git a/net/dccp/ccids/lib/packet_history.h b/net/dccp/ccids/lib/packet_history.h index c7eeda4..461cc91 100644 --- a/net/dccp/ccids/lib/packet_history.h +++ b/net/dccp/ccids/lib/packet_history.h @@ -64,7 +64,7 @@ struct tfrc_rx_hist_entry { u64 tfrchrx_seqno:48, tfrchrx_ccval:4, tfrchrx_type:4; - u32 tfrchrx_ndp; /* In fact it is from 8 to 24 bits */ + u64 tfrchrx_ndp:48; ktime_t tfrchrx_tstamp; }; @@ -118,41 +118,21 @@ static inline struct tfrc_rx_hist_entry * return h->ring[h->loss_start]; } -/* initialise loss detection and disable RTT sampling */ -static inline void tfrc_rx_hist_loss_indicated(struct tfrc_rx_hist *h) -{ - h->loss_count = 1; -} - /* indicate whether previously a packet was detected missing */ -static inline int tfrc_rx_hist_loss_pending(const struct tfrc_rx_hist *h) -{ - return h->loss_count; -} - -/* any data packets missing between last reception and skb ? */ -static inline int tfrc_rx_hist_new_loss_indicated(struct tfrc_rx_hist *h, - const struct sk_buff *skb, - u32 ndp) +static inline bool tfrc_rx_hist_loss_pending(const struct tfrc_rx_hist *h) { - int delta = dccp_delta_seqno(tfrc_rx_hist_last_rcv(h)->tfrchrx_seqno, - DCCP_SKB_CB(skb)->dccpd_seq); - - if (delta > 1 && ndp < delta) - tfrc_rx_hist_loss_indicated(h); - - return tfrc_rx_hist_loss_pending(h); + return h->loss_count > 0; } extern void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h, - const struct sk_buff *skb, const u32 ndp); + const struct sk_buff *skb, const u64 ndp); extern int tfrc_rx_hist_duplicate(struct tfrc_rx_hist *h, struct sk_buff *skb); struct tfrc_loss_hist; extern int tfrc_rx_handle_loss(struct tfrc_rx_hist *h, struct tfrc_loss_hist *lh, - struct sk_buff *skb, u32 ndp, + struct sk_buff *skb, const u64 ndp, u32 (*first_li)(struct sock *sk), struct sock *sk); extern u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h, |