lwn.git/net/dccp/ccids/lib/loss_interval.c, branch v2.6.33.1-rt10

net-next-2.6 [PATCH 1/1] dccp: ccids whitespace-cleanup / CodingStyle

2009-09-15T00:02:54+00:00

No code change, cosmetical changes only: * whitespace cleanup via scripts/cleanfile, * remove self-references to filename at top of files, * fix coding style (extraneous brackets), * fix documentation style (kernel-doc-nano-HOWTO). Thanks are due to Ivo Augusto Calado who raised these issues by submitting good-quality patches. Signed-off-by: Gerrit Renker Signed-off-by: David S. Miller

dccp: Integrate the TFRC library with DCCP

2009-01-05T05:45:33+00:00

This patch integrates the TFRC library, which is a dependency of CCID-3 (and CCID-4), with the new use of CCIDs in the DCCP module. Signed-off-by: Gerrit Renker Signed-off-by: David S. Miller

This reverts "Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/dccp_exp"

2008-09-09T11:27:22+00:00

as it accentally contained the wrong set of patches. These will be submitted separately. Signed-off-by: Gerrit Renker

dccp ccid-3: Update the RX history records in one place

2008-09-04T05:45:42+00:00

This patch is a requirement for enabling ECN support later on. With that change in mind, the following preparations are done: * renamed handle_loss() into congestion_event() since it returns true when a congestion event happens (it will eventually also take care of ECN packets); * lets tfrc_rx_congestion_event() always update the RX history records, since this routine needs to be called for each non-duplicate packet anyway; * made all involved boolean-type functions to have return type `bool'; Updating the RX history records is now only necessary for the packets received up to sending the first feedback. The receiver code becomes again simpler. Signed-off-by: Gerrit Renker

dccp tfrc: Return type of update_i_mean is void

2008-09-04T05:45:41+00:00

This changes the return type of tfrc_lh_update_i_mean() to void, since that function returns always `false'. This is due to len = dccp_delta_seqno(cur->li_seqno, DCCP_SKB_CB(skb)->dccpd_seq) + 1; if (len - (s64)cur->li_length <= 0) /* duplicate or reordered */ return 0; which means that update_i_mean can only increase the length of the open loss interval I_0, and hence the value of I_tot0 (RFC 3448, 5.4). Consequently the test `i_mean < old_i_mean' at the end of the function always evaluates to false. There is no known way by which a loss interval can suddenly become shorter, therefore the return type of the function is changed to void. (That is, under the given circumstances step (3) in RFC 3448, 6.1 will not occur.) Further changes: ---------------- * the function is now called from tfrc_rx_handle_loss, which is equivalent to the previous way of calling from rx_packet_recv (it was called whenever there was no new or pending loss, now it is also updated when there is a pending loss - this increases the accuracy a bit); * added a FIXME to possibly consider NDP counting as per RFC 4342 (this is not implemented yet). Signed-off-by: Gerrit Renker

dccp ccid-3: Replace lazy BUG_ON with condition

2008-09-04T05:45:25+00:00

The BUG_ON(w_tot == 0) only holds if there is no more than 1 loss interval in the loss history. If there is only a single loss interval, the calc_i_mean() routine need in fact not be called (RFC 3448, 6.3.1). Signed-off-by: Gerrit Renker

dccp ccid-3: Length of loss intervals

2008-07-13T10:51:40+00:00

This corrects an error in the computation of the open loss interval I_0: * the interval length is (highest_seqno - start_seqno) + 1 * and not (highest_seqno - start_seqno). This condition was not fully clear in RFC 3448, but reflects the current revision state of rfc3448bis and is also consistent with RFC 4340, 6.1.1. Further changes: ---------------- * variable renamed due to line length constraints; * explicit typecast to `s64' to avoid implicit signed/unsigned casting. Signed-off-by: Gerrit Renker

[TFRC]: Remove previous loss intervals implementation

2008-01-28T22:57:20+00:00

Signed-off-by: Gerrit Renker Signed-off-by: Ian McDonald Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller

[CCID3]: Interface CCID3 code with newer Loss Intervals Database

2008-01-28T22:57:20+00:00

This hooks up the TFRC Loss Interval database with CCID 3 packet reception. In addition, it makes the CCID-specific computation of the first loss interval (which requires access to all the guts of CCID3) local to ccid3.c. The patch also fixes an omission in the DCCP code, that of a default / fallback RTT value (defined in section 3.4 of RFC 4340 as 0.2 sec); while at it, the upper bound of 4 seconds for an RTT sample has been reduced to match the initial TCP RTO value of 3 seconds from[RFC 1122, 4.2.3.1]. Signed-off-by: Gerrit Renker Signed-off-by: Ian McDonald Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller

[TFRC]: Ringbuffer to track loss interval history

2008-01-28T22:57:18+00:00

A ringbuffer-based implementation of loss interval history is easier to maintain, allocate, and update. The `swap' routine to keep the RX history sorted is due to and was written by Arnaldo Carvalho de Melo, simplifying an earlier macro-based variant. Details: * access to the Loss Interval Records via macro wrappers (with safety checks); * simplified, on-demand allocation of entries (no extra memory consumption on lossless links); cache allocation is local to the module / exported as service; * provision of RFC-compliant algorithm to re-compute average loss interval; * provision of comprehensive, new loss detection algorithm - support for all cases of loss, including re-ordered/duplicate packets; - waiting for NDUPACK=3 packets to fill the hole; - updating loss records when a late-arriving packet fills a hole. Signed-off-by: Gerrit Renker Signed-off-by: Ian McDonald Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller