From e6bccd357343e98db9e1fd0d487f4f924e1a7921 Mon Sep 17 00:00:00 2001 From: Ian McDonald Date: Sat, 26 Aug 2006 19:01:30 -0700 Subject: [DCCP]: Update contact details and copyright Just updating copyright and contacts Signed off by: Ian McDonald Signed-off-by: David S. Miller --- net/dccp/ccids/lib/loss_interval.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/dccp/ccids/lib/loss_interval.c') diff --git a/net/dccp/ccids/lib/loss_interval.c b/net/dccp/ccids/lib/loss_interval.c index 5d7b7d86438..b93d9fc98cb 100644 --- a/net/dccp/ccids/lib/loss_interval.c +++ b/net/dccp/ccids/lib/loss_interval.c @@ -2,7 +2,7 @@ * net/dccp/ccids/lib/loss_interval.c * * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. - * Copyright (c) 2005 Ian McDonald + * Copyright (c) 2005-6 Ian McDonald * Copyright (c) 2005 Arnaldo Carvalho de Melo * * This program is free software; you can redistribute it and/or modify -- cgit v1.2.3 From 66a377c5041e1e399633153c8b500d457281e7c1 Mon Sep 17 00:00:00 2001 From: Ian McDonald Date: Sat, 26 Aug 2006 23:40:50 -0700 Subject: [DCCP]: Fix CCID3 This fixes CCID3 to give much closer performance to RFC4342. CCID3 is meant to alter sending rate based on RTT and loss. The performance was verified against: http://wand.net.nz/~perry/max_download.php For example I tested with netem and had the following parameters: Delayed Acks 1, MSS 256 bytes, RTT 105 ms, packet loss 5%. This gives a theoretical speed of 71.9 Kbits/s. I measured across three runs with this patch set and got 70.1 Kbits/s. Without this patchset the average was 232 Kbits/s which means Linux can't be used for CCID3 research properly. I also tested with netem turned off so box just acting as router with 1.2 msec RTT. The performance with this is the same with or without the patch at around 30 Mbit/s. Signed off by: Ian McDonald Signed-off-by: David S. Miller --- net/dccp/ccids/lib/loss_interval.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) (limited to 'net/dccp/ccids/lib/loss_interval.c') diff --git a/net/dccp/ccids/lib/loss_interval.c b/net/dccp/ccids/lib/loss_interval.c index b93d9fc98cb..906c81ab9d4 100644 --- a/net/dccp/ccids/lib/loss_interval.c +++ b/net/dccp/ccids/lib/loss_interval.c @@ -12,6 +12,7 @@ */ #include +#include #include "loss_interval.h" @@ -90,13 +91,13 @@ u32 dccp_li_hist_calc_i_mean(struct list_head *list) u32 w_tot = 0; list_for_each_entry_safe(li_entry, li_next, list, dccplih_node) { - if (i < DCCP_LI_HIST_IVAL_F_LENGTH) { + if (li_entry->dccplih_interval != ~0) { i_tot0 += li_entry->dccplih_interval * dccp_li_hist_w[i]; w_tot += dccp_li_hist_w[i]; + if (i != 0) + i_tot1 += li_entry->dccplih_interval * dccp_li_hist_w[i - 1]; } - if (i != 0) - i_tot1 += li_entry->dccplih_interval * dccp_li_hist_w[i - 1]; if (++i > DCCP_LI_HIST_IVAL_F_LENGTH) break; @@ -107,37 +108,36 @@ u32 dccp_li_hist_calc_i_mean(struct list_head *list) i_tot = max(i_tot0, i_tot1); - /* FIXME: Why do we do this? -Ian McDonald */ - if (i_tot * 4 < w_tot) - i_tot = w_tot * 4; + if (!w_tot) { + LIMIT_NETDEBUG(KERN_WARNING "%s: w_tot = 0\n", __FUNCTION__); + return 1; + } - return i_tot * 4 / w_tot; + return i_tot / w_tot; } EXPORT_SYMBOL_GPL(dccp_li_hist_calc_i_mean); -struct dccp_li_hist_entry *dccp_li_hist_interval_new(struct dccp_li_hist *hist, - struct list_head *list, - const u64 seq_loss, - const u8 win_loss) +int dccp_li_hist_interval_new(struct dccp_li_hist *hist, + struct list_head *list, const u64 seq_loss, const u8 win_loss) { - struct dccp_li_hist_entry *tail = NULL, *entry; + struct dccp_li_hist_entry *entry; int i; - for (i = 0; i <= DCCP_LI_HIST_IVAL_F_LENGTH; ++i) { + for (i = 0; i < DCCP_LI_HIST_IVAL_F_LENGTH; i++) { entry = dccp_li_hist_entry_new(hist, SLAB_ATOMIC); if (entry == NULL) { dccp_li_hist_purge(hist, list); - return NULL; + dump_stack(); + return 0; } - if (tail == NULL) - tail = entry; + entry->dccplih_interval = ~0; list_add(&entry->dccplih_node, list); } entry->dccplih_seqno = seq_loss; entry->dccplih_win_count = win_loss; - return tail; + return 1; } EXPORT_SYMBOL_GPL(dccp_li_hist_interval_new); -- cgit v1.2.3