| #ifndef _TFRC_H_ |
| #define _TFRC_H_ |
| /* |
| * net/dccp/ccids/lib/tfrc.h |
| * |
| * Copyright (c) 2007 The University of Aberdeen, Scotland, UK |
| * Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand. |
| * Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz> |
| * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| */ |
| #include <linux/types.h> |
| #include <asm/div64.h> |
| #include "../../dccp.h" |
| /* internal includes that this module exports: */ |
| #include "loss_interval.h" |
| #include "packet_history.h" |
| |
| #ifdef CONFIG_IP_DCCP_TFRC_DEBUG |
| extern int tfrc_debug; |
| #define tfrc_pr_debug(format, a...) DCCP_PR_DEBUG(tfrc_debug, format, ##a) |
| #else |
| #define tfrc_pr_debug(format, a...) |
| #endif |
| |
| /* integer-arithmetic divisions of type (a * 1000000)/b */ |
| static inline u64 scaled_div(u64 a, u32 b) |
| { |
| BUG_ON(b==0); |
| a *= 1000000; |
| do_div(a, b); |
| return a; |
| } |
| |
| static inline u32 scaled_div32(u64 a, u32 b) |
| { |
| u64 result = scaled_div(a, b); |
| |
| if (result > UINT_MAX) { |
| DCCP_CRIT("Overflow: a(%llu)/b(%u) > ~0U", |
| (unsigned long long)a, b); |
| return UINT_MAX; |
| } |
| return result; |
| } |
| |
| /** |
| * tfrc_ewma - Exponentially weighted moving average |
| * @weight: Weight to be used as damping factor, in units of 1/10 |
| */ |
| static inline u32 tfrc_ewma(const u32 avg, const u32 newval, const u8 weight) |
| { |
| return avg ? (weight * avg + (10 - weight) * newval) / 10 : newval; |
| } |
| |
| extern u32 tfrc_calc_x(u16 s, u32 R, u32 p); |
| extern u32 tfrc_calc_x_reverse_lookup(u32 fvalue); |
| |
| #endif /* _TFRC_H_ */ |