linux/net/dccp/ccids/lib/tfrc.h
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

74 lines
2.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _TFRC_H_
#define _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
*/
#include <linux/types.h>
#include <linux/math64.h>
#include "../../dccp.h"
/* internal includes that this library exports: */
#include "loss_interval.h"
#include "packet_history.h"
#ifdef CONFIG_IP_DCCP_TFRC_DEBUG
extern bool 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, u64 b)
{
BUG_ON(b == 0);
return div64_u64(a * 1000000, b);
}
static inline u32 scaled_div32(u64 a, u64 b)
{
u64 result = scaled_div(a, b);
if (result > UINT_MAX) {
DCCP_CRIT("Overflow: %llu/%llu > UINT_MAX",
(unsigned long long)a, (unsigned long long)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;
}
u32 tfrc_calc_x(u16 s, u32 R, u32 p);
u32 tfrc_calc_x_reverse_lookup(u32 fvalue);
u32 tfrc_invert_loss_event_rate(u32 loss_event_rate);
int tfrc_tx_packet_history_init(void);
void tfrc_tx_packet_history_exit(void);
int tfrc_rx_packet_history_init(void);
void tfrc_rx_packet_history_exit(void);
int tfrc_li_init(void);
void tfrc_li_exit(void);
#ifdef CONFIG_IP_DCCP_TFRC_LIB
int tfrc_lib_init(void);
void tfrc_lib_exit(void);
#else
#define tfrc_lib_init() (0)
#define tfrc_lib_exit()
#endif
#endif /* _TFRC_H_ */