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Diffstat (limited to 'net/dccp/ccids/lib/tfrc.h')
| -rw-r--r-- | net/dccp/ccids/lib/tfrc.h | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/net/dccp/ccids/lib/tfrc.h b/net/dccp/ccids/lib/tfrc.h new file mode 100644 index 000000000..0a63e8750 --- /dev/null +++ b/net/dccp/ccids/lib/tfrc.h @@ -0,0 +1,73 @@ +/* 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_ */ |