1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 #ifndef _DCCP_LI_HIST_ 3 #define _DCCP_LI_HIST_ 4 /* 5 * Copyright (c) 2007 The University of Aberdeen, Scotland, UK 6 * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. 7 * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz> 8 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> 9 */ 10 #include <linux/ktime.h> 11 #include <linux/list.h> 12 #include <linux/slab.h> 13 14 /* 15 * Number of loss intervals (RFC 4342, 8.6.1). The history size is one more than 16 * NINTERVAL, since the `open' interval I_0 is always stored as the first entry. 17 */ 18 #define NINTERVAL 8 19 #define LIH_SIZE (NINTERVAL + 1) 20 21 /** 22 * tfrc_loss_interval - Loss history record for TFRC-based protocols 23 * @li_seqno: Highest received seqno before the start of loss 24 * @li_ccval: The CCVal belonging to @li_seqno 25 * @li_is_closed: Whether @li_seqno is older than 1 RTT 26 * @li_length: Loss interval sequence length 27 */ 28 struct tfrc_loss_interval { 29 u64 li_seqno:48, 30 li_ccval:4, 31 li_is_closed:1; 32 u32 li_length; 33 }; 34 35 /** 36 * tfrc_loss_hist - Loss record database 37 * @ring: Circular queue managed in LIFO manner 38 * @counter: Current count of entries (can be more than %LIH_SIZE) 39 * @i_mean: Current Average Loss Interval [RFC 3448, 5.4] 40 */ 41 struct tfrc_loss_hist { 42 struct tfrc_loss_interval *ring[LIH_SIZE]; 43 u8 counter; 44 u32 i_mean; 45 }; 46 47 static inline void tfrc_lh_init(struct tfrc_loss_hist *lh) 48 { 49 memset(lh, 0, sizeof(struct tfrc_loss_hist)); 50 } 51 52 static inline u8 tfrc_lh_is_initialised(struct tfrc_loss_hist *lh) 53 { 54 return lh->counter > 0; 55 } 56 57 static inline u8 tfrc_lh_length(struct tfrc_loss_hist *lh) 58 { 59 return min(lh->counter, (u8)LIH_SIZE); 60 } 61 62 struct tfrc_rx_hist; 63 64 int tfrc_lh_interval_add(struct tfrc_loss_hist *, struct tfrc_rx_hist *, 65 u32 (*first_li)(struct sock *), struct sock *); 66 u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *); 67 void tfrc_lh_cleanup(struct tfrc_loss_hist *lh); 68 69 #endif /* _DCCP_LI_HIST_ */ 70