diff options
Diffstat (limited to 'net/dccp/ccids/lib/packet_history.h')
| -rw-r--r-- | net/dccp/ccids/lib/packet_history.h | 83 |
1 files changed, 37 insertions, 46 deletions
diff --git a/net/dccp/ccids/lib/packet_history.h b/net/dccp/ccids/lib/packet_history.h index 5b0b9834340..3dfd182b0e6 100644 --- a/net/dccp/ccids/lib/packet_history.h +++ b/net/dccp/ccids/lib/packet_history.h @@ -37,15 +37,9 @@ #define _DCCP_PKT_HIST_ #include <linux/ktime.h> -#include <linux/list.h> -#include <linux/slab.h> -#include "tfrc.h" +#include <linux/types.h> -/* Number of later packets received before one is considered lost */ -#define TFRC_RECV_NUM_LATE_LOSS 3 - -#define TFRC_WIN_COUNT_PER_RTT 4 -#define TFRC_WIN_COUNT_LIMIT 16 +struct sk_buff; struct tfrc_tx_hist_entry; @@ -54,11 +48,20 @@ extern void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp); extern u32 tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head, const u64 seqno, const ktime_t now); -/* - * Receiver History data structures and declarations +/* Subtraction a-b modulo-16, respects circular wrap-around */ +#define SUB16(a, b) (((a) + 16 - (b)) & 0xF) + +/* Number of packets to wait after a missing packet (RFC 4342, 6.1) */ +#define TFRC_NDUPACK 3 + +/** + * tfrc_rx_hist_entry - Store information about a single received packet + * @tfrchrx_seqno: DCCP packet sequence number + * @tfrchrx_ccval: window counter value of packet (RFC 4342, 8.1) + * @tfrchrx_ndp: the NDP count (if any) of the packet + * @tfrchrx_tstamp: actual receive time of packet */ struct tfrc_rx_hist_entry { - struct list_head tfrchrx_node; u64 tfrchrx_seqno:48, tfrchrx_ccval:4, tfrchrx_type:4; @@ -66,42 +69,30 @@ struct tfrc_rx_hist_entry { ktime_t tfrchrx_tstamp; }; -extern struct tfrc_rx_hist_entry * - tfrc_rx_hist_entry_new(const u32 ndp, - const struct sk_buff *skb, - const gfp_t prio); - -static inline struct tfrc_rx_hist_entry * - tfrc_rx_hist_head(struct list_head *list) -{ - struct tfrc_rx_hist_entry *head = NULL; - - if (!list_empty(list)) - head = list_entry(list->next, struct tfrc_rx_hist_entry, - tfrchrx_node); - return head; -} - -extern int tfrc_rx_hist_find_entry(const struct list_head *list, const u64 seq, - u8 *ccval); -extern struct tfrc_rx_hist_entry * - tfrc_rx_hist_find_data_packet(const struct list_head *list); - -extern void tfrc_rx_hist_add_packet(struct list_head *rx_list, - struct list_head *li_list, - struct tfrc_rx_hist_entry *packet, - u64 nonloss_seqno); - -extern void tfrc_rx_hist_purge(struct list_head *list); +/** + * tfrc_rx_hist - RX history structure for TFRC-based protocols + * + * @ring: Packet history for RTT sampling and loss detection + * @loss_count: Number of entries in circular history + * @loss_start: Movable index (for loss detection) + * @rtt_sample_prev: Used during RTT sampling, points to candidate entry + */ +struct tfrc_rx_hist { + struct tfrc_rx_hist_entry *ring[TFRC_NDUPACK + 1]; + u8 loss_count:2, + loss_start:2; +#define rtt_sample_prev loss_start +}; -static inline int - tfrc_rx_hist_entry_data_packet(const struct tfrc_rx_hist_entry *entry) -{ - return entry->tfrchrx_type == DCCP_PKT_DATA || - entry->tfrchrx_type == DCCP_PKT_DATAACK; -} +extern void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h, + const struct sk_buff *skb, const u32 ndp); -extern u64 tfrc_rx_hist_detect_loss(struct list_head *rx_list, - struct list_head *li_list, u8 *win_loss); +extern int tfrc_rx_hist_duplicate(struct tfrc_rx_hist *h, struct sk_buff *skb); +extern int tfrc_rx_hist_new_loss_indicated(struct tfrc_rx_hist *h, + const struct sk_buff *skb, u32 ndp); +extern u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h, + const struct sk_buff *skb); +extern int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h); +extern void tfrc_rx_hist_purge(struct tfrc_rx_hist *h); #endif /* _DCCP_PKT_HIST_ */ |