[TFRC]: Migrate TX history to singly-linked lis

This patch was based on another made by Gerrit Renker, his changelog was:

    ------------------------------------------------------
The patch set migrates TFRC TX history to a singly-linked list.

The details are:
 * use of a consistent naming scheme (all TFRC functions now begin with `tfrc_');
 * allocation and cleanup are taken care of internally;
 * provision of a lookup function, which is used by the CCID TX infrastructure
   to determine the time a packet was sent (in turn used for RTT sampling);
 * integration of the new interface with the present use in CCID3.
    ------------------------------------------------------

Simplifications I did:

. removing the tfrc_tx_hist_head that had a pointer to the list head and
  another for the slabcache.
. No need for creating a slabcache for each CCID that wants to use the TFRC
  tx history routines, create a single slabcache when the dccp_tfrc_lib module
  init routine is called.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arnaldo Carvalho de Melo
2007-11-28 11:15:40 -02:00
committed by David S. Miller
parent ea4f76ae13
commit 276f2edc52
5 changed files with 102 additions and 187 deletions

View File

@@ -1,10 +1,9 @@
/*
* net/dccp/packet_history.h
* Packet RX/TX history data structures and routines for TFRC-based protocols.
*
* Copyright (c) 2007 The University of Aberdeen, Scotland, UK
* Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
*
* An implementation of the DCCP protocol
*
* This code has been developed by the University of Waikato WAND
* research group. For further information please see http://www.wand.net.nz/
* or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz
@@ -49,71 +48,23 @@
#define TFRC_WIN_COUNT_PER_RTT 4
#define TFRC_WIN_COUNT_LIMIT 16
/*
* Transmitter History data structures and declarations
/**
* tfrc_tx_hist_entry - Simple singly-linked TX history list
* @next: next oldest entry (LIFO order)
* @seqno: sequence number of this entry
* @stamp: send time of packet with sequence number @seqno
*/
struct dccp_tx_hist_entry {
struct list_head dccphtx_node;
u64 dccphtx_seqno:48,
dccphtx_sent:1;
u32 dccphtx_rtt;
ktime_t dccphtx_tstamp;
struct tfrc_tx_hist_entry {
struct tfrc_tx_hist_entry *next;
u64 seqno;
ktime_t stamp;
};
struct dccp_tx_hist {
struct kmem_cache *dccptxh_slab;
};
extern int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno);
extern void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp);
extern struct dccp_tx_hist *dccp_tx_hist_new(const char *name);
extern void dccp_tx_hist_delete(struct dccp_tx_hist *hist);
static inline struct dccp_tx_hist_entry *
dccp_tx_hist_entry_new(struct dccp_tx_hist *hist,
const gfp_t prio)
{
struct dccp_tx_hist_entry *entry = kmem_cache_alloc(hist->dccptxh_slab,
prio);
if (entry != NULL)
entry->dccphtx_sent = 0;
return entry;
}
static inline struct dccp_tx_hist_entry *
dccp_tx_hist_head(struct list_head *list)
{
struct dccp_tx_hist_entry *head = NULL;
if (!list_empty(list))
head = list_entry(list->next, struct dccp_tx_hist_entry,
dccphtx_node);
return head;
}
extern struct dccp_tx_hist_entry *
dccp_tx_hist_find_entry(const struct list_head *list,
const u64 seq);
static inline void dccp_tx_hist_add_entry(struct list_head *list,
struct dccp_tx_hist_entry *entry)
{
list_add(&entry->dccphtx_node, list);
}
static inline void dccp_tx_hist_entry_delete(struct dccp_tx_hist *hist,
struct dccp_tx_hist_entry *entry)
{
if (entry != NULL)
kmem_cache_free(hist->dccptxh_slab, entry);
}
extern void dccp_tx_hist_purge(struct dccp_tx_hist *hist,
struct list_head *list);
extern void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
struct list_head *list,
struct dccp_tx_hist_entry *next);
extern struct tfrc_tx_hist_entry *
tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 ackno);
/*
* Receiver History data structures and declarations