ae6706f067
And put this into net/dccp/ccids/lib/, where packet_history.[ch] will also be moved and then we'll have a tfrc_lib.ko module that will be used by dccp_ccid3.ko and other CCIDs that are variations of TFRC (RFC 3448). Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
145 lines
3.5 KiB
C
145 lines
3.5 KiB
C
/*
|
|
* net/dccp/ccids/lib/loss_interval.c
|
|
*
|
|
* Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
|
|
* Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
|
|
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/config.h>
|
|
#include <linux/module.h>
|
|
|
|
#include "loss_interval.h"
|
|
|
|
struct dccp_li_hist *dccp_li_hist_new(const char *name)
|
|
{
|
|
struct dccp_li_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
|
|
static const char dccp_li_hist_mask[] = "li_hist_%s";
|
|
char *slab_name;
|
|
|
|
if (hist == NULL)
|
|
goto out;
|
|
|
|
slab_name = kmalloc(strlen(name) + sizeof(dccp_li_hist_mask) - 1,
|
|
GFP_ATOMIC);
|
|
if (slab_name == NULL)
|
|
goto out_free_hist;
|
|
|
|
sprintf(slab_name, dccp_li_hist_mask, name);
|
|
hist->dccplih_slab = kmem_cache_create(slab_name,
|
|
sizeof(struct dccp_li_hist_entry),
|
|
0, SLAB_HWCACHE_ALIGN,
|
|
NULL, NULL);
|
|
if (hist->dccplih_slab == NULL)
|
|
goto out_free_slab_name;
|
|
out:
|
|
return hist;
|
|
out_free_slab_name:
|
|
kfree(slab_name);
|
|
out_free_hist:
|
|
kfree(hist);
|
|
hist = NULL;
|
|
goto out;
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(dccp_li_hist_new);
|
|
|
|
void dccp_li_hist_delete(struct dccp_li_hist *hist)
|
|
{
|
|
const char* name = kmem_cache_name(hist->dccplih_slab);
|
|
|
|
kmem_cache_destroy(hist->dccplih_slab);
|
|
kfree(name);
|
|
kfree(hist);
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(dccp_li_hist_delete);
|
|
|
|
void dccp_li_hist_purge(struct dccp_li_hist *hist, struct list_head *list)
|
|
{
|
|
struct dccp_li_hist_entry *entry, *next;
|
|
|
|
list_for_each_entry_safe(entry, next, list, dccplih_node) {
|
|
list_del_init(&entry->dccplih_node);
|
|
kmem_cache_free(hist->dccplih_slab, entry);
|
|
}
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(dccp_li_hist_purge);
|
|
|
|
/* Weights used to calculate loss event rate */
|
|
/*
|
|
* These are integers as per section 8 of RFC3448. We can then divide by 4 *
|
|
* when we use it.
|
|
*/
|
|
static const int dccp_li_hist_w[DCCP_LI_HIST_IVAL_F_LENGTH] = {
|
|
4, 4, 4, 4, 3, 2, 1, 1,
|
|
};
|
|
|
|
u32 dccp_li_hist_calc_i_mean(struct list_head *list)
|
|
{
|
|
struct dccp_li_hist_entry *li_entry, *li_next;
|
|
int i = 0;
|
|
u32 i_tot;
|
|
u32 i_tot0 = 0;
|
|
u32 i_tot1 = 0;
|
|
u32 w_tot = 0;
|
|
|
|
list_for_each_entry_safe(li_entry, li_next, list, dccplih_node) {
|
|
if (i < DCCP_LI_HIST_IVAL_F_LENGTH) {
|
|
i_tot0 += li_entry->dccplih_interval * dccp_li_hist_w[i];
|
|
w_tot += dccp_li_hist_w[i];
|
|
}
|
|
|
|
if (i != 0)
|
|
i_tot1 += li_entry->dccplih_interval * dccp_li_hist_w[i - 1];
|
|
|
|
if (++i > DCCP_LI_HIST_IVAL_F_LENGTH)
|
|
break;
|
|
}
|
|
|
|
if (i != DCCP_LI_HIST_IVAL_F_LENGTH)
|
|
return 0;
|
|
|
|
i_tot = max(i_tot0, i_tot1);
|
|
|
|
/* FIXME: Why do we do this? -Ian McDonald */
|
|
if (i_tot * 4 < w_tot)
|
|
i_tot = w_tot * 4;
|
|
|
|
return i_tot * 4 / w_tot;
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(dccp_li_hist_calc_i_mean);
|
|
|
|
struct dccp_li_hist_entry *dccp_li_hist_interval_new(struct dccp_li_hist *hist,
|
|
struct list_head *list,
|
|
const u64 seq_loss,
|
|
const u8 win_loss)
|
|
{
|
|
struct dccp_li_hist_entry *tail = NULL, *entry;
|
|
int i;
|
|
|
|
for (i = 0; i <= DCCP_LI_HIST_IVAL_F_LENGTH; ++i) {
|
|
entry = dccp_li_hist_entry_new(hist, SLAB_ATOMIC);
|
|
if (entry == NULL) {
|
|
dccp_li_hist_purge(hist, list);
|
|
return NULL;
|
|
}
|
|
if (tail == NULL)
|
|
tail = entry;
|
|
list_add(&entry->dccplih_node, list);
|
|
}
|
|
|
|
entry->dccplih_seqno = seq_loss;
|
|
entry->dccplih_win_count = win_loss;
|
|
return tail;
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(dccp_li_hist_interval_new);
|