mirror of https://github.com/schoebel/mars
104 lines
2.4 KiB
C
104 lines
2.4 KiB
C
/*
|
|
* MARS Long Distance Replication Software
|
|
*
|
|
* This file is part of MARS project: http://schoebel.github.io/mars/
|
|
*
|
|
* Copyright (C) 2010-2014 Thomas Schoebel-Theuer
|
|
* Copyright (C) 2011-2014 1&1 Internet AG
|
|
*
|
|
* 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.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
|
|
// (c) 2012 Thomas Schoebel-Theuer
|
|
|
|
//#define BRICK_DEBUGGING
|
|
//#define MARS_DEBUGGING
|
|
//#define IO_DEBUGGING
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
|
|
#include "mars.h"
|
|
#include "lib_rank.h"
|
|
|
|
void ranking_compute(struct rank_data *rkd, const struct rank_info rki[], int x)
|
|
{
|
|
int points = 0;
|
|
int i;
|
|
|
|
for (i = 0; ; i++) {
|
|
int x0;
|
|
int x1;
|
|
int y0;
|
|
int y1;
|
|
|
|
x0 = rki[i].rki_x;
|
|
if (x < x0)
|
|
break;
|
|
|
|
x1 = rki[i+1].rki_x;
|
|
|
|
if (unlikely(x1 == RKI_DUMMY)) {
|
|
points = rki[i].rki_y;
|
|
break;
|
|
}
|
|
|
|
if (x > x1)
|
|
continue;
|
|
|
|
y0 = rki[i].rki_y;
|
|
y1 = rki[i+1].rki_y;
|
|
|
|
// linear interpolation
|
|
points = ((long long)(x - x0) * (long long)(y1 - y0)) / (x1 - x0) + y0;
|
|
MARS_IO("i = %d x0 = %d x1 = %d y0 = %d y1 = %d points = %d\n", i, x0, x1, y0, y1, points);
|
|
break;
|
|
}
|
|
rkd->rkd_tmp += points;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ranking_compute);
|
|
|
|
int ranking_select(struct rank_data rkd[], int rkd_count)
|
|
{
|
|
int res = -1;
|
|
long long max = LLONG_MIN / 2;
|
|
int i;
|
|
|
|
MARS_IO("rkd_count = %d\n", rkd_count);
|
|
|
|
for (i = 0; i < rkd_count; i++) {
|
|
struct rank_data *tmp = &rkd[i];
|
|
long long rest = tmp->rkd_current_points;
|
|
if (rest <= 0)
|
|
continue;
|
|
//rest -= tmp->rkd_got;
|
|
if (rest > max) {
|
|
max = rest;
|
|
res = i;
|
|
}
|
|
}
|
|
/* Prevent underflow in the long term
|
|
* and reset the "clocks" after each round of
|
|
* weighted round-robin selection.
|
|
*/
|
|
if (max < 0 && res >= 0) {
|
|
for (i = 0; i < rkd_count; i++)
|
|
rkd[i].rkd_got += max;
|
|
}
|
|
MARS_IO("res = %d\n", res);
|
|
return res;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ranking_select);
|