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13#include <stdio.h>
14#include <stdlib.h>
15#include <unistd.h>
16#include <fcntl.h>
17#include <math.h>
18#include <sys/socket.h>
19#include <netinet/in.h>
20#include <arpa/inet.h>
21#include <string.h>
22
23#include "utils.h"
24#include "tc_core.h"
25#include "tc_util.h"
26#include "tc_red.h"
27
28
29
30
31int tc_red_eval_P(unsigned int qmin, unsigned int qmax, double prob)
32{
33 int i = qmax - qmin;
34
35 if (!i)
36 return 0;
37 if (i < 0)
38 return -1;
39
40 prob /= i;
41
42 for (i = 0; i < 32; i++) {
43 if (prob > 1.0)
44 break;
45 prob *= 2;
46 }
47 if (i >= 32)
48 return -1;
49 return i;
50}
51
52
53
54
55
56int tc_red_eval_ewma(unsigned int qmin, unsigned int burst, unsigned int avpkt)
57{
58 int wlog = 1;
59 double W = 0.5;
60 double a = (double)burst + 1 - (double)qmin/avpkt;
61
62 if (a < 1.0) {
63 fprintf(stderr, "tc_red_eval_ewma() burst %u is too small ? Try burst %u\n",
64 burst, 1 + qmin/avpkt);
65 return -1;
66 }
67 for (wlog = 1; wlog < 32; wlog++, W /= 2) {
68 if (a <= (1 - pow(1-W, burst))/W)
69 return wlog;
70 }
71 return -1;
72}
73
74
75
76
77
78int tc_red_eval_idle_damping(int Wlog, unsigned int avpkt, unsigned int bps, __u8 *sbuf)
79{
80 double xmit_time = tc_calc_xmittime(bps, avpkt);
81 double lW = -log(1.0 - 1.0/(1<<Wlog))/xmit_time;
82 double maxtime = 31/lW;
83 int clog;
84 int i;
85
86 for (clog = 0; clog < 32; clog++) {
87 if (maxtime/(1<<clog) < 512)
88 break;
89 }
90 if (clog >= 32)
91 return -1;
92
93 sbuf[0] = 0;
94 for (i = 1; i < 255; i++) {
95 sbuf[i] = (i<<clog)*lW;
96 if (sbuf[i] > 31)
97 sbuf[i] = 31;
98 }
99 sbuf[255] = 31;
100 return clog;
101}
102
103void tc_red_print_flags(__u32 flags)
104{
105 if (flags & TC_RED_ECN)
106 print_bool(PRINT_ANY, "ecn", "ecn ", true);
107 else
108 print_bool(PRINT_ANY, "ecn", NULL, false);
109
110 if (flags & TC_RED_HARDDROP)
111 print_bool(PRINT_ANY, "harddrop", "harddrop ", true);
112 else
113 print_bool(PRINT_ANY, "harddrop", NULL, false);
114
115 if (flags & TC_RED_ADAPTATIVE)
116 print_bool(PRINT_ANY, "adaptive", "adaptive ", true);
117 else
118 print_bool(PRINT_ANY, "adaptive", NULL, false);
119
120 if (flags & TC_RED_NODROP)
121 print_bool(PRINT_ANY, "nodrop", "nodrop ", true);
122 else
123 print_bool(PRINT_ANY, "nodrop", NULL, false);
124}
125