1 /* SPDX-License-Identifier: LGPL-2.1-or-later
2 * Copyright © 2019 VMware, Inc. */
3
4 #include "alloc-util.h"
5 #include "extract-word.h"
6 #include "fileio.h"
7 #include "parse-util.h"
8 #include "percent-util.h"
9 #include "tc-util.h"
10 #include "time-util.h"
11
tc_init(double * ret_ticks_in_usec,uint32_t * ret_hz)12 int tc_init(double *ret_ticks_in_usec, uint32_t *ret_hz) {
13 static double ticks_in_usec = -1;
14 static uint32_t hz;
15
16 if (ticks_in_usec < 0) {
17 uint32_t clock_resolution, ticks_to_usec, usec_to_ticks;
18 _cleanup_free_ char *line = NULL;
19 double clock_factor;
20 int r;
21
22 r = read_one_line_file("/proc/net/psched", &line);
23 if (r < 0)
24 return r;
25
26 r = sscanf(line, "%08x%08x%08x%08x", &ticks_to_usec, &usec_to_ticks, &clock_resolution, &hz);
27 if (r < 4)
28 return -EIO;
29
30 clock_factor = (double) clock_resolution / USEC_PER_SEC;
31 ticks_in_usec = (double) ticks_to_usec / usec_to_ticks * clock_factor;
32 }
33
34 if (ret_ticks_in_usec)
35 *ret_ticks_in_usec = ticks_in_usec;
36 if (ret_hz)
37 *ret_hz = hz;
38
39 return 0;
40 }
41
tc_time_to_tick(usec_t t,uint32_t * ret)42 int tc_time_to_tick(usec_t t, uint32_t *ret) {
43 double ticks_in_usec;
44 usec_t a;
45 int r;
46
47 assert(ret);
48
49 r = tc_init(&ticks_in_usec, NULL);
50 if (r < 0)
51 return r;
52
53 a = t * ticks_in_usec;
54 if (a > UINT32_MAX)
55 return -ERANGE;
56
57 *ret = a;
58 return 0;
59 }
60
parse_tc_percent(const char * s,uint32_t * ret_fraction)61 int parse_tc_percent(const char *s, uint32_t *ret_fraction) {
62 int r;
63
64 assert(s);
65 assert(ret_fraction);
66
67 r = parse_permyriad(s);
68 if (r < 0)
69 return r;
70
71 *ret_fraction = (double) r / 10000 * UINT32_MAX;
72 return 0;
73 }
74
tc_transmit_time(uint64_t rate,uint32_t size,uint32_t * ret)75 int tc_transmit_time(uint64_t rate, uint32_t size, uint32_t *ret) {
76 return tc_time_to_tick(USEC_PER_SEC * ((double)size / (double)rate), ret);
77 }
78
tc_fill_ratespec_and_table(struct tc_ratespec * rate,uint32_t * rtab,uint32_t mtu)79 int tc_fill_ratespec_and_table(struct tc_ratespec *rate, uint32_t *rtab, uint32_t mtu) {
80 uint32_t cell_log = 0;
81 int r;
82
83 if (mtu == 0)
84 mtu = 2047;
85
86 while ((mtu >> cell_log) > 255)
87 cell_log++;
88
89 for (size_t i = 0; i < 256; i++) {
90 uint32_t sz;
91
92 sz = (i + 1) << cell_log;
93 if (sz < rate->mpu)
94 sz = rate->mpu;
95 r = tc_transmit_time(rate->rate, sz, &rtab[i]);
96 if (r < 0)
97 return r;
98 }
99
100 rate->cell_align = -1;
101 rate->cell_log = cell_log;
102 rate->linklayer = TC_LINKLAYER_ETHERNET;
103 return 0;
104 }
105
parse_handle(const char * t,uint32_t * ret)106 int parse_handle(const char *t, uint32_t *ret) {
107 _cleanup_free_ char *word = NULL;
108 uint16_t major, minor;
109 int r;
110
111 assert(t);
112 assert(ret);
113
114 /* Extract the major number. */
115 r = extract_first_word(&t, &word, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
116 if (r < 0)
117 return r;
118 if (r == 0)
119 return -EINVAL;
120 if (!t)
121 return -EINVAL;
122
123 r = safe_atou16_full(word, 16, &major);
124 if (r < 0)
125 return r;
126
127 r = safe_atou16_full(t, 16, &minor);
128 if (r < 0)
129 return r;
130
131 *ret = ((uint32_t) major << 16) | minor;
132 return 0;
133 }
134