summaryrefslogtreecommitdiff
path: root/src/basic/cpu-set-util.c
blob: 5024290557a07580775a1f8cefd82ba0047beabd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
/* SPDX-License-Identifier: LGPL-2.1+ */
/***
  Copyright © 2015 Filipe Brandenburger
***/

#include <errno.h>
#include <stddef.h>
#include <stdio.h>
#include <syslog.h>

#include "alloc-util.h"
#include "cpu-set-util.h"
#include "extract-word.h"
#include "log.h"
#include "macro.h"
#include "parse-util.h"
#include "string-util.h"
#include "util.h"

char* cpu_set_to_string(const CPUSet *a) {
        _cleanup_free_ char *str = NULL;
        size_t allocated = 0, len = 0;
        int i, r;

        for (i = 0; (size_t) i < a->allocated * 8; i++) {
                if (!CPU_ISSET_S(i, a->allocated, a->set))
                        continue;

                if (!GREEDY_REALLOC(str, allocated, len + 1 + DECIMAL_STR_MAX(int)))
                        return NULL;

                r = sprintf(str + len, len > 0 ? " %d" : "%d", i);
                assert_se(r > 0);
                len += r;
        }

        return TAKE_PTR(str) ?: strdup("");
}

char *cpu_set_to_range_string(const CPUSet *set) {
        unsigned range_start = 0, range_end;
        _cleanup_free_ char *str = NULL;
        size_t allocated = 0, len = 0;
        bool in_range = false;
        int r;

        for (unsigned i = 0; i < set->allocated * 8; i++)
                if (CPU_ISSET_S(i, set->allocated, set->set)) {
                        if (in_range)
                                range_end++;
                        else {
                                range_start = range_end = i;
                                in_range = true;
                        }
                } else if (in_range) {
                        in_range = false;

                        if (!GREEDY_REALLOC(str, allocated, len + 2 + 2 * DECIMAL_STR_MAX(unsigned)))
                                return NULL;

                        if (range_end > range_start || len == 0)
                                r = sprintf(str + len, len > 0 ? " %d-%d" : "%d-%d", range_start, range_end);
                        else
                                r = sprintf(str + len, len > 0 ? " %d" : "%d", range_start);
                        assert_se(r > 0);
                        len += r;
                }

        if (in_range) {
                if (!GREEDY_REALLOC(str, allocated, len + 2 + 2 * DECIMAL_STR_MAX(int)))
                        return NULL;

                if (range_end > range_start || len == 0)
                        r = sprintf(str + len, len > 0 ? " %d-%d" : "%d-%d", range_start, range_end);
                else
                        r = sprintf(str + len, len > 0 ? " %d" : "%d", range_start);
                assert_se(r > 0);
        }

        return TAKE_PTR(str) ?: strdup("");
}

int cpu_set_realloc(CPUSet *cpu_set, unsigned ncpus) {
        size_t need;

        assert(cpu_set);

        need = CPU_ALLOC_SIZE(ncpus);
        if (need > cpu_set->allocated) {
                cpu_set_t *t;

                t = realloc(cpu_set->set, need);
                if (!t)
                        return -ENOMEM;

                memzero((uint8_t*) t + cpu_set->allocated, need - cpu_set->allocated);

                cpu_set->set = t;
                cpu_set->allocated = need;
        }

        return 0;
}

static int cpu_set_add(CPUSet *cpu_set, unsigned cpu) {
        int r;

        if (cpu >= 8192)
                /* As of kernel 5.1, CONFIG_NR_CPUS can be set to 8192 on PowerPC */
                return -ERANGE;

        r = cpu_set_realloc(cpu_set, cpu + 1);
        if (r < 0)
                return r;

        CPU_SET_S(cpu, cpu_set->allocated, cpu_set->set);
        return 0;
}

int cpu_set_add_all(CPUSet *a, const CPUSet *b) {
        int r;

        /* Do this backwards, so if we fail, we fail before changing anything. */
        for (unsigned cpu_p1 = b->allocated * 8; cpu_p1 > 0; cpu_p1--)
                if (CPU_ISSET_S(cpu_p1 - 1, b->allocated, b->set)) {
                        r = cpu_set_add(a, cpu_p1 - 1);
                        if (r < 0)
                                return r;
                }

        return 0;
}

int parse_cpu_set_full(
                const char *rvalue,
                CPUSet *cpu_set,
                bool warn,
                const char *unit,
                const char *filename,
                unsigned line,
                const char *lvalue) {

        _cleanup_(cpu_set_reset) CPUSet c = {};
        const char *p = rvalue;

        assert(p);

        for (;;) {
                _cleanup_free_ char *word = NULL;
                unsigned cpu_lower, cpu_upper;
                int r;

                r = extract_first_word(&p, &word, WHITESPACE ",", EXTRACT_QUOTES);
                if (r == -ENOMEM)
                        return warn ? log_oom() : -ENOMEM;
                if (r < 0)
                        return warn ? log_syntax(unit, LOG_ERR, filename, line, r, "Invalid value for %s: %s", lvalue, rvalue) : r;
                if (r == 0)
                        break;

                r = parse_range(word, &cpu_lower, &cpu_upper);
                if (r < 0)
                        return warn ? log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse CPU affinity '%s'", word) : r;

                if (cpu_lower > cpu_upper) {
                        if (warn)
                                log_syntax(unit, LOG_WARNING, filename, line, 0, "Range '%s' is invalid, %u > %u, ignoring.",
                                           word, cpu_lower, cpu_upper);

                        /* Make sure something is allocated, to distinguish this from the empty case */
                        r = cpu_set_realloc(&c, 1);
                        if (r < 0)
                                return r;
                }

                for (unsigned cpu_p1 = MIN(cpu_upper, UINT_MAX-1) + 1; cpu_p1 > cpu_lower; cpu_p1--) {
                        r = cpu_set_add(&c, cpu_p1 - 1);
                        if (r < 0)
                                return warn ? log_syntax(unit, LOG_ERR, filename, line, r,
                                                         "Cannot add CPU %u to set: %m", cpu_p1 - 1) : r;
                }
        }

        /* On success, transfer ownership to the output variable */
        *cpu_set = c;
        c = (CPUSet) {};

        return 0;
}

int parse_cpu_set_extend(
                const char *rvalue,
                CPUSet *old,
                bool warn,
                const char *unit,
                const char *filename,
                unsigned line,
                const char *lvalue) {

        _cleanup_(cpu_set_reset) CPUSet cpuset = {};
        int r;

        r = parse_cpu_set_full(rvalue, &cpuset, true, unit, filename, line, lvalue);
        if (r < 0)
                return r;

        if (!cpuset.set) {
                /* An empty assignment resets the CPU list */
                cpu_set_reset(old);
                return 0;
        }

        if (!old->set) {
                *old = cpuset;
                cpuset = (CPUSet) {};
                return 0;
        }

        return cpu_set_add_all(old, &cpuset);
}

int cpus_in_affinity_mask(void) {
        size_t n = 16;
        int r;

        for (;;) {
                cpu_set_t *c;

                c = CPU_ALLOC(n);
                if (!c)
                        return -ENOMEM;

                if (sched_getaffinity(0, CPU_ALLOC_SIZE(n), c) >= 0) {
                        int k;

                        k = CPU_COUNT_S(CPU_ALLOC_SIZE(n), c);
                        CPU_FREE(c);

                        if (k <= 0)
                                return -EINVAL;

                        return k;
                }

                r = -errno;
                CPU_FREE(c);

                if (r != -EINVAL)
                        return r;
                if (n > SIZE_MAX/2)
                        return -ENOMEM;
                n *= 2;
        }
}

int cpu_set_to_dbus(const CPUSet *set, uint8_t **ret, size_t *allocated) {
        uint8_t *out;

        assert(set);
        assert(ret);

        out = new0(uint8_t, set->allocated);
        if (!out)
                return -ENOMEM;

        for (unsigned cpu = 0; cpu < set->allocated * 8; cpu++)
                if (CPU_ISSET_S(cpu, set->allocated, set->set))
                        out[cpu / 8] |= 1u << (cpu % 8);

        *ret = out;
        *allocated = set->allocated;
        return 0;
}

int cpu_set_from_dbus(const uint8_t *bits, size_t size, CPUSet *set) {
        _cleanup_(cpu_set_reset) CPUSet s = {};
        int r;

        assert(bits);
        assert(set);

        for (unsigned cpu = size * 8; cpu > 0; cpu--)
                if (bits[(cpu - 1) / 8] & (1u << ((cpu - 1) % 8))) {
                        r = cpu_set_add(&s, cpu - 1);
                        if (r < 0)
                                return r;
                }

        *set = s;
        s = (CPUSet) {};
        return 0;
}