xref: /openbmc/linux/tools/perf/util/cpumap.c (revision 12eb4683)
1 #include "util.h"
2 #include "fs.h"
3 #include "../perf.h"
4 #include "cpumap.h"
5 #include <assert.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 
9 static struct cpu_map *cpu_map__default_new(void)
10 {
11 	struct cpu_map *cpus;
12 	int nr_cpus;
13 
14 	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
15 	if (nr_cpus < 0)
16 		return NULL;
17 
18 	cpus = malloc(sizeof(*cpus) + nr_cpus * sizeof(int));
19 	if (cpus != NULL) {
20 		int i;
21 		for (i = 0; i < nr_cpus; ++i)
22 			cpus->map[i] = i;
23 
24 		cpus->nr = nr_cpus;
25 	}
26 
27 	return cpus;
28 }
29 
30 static struct cpu_map *cpu_map__trim_new(int nr_cpus, int *tmp_cpus)
31 {
32 	size_t payload_size = nr_cpus * sizeof(int);
33 	struct cpu_map *cpus = malloc(sizeof(*cpus) + payload_size);
34 
35 	if (cpus != NULL) {
36 		cpus->nr = nr_cpus;
37 		memcpy(cpus->map, tmp_cpus, payload_size);
38 	}
39 
40 	return cpus;
41 }
42 
43 struct cpu_map *cpu_map__read(FILE *file)
44 {
45 	struct cpu_map *cpus = NULL;
46 	int nr_cpus = 0;
47 	int *tmp_cpus = NULL, *tmp;
48 	int max_entries = 0;
49 	int n, cpu, prev;
50 	char sep;
51 
52 	sep = 0;
53 	prev = -1;
54 	for (;;) {
55 		n = fscanf(file, "%u%c", &cpu, &sep);
56 		if (n <= 0)
57 			break;
58 		if (prev >= 0) {
59 			int new_max = nr_cpus + cpu - prev - 1;
60 
61 			if (new_max >= max_entries) {
62 				max_entries = new_max + MAX_NR_CPUS / 2;
63 				tmp = realloc(tmp_cpus, max_entries * sizeof(int));
64 				if (tmp == NULL)
65 					goto out_free_tmp;
66 				tmp_cpus = tmp;
67 			}
68 
69 			while (++prev < cpu)
70 				tmp_cpus[nr_cpus++] = prev;
71 		}
72 		if (nr_cpus == max_entries) {
73 			max_entries += MAX_NR_CPUS;
74 			tmp = realloc(tmp_cpus, max_entries * sizeof(int));
75 			if (tmp == NULL)
76 				goto out_free_tmp;
77 			tmp_cpus = tmp;
78 		}
79 
80 		tmp_cpus[nr_cpus++] = cpu;
81 		if (n == 2 && sep == '-')
82 			prev = cpu;
83 		else
84 			prev = -1;
85 		if (n == 1 || sep == '\n')
86 			break;
87 	}
88 
89 	if (nr_cpus > 0)
90 		cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
91 	else
92 		cpus = cpu_map__default_new();
93 out_free_tmp:
94 	free(tmp_cpus);
95 	return cpus;
96 }
97 
98 static struct cpu_map *cpu_map__read_all_cpu_map(void)
99 {
100 	struct cpu_map *cpus = NULL;
101 	FILE *onlnf;
102 
103 	onlnf = fopen("/sys/devices/system/cpu/online", "r");
104 	if (!onlnf)
105 		return cpu_map__default_new();
106 
107 	cpus = cpu_map__read(onlnf);
108 	fclose(onlnf);
109 	return cpus;
110 }
111 
112 struct cpu_map *cpu_map__new(const char *cpu_list)
113 {
114 	struct cpu_map *cpus = NULL;
115 	unsigned long start_cpu, end_cpu = 0;
116 	char *p = NULL;
117 	int i, nr_cpus = 0;
118 	int *tmp_cpus = NULL, *tmp;
119 	int max_entries = 0;
120 
121 	if (!cpu_list)
122 		return cpu_map__read_all_cpu_map();
123 
124 	if (!isdigit(*cpu_list))
125 		goto out;
126 
127 	while (isdigit(*cpu_list)) {
128 		p = NULL;
129 		start_cpu = strtoul(cpu_list, &p, 0);
130 		if (start_cpu >= INT_MAX
131 		    || (*p != '\0' && *p != ',' && *p != '-'))
132 			goto invalid;
133 
134 		if (*p == '-') {
135 			cpu_list = ++p;
136 			p = NULL;
137 			end_cpu = strtoul(cpu_list, &p, 0);
138 
139 			if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
140 				goto invalid;
141 
142 			if (end_cpu < start_cpu)
143 				goto invalid;
144 		} else {
145 			end_cpu = start_cpu;
146 		}
147 
148 		for (; start_cpu <= end_cpu; start_cpu++) {
149 			/* check for duplicates */
150 			for (i = 0; i < nr_cpus; i++)
151 				if (tmp_cpus[i] == (int)start_cpu)
152 					goto invalid;
153 
154 			if (nr_cpus == max_entries) {
155 				max_entries += MAX_NR_CPUS;
156 				tmp = realloc(tmp_cpus, max_entries * sizeof(int));
157 				if (tmp == NULL)
158 					goto invalid;
159 				tmp_cpus = tmp;
160 			}
161 			tmp_cpus[nr_cpus++] = (int)start_cpu;
162 		}
163 		if (*p)
164 			++p;
165 
166 		cpu_list = p;
167 	}
168 
169 	if (nr_cpus > 0)
170 		cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
171 	else
172 		cpus = cpu_map__default_new();
173 invalid:
174 	free(tmp_cpus);
175 out:
176 	return cpus;
177 }
178 
179 size_t cpu_map__fprintf(struct cpu_map *map, FILE *fp)
180 {
181 	int i;
182 	size_t printed = fprintf(fp, "%d cpu%s: ",
183 				 map->nr, map->nr > 1 ? "s" : "");
184 	for (i = 0; i < map->nr; ++i)
185 		printed += fprintf(fp, "%s%d", i ? ", " : "", map->map[i]);
186 
187 	return printed + fprintf(fp, "\n");
188 }
189 
190 struct cpu_map *cpu_map__dummy_new(void)
191 {
192 	struct cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(int));
193 
194 	if (cpus != NULL) {
195 		cpus->nr = 1;
196 		cpus->map[0] = -1;
197 	}
198 
199 	return cpus;
200 }
201 
202 void cpu_map__delete(struct cpu_map *map)
203 {
204 	free(map);
205 }
206 
207 int cpu_map__get_socket(struct cpu_map *map, int idx)
208 {
209 	FILE *fp;
210 	const char *mnt;
211 	char path[PATH_MAX];
212 	int cpu, ret;
213 
214 	if (idx > map->nr)
215 		return -1;
216 
217 	cpu = map->map[idx];
218 
219 	mnt = sysfs__mountpoint();
220 	if (!mnt)
221 		return -1;
222 
223 	snprintf(path, PATH_MAX,
224 		"%s/devices/system/cpu/cpu%d/topology/physical_package_id",
225 		mnt, cpu);
226 
227 	fp = fopen(path, "r");
228 	if (!fp)
229 		return -1;
230 	ret = fscanf(fp, "%d", &cpu);
231 	fclose(fp);
232 	return ret == 1 ? cpu : -1;
233 }
234 
235 static int cmp_ids(const void *a, const void *b)
236 {
237 	return *(int *)a - *(int *)b;
238 }
239 
240 static int cpu_map__build_map(struct cpu_map *cpus, struct cpu_map **res,
241 			      int (*f)(struct cpu_map *map, int cpu))
242 {
243 	struct cpu_map *c;
244 	int nr = cpus->nr;
245 	int cpu, s1, s2;
246 
247 	/* allocate as much as possible */
248 	c = calloc(1, sizeof(*c) + nr * sizeof(int));
249 	if (!c)
250 		return -1;
251 
252 	for (cpu = 0; cpu < nr; cpu++) {
253 		s1 = f(cpus, cpu);
254 		for (s2 = 0; s2 < c->nr; s2++) {
255 			if (s1 == c->map[s2])
256 				break;
257 		}
258 		if (s2 == c->nr) {
259 			c->map[c->nr] = s1;
260 			c->nr++;
261 		}
262 	}
263 	/* ensure we process id in increasing order */
264 	qsort(c->map, c->nr, sizeof(int), cmp_ids);
265 
266 	*res = c;
267 	return 0;
268 }
269 
270 int cpu_map__get_core(struct cpu_map *map, int idx)
271 {
272 	FILE *fp;
273 	const char *mnt;
274 	char path[PATH_MAX];
275 	int cpu, ret, s;
276 
277 	if (idx > map->nr)
278 		return -1;
279 
280 	cpu = map->map[idx];
281 
282 	mnt = sysfs__mountpoint();
283 	if (!mnt)
284 		return -1;
285 
286 	snprintf(path, PATH_MAX,
287 		"%s/devices/system/cpu/cpu%d/topology/core_id",
288 		mnt, cpu);
289 
290 	fp = fopen(path, "r");
291 	if (!fp)
292 		return -1;
293 	ret = fscanf(fp, "%d", &cpu);
294 	fclose(fp);
295 	if (ret != 1)
296 		return -1;
297 
298 	s = cpu_map__get_socket(map, idx);
299 	if (s == -1)
300 		return -1;
301 
302 	/*
303 	 * encode socket in upper 16 bits
304 	 * core_id is relative to socket, and
305 	 * we need a global id. So we combine
306 	 * socket+ core id
307 	 */
308 	return (s << 16) | (cpu & 0xffff);
309 }
310 
311 int cpu_map__build_socket_map(struct cpu_map *cpus, struct cpu_map **sockp)
312 {
313 	return cpu_map__build_map(cpus, sockp, cpu_map__get_socket);
314 }
315 
316 int cpu_map__build_core_map(struct cpu_map *cpus, struct cpu_map **corep)
317 {
318 	return cpu_map__build_map(cpus, corep, cpu_map__get_core);
319 }
320