xref: /openbmc/linux/tools/perf/util/cpumap.c (revision 63dc02bd)
1 #include "util.h"
2 #include "../perf.h"
3 #include "cpumap.h"
4 #include <assert.h>
5 #include <stdio.h>
6 
7 static struct cpu_map *cpu_map__default_new(void)
8 {
9 	struct cpu_map *cpus;
10 	int nr_cpus;
11 
12 	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
13 	if (nr_cpus < 0)
14 		return NULL;
15 
16 	cpus = malloc(sizeof(*cpus) + nr_cpus * sizeof(int));
17 	if (cpus != NULL) {
18 		int i;
19 		for (i = 0; i < nr_cpus; ++i)
20 			cpus->map[i] = i;
21 
22 		cpus->nr = nr_cpus;
23 	}
24 
25 	return cpus;
26 }
27 
28 static struct cpu_map *cpu_map__trim_new(int nr_cpus, int *tmp_cpus)
29 {
30 	size_t payload_size = nr_cpus * sizeof(int);
31 	struct cpu_map *cpus = malloc(sizeof(*cpus) + payload_size);
32 
33 	if (cpus != NULL) {
34 		cpus->nr = nr_cpus;
35 		memcpy(cpus->map, tmp_cpus, payload_size);
36 	}
37 
38 	return cpus;
39 }
40 
41 static struct cpu_map *cpu_map__read_all_cpu_map(void)
42 {
43 	struct cpu_map *cpus = NULL;
44 	FILE *onlnf;
45 	int nr_cpus = 0;
46 	int *tmp_cpus = NULL, *tmp;
47 	int max_entries = 0;
48 	int n, cpu, prev;
49 	char sep;
50 
51 	onlnf = fopen("/sys/devices/system/cpu/online", "r");
52 	if (!onlnf)
53 		return cpu_map__default_new();
54 
55 	sep = 0;
56 	prev = -1;
57 	for (;;) {
58 		n = fscanf(onlnf, "%u%c", &cpu, &sep);
59 		if (n <= 0)
60 			break;
61 		if (prev >= 0) {
62 			int new_max = nr_cpus + cpu - prev - 1;
63 
64 			if (new_max >= max_entries) {
65 				max_entries = new_max + MAX_NR_CPUS / 2;
66 				tmp = realloc(tmp_cpus, max_entries * sizeof(int));
67 				if (tmp == NULL)
68 					goto out_free_tmp;
69 				tmp_cpus = tmp;
70 			}
71 
72 			while (++prev < cpu)
73 				tmp_cpus[nr_cpus++] = prev;
74 		}
75 		if (nr_cpus == max_entries) {
76 			max_entries += MAX_NR_CPUS;
77 			tmp = realloc(tmp_cpus, max_entries * sizeof(int));
78 			if (tmp == NULL)
79 				goto out_free_tmp;
80 			tmp_cpus = tmp;
81 		}
82 
83 		tmp_cpus[nr_cpus++] = cpu;
84 		if (n == 2 && sep == '-')
85 			prev = cpu;
86 		else
87 			prev = -1;
88 		if (n == 1 || sep == '\n')
89 			break;
90 	}
91 
92 	if (nr_cpus > 0)
93 		cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
94 	else
95 		cpus = cpu_map__default_new();
96 out_free_tmp:
97 	free(tmp_cpus);
98 	fclose(onlnf);
99 	return cpus;
100 }
101 
102 struct cpu_map *cpu_map__new(const char *cpu_list)
103 {
104 	struct cpu_map *cpus = NULL;
105 	unsigned long start_cpu, end_cpu = 0;
106 	char *p = NULL;
107 	int i, nr_cpus = 0;
108 	int *tmp_cpus = NULL, *tmp;
109 	int max_entries = 0;
110 
111 	if (!cpu_list)
112 		return cpu_map__read_all_cpu_map();
113 
114 	if (!isdigit(*cpu_list))
115 		goto out;
116 
117 	while (isdigit(*cpu_list)) {
118 		p = NULL;
119 		start_cpu = strtoul(cpu_list, &p, 0);
120 		if (start_cpu >= INT_MAX
121 		    || (*p != '\0' && *p != ',' && *p != '-'))
122 			goto invalid;
123 
124 		if (*p == '-') {
125 			cpu_list = ++p;
126 			p = NULL;
127 			end_cpu = strtoul(cpu_list, &p, 0);
128 
129 			if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
130 				goto invalid;
131 
132 			if (end_cpu < start_cpu)
133 				goto invalid;
134 		} else {
135 			end_cpu = start_cpu;
136 		}
137 
138 		for (; start_cpu <= end_cpu; start_cpu++) {
139 			/* check for duplicates */
140 			for (i = 0; i < nr_cpus; i++)
141 				if (tmp_cpus[i] == (int)start_cpu)
142 					goto invalid;
143 
144 			if (nr_cpus == max_entries) {
145 				max_entries += MAX_NR_CPUS;
146 				tmp = realloc(tmp_cpus, max_entries * sizeof(int));
147 				if (tmp == NULL)
148 					goto invalid;
149 				tmp_cpus = tmp;
150 			}
151 			tmp_cpus[nr_cpus++] = (int)start_cpu;
152 		}
153 		if (*p)
154 			++p;
155 
156 		cpu_list = p;
157 	}
158 
159 	if (nr_cpus > 0)
160 		cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
161 	else
162 		cpus = cpu_map__default_new();
163 invalid:
164 	free(tmp_cpus);
165 out:
166 	return cpus;
167 }
168 
169 size_t cpu_map__fprintf(struct cpu_map *map, FILE *fp)
170 {
171 	int i;
172 	size_t printed = fprintf(fp, "%d cpu%s: ",
173 				 map->nr, map->nr > 1 ? "s" : "");
174 	for (i = 0; i < map->nr; ++i)
175 		printed += fprintf(fp, "%s%d", i ? ", " : "", map->map[i]);
176 
177 	return printed + fprintf(fp, "\n");
178 }
179 
180 struct cpu_map *cpu_map__dummy_new(void)
181 {
182 	struct cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(int));
183 
184 	if (cpus != NULL) {
185 		cpus->nr = 1;
186 		cpus->map[0] = -1;
187 	}
188 
189 	return cpus;
190 }
191 
192 void cpu_map__delete(struct cpu_map *map)
193 {
194 	free(map);
195 }
196