xref: /openbmc/linux/tools/perf/util/util.c (revision 05bcf503)
1 #include "../perf.h"
2 #include "util.h"
3 #include <sys/mman.h>
4 #ifdef BACKTRACE_SUPPORT
5 #include <execinfo.h>
6 #endif
7 #include <stdio.h>
8 #include <stdlib.h>
9 
10 /*
11  * XXX We need to find a better place for these things...
12  */
13 bool perf_host  = true;
14 bool perf_guest = false;
15 
16 void event_attr_init(struct perf_event_attr *attr)
17 {
18 	if (!perf_host)
19 		attr->exclude_host  = 1;
20 	if (!perf_guest)
21 		attr->exclude_guest = 1;
22 	/* to capture ABI version */
23 	attr->size = sizeof(*attr);
24 }
25 
26 int mkdir_p(char *path, mode_t mode)
27 {
28 	struct stat st;
29 	int err;
30 	char *d = path;
31 
32 	if (*d != '/')
33 		return -1;
34 
35 	if (stat(path, &st) == 0)
36 		return 0;
37 
38 	while (*++d == '/');
39 
40 	while ((d = strchr(d, '/'))) {
41 		*d = '\0';
42 		err = stat(path, &st) && mkdir(path, mode);
43 		*d++ = '/';
44 		if (err)
45 			return -1;
46 		while (*d == '/')
47 			++d;
48 	}
49 	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
50 }
51 
52 static int slow_copyfile(const char *from, const char *to)
53 {
54 	int err = 0;
55 	char *line = NULL;
56 	size_t n;
57 	FILE *from_fp = fopen(from, "r"), *to_fp;
58 
59 	if (from_fp == NULL)
60 		goto out;
61 
62 	to_fp = fopen(to, "w");
63 	if (to_fp == NULL)
64 		goto out_fclose_from;
65 
66 	while (getline(&line, &n, from_fp) > 0)
67 		if (fputs(line, to_fp) == EOF)
68 			goto out_fclose_to;
69 	err = 0;
70 out_fclose_to:
71 	fclose(to_fp);
72 	free(line);
73 out_fclose_from:
74 	fclose(from_fp);
75 out:
76 	return err;
77 }
78 
79 int copyfile(const char *from, const char *to)
80 {
81 	int fromfd, tofd;
82 	struct stat st;
83 	void *addr;
84 	int err = -1;
85 
86 	if (stat(from, &st))
87 		goto out;
88 
89 	if (st.st_size == 0) /* /proc? do it slowly... */
90 		return slow_copyfile(from, to);
91 
92 	fromfd = open(from, O_RDONLY);
93 	if (fromfd < 0)
94 		goto out;
95 
96 	tofd = creat(to, 0755);
97 	if (tofd < 0)
98 		goto out_close_from;
99 
100 	addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fromfd, 0);
101 	if (addr == MAP_FAILED)
102 		goto out_close_to;
103 
104 	if (write(tofd, addr, st.st_size) == st.st_size)
105 		err = 0;
106 
107 	munmap(addr, st.st_size);
108 out_close_to:
109 	close(tofd);
110 	if (err)
111 		unlink(to);
112 out_close_from:
113 	close(fromfd);
114 out:
115 	return err;
116 }
117 
118 unsigned long convert_unit(unsigned long value, char *unit)
119 {
120 	*unit = ' ';
121 
122 	if (value > 1000) {
123 		value /= 1000;
124 		*unit = 'K';
125 	}
126 
127 	if (value > 1000) {
128 		value /= 1000;
129 		*unit = 'M';
130 	}
131 
132 	if (value > 1000) {
133 		value /= 1000;
134 		*unit = 'G';
135 	}
136 
137 	return value;
138 }
139 
140 int readn(int fd, void *buf, size_t n)
141 {
142 	void *buf_start = buf;
143 
144 	while (n) {
145 		int ret = read(fd, buf, n);
146 
147 		if (ret <= 0)
148 			return ret;
149 
150 		n -= ret;
151 		buf += ret;
152 	}
153 
154 	return buf - buf_start;
155 }
156 
157 size_t hex_width(u64 v)
158 {
159 	size_t n = 1;
160 
161 	while ((v >>= 4))
162 		++n;
163 
164 	return n;
165 }
166 
167 /* Obtain a backtrace and print it to stdout. */
168 #ifdef BACKTRACE_SUPPORT
169 void dump_stack(void)
170 {
171 	void *array[16];
172 	size_t size = backtrace(array, ARRAY_SIZE(array));
173 	char **strings = backtrace_symbols(array, size);
174 	size_t i;
175 
176 	printf("Obtained %zd stack frames.\n", size);
177 
178 	for (i = 0; i < size; i++)
179 		printf("%s\n", strings[i]);
180 
181 	free(strings);
182 }
183 #else
184 void dump_stack(void) {}
185 #endif
186