1 /* vi: set sw=4 ts=4: */
2 /*
3 * readprofile.c - used to read /proc/profile
4 *
5 * Copyright (C) 1994,1996 Alessandro Rubini (rubini@ipvvis.unipv.it)
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 */
9
10 /*
11 * 1999-02-22 Arkadiusz Mickiewicz <misiek@pld.ORG.PL>
12 * - added Native Language Support
13 * 1999-09-01 Stephane Eranian <eranian@cello.hpl.hp.com>
14 * - 64bit clean patch
15 * 3Feb2001 Andrew Morton <andrewm@uow.edu.au>
16 * - -M option to write profile multiplier.
17 * 2001-11-07 Werner Almesberger <wa@almesberger.net>
18 * - byte order auto-detection and -n option
19 * 2001-11-09 Werner Almesberger <wa@almesberger.net>
20 * - skip step size (index 0)
21 * 2002-03-09 John Levon <moz@compsoc.man.ac.uk>
22 * - make maplineno do something
23 * 2002-11-28 Mads Martin Joergensen +
24 * - also try /boot/System.map-`uname -r`
25 * 2003-04-09 Werner Almesberger <wa@almesberger.net>
26 * - fixed off-by eight error and improved heuristics in byte order detection
27 * 2003-08-12 Nikita Danilov <Nikita@Namesys.COM>
28 * - added -s option; example of use:
29 * "readprofile -s -m /boot/System.map-test | grep __d_lookup | sort -n -k3"
30 *
31 * Taken from util-linux and adapted for busybox by
32 * Paul Mundt <lethal@linux-sh.org>.
33 */
34 //config:config READPROFILE
35 //config: bool "readprofile (7.1 kb)"
36 //config: default y
37 //config: help
38 //config: This allows you to parse /proc/profile for basic profiling.
39
40 //applet:IF_READPROFILE(APPLET(readprofile, BB_DIR_USR_SBIN, BB_SUID_DROP))
41
42 //kbuild:lib-$(CONFIG_READPROFILE) += readprofile.o
43
44 //usage:#define readprofile_trivial_usage
45 //usage: "[OPTIONS]"
46 //usage:#define readprofile_full_usage "\n\n"
47 //usage: " -m MAPFILE (Default: /boot/System.map)"
48 //usage: "\n -p PROFILE (Default: /proc/profile)"
49 //usage: "\n -M NUM Set the profiling multiplier to NUM"
50 //usage: "\n -i Print only info about the sampling step"
51 //usage: "\n -v Verbose"
52 //usage: "\n -a Print all symbols, even if count is 0"
53 //usage: "\n -b Print individual histogram-bin counts"
54 //usage: "\n -s Print individual counters within functions"
55 //usage: "\n -r Reset all the counters (root only)"
56 //usage: "\n -n Disable byte order auto-detection"
57
58 #include "libbb.h"
59 #include <sys/utsname.h>
60
61 #define S_LEN 128
62
63 int readprofile_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
readprofile_main(int argc UNUSED_PARAM,char ** argv)64 int readprofile_main(int argc UNUSED_PARAM, char **argv)
65 {
66 FILE *map;
67 const char *mapFile, *proFile;
68 unsigned long indx;
69 size_t len;
70 uint64_t add0;
71 unsigned int step;
72 unsigned int *buf, total, fn_len;
73 unsigned long long fn_add, next_add; /* current and next address */
74 char fn_name[S_LEN], next_name[S_LEN]; /* current and next name */
75 char mapline[S_LEN];
76 char mode[8];
77 int maplineno;
78 int multiplier;
79 unsigned opt;
80 enum {
81 OPT_M = (1 << 0),
82 OPT_m = (1 << 1),
83 OPT_p = (1 << 2),
84 OPT_n = (1 << 3),
85 OPT_a = (1 << 4),
86 OPT_b = (1 << 5),
87 OPT_s = (1 << 6),
88 OPT_i = (1 << 7),
89 OPT_r = (1 << 8),
90 OPT_v = (1 << 9),
91 };
92 #define optMult (opt & OPT_M)
93 #define optNative (opt & OPT_n)
94 #define optAll (opt & OPT_a)
95 #define optBins (opt & OPT_b)
96 #define optSub (opt & OPT_s)
97 #define optInfo (opt & OPT_i)
98 #define optReset (opt & OPT_r)
99 #define optVerbose (opt & OPT_v)
100
101 #define next (current^1)
102
103 proFile = "/proc/profile";
104 mapFile = "/boot/System.map";
105 multiplier = 0;
106
107 opt = getopt32(argv, "M:+m:p:nabsirv", &multiplier, &mapFile, &proFile);
108
109 if (opt & (OPT_M|OPT_r)) { /* mult or reset, or both */
110 int fd, to_write;
111
112 /*
113 * When writing the multiplier, if the length of the write is
114 * not sizeof(int), the multiplier is not changed
115 */
116 to_write = sizeof(int);
117 if (!optMult)
118 to_write = 1; /* sth different from sizeof(int) */
119
120 fd = xopen("/proc/profile", O_WRONLY);
121 xwrite(fd, &multiplier, to_write);
122 close(fd);
123 return EXIT_SUCCESS;
124 }
125
126 /*
127 * Use an fd for the profiling buffer, to skip stdio overhead
128 */
129 len = MAXINT(ssize_t);
130 buf = xmalloc_xopen_read_close(proFile, &len);
131 len /= sizeof(*buf);
132
133 if (!optNative) {
134 int big = 0, small = 0;
135 unsigned *p;
136
137 for (p = buf+1; p < buf+len; p++) {
138 if (*p & ~0U << (sizeof(*buf)*4))
139 big++;
140 if (*p & ((1 << (sizeof(*buf)*4))-1))
141 small++;
142 }
143 if (big > small) {
144 bb_simple_error_msg("assuming reversed byte order, "
145 "use -n to force native byte order");
146 BUILD_BUG_ON(sizeof(*p) > 8);
147 for (p = buf; p < buf+len; p++) {
148 if (sizeof(*p) == 2)
149 *p = bswap_16(*p);
150 if (sizeof(*p) == 4)
151 *p = bswap_32(*p);
152 if (sizeof(*p) == 8)
153 *p = bb_bswap_64(*p);
154 }
155 }
156 }
157
158 step = buf[0];
159 if (optInfo) {
160 printf("Sampling_step: %u\n", step);
161 return EXIT_SUCCESS;
162 }
163
164 map = xfopen_for_read(mapFile);
165 add0 = 0;
166 maplineno = 1;
167 while (fgets(mapline, S_LEN, map)) {
168 if (sscanf(mapline, "%llx %s %s", &fn_add, mode, fn_name) != 3)
169 bb_error_msg_and_die("%s(%i): wrong map line",
170 mapFile, maplineno);
171
172 if (strcmp(fn_name, "_stext") == 0) /* only elf works like this */ {
173 add0 = fn_add;
174 break;
175 }
176 maplineno++;
177 }
178
179 if (!add0)
180 bb_error_msg_and_die("can't find \"_stext\" in %s", mapFile);
181
182 /*
183 * Main loop.
184 */
185 total = 0;
186 indx = 1;
187 while (fgets(mapline, S_LEN, map)) {
188 bool header_printed;
189 unsigned int this;
190
191 if (sscanf(mapline, "%llx %s %s", &next_add, mode, next_name) != 3)
192 bb_error_msg_and_die("%s(%i): wrong map line",
193 mapFile, maplineno);
194
195 header_printed = 0;
196
197 /* ignore any LEADING (before a '[tT]' symbol is found)
198 Absolute symbols */
199 if ((mode[0] == 'A' || mode[0] == '?') && total == 0)
200 continue;
201 if ((mode[0]|0x20) != 't' && (mode[0]|0x20) != 'w') {
202 break; /* only text is profiled */
203 }
204
205 if (indx >= len)
206 bb_simple_error_msg_and_die("profile address out of range. "
207 "Wrong map file?");
208
209 this = 0;
210 while (indx < (next_add-add0)/step) {
211 if (optBins && (buf[indx] || optAll)) {
212 if (!header_printed) {
213 printf("%s:\n", fn_name);
214 header_printed = 1;
215 }
216 printf("\t%"PRIx64"\t%u\n", (indx - 1)*step + add0, buf[indx]);
217 }
218 this += buf[indx++];
219 }
220 total += this;
221
222 if (optBins) {
223 if (optVerbose || this > 0)
224 printf(" total\t\t\t\t%u\n", this);
225 } else
226 if ((this || optAll)
227 && (fn_len = next_add-fn_add) != 0
228 ) {
229 if (optVerbose)
230 printf("%016llx %-40s %6u %8.4f\n", fn_add,
231 fn_name, this, this/(double)fn_len);
232 else
233 printf("%6u %-40s %8.4f\n",
234 this, fn_name, this/(double)fn_len);
235 if (optSub) {
236 unsigned long long scan;
237
238 for (scan = (fn_add-add0)/step + 1;
239 scan < (next_add-add0)/step; scan++) {
240 unsigned long long addr;
241
242 addr = (scan - 1)*step + add0;
243 printf("\t%#llx\t%s+%#llx\t%u\n",
244 addr, fn_name, addr - fn_add,
245 buf[scan]);
246 }
247 }
248 }
249
250 fn_add = next_add;
251 strcpy(fn_name, next_name);
252
253 maplineno++;
254 }
255
256 /* clock ticks, out of kernel text - probably modules */
257 printf("%6u *unknown*\n", buf[len-1]);
258
259 /* trailer */
260 if (optVerbose)
261 printf("%016x %-40s %6u %8.4f\n",
262 0, "total", total, total/(double)(fn_add-add0));
263 else
264 printf("%6u %-40s %8.4f\n",
265 total, "total", total/(double)(fn_add-add0));
266
267 if (ENABLE_FEATURE_CLEAN_UP) {
268 fclose(map);
269 free(buf);
270 }
271
272 return EXIT_SUCCESS;
273 }
274