summaryrefslogtreecommitdiff
path: root/util-linux/readprofile.c
blob: b4cb5804f751477e6ed23e4aad3900c08136c573 (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
/* vi: set sw=4 ts=4: */
/*
 *  readprofile.c - used to read /proc/profile
 *
 *  Copyright (C) 1994,1996 Alessandro Rubini (rubini@ipvvis.unipv.it)
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

/*
 * 1999-02-22 Arkadiusz Mickiewicz <misiek@pld.ORG.PL>
 * - added Native Language Support
 * 1999-09-01 Stephane Eranian <eranian@cello.hpl.hp.com>
 * - 64bit clean patch
 * 3Feb2001 Andrew Morton <andrewm@uow.edu.au>
 * - -M option to write profile multiplier.
 * 2001-11-07 Werner Almesberger <wa@almesberger.net>
 * - byte order auto-detection and -n option
 * 2001-11-09 Werner Almesberger <wa@almesberger.net>
 * - skip step size (index 0)
 * 2002-03-09 John Levon <moz@compsoc.man.ac.uk>
 * - make maplineno do something
 * 2002-11-28 Mads Martin Joergensen +
 * - also try /boot/System.map-`uname -r`
 * 2003-04-09 Werner Almesberger <wa@almesberger.net>
 * - fixed off-by eight error and improved heuristics in byte order detection
 * 2003-08-12 Nikita Danilov <Nikita@Namesys.COM>
 * - added -s option; example of use:
 * "readprofile -s -m /boot/System.map-test | grep __d_lookup | sort -n -k3"
 *
 * Taken from util-linux and adapted for busybox by
 * Paul Mundt <lethal@linux-sh.org>.
 */
//config:config READPROFILE
//config:	bool "readprofile (7.2 kb)"
//config:	default y
//config:	#select PLATFORM_LINUX
//config:	help
//config:	  This allows you to parse /proc/profile for basic profiling.

//applet:IF_READPROFILE(APPLET(readprofile, BB_DIR_USR_SBIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_READPROFILE) += readprofile.o

//usage:#define readprofile_trivial_usage
//usage:       "[OPTIONS]"
//usage:#define readprofile_full_usage "\n\n"
//usage:       "	-m mapfile	(Default: /boot/System.map)"
//usage:     "\n	-p profile	(Default: /proc/profile)"
//usage:     "\n	-M NUM		Set the profiling multiplier to NUM"
//usage:     "\n	-i		Print only info about the sampling step"
//usage:     "\n	-v		Verbose"
//usage:     "\n	-a		Print all symbols, even if count is 0"
//usage:     "\n	-b		Print individual histogram-bin counts"
//usage:     "\n	-s		Print individual counters within functions"
//usage:     "\n	-r		Reset all the counters (root only)"
//usage:     "\n	-n		Disable byte order auto-detection"

#include "libbb.h"
#include <sys/utsname.h>

#define S_LEN 128

/* These are the defaults */
static const char defaultmap[] ALIGN1 = "/boot/System.map";
static const char defaultpro[] ALIGN1 = "/proc/profile";

int readprofile_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int readprofile_main(int argc UNUSED_PARAM, char **argv)
{
	FILE *map;
	const char *mapFile, *proFile;
	unsigned long indx = 1;
	size_t len;
	uint64_t add0 = 0;
	unsigned int step;
	unsigned int *buf, total, fn_len;
	unsigned long long fn_add, next_add;     /* current and next address */
	char fn_name[S_LEN], next_name[S_LEN];   /* current and next name */
	char mapline[S_LEN];
	char mode[8];
	int maplineno = 1;
	int header_printed;
	int multiplier = 0;
	unsigned opt;
	enum {
		OPT_M = (1 << 0),
		OPT_m = (1 << 1),
		OPT_p = (1 << 2),
		OPT_n = (1 << 3),
		OPT_a = (1 << 4),
		OPT_b = (1 << 5),
		OPT_s = (1 << 6),
		OPT_i = (1 << 7),
		OPT_r = (1 << 8),
		OPT_v = (1 << 9),
	};
#define optMult    (opt & OPT_M)
#define optNative  (opt & OPT_n)
#define optAll     (opt & OPT_a)
#define optBins    (opt & OPT_b)
#define optSub     (opt & OPT_s)
#define optInfo    (opt & OPT_i)
#define optReset   (opt & OPT_r)
#define optVerbose (opt & OPT_v)

#define next (current^1)

	proFile = defaultpro;
	mapFile = defaultmap;

	opt = getopt32(argv, "M:+m:p:nabsirv", &multiplier, &mapFile, &proFile);

	if (opt & (OPT_M|OPT_r)) { /* mult or reset, or both */
		int fd, to_write;

		/*
		 * When writing the multiplier, if the length of the write is
		 * not sizeof(int), the multiplier is not changed
		 */
		to_write = sizeof(int);
		if (!optMult)
			to_write = 1;  /* sth different from sizeof(int) */

		fd = xopen(defaultpro, O_WRONLY);
		xwrite(fd, &multiplier, to_write);
		close(fd);
		return EXIT_SUCCESS;
	}

	/*
	 * Use an fd for the profiling buffer, to skip stdio overhead
	 */
	len = MAXINT(ssize_t);
	buf = xmalloc_xopen_read_close(proFile, &len);
	if (!optNative) {
		int entries = len / sizeof(*buf);
		int big = 0, small = 0, i;
		unsigned *p;

		for (p = buf+1; p < buf+entries; p++) {
			if (*p & ~0U << (sizeof(*buf)*4))
				big++;
			if (*p & ((1 << (sizeof(*buf)*4))-1))
				small++;
		}
		if (big > small) {
			bb_error_msg("assuming reversed byte order, "
				"use -n to force native byte order");
			for (p = buf; p < buf+entries; p++)
				for (i = 0; i < sizeof(*buf)/2; i++) {
					unsigned char *b = (unsigned char *) p;
					unsigned char tmp;

					tmp = b[i];
					b[i] = b[sizeof(*buf)-i-1];
					b[sizeof(*buf)-i-1] = tmp;
				}
		}
	}

	step = buf[0];
	if (optInfo) {
		printf("Sampling_step: %u\n", step);
		return EXIT_SUCCESS;
	}

	total = 0;

	map = xfopen_for_read(mapFile);

	while (fgets(mapline, S_LEN, map)) {
		if (sscanf(mapline, "%llx %s %s", &fn_add, mode, fn_name) != 3)
			bb_error_msg_and_die("%s(%i): wrong map line",
					mapFile, maplineno);

		if (strcmp(fn_name, "_stext") == 0) /* only elf works like this */ {
			add0 = fn_add;
			break;
		}
		maplineno++;
	}

	if (!add0)
		bb_error_msg_and_die("can't find \"_stext\" in %s", mapFile);

	/*
	 * Main loop.
	 */
	while (fgets(mapline, S_LEN, map)) {
		unsigned int this = 0;

		if (sscanf(mapline, "%llx %s %s", &next_add, mode, next_name) != 3)
			bb_error_msg_and_die("%s(%i): wrong map line",
					mapFile, maplineno);

		header_printed = 0;

		/* ignore any LEADING (before a '[tT]' symbol is found)
		   Absolute symbols */
		if ((*mode == 'A' || *mode == '?') && total == 0) continue;
		if (*mode != 'T' && *mode != 't'
		 && *mode != 'W' && *mode != 'w'
		) {
			break;  /* only text is profiled */
		}

		if (indx >= len / sizeof(*buf))
			bb_error_msg_and_die("profile address out of range. "
					"Wrong map file?");

		while (indx < (next_add-add0)/step) {
			if (optBins && (buf[indx] || optAll)) {
				if (!header_printed) {
					printf("%s:\n", fn_name);
					header_printed = 1;
				}
				printf("\t%"PRIx64"\t%u\n", (indx - 1)*step + add0, buf[indx]);
			}
			this += buf[indx++];
		}
		total += this;

		if (optBins) {
			if (optVerbose || this > 0)
				printf("  total\t\t\t\t%u\n", this);
		} else
		if ((this || optAll)
		 && (fn_len = next_add-fn_add) != 0
		) {
			if (optVerbose)
				printf("%016llx %-40s %6u %8.4f\n", fn_add,
					fn_name, this, this/(double)fn_len);
			else
				printf("%6u %-40s %8.4f\n",
					this, fn_name, this/(double)fn_len);
			if (optSub) {
				unsigned long long scan;

				for (scan = (fn_add-add0)/step + 1;
				     scan < (next_add-add0)/step; scan++) {
					unsigned long long addr;

					addr = (scan - 1)*step + add0;
					printf("\t%#llx\t%s+%#llx\t%u\n",
						addr, fn_name, addr - fn_add,
						buf[scan]);
				}
			}
		}

		fn_add = next_add;
		strcpy(fn_name, next_name);

		maplineno++;
	}

	/* clock ticks, out of kernel text - probably modules */
	printf("%6u %s\n", buf[len/sizeof(*buf)-1], "*unknown*");

	/* trailer */
	if (optVerbose)
		printf("%016x %-40s %6u %8.4f\n",
			0, "total", total, total/(double)(fn_add-add0));
	else
		printf("%6u %-40s %8.4f\n",
			total, "total", total/(double)(fn_add-add0));

	fclose(map);
	free(buf);

	return EXIT_SUCCESS;
}