aboutsummaryrefslogtreecommitdiff
path: root/hugectl.c
blob: e2a9828aec6275984727175b5fb9907b313778d0 (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
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
/***************************************************************************
 *   User front end for using huge pages Copyright (C) 2008, IBM           *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the Lesser GNU General Public License as        *
 *   published by the Free Software Foundation; either version 2.1 of the  *
 *   License, or at your option) any later version.                        *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU Lesser General Public License for more details.                   *
 *                                                                         *
 *   You should have received a copy of the Lesser GNU General Public      *
 *   License along with this program; if not, write to the                 *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

/*
 * hugectl is inspired by numactl as a single front end to a large number of
 * options for controlling a very specific environment.  Eventually it will
 * have support for controlling the all of the environment variables for
 * libhugetlbfs, but options will only be added after they have been in the
 * library for some time and are throughly tested and stable.
 *
 * This program should be treated as an ABI for using libhugetlbfs.
 */

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <limits.h>

#define _GNU_SOURCE /* for getopt_long */
#include <unistd.h>
#include <getopt.h>

#define REPORT(level, prefix, format, ...)				      \
	do {								      \
		if (verbose_level >= level)				      \
			fprintf(stderr, "hugectl: " prefix ": " format,	      \
				##__VA_ARGS__);				      \
	} while (0);

#include "libhugetlbfs_debug.h"

extern int errno;
extern int optind;
extern char *optarg;

#define OPTION(opts, text)	fprintf(stderr, " %-25s  %s\n", opts, text)
#define CONT(text) 		fprintf(stderr, " %-25s  %s\n", "", text)

void print_usage()
{
	fprintf(stderr, "hugectl [options] target\n");
	fprintf(stderr, "options:\n");

	OPTION("--help, -h", "Prints this message");
	OPTION("--verbose <level>, -v", "Increases/sets tracing levels");

	OPTION("--text[=<size>]", "Requests remapping of the program text");
	OPTION("--data[=<size>]", "Requests remapping of the program data");
	OPTION("--bss[=<size>]", "Requests remapping of the program bss");
	OPTION("--heap[=<size>]", "Requests remapping of the program heap");
	CONT("(malloc space)");
	OPTION("--shm", "Requests remapping of shared memory segments");

	OPTION("--no-preload", "Disable preloading the libhugetlbfs library");
	OPTION("--no-reserve", "Disable huge page reservation for segments");
	OPTION("--force-preload", "Force preloading the libhugetlbfs library");

	OPTION("--dry-run", "describe what would be done without doing it");

	OPTION("--library-use-path", "Use the system library path");
	OPTION("--share-text", "Share text segments between multiple");
	CONT("application instances");
	OPTION("--library-path <path>", "Select a library prefix");
	CONT("(Default: "
#ifdef LIBDIR32
		LIBDIR32 ":"
#endif
#ifdef LIBDIR32
		LIBDIR32 ":"
#endif
		")");
}

int opt_dry_run = 0;
int opt_force_preload = 0;
int verbose_level = VERBOSITY_DEFAULT;

void verbose_init(void)
{
	char *env;

	env = getenv("HUGETLB_VERBOSE");
	if (env)
		verbose_level = atoi(env);
	env = getenv("HUGETLB_DEBUG");
	if (env)
		verbose_level = VERBOSITY_MAX;
}

void verbose(char *which)
{
	int new_level;

	if (which) {
		new_level = atoi(which);
		if (new_level < 0 || new_level > 99) {
			ERROR("%d: verbosity out of range 0-99\n",
				new_level);
			exit(EXIT_FAILURE);
		}
	} else {
		new_level = verbose_level + 1;
		if (new_level == 100) {
			WARNING("verbosity limited to 99\n");
			new_level--;
		}
	}
	verbose_level = new_level;
}

void quiet(void)
{
	int new_level = verbose_level - 1;
	if (new_level < 0) {
		WARNING("verbosity must be at least 0\n");
		new_level = 0;
	}
	verbose_level = new_level;
}

void setup_environment(char *var, char *val)
{
	setenv(var, val, 1);
	INFO("%s='%s'\n", var, val);

	if (opt_dry_run)
		printf("%s='%s'\n", var, val);
}

void verbose_expose(void)
{
	char level[3];

	if (verbose_level == 99) {
		setup_environment("HUGETLB_DEBUG", "yes");
	}
	snprintf(level, sizeof(level), "%d", verbose_level);
	setup_environment("HUGETLB_VERBOSE", level);
}

/*
 * getopts return values for options which are long only.
 */
#define MAP_BASE	0x1000
#define LONG_BASE	0x2000

#define LONG_NO_PRELOAD		(LONG_BASE | 'p')
#define LONG_NO_RESERVE		(LONG_BASE | 'r')
#define LONG_FORCE_PRELOAD	(LONG_BASE | 'F')

#define LONG_DRY_RUN		(LONG_BASE | 'd')

#define LONG_SHARE		(LONG_BASE | 's')
#define LONG_NO_LIBRARY		(LONG_BASE | 'L')
#define LONG_LIBRARY		(LONG_BASE | 'l')

/*
 * Mapping selectors, one per remappable/backable area as requested
 * by the user.  These are also used as returns from getopts where they
 * are offset from MAP_BASE, which must be removed before they are compared.
 */
enum {
	MAP_TEXT,
	MAP_DATA,
	MAP_BSS,
	MAP_HEAP,
	MAP_SHM,
	MAP_DISABLE,

	MAP_COUNT,
};
char *map_size[MAP_COUNT];

char default_size[] = "the default hugepage size";
#define DEFAULT_SIZE default_size

#define available(buf, ptr) ((int)(sizeof(buf) - (ptr - buf)))
void setup_mappings(int count)
{
	char value[128];
	char *ptr = value;
	int needed;

	/*
	 * HUGETLB_ELFMAP should be set to either a combination of 'R' and 'W'
	 * which indicate which segments should be remapped.  Each may take
	 * an optional page size.  It may also be set to 'no' to prevent
	 * remapping.
	 */

	/*
	 * Accumulate sections each with a ':' prefix to simplify later
	 * handling.  We will elide the initial ':' before use.
	 */
	if (map_size[MAP_TEXT]) {
		if (map_size[MAP_TEXT] == DEFAULT_SIZE)
			needed = snprintf(ptr, available(value, ptr), ":R");
		else
			needed = snprintf(ptr, available(value, ptr),
						":R=%s", map_size[MAP_TEXT]);
		ptr += needed;
		if (needed < 0 || available(value, ptr) < 0) {
			ERROR("%s: bad size specification\n", map_size[MAP_TEXT]);
			exit(EXIT_FAILURE);
		}
	}
	if (map_size[MAP_DATA] != 0 || map_size[MAP_BSS] != 0) {
		char *size = map_size[MAP_BSS];
		if (map_size[MAP_DATA])
			size = map_size[MAP_DATA];
		if (map_size[MAP_DATA] != map_size[MAP_BSS])
			WARNING("data and bss remapped together in %s\n", size);

		if (size == DEFAULT_SIZE)
			needed = snprintf(ptr, available(value, ptr), ":W");
		else
			needed = snprintf(ptr, available(value, ptr),
						":W=%s", size);
		ptr += needed;
		if (needed < 0 || available(value, ptr) < 0) {
			ERROR("%s: bad size specification\n", size);
			exit(EXIT_FAILURE);
		}
	}
	*ptr = '\0';
	if (ptr != value)
		setup_environment("HUGETLB_ELFMAP", &value[1]);

	if (map_size[MAP_DISABLE]) {
		if (ptr != value)
			WARNING("--disable masks requested remap\n");
		setup_environment("HUGETLB_ELFMAP", "no");
	}

	if (map_size[MAP_HEAP] == DEFAULT_SIZE)
		setup_environment("HUGETLB_MORECORE", "yes");
	else if (map_size[MAP_HEAP])
		setup_environment("HUGETLB_MORECORE", map_size[MAP_HEAP]);

	if (map_size[MAP_SHM] && map_size[MAP_SHM] != DEFAULT_SIZE)
		WARNING("shm segments may only be mapped in the "
			"default hugepage size\n");
	if (map_size[MAP_SHM])
		setup_environment("HUGETLB_SHM", "yes");
}

#define LIBRARY_DISABLE ((void *)-1)

void library_path(char *path)
{
	char val[NAME_MAX] = "";
	char *env;

	env = getenv("LD_LIBRARY_PATH");

	/*
	 * Select which libraries we wish to use.  If the path is NULL
	 * use the libraries included with hugectl.  If the path is valid
	 * and points to a directory including a libhugetlbfs.so use it
	 * directly.  Else path is assumed to be a prefix to the 32/64 bit
	 * directories both of which are added, where available.
	 */
	if (path) {
		snprintf(val, sizeof(val), "%s/libhugetlbfs.so", path);
		if (access(val, F_OK) == 0) {
			/* $PATH */
			snprintf(val, sizeof(val), "%s:%s",
				path, env ? env : "");

		} else {
			/* [$PATH/LIB32:][$PATH/LIB64:]$LD_LIBRARY_PATH */
			snprintf(val, sizeof(val), ""
#ifdef LIBDIR32
				"%s/" LIB32 ":"
#endif
#ifdef LIBDIR64
				"%s/" LIB64 ":"
#endif
				"%s",
#ifdef LIBDIR32
				path,
#endif
#ifdef LIBDIR64
				path,
#endif
				env ? env : "");
		}

	} else {
		/* [LIBDIR32:][LIBDIR64:]$LD_LIBRARY_PATH */
		snprintf(val, sizeof(val), ""
#ifdef LIBDIR32
			LIBDIR32 ":"
#endif
#ifdef LIBDIR64
			LIBDIR64 ":"
#endif
			"%s", env ? env : "");
	}
	setup_environment("LD_LIBRARY_PATH", val);
}

void ldpreload(int count)
{
	int allowed = 0;

	if (map_size[MAP_HEAP])
		allowed++;
	if (map_size[MAP_SHM])
		allowed++;

	if ((allowed == count) || opt_force_preload) {
		setup_environment("LD_PRELOAD", "libhugetlbfs.so");
		if (allowed == count)
			INFO("LD_PRELOAD in use for lone --heap/--shm\n");
	} else {
		WARNING("LD_PRELOAD not appropriate for this map combination\n");
	}
}

int main(int argc, char** argv)
{
	int opt_mappings = 0;
	int opt_preload = 1;
	int opt_no_reserve = 0;
	int opt_share = 0;
	char *opt_library = NULL;

	char opts[] = "+hvq";
	int ret = 0, index = 0;
	struct option long_opts[] = {
		{"help",       no_argument, NULL, 'h'},
		{"verbose",    required_argument, NULL, 'v' },
		{"no-preload", no_argument, NULL, LONG_NO_PRELOAD},
		{"no-reserve", no_argument, NULL, LONG_NO_RESERVE},
		{"force-preload",
			       no_argument, NULL, LONG_FORCE_PRELOAD},
		{"dry-run",    no_argument, NULL, LONG_DRY_RUN},
		{"library-path",
			       required_argument, NULL, LONG_LIBRARY},
		{"library-use-path",
			       no_argument, NULL, LONG_NO_LIBRARY},
		{"share-text", no_argument, NULL, LONG_SHARE},

		{"disable",    optional_argument, NULL, MAP_BASE|MAP_DISABLE},
		{"text",       optional_argument, NULL, MAP_BASE|MAP_TEXT},
		{"data",       optional_argument, NULL, MAP_BASE|MAP_DATA},
		{"bss",        optional_argument, NULL, MAP_BASE|MAP_BSS},
		{"heap",       optional_argument, NULL, MAP_BASE|MAP_HEAP},
		{"shm",        optional_argument, NULL, MAP_BASE|MAP_SHM},

		{0},
	};

	verbose_init();

	while (ret != -1) {
		ret = getopt_long(argc, argv, opts, long_opts, &index);
		if (ret > 0 && (ret & MAP_BASE)) {
			if (optarg)
				map_size[ret & ~MAP_BASE] = optarg;
			else
				map_size[ret & ~MAP_BASE] = DEFAULT_SIZE;
			opt_mappings++;
			continue;
		}
		switch (ret) {
		case '?':
			print_usage();
			exit(EXIT_FAILURE);

		case 'h':
			print_usage();
			exit(EXIT_SUCCESS);

		case 'v':
			verbose(optarg);
			break;

		case 'q':
			quiet();
			break;

		case LONG_NO_PRELOAD:
			opt_preload = 0;
			INFO("LD_PRELOAD disabled\n");
			break;

		case LONG_NO_RESERVE:
			opt_no_reserve = 1;
			INFO("MAP_NORESERVE used for huge page mappings\n");
			break;

		case LONG_FORCE_PRELOAD:
			opt_preload = 1;
			opt_force_preload = 1;
			INFO("Forcing ld preload\n");
			break;

		case LONG_DRY_RUN:
			opt_dry_run = 1;
			break;

		case LONG_NO_LIBRARY:
			opt_library = LIBRARY_DISABLE;
			INFO("using LD_LIBRARY_PATH to find library\n");
			break;

		case LONG_LIBRARY:
			opt_library = optarg;
			break;

		case LONG_SHARE:
			opt_share = 1;
			break;

		case -1:
			break;

		default:
			WARNING("unparsed option %08x\n", ret);
			ret = -1;
			break;
		}
	}
	index = optind;

	if (!opt_dry_run && (argc - index) < 1) {
		print_usage();
		exit(EXIT_FAILURE);
	}

	verbose_expose();

	if (opt_library != LIBRARY_DISABLE)
		library_path(opt_library);

	if (opt_mappings)
		setup_mappings(opt_mappings);

	if (opt_preload)
		ldpreload(opt_mappings);

	if (opt_no_reserve)
		setup_environment("HUGETLB_NO_RESERVE", "yes");

	if (opt_share)
		setup_environment("HUGETLB_SHARE", "1");

	if (opt_dry_run)
		exit(EXIT_SUCCESS);

	execvp(argv[index], &argv[index]);
	ERROR("exec failed: %s\n", strerror(errno));
	exit(EXIT_FAILURE);
}