xref: /freebsd/lib/libmemstat/memstat_uma.c (revision e17f5b1d307b7b8910d67883e57a9604305906d5) 
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2005-2006 Robert N. M. Watson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #include <sys/param.h>
32 #include <sys/counter.h>
33 #include <sys/cpuset.h>
34 #include <sys/sysctl.h>
35 
36 #include <vm/uma.h>
37 #include <vm/uma_int.h>
38 
39 #include <err.h>
40 #include <errno.h>
41 #include <kvm.h>
42 #include <nlist.h>
43 #include <stddef.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include "memstat.h"
50 #include "memstat_internal.h"
51 
52 static struct nlist namelist[] = {
53 #define	X_UMA_KEGS	0
54 	{ .n_name = "_uma_kegs" },
55 #define	X_MP_MAXID	1
56 	{ .n_name = "_mp_maxid" },
57 #define	X_ALL_CPUS	2
58 	{ .n_name = "_all_cpus" },
59 #define	X_VM_NDOMAINS	3
60 	{ .n_name = "_vm_ndomains" },
61 	{ .n_name = "" },
62 };
63 
64 /*
65  * Extract uma(9) statistics from the running kernel, and store all memory
66  * type information in the passed list.  For each type, check the list for an
67  * existing entry with the right name/allocator -- if present, update that
68  * entry.  Otherwise, add a new entry.  On error, the entire list will be
69  * cleared, as entries will be in an inconsistent state.
70  *
71  * To reduce the level of work for a list that starts empty, we keep around a
72  * hint as to whether it was empty when we began, so we can avoid searching
73  * the list for entries to update.  Updates are O(n^2) due to searching for
74  * each entry before adding it.
75  */
76 int
77 memstat_sysctl_uma(struct memory_type_list *list, int flags)
78 {
79 	struct uma_stream_header *ushp;
80 	struct uma_type_header *uthp;
81 	struct uma_percpu_stat *upsp;
82 	struct memory_type *mtp;
83 	int count, hint_dontsearch, i, j, maxcpus, maxid;
84 	char *buffer, *p;
85 	size_t size;
86 
87 	hint_dontsearch = LIST_EMPTY(&list->mtl_list);
88 
89 	/*
90 	 * Query the number of CPUs, number of malloc types so that we can
91 	 * guess an initial buffer size.  We loop until we succeed or really
92 	 * fail.  Note that the value of maxcpus we query using sysctl is not
93 	 * the version we use when processing the real data -- that is read
94 	 * from the header.
95 	 */
96 retry:
97 	size = sizeof(maxid);
98 	if (sysctlbyname("kern.smp.maxid", &maxid, &size, NULL, 0) < 0) {
99 		if (errno == EACCES || errno == EPERM)
100 			list->mtl_error = MEMSTAT_ERROR_PERMISSION;
101 		else
102 			list->mtl_error = MEMSTAT_ERROR_DATAERROR;
103 		return (-1);
104 	}
105 	if (size != sizeof(maxid)) {
106 		list->mtl_error = MEMSTAT_ERROR_DATAERROR;
107 		return (-1);
108 	}
109 
110 	size = sizeof(count);
111 	if (sysctlbyname("vm.zone_count", &count, &size, NULL, 0) < 0) {
112 		if (errno == EACCES || errno == EPERM)
113 			list->mtl_error = MEMSTAT_ERROR_PERMISSION;
114 		else
115 			list->mtl_error = MEMSTAT_ERROR_VERSION;
116 		return (-1);
117 	}
118 	if (size != sizeof(count)) {
119 		list->mtl_error = MEMSTAT_ERROR_DATAERROR;
120 		return (-1);
121 	}
122 
123 	size = sizeof(*uthp) + count * (sizeof(*uthp) + sizeof(*upsp) *
124 	    (maxid + 1));
125 
126 	buffer = malloc(size);
127 	if (buffer == NULL) {
128 		list->mtl_error = MEMSTAT_ERROR_NOMEMORY;
129 		return (-1);
130 	}
131 
132 	if (sysctlbyname("vm.zone_stats", buffer, &size, NULL, 0) < 0) {
133 		/*
134 		 * XXXRW: ENOMEM is an ambiguous return, we should bound the
135 		 * number of loops, perhaps.
136 		 */
137 		if (errno == ENOMEM) {
138 			free(buffer);
139 			goto retry;
140 		}
141 		if (errno == EACCES || errno == EPERM)
142 			list->mtl_error = MEMSTAT_ERROR_PERMISSION;
143 		else
144 			list->mtl_error = MEMSTAT_ERROR_VERSION;
145 		free(buffer);
146 		return (-1);
147 	}
148 
149 	if (size == 0) {
150 		free(buffer);
151 		return (0);
152 	}
153 
154 	if (size < sizeof(*ushp)) {
155 		list->mtl_error = MEMSTAT_ERROR_VERSION;
156 		free(buffer);
157 		return (-1);
158 	}
159 	p = buffer;
160 	ushp = (struct uma_stream_header *)p;
161 	p += sizeof(*ushp);
162 
163 	if (ushp->ush_version != UMA_STREAM_VERSION) {
164 		list->mtl_error = MEMSTAT_ERROR_VERSION;
165 		free(buffer);
166 		return (-1);
167 	}
168 
169 	/*
170 	 * For the remainder of this function, we are quite trusting about
171 	 * the layout of structures and sizes, since we've determined we have
172 	 * a matching version and acceptable CPU count.
173 	 */
174 	maxcpus = ushp->ush_maxcpus;
175 	count = ushp->ush_count;
176 	for (i = 0; i < count; i++) {
177 		uthp = (struct uma_type_header *)p;
178 		p += sizeof(*uthp);
179 
180 		if (hint_dontsearch == 0) {
181 			mtp = memstat_mtl_find(list, ALLOCATOR_UMA,
182 			    uthp->uth_name);
183 		} else
184 			mtp = NULL;
185 		if (mtp == NULL)
186 			mtp = _memstat_mt_allocate(list, ALLOCATOR_UMA,
187 			    uthp->uth_name, maxid + 1);
188 		if (mtp == NULL) {
189 			_memstat_mtl_empty(list);
190 			free(buffer);
191 			list->mtl_error = MEMSTAT_ERROR_NOMEMORY;
192 			return (-1);
193 		}
194 
195 		/*
196 		 * Reset the statistics on a current node.
197 		 */
198 		_memstat_mt_reset_stats(mtp, maxid + 1);
199 
200 		mtp->mt_numallocs = uthp->uth_allocs;
201 		mtp->mt_numfrees = uthp->uth_frees;
202 		mtp->mt_failures = uthp->uth_fails;
203 		mtp->mt_sleeps = uthp->uth_sleeps;
204 		mtp->mt_xdomain = uthp->uth_xdomain;
205 
206 		for (j = 0; j < maxcpus; j++) {
207 			upsp = (struct uma_percpu_stat *)p;
208 			p += sizeof(*upsp);
209 
210 			mtp->mt_percpu_cache[j].mtp_free =
211 			    upsp->ups_cache_free;
212 			mtp->mt_free += upsp->ups_cache_free;
213 			mtp->mt_numallocs += upsp->ups_allocs;
214 			mtp->mt_numfrees += upsp->ups_frees;
215 		}
216 
217 		/*
218 		 * Values for uth_allocs and uth_frees frees are snap.
219 		 * It may happen that kernel reports that number of frees
220 		 * is greater than number of allocs. See counter(9) for
221 		 * details.
222 		 */
223 		if (mtp->mt_numallocs < mtp->mt_numfrees)
224 			mtp->mt_numallocs = mtp->mt_numfrees;
225 
226 		mtp->mt_size = uthp->uth_size;
227 		mtp->mt_rsize = uthp->uth_rsize;
228 		mtp->mt_memalloced = mtp->mt_numallocs * uthp->uth_size;
229 		mtp->mt_memfreed = mtp->mt_numfrees * uthp->uth_size;
230 		mtp->mt_bytes = mtp->mt_memalloced - mtp->mt_memfreed;
231 		mtp->mt_countlimit = uthp->uth_limit;
232 		mtp->mt_byteslimit = uthp->uth_limit * uthp->uth_size;
233 
234 		mtp->mt_count = mtp->mt_numallocs - mtp->mt_numfrees;
235 		mtp->mt_zonefree = uthp->uth_zone_free;
236 
237 		/*
238 		 * UMA secondary zones share a keg with the primary zone.  To
239 		 * avoid double-reporting of free items, report keg free
240 		 * items only in the primary zone.
241 		 */
242 		if (!(uthp->uth_zone_flags & UTH_ZONE_SECONDARY)) {
243 			mtp->mt_kegfree = uthp->uth_keg_free;
244 			mtp->mt_free += mtp->mt_kegfree;
245 		}
246 		mtp->mt_free += mtp->mt_zonefree;
247 	}
248 
249 	free(buffer);
250 
251 	return (0);
252 }
253 
254 static int
255 kread(kvm_t *kvm, void *kvm_pointer, void *address, size_t size,
256     size_t offset)
257 {
258 	ssize_t ret;
259 
260 	ret = kvm_read(kvm, (unsigned long)kvm_pointer + offset, address,
261 	    size);
262 	if (ret < 0)
263 		return (MEMSTAT_ERROR_KVM);
264 	if ((size_t)ret != size)
265 		return (MEMSTAT_ERROR_KVM_SHORTREAD);
266 	return (0);
267 }
268 
269 static int
270 kread_string(kvm_t *kvm, const void *kvm_pointer, char *buffer, int buflen)
271 {
272 	ssize_t ret;
273 	int i;
274 
275 	for (i = 0; i < buflen; i++) {
276 		ret = kvm_read(kvm, (unsigned long)kvm_pointer + i,
277 		    &(buffer[i]), sizeof(char));
278 		if (ret < 0)
279 			return (MEMSTAT_ERROR_KVM);
280 		if ((size_t)ret != sizeof(char))
281 			return (MEMSTAT_ERROR_KVM_SHORTREAD);
282 		if (buffer[i] == '\0')
283 			return (0);
284 	}
285 	/* Truncate. */
286 	buffer[i-1] = '\0';
287 	return (0);
288 }
289 
290 static int
291 kread_symbol(kvm_t *kvm, int index, void *address, size_t size,
292     size_t offset)
293 {
294 	ssize_t ret;
295 
296 	ret = kvm_read(kvm, namelist[index].n_value + offset, address, size);
297 	if (ret < 0)
298 		return (MEMSTAT_ERROR_KVM);
299 	if ((size_t)ret != size)
300 		return (MEMSTAT_ERROR_KVM_SHORTREAD);
301 	return (0);
302 }
303 
304 /*
305  * memstat_kvm_uma() is similar to memstat_sysctl_uma(), only it extracts
306  * UMA(9) statistics from a kernel core/memory file.
307  */
308 int
309 memstat_kvm_uma(struct memory_type_list *list, void *kvm_handle)
310 {
311 	LIST_HEAD(, uma_keg) uma_kegs;
312 	struct memory_type *mtp;
313 	struct uma_zone_domain uzd;
314 	struct uma_domain ukd;
315 	struct uma_bucket *ubp, ub;
316 	struct uma_cache *ucp, *ucp_array;
317 	struct uma_zone *uzp, uz;
318 	struct uma_keg *kzp, kz;
319 	uint64_t kegfree;
320 	int hint_dontsearch, i, mp_maxid, ndomains, ret;
321 	char name[MEMTYPE_MAXNAME];
322 	cpuset_t all_cpus;
323 	long cpusetsize;
324 	kvm_t *kvm;
325 
326 	kvm = (kvm_t *)kvm_handle;
327 	hint_dontsearch = LIST_EMPTY(&list->mtl_list);
328 	if (kvm_nlist(kvm, namelist) != 0) {
329 		list->mtl_error = MEMSTAT_ERROR_KVM;
330 		return (-1);
331 	}
332 	if (namelist[X_UMA_KEGS].n_type == 0 ||
333 	    namelist[X_UMA_KEGS].n_value == 0) {
334 		list->mtl_error = MEMSTAT_ERROR_KVM_NOSYMBOL;
335 		return (-1);
336 	}
337 	ret = kread_symbol(kvm, X_MP_MAXID, &mp_maxid, sizeof(mp_maxid), 0);
338 	if (ret != 0) {
339 		list->mtl_error = ret;
340 		return (-1);
341 	}
342 	ret = kread_symbol(kvm, X_VM_NDOMAINS, &ndomains,
343 	    sizeof(ndomains), 0);
344 	if (ret != 0) {
345 		list->mtl_error = ret;
346 		return (-1);
347 	}
348 	ret = kread_symbol(kvm, X_UMA_KEGS, &uma_kegs, sizeof(uma_kegs), 0);
349 	if (ret != 0) {
350 		list->mtl_error = ret;
351 		return (-1);
352 	}
353 	cpusetsize = sysconf(_SC_CPUSET_SIZE);
354 	if (cpusetsize == -1 || (u_long)cpusetsize > sizeof(cpuset_t)) {
355 		list->mtl_error = MEMSTAT_ERROR_KVM_NOSYMBOL;
356 		return (-1);
357 	}
358 	CPU_ZERO(&all_cpus);
359 	ret = kread_symbol(kvm, X_ALL_CPUS, &all_cpus, cpusetsize, 0);
360 	if (ret != 0) {
361 		list->mtl_error = ret;
362 		return (-1);
363 	}
364 	ucp_array = malloc(sizeof(struct uma_cache) * (mp_maxid + 1));
365 	if (ucp_array == NULL) {
366 		list->mtl_error = MEMSTAT_ERROR_NOMEMORY;
367 		return (-1);
368 	}
369 	for (kzp = LIST_FIRST(&uma_kegs); kzp != NULL; kzp =
370 	    LIST_NEXT(&kz, uk_link)) {
371 		ret = kread(kvm, kzp, &kz, sizeof(kz), 0);
372 		if (ret != 0) {
373 			free(ucp_array);
374 			_memstat_mtl_empty(list);
375 			list->mtl_error = ret;
376 			return (-1);
377 		}
378 		for (uzp = LIST_FIRST(&kz.uk_zones); uzp != NULL; uzp =
379 		    LIST_NEXT(&uz, uz_link)) {
380 			ret = kread(kvm, uzp, &uz, sizeof(uz), 0);
381 			if (ret != 0) {
382 				free(ucp_array);
383 				_memstat_mtl_empty(list);
384 				list->mtl_error = ret;
385 				return (-1);
386 			}
387 			ret = kread(kvm, uzp, ucp_array,
388 			    sizeof(struct uma_cache) * (mp_maxid + 1),
389 			    offsetof(struct uma_zone, uz_cpu[0]));
390 			if (ret != 0) {
391 				free(ucp_array);
392 				_memstat_mtl_empty(list);
393 				list->mtl_error = ret;
394 				return (-1);
395 			}
396 			ret = kread_string(kvm, uz.uz_name, name,
397 			    MEMTYPE_MAXNAME);
398 			if (ret != 0) {
399 				free(ucp_array);
400 				_memstat_mtl_empty(list);
401 				list->mtl_error = ret;
402 				return (-1);
403 			}
404 			if (hint_dontsearch == 0) {
405 				mtp = memstat_mtl_find(list, ALLOCATOR_UMA,
406 				    name);
407 			} else
408 				mtp = NULL;
409 			if (mtp == NULL)
410 				mtp = _memstat_mt_allocate(list, ALLOCATOR_UMA,
411 				    name, mp_maxid + 1);
412 			if (mtp == NULL) {
413 				free(ucp_array);
414 				_memstat_mtl_empty(list);
415 				list->mtl_error = MEMSTAT_ERROR_NOMEMORY;
416 				return (-1);
417 			}
418 			/*
419 			 * Reset the statistics on a current node.
420 			 */
421 			_memstat_mt_reset_stats(mtp, mp_maxid + 1);
422 			mtp->mt_numallocs = kvm_counter_u64_fetch(kvm,
423 			    (unsigned long )uz.uz_allocs);
424 			mtp->mt_numfrees = kvm_counter_u64_fetch(kvm,
425 			    (unsigned long )uz.uz_frees);
426 			mtp->mt_failures = kvm_counter_u64_fetch(kvm,
427 			    (unsigned long )uz.uz_fails);
428 			mtp->mt_xdomain = kvm_counter_u64_fetch(kvm,
429 			    (unsigned long )uz.uz_xdomain);
430 			mtp->mt_sleeps = uz.uz_sleeps;
431 			/* See comment above in memstat_sysctl_uma(). */
432 			if (mtp->mt_numallocs < mtp->mt_numfrees)
433 				mtp->mt_numallocs = mtp->mt_numfrees;
434 
435 			if (kz.uk_flags & UMA_ZFLAG_INTERNAL)
436 				goto skip_percpu;
437 			for (i = 0; i < mp_maxid + 1; i++) {
438 				if (!CPU_ISSET(i, &all_cpus))
439 					continue;
440 				ucp = &ucp_array[i];
441 				mtp->mt_numallocs += ucp->uc_allocs;
442 				mtp->mt_numfrees += ucp->uc_frees;
443 
444 				mtp->mt_free += ucp->uc_allocbucket.ucb_cnt;
445 				mtp->mt_free += ucp->uc_freebucket.ucb_cnt;
446 				mtp->mt_free += ucp->uc_crossbucket.ucb_cnt;
447 			}
448 skip_percpu:
449 			mtp->mt_size = kz.uk_size;
450 			mtp->mt_rsize = kz.uk_rsize;
451 			mtp->mt_memalloced = mtp->mt_numallocs * mtp->mt_size;
452 			mtp->mt_memfreed = mtp->mt_numfrees * mtp->mt_size;
453 			mtp->mt_bytes = mtp->mt_memalloced - mtp->mt_memfreed;
454 			mtp->mt_countlimit = uz.uz_max_items;
455 			mtp->mt_byteslimit = mtp->mt_countlimit * mtp->mt_size;
456 			mtp->mt_count = mtp->mt_numallocs - mtp->mt_numfrees;
457 			for (i = 0; i < ndomains; i++) {
458 				ret = kread(kvm,
459 				    &uz.uz_cpu[mp_maxid + 1] + i * sizeof(uzd),
460 				    &uzd, sizeof(uzd), 0);
461 				if (ret != 0)
462 					continue;
463 				for (ubp =
464 				    STAILQ_FIRST(&uzd.uzd_buckets);
465 				    ubp != NULL;
466 				    ubp = STAILQ_NEXT(&ub, ub_link)) {
467 					ret = kread(kvm, ubp, &ub,
468 					   sizeof(ub), 0);
469 					if (ret != 0)
470 						continue;
471 					mtp->mt_zonefree += ub.ub_cnt;
472 				}
473 			}
474 			if (!((kz.uk_flags & UMA_ZONE_SECONDARY) &&
475 			    LIST_FIRST(&kz.uk_zones) != uzp)) {
476 				kegfree = 0;
477 				for (i = 0; i < ndomains; i++) {
478 					ret = kread(kvm, &kzp->uk_domain[i],
479 					    &ukd, sizeof(ukd), 0);
480 					if (ret != 0)
481 						kegfree += ukd.ud_free_items;
482 				}
483 				mtp->mt_kegfree = kegfree;
484 				mtp->mt_free += mtp->mt_kegfree;
485 			}
486 			mtp->mt_free += mtp->mt_zonefree;
487 		}
488 	}
489 	free(ucp_array);
490 	return (0);
491 }
492