xref: /freebsd/sys/kern/kern_malloc.c (revision 6e0da4f753ed6b5d26395001a6194b4fdea70177)
1 /*-
2  * Copyright (c) 1987, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)kern_malloc.c	8.3 (Berkeley) 1/4/94
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_vm.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kdb.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/malloc.h>
43 #include <sys/mbuf.h>
44 #include <sys/mutex.h>
45 #include <sys/vmmeter.h>
46 #include <sys/proc.h>
47 #include <sys/sysctl.h>
48 #include <sys/time.h>
49 
50 #include <vm/vm.h>
51 #include <vm/pmap.h>
52 #include <vm/vm_param.h>
53 #include <vm/vm_kern.h>
54 #include <vm/vm_extern.h>
55 #include <vm/vm_map.h>
56 #include <vm/vm_page.h>
57 #include <vm/uma.h>
58 #include <vm/uma_int.h>
59 #include <vm/uma_dbg.h>
60 
61 #if defined(INVARIANTS) && defined(__i386__)
62 #include <machine/cpu.h>
63 #endif
64 
65 /*
66  * When realloc() is called, if the new size is sufficiently smaller than
67  * the old size, realloc() will allocate a new, smaller block to avoid
68  * wasting memory. 'Sufficiently smaller' is defined as: newsize <=
69  * oldsize / 2^n, where REALLOC_FRACTION defines the value of 'n'.
70  */
71 #ifndef REALLOC_FRACTION
72 #define	REALLOC_FRACTION	1	/* new block if <= half the size */
73 #endif
74 
75 MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches");
76 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
77 MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers");
78 
79 MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
80 MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery");
81 
82 static void kmeminit(void *);
83 SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, kmeminit, NULL)
84 
85 static MALLOC_DEFINE(M_FREE, "free", "should be on free list");
86 
87 static struct malloc_type *kmemstatistics;
88 static char *kmembase;
89 static char *kmemlimit;
90 
91 #define KMEM_ZSHIFT	4
92 #define KMEM_ZBASE	16
93 #define KMEM_ZMASK	(KMEM_ZBASE - 1)
94 
95 #define KMEM_ZMAX	PAGE_SIZE
96 #define KMEM_ZSIZE	(KMEM_ZMAX >> KMEM_ZSHIFT)
97 static u_int8_t kmemsize[KMEM_ZSIZE + 1];
98 
99 /* These won't be powers of two for long */
100 struct {
101 	int kz_size;
102 	char *kz_name;
103 	uma_zone_t kz_zone;
104 } kmemzones[] = {
105 	{16, "16", NULL},
106 	{32, "32", NULL},
107 	{64, "64", NULL},
108 	{128, "128", NULL},
109 	{256, "256", NULL},
110 	{512, "512", NULL},
111 	{1024, "1024", NULL},
112 	{2048, "2048", NULL},
113 	{4096, "4096", NULL},
114 #if PAGE_SIZE > 4096
115 	{8192, "8192", NULL},
116 #if PAGE_SIZE > 8192
117 	{16384, "16384", NULL},
118 #if PAGE_SIZE > 16384
119 	{32768, "32768", NULL},
120 #if PAGE_SIZE > 32768
121 	{65536, "65536", NULL},
122 #if PAGE_SIZE > 65536
123 #error	"Unsupported PAGE_SIZE"
124 #endif	/* 65536 */
125 #endif	/* 32768 */
126 #endif	/* 16384 */
127 #endif	/* 8192 */
128 #endif	/* 4096 */
129 	{0, NULL},
130 };
131 
132 u_int vm_kmem_size;
133 SYSCTL_UINT(_vm, OID_AUTO, kmem_size, CTLFLAG_RD, &vm_kmem_size, 0,
134     "Size of kernel memory");
135 
136 u_int vm_kmem_size_max;
137 SYSCTL_UINT(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RD, &vm_kmem_size_max, 0,
138     "Maximum size of kernel memory");
139 
140 u_int vm_kmem_size_scale;
141 SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RD, &vm_kmem_size_scale, 0,
142     "Scale factor for kernel memory size");
143 
144 /*
145  * The malloc_mtx protects the kmemstatistics linked list.
146  */
147 
148 struct mtx malloc_mtx;
149 
150 #ifdef MALLOC_PROFILE
151 uint64_t krequests[KMEM_ZSIZE + 1];
152 
153 static int sysctl_kern_mprof(SYSCTL_HANDLER_ARGS);
154 #endif
155 
156 static int sysctl_kern_malloc(SYSCTL_HANDLER_ARGS);
157 
158 /* time_uptime of last malloc(9) failure */
159 static time_t t_malloc_fail;
160 
161 #ifdef MALLOC_MAKE_FAILURES
162 /*
163  * Causes malloc failures every (n) mallocs with M_NOWAIT.  If set to 0,
164  * doesn't cause failures.
165  */
166 SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD, 0,
167     "Kernel malloc debugging options");
168 
169 static int malloc_failure_rate;
170 static int malloc_nowait_count;
171 static int malloc_failure_count;
172 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RW,
173     &malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail");
174 TUNABLE_INT("debug.malloc.failure_rate", &malloc_failure_rate);
175 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD,
176     &malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures");
177 #endif
178 
179 int
180 malloc_last_fail(void)
181 {
182 
183 	return (time_uptime - t_malloc_fail);
184 }
185 
186 /*
187  * Add this to the informational malloc_type bucket.
188  */
189 static void
190 malloc_type_zone_allocated(struct malloc_type *ksp, unsigned long size,
191     int zindx)
192 {
193 	mtx_lock(&ksp->ks_mtx);
194 	ksp->ks_calls++;
195 	if (zindx != -1)
196 		ksp->ks_size |= 1 << zindx;
197 	if (size != 0) {
198 		ksp->ks_memuse += size;
199 		ksp->ks_inuse++;
200 		if (ksp->ks_memuse > ksp->ks_maxused)
201 			ksp->ks_maxused = ksp->ks_memuse;
202 	}
203 	mtx_unlock(&ksp->ks_mtx);
204 }
205 
206 void
207 malloc_type_allocated(struct malloc_type *ksp, unsigned long size)
208 {
209 	malloc_type_zone_allocated(ksp, size, -1);
210 }
211 
212 /*
213  * Remove this allocation from the informational malloc_type bucket.
214  */
215 void
216 malloc_type_freed(struct malloc_type *ksp, unsigned long size)
217 {
218 	mtx_lock(&ksp->ks_mtx);
219 	KASSERT(size <= ksp->ks_memuse,
220 		("malloc(9)/free(9) confusion.\n%s",
221 		 "Probably freeing with wrong type, but maybe not here."));
222 	ksp->ks_memuse -= size;
223 	ksp->ks_inuse--;
224 	mtx_unlock(&ksp->ks_mtx);
225 }
226 
227 /*
228  *	malloc:
229  *
230  *	Allocate a block of memory.
231  *
232  *	If M_NOWAIT is set, this routine will not block and return NULL if
233  *	the allocation fails.
234  */
235 void *
236 malloc(size, type, flags)
237 	unsigned long size;
238 	struct malloc_type *type;
239 	int flags;
240 {
241 	int indx;
242 	caddr_t va;
243 	uma_zone_t zone;
244 	uma_keg_t keg;
245 #ifdef DIAGNOSTIC
246 	unsigned long osize = size;
247 #endif
248 
249 #ifdef INVARIANTS
250 	/*
251 	 * To make sure that WAITOK or NOWAIT is set, but not more than
252 	 * one, and check against the API botches that are common.
253 	 */
254 	indx = flags & (M_WAITOK | M_NOWAIT | M_DONTWAIT | M_TRYWAIT);
255 	if (indx != M_NOWAIT && indx != M_WAITOK) {
256 		static	struct timeval lasterr;
257 		static	int curerr, once;
258 		if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) {
259 			printf("Bad malloc flags: %x\n", indx);
260 			kdb_backtrace();
261 			flags |= M_WAITOK;
262 			once++;
263 		}
264 	}
265 #endif
266 #if 0
267 	if (size == 0)
268 		kdb_enter("zero size malloc");
269 #endif
270 #ifdef MALLOC_MAKE_FAILURES
271 	if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) {
272 		atomic_add_int(&malloc_nowait_count, 1);
273 		if ((malloc_nowait_count % malloc_failure_rate) == 0) {
274 			atomic_add_int(&malloc_failure_count, 1);
275 			t_malloc_fail = time_uptime;
276 			return (NULL);
277 		}
278 	}
279 #endif
280 	if (flags & M_WAITOK)
281 		KASSERT(curthread->td_intr_nesting_level == 0,
282 		   ("malloc(M_WAITOK) in interrupt context"));
283 	if (size <= KMEM_ZMAX) {
284 		if (size & KMEM_ZMASK)
285 			size = (size & ~KMEM_ZMASK) + KMEM_ZBASE;
286 		indx = kmemsize[size >> KMEM_ZSHIFT];
287 		zone = kmemzones[indx].kz_zone;
288 		keg = zone->uz_keg;
289 #ifdef MALLOC_PROFILE
290 		krequests[size >> KMEM_ZSHIFT]++;
291 #endif
292 		va = uma_zalloc(zone, flags);
293 		if (va != NULL)
294 			size = keg->uk_size;
295 		malloc_type_zone_allocated(type, va == NULL ? 0 : size, indx);
296 	} else {
297 		size = roundup(size, PAGE_SIZE);
298 		zone = NULL;
299 		keg = NULL;
300 		va = uma_large_malloc(size, flags);
301 		malloc_type_allocated(type, va == NULL ? 0 : size);
302 	}
303 	if (flags & M_WAITOK)
304 		KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL"));
305 	else if (va == NULL)
306 		t_malloc_fail = time_uptime;
307 #ifdef DIAGNOSTIC
308 	if (va != NULL && !(flags & M_ZERO)) {
309 		memset(va, 0x70, osize);
310 	}
311 #endif
312 	return ((void *) va);
313 }
314 
315 /*
316  *	free:
317  *
318  *	Free a block of memory allocated by malloc.
319  *
320  *	This routine may not block.
321  */
322 void
323 free(addr, type)
324 	void *addr;
325 	struct malloc_type *type;
326 {
327 	uma_slab_t slab;
328 	u_long size;
329 
330 	/* free(NULL, ...) does nothing */
331 	if (addr == NULL)
332 		return;
333 
334 	KASSERT(type->ks_memuse > 0,
335 		("malloc(9)/free(9) confusion.\n%s",
336 		 "Probably freeing with wrong type, but maybe not here."));
337 	size = 0;
338 
339 	slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK));
340 
341 	if (slab == NULL)
342 		panic("free: address %p(%p) has not been allocated.\n",
343 		    addr, (void *)((u_long)addr & (~UMA_SLAB_MASK)));
344 
345 
346 	if (!(slab->us_flags & UMA_SLAB_MALLOC)) {
347 #ifdef INVARIANTS
348 		struct malloc_type **mtp = addr;
349 #endif
350 		size = slab->us_keg->uk_size;
351 #ifdef INVARIANTS
352 		/*
353 		 * Cache a pointer to the malloc_type that most recently freed
354 		 * this memory here.  This way we know who is most likely to
355 		 * have stepped on it later.
356 		 *
357 		 * This code assumes that size is a multiple of 8 bytes for
358 		 * 64 bit machines
359 		 */
360 		mtp = (struct malloc_type **)
361 		    ((unsigned long)mtp & ~UMA_ALIGN_PTR);
362 		mtp += (size - sizeof(struct malloc_type *)) /
363 		    sizeof(struct malloc_type *);
364 		*mtp = type;
365 #endif
366 		uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab);
367 	} else {
368 		size = slab->us_size;
369 		uma_large_free(slab);
370 	}
371 	malloc_type_freed(type, size);
372 }
373 
374 /*
375  *	realloc: change the size of a memory block
376  */
377 void *
378 realloc(addr, size, type, flags)
379 	void *addr;
380 	unsigned long size;
381 	struct malloc_type *type;
382 	int flags;
383 {
384 	uma_slab_t slab;
385 	unsigned long alloc;
386 	void *newaddr;
387 
388 	/* realloc(NULL, ...) is equivalent to malloc(...) */
389 	if (addr == NULL)
390 		return (malloc(size, type, flags));
391 
392 	slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK));
393 
394 	/* Sanity check */
395 	KASSERT(slab != NULL,
396 	    ("realloc: address %p out of range", (void *)addr));
397 
398 	/* Get the size of the original block */
399 	if (slab->us_keg)
400 		alloc = slab->us_keg->uk_size;
401 	else
402 		alloc = slab->us_size;
403 
404 	/* Reuse the original block if appropriate */
405 	if (size <= alloc
406 	    && (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE))
407 		return (addr);
408 
409 	/* Allocate a new, bigger (or smaller) block */
410 	if ((newaddr = malloc(size, type, flags)) == NULL)
411 		return (NULL);
412 
413 	/* Copy over original contents */
414 	bcopy(addr, newaddr, min(size, alloc));
415 	free(addr, type);
416 	return (newaddr);
417 }
418 
419 /*
420  *	reallocf: same as realloc() but free memory on failure.
421  */
422 void *
423 reallocf(addr, size, type, flags)
424 	void *addr;
425 	unsigned long size;
426 	struct malloc_type *type;
427 	int flags;
428 {
429 	void *mem;
430 
431 	if ((mem = realloc(addr, size, type, flags)) == NULL)
432 		free(addr, type);
433 	return (mem);
434 }
435 
436 /*
437  * Initialize the kernel memory allocator
438  */
439 /* ARGSUSED*/
440 static void
441 kmeminit(dummy)
442 	void *dummy;
443 {
444 	u_int8_t indx;
445 	u_long mem_size;
446 	int i;
447 
448 	mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF);
449 
450 	/*
451 	 * Try to auto-tune the kernel memory size, so that it is
452 	 * more applicable for a wider range of machine sizes.
453 	 * On an X86, a VM_KMEM_SIZE_SCALE value of 4 is good, while
454 	 * a VM_KMEM_SIZE of 12MB is a fair compromise.  The
455 	 * VM_KMEM_SIZE_MAX is dependent on the maximum KVA space
456 	 * available, and on an X86 with a total KVA space of 256MB,
457 	 * try to keep VM_KMEM_SIZE_MAX at 80MB or below.
458 	 *
459 	 * Note that the kmem_map is also used by the zone allocator,
460 	 * so make sure that there is enough space.
461 	 */
462 	vm_kmem_size = VM_KMEM_SIZE + nmbclusters * PAGE_SIZE;
463 	mem_size = cnt.v_page_count;
464 
465 #if defined(VM_KMEM_SIZE_SCALE)
466 	vm_kmem_size_scale = VM_KMEM_SIZE_SCALE;
467 #endif
468 	TUNABLE_INT_FETCH("vm.kmem_size_scale", &vm_kmem_size_scale);
469 	if (vm_kmem_size_scale > 0 &&
470 	    (mem_size / vm_kmem_size_scale) > (vm_kmem_size / PAGE_SIZE))
471 		vm_kmem_size = (mem_size / vm_kmem_size_scale) * PAGE_SIZE;
472 
473 #if defined(VM_KMEM_SIZE_MAX)
474 	vm_kmem_size_max = VM_KMEM_SIZE_MAX;
475 #endif
476 	TUNABLE_INT_FETCH("vm.kmem_size_max", &vm_kmem_size_max);
477 	if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max)
478 		vm_kmem_size = vm_kmem_size_max;
479 
480 	/* Allow final override from the kernel environment */
481 #ifndef BURN_BRIDGES
482 	if (TUNABLE_INT_FETCH("kern.vm.kmem.size", &vm_kmem_size) != 0)
483 		printf("kern.vm.kmem.size is now called vm.kmem_size!\n");
484 #endif
485 	TUNABLE_INT_FETCH("vm.kmem_size", &vm_kmem_size);
486 
487 	/*
488 	 * Limit kmem virtual size to twice the physical memory.
489 	 * This allows for kmem map sparseness, but limits the size
490 	 * to something sane. Be careful to not overflow the 32bit
491 	 * ints while doing the check.
492 	 */
493 	if (((vm_kmem_size / 2) / PAGE_SIZE) > cnt.v_page_count)
494 		vm_kmem_size = 2 * cnt.v_page_count * PAGE_SIZE;
495 
496 	/*
497 	 * Tune settings based on the kernel map's size at this time.
498 	 */
499 	init_param3(vm_kmem_size / PAGE_SIZE);
500 
501 	kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase,
502 		(vm_offset_t *)&kmemlimit, vm_kmem_size);
503 	kmem_map->system_map = 1;
504 
505 	uma_startup2();
506 
507 	for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) {
508 		int size = kmemzones[indx].kz_size;
509 		char *name = kmemzones[indx].kz_name;
510 
511 		kmemzones[indx].kz_zone = uma_zcreate(name, size,
512 #ifdef INVARIANTS
513 		    mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini,
514 #else
515 		    NULL, NULL, NULL, NULL,
516 #endif
517 		    UMA_ALIGN_PTR, UMA_ZONE_MALLOC);
518 
519 		for (;i <= size; i+= KMEM_ZBASE)
520 			kmemsize[i >> KMEM_ZSHIFT] = indx;
521 
522 	}
523 }
524 
525 void
526 malloc_init(data)
527 	void *data;
528 {
529 	struct malloc_type *type = (struct malloc_type *)data;
530 
531 	mtx_lock(&malloc_mtx);
532 	if (type->ks_magic != M_MAGIC)
533 		panic("malloc type lacks magic");
534 
535 	if (cnt.v_page_count == 0)
536 		panic("malloc_init not allowed before vm init");
537 
538 	if (type->ks_next != NULL)
539 		return;
540 
541 	type->ks_next = kmemstatistics;
542 	kmemstatistics = type;
543 	mtx_init(&type->ks_mtx, type->ks_shortdesc, "Malloc Stats", MTX_DEF);
544 	mtx_unlock(&malloc_mtx);
545 }
546 
547 void
548 malloc_uninit(data)
549 	void *data;
550 {
551 	struct malloc_type *type = (struct malloc_type *)data;
552 	struct malloc_type *t;
553 
554 	mtx_lock(&malloc_mtx);
555 	mtx_lock(&type->ks_mtx);
556 	if (type->ks_magic != M_MAGIC)
557 		panic("malloc type lacks magic");
558 
559 	if (cnt.v_page_count == 0)
560 		panic("malloc_uninit not allowed before vm init");
561 
562 	if (type == kmemstatistics)
563 		kmemstatistics = type->ks_next;
564 	else {
565 		for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) {
566 			if (t->ks_next == type) {
567 				t->ks_next = type->ks_next;
568 				break;
569 			}
570 		}
571 	}
572 	type->ks_next = NULL;
573 	mtx_destroy(&type->ks_mtx);
574 	mtx_unlock(&malloc_mtx);
575 }
576 
577 static int
578 sysctl_kern_malloc(SYSCTL_HANDLER_ARGS)
579 {
580 	struct malloc_type *type;
581 	int linesize = 128;
582 	int curline;
583 	int bufsize;
584 	int first;
585 	int error;
586 	char *buf;
587 	char *p;
588 	int cnt;
589 	int len;
590 	int i;
591 
592 	cnt = 0;
593 
594 	mtx_lock(&malloc_mtx);
595 	for (type = kmemstatistics; type != NULL; type = type->ks_next)
596 		cnt++;
597 
598 	mtx_unlock(&malloc_mtx);
599 	bufsize = linesize * (cnt + 1);
600 	p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO);
601 	mtx_lock(&malloc_mtx);
602 
603 	len = snprintf(p, linesize,
604 	    "\n        Type  InUse MemUse HighUse Requests  Size(s)\n");
605 	p += len;
606 
607 	for (type = kmemstatistics; cnt != 0 && type != NULL;
608 	    type = type->ks_next, cnt--) {
609 		if (type->ks_calls == 0)
610 			continue;
611 
612 		curline = linesize - 2;	/* Leave room for the \n */
613 		len = snprintf(p, curline, "%13s%6lu%6luK%7luK%9llu",
614 			type->ks_shortdesc,
615 			type->ks_inuse,
616 			(type->ks_memuse + 1023) / 1024,
617 			(type->ks_maxused + 1023) / 1024,
618 			(long long unsigned)type->ks_calls);
619 		curline -= len;
620 		p += len;
621 
622 		first = 1;
623 		for (i = 0; i < sizeof(kmemzones) / sizeof(kmemzones[0]) - 1;
624 		    i++) {
625 			if (type->ks_size & (1 << i)) {
626 				if (first)
627 					len = snprintf(p, curline, "  ");
628 				else
629 					len = snprintf(p, curline, ",");
630 				curline -= len;
631 				p += len;
632 
633 				len = snprintf(p, curline,
634 				    "%s", kmemzones[i].kz_name);
635 				curline -= len;
636 				p += len;
637 
638 				first = 0;
639 			}
640 		}
641 
642 		len = snprintf(p, 2, "\n");
643 		p += len;
644 	}
645 
646 	mtx_unlock(&malloc_mtx);
647 	error = SYSCTL_OUT(req, buf, p - buf);
648 
649 	free(buf, M_TEMP);
650 	return (error);
651 }
652 
653 SYSCTL_OID(_kern, OID_AUTO, malloc, CTLTYPE_STRING|CTLFLAG_RD,
654     NULL, 0, sysctl_kern_malloc, "A", "Malloc Stats");
655 
656 #ifdef MALLOC_PROFILE
657 
658 static int
659 sysctl_kern_mprof(SYSCTL_HANDLER_ARGS)
660 {
661 	int linesize = 64;
662 	uint64_t count;
663 	uint64_t waste;
664 	uint64_t mem;
665 	int bufsize;
666 	int error;
667 	char *buf;
668 	int rsize;
669 	int size;
670 	char *p;
671 	int len;
672 	int i;
673 
674 	bufsize = linesize * (KMEM_ZSIZE + 1);
675 	bufsize += 128; 	/* For the stats line */
676 	bufsize += 128; 	/* For the banner line */
677 	waste = 0;
678 	mem = 0;
679 
680 	p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO);
681 	len = snprintf(p, bufsize,
682 	    "\n  Size                    Requests  Real Size\n");
683 	bufsize -= len;
684 	p += len;
685 
686 	for (i = 0; i < KMEM_ZSIZE; i++) {
687 		size = i << KMEM_ZSHIFT;
688 		rsize = kmemzones[kmemsize[i]].kz_size;
689 		count = (long long unsigned)krequests[i];
690 
691 		len = snprintf(p, bufsize, "%6d%28llu%11d\n",
692 		    size, (unsigned long long)count, rsize);
693 		bufsize -= len;
694 		p += len;
695 
696 		if ((rsize * count) > (size * count))
697 			waste += (rsize * count) - (size * count);
698 		mem += (rsize * count);
699 	}
700 
701 	len = snprintf(p, bufsize,
702 	    "\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n",
703 	    (unsigned long long)mem, (unsigned long long)waste);
704 	p += len;
705 
706 	error = SYSCTL_OUT(req, buf, p - buf);
707 
708 	free(buf, M_TEMP);
709 	return (error);
710 }
711 
712 SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD,
713     NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling");
714 #endif /* MALLOC_PROFILE */
715