xref: /freebsd/sys/kern/kern_malloc.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
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 /*
137  * The malloc_mtx protects the kmemstatistics linked list.
138  */
139 
140 struct mtx malloc_mtx;
141 
142 #ifdef MALLOC_PROFILE
143 uint64_t krequests[KMEM_ZSIZE + 1];
144 
145 static int sysctl_kern_mprof(SYSCTL_HANDLER_ARGS);
146 #endif
147 
148 static int sysctl_kern_malloc(SYSCTL_HANDLER_ARGS);
149 
150 /* time_uptime of last malloc(9) failure */
151 static time_t t_malloc_fail;
152 
153 #ifdef MALLOC_MAKE_FAILURES
154 /*
155  * Causes malloc failures every (n) mallocs with M_NOWAIT.  If set to 0,
156  * doesn't cause failures.
157  */
158 SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD, 0,
159     "Kernel malloc debugging options");
160 
161 static int malloc_failure_rate;
162 static int malloc_nowait_count;
163 static int malloc_failure_count;
164 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RW,
165     &malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail");
166 TUNABLE_INT("debug.malloc.failure_rate", &malloc_failure_rate);
167 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD,
168     &malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures");
169 #endif
170 
171 int
172 malloc_last_fail(void)
173 {
174 
175 	return (time_uptime - t_malloc_fail);
176 }
177 
178 /*
179  * Add this to the informational malloc_type bucket.
180  */
181 static void
182 malloc_type_zone_allocated(struct malloc_type *ksp, unsigned long size,
183     int zindx)
184 {
185 	mtx_lock(&ksp->ks_mtx);
186 	ksp->ks_calls++;
187 	if (zindx != -1)
188 		ksp->ks_size |= 1 << zindx;
189 	if (size != 0) {
190 		ksp->ks_memuse += size;
191 		ksp->ks_inuse++;
192 		if (ksp->ks_memuse > ksp->ks_maxused)
193 			ksp->ks_maxused = ksp->ks_memuse;
194 	}
195 	mtx_unlock(&ksp->ks_mtx);
196 }
197 
198 void
199 malloc_type_allocated(struct malloc_type *ksp, unsigned long size)
200 {
201 	malloc_type_zone_allocated(ksp, size, -1);
202 }
203 
204 /*
205  * Remove this allocation from the informational malloc_type bucket.
206  */
207 void
208 malloc_type_freed(struct malloc_type *ksp, unsigned long size)
209 {
210 	mtx_lock(&ksp->ks_mtx);
211 	KASSERT(size <= ksp->ks_memuse,
212 		("malloc(9)/free(9) confusion.\n%s",
213 		 "Probably freeing with wrong type, but maybe not here."));
214 	ksp->ks_memuse -= size;
215 	ksp->ks_inuse--;
216 	mtx_unlock(&ksp->ks_mtx);
217 }
218 
219 /*
220  *	malloc:
221  *
222  *	Allocate a block of memory.
223  *
224  *	If M_NOWAIT is set, this routine will not block and return NULL if
225  *	the allocation fails.
226  */
227 void *
228 malloc(size, type, flags)
229 	unsigned long size;
230 	struct malloc_type *type;
231 	int flags;
232 {
233 	int indx;
234 	caddr_t va;
235 	uma_zone_t zone;
236 	uma_keg_t keg;
237 #ifdef DIAGNOSTIC
238 	unsigned long osize = size;
239 #endif
240 
241 #ifdef INVARIANTS
242 	/*
243 	 * To make sure that WAITOK or NOWAIT is set, but not more than
244 	 * one, and check against the API botches that are common.
245 	 */
246 	indx = flags & (M_WAITOK | M_NOWAIT | M_DONTWAIT | M_TRYWAIT);
247 	if (indx != M_NOWAIT && indx != M_WAITOK) {
248 		static	struct timeval lasterr;
249 		static	int curerr, once;
250 		if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) {
251 			printf("Bad malloc flags: %x\n", indx);
252 			kdb_backtrace();
253 			flags |= M_WAITOK;
254 			once++;
255 		}
256 	}
257 #endif
258 #if 0
259 	if (size == 0)
260 		kdb_enter("zero size malloc");
261 #endif
262 #ifdef MALLOC_MAKE_FAILURES
263 	if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) {
264 		atomic_add_int(&malloc_nowait_count, 1);
265 		if ((malloc_nowait_count % malloc_failure_rate) == 0) {
266 			atomic_add_int(&malloc_failure_count, 1);
267 			t_malloc_fail = time_uptime;
268 			return (NULL);
269 		}
270 	}
271 #endif
272 	if (flags & M_WAITOK)
273 		KASSERT(curthread->td_intr_nesting_level == 0,
274 		   ("malloc(M_WAITOK) in interrupt context"));
275 	if (size <= KMEM_ZMAX) {
276 		if (size & KMEM_ZMASK)
277 			size = (size & ~KMEM_ZMASK) + KMEM_ZBASE;
278 		indx = kmemsize[size >> KMEM_ZSHIFT];
279 		zone = kmemzones[indx].kz_zone;
280 		keg = zone->uz_keg;
281 #ifdef MALLOC_PROFILE
282 		krequests[size >> KMEM_ZSHIFT]++;
283 #endif
284 		va = uma_zalloc(zone, flags);
285 		if (va != NULL)
286 			size = keg->uk_size;
287 		malloc_type_zone_allocated(type, va == NULL ? 0 : size, indx);
288 	} else {
289 		size = roundup(size, PAGE_SIZE);
290 		zone = NULL;
291 		keg = NULL;
292 		va = uma_large_malloc(size, flags);
293 		malloc_type_allocated(type, va == NULL ? 0 : size);
294 	}
295 	if (flags & M_WAITOK)
296 		KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL"));
297 	else if (va == NULL)
298 		t_malloc_fail = time_uptime;
299 #ifdef DIAGNOSTIC
300 	if (va != NULL && !(flags & M_ZERO)) {
301 		memset(va, 0x70, osize);
302 	}
303 #endif
304 	return ((void *) va);
305 }
306 
307 /*
308  *	free:
309  *
310  *	Free a block of memory allocated by malloc.
311  *
312  *	This routine may not block.
313  */
314 void
315 free(addr, type)
316 	void *addr;
317 	struct malloc_type *type;
318 {
319 	uma_slab_t slab;
320 	u_long size;
321 
322 	/* free(NULL, ...) does nothing */
323 	if (addr == NULL)
324 		return;
325 
326 	KASSERT(type->ks_memuse > 0,
327 		("malloc(9)/free(9) confusion.\n%s",
328 		 "Probably freeing with wrong type, but maybe not here."));
329 	size = 0;
330 
331 	slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK));
332 
333 	if (slab == NULL)
334 		panic("free: address %p(%p) has not been allocated.\n",
335 		    addr, (void *)((u_long)addr & (~UMA_SLAB_MASK)));
336 
337 
338 	if (!(slab->us_flags & UMA_SLAB_MALLOC)) {
339 #ifdef INVARIANTS
340 		struct malloc_type **mtp = addr;
341 #endif
342 		size = slab->us_keg->uk_size;
343 #ifdef INVARIANTS
344 		/*
345 		 * Cache a pointer to the malloc_type that most recently freed
346 		 * this memory here.  This way we know who is most likely to
347 		 * have stepped on it later.
348 		 *
349 		 * This code assumes that size is a multiple of 8 bytes for
350 		 * 64 bit machines
351 		 */
352 		mtp = (struct malloc_type **)
353 		    ((unsigned long)mtp & ~UMA_ALIGN_PTR);
354 		mtp += (size - sizeof(struct malloc_type *)) /
355 		    sizeof(struct malloc_type *);
356 		*mtp = type;
357 #endif
358 		uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab);
359 	} else {
360 		size = slab->us_size;
361 		uma_large_free(slab);
362 	}
363 	malloc_type_freed(type, size);
364 }
365 
366 /*
367  *	realloc: change the size of a memory block
368  */
369 void *
370 realloc(addr, size, type, flags)
371 	void *addr;
372 	unsigned long size;
373 	struct malloc_type *type;
374 	int flags;
375 {
376 	uma_slab_t slab;
377 	unsigned long alloc;
378 	void *newaddr;
379 
380 	/* realloc(NULL, ...) is equivalent to malloc(...) */
381 	if (addr == NULL)
382 		return (malloc(size, type, flags));
383 
384 	slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK));
385 
386 	/* Sanity check */
387 	KASSERT(slab != NULL,
388 	    ("realloc: address %p out of range", (void *)addr));
389 
390 	/* Get the size of the original block */
391 	if (slab->us_keg)
392 		alloc = slab->us_keg->uk_size;
393 	else
394 		alloc = slab->us_size;
395 
396 	/* Reuse the original block if appropriate */
397 	if (size <= alloc
398 	    && (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE))
399 		return (addr);
400 
401 	/* Allocate a new, bigger (or smaller) block */
402 	if ((newaddr = malloc(size, type, flags)) == NULL)
403 		return (NULL);
404 
405 	/* Copy over original contents */
406 	bcopy(addr, newaddr, min(size, alloc));
407 	free(addr, type);
408 	return (newaddr);
409 }
410 
411 /*
412  *	reallocf: same as realloc() but free memory on failure.
413  */
414 void *
415 reallocf(addr, size, type, flags)
416 	void *addr;
417 	unsigned long size;
418 	struct malloc_type *type;
419 	int flags;
420 {
421 	void *mem;
422 
423 	if ((mem = realloc(addr, size, type, flags)) == NULL)
424 		free(addr, type);
425 	return (mem);
426 }
427 
428 /*
429  * Initialize the kernel memory allocator
430  */
431 /* ARGSUSED*/
432 static void
433 kmeminit(dummy)
434 	void *dummy;
435 {
436 	u_int8_t indx;
437 	u_long mem_size;
438 	int i;
439 
440 	mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF);
441 
442 	/*
443 	 * Try to auto-tune the kernel memory size, so that it is
444 	 * more applicable for a wider range of machine sizes.
445 	 * On an X86, a VM_KMEM_SIZE_SCALE value of 4 is good, while
446 	 * a VM_KMEM_SIZE of 12MB is a fair compromise.  The
447 	 * VM_KMEM_SIZE_MAX is dependent on the maximum KVA space
448 	 * available, and on an X86 with a total KVA space of 256MB,
449 	 * try to keep VM_KMEM_SIZE_MAX at 80MB or below.
450 	 *
451 	 * Note that the kmem_map is also used by the zone allocator,
452 	 * so make sure that there is enough space.
453 	 */
454 	vm_kmem_size = VM_KMEM_SIZE + nmbclusters * PAGE_SIZE;
455 	mem_size = cnt.v_page_count;
456 
457 #if defined(VM_KMEM_SIZE_SCALE)
458 	if ((mem_size / VM_KMEM_SIZE_SCALE) > (vm_kmem_size / PAGE_SIZE))
459 		vm_kmem_size = (mem_size / VM_KMEM_SIZE_SCALE) * PAGE_SIZE;
460 #endif
461 
462 #if defined(VM_KMEM_SIZE_MAX)
463 	if (vm_kmem_size >= VM_KMEM_SIZE_MAX)
464 		vm_kmem_size = VM_KMEM_SIZE_MAX;
465 #endif
466 
467 	/* Allow final override from the kernel environment */
468 #ifndef BURN_BRIDGES
469 	if (TUNABLE_INT_FETCH("kern.vm.kmem.size", &vm_kmem_size) != 0)
470 		printf("kern.vm.kmem.size is now called vm.kmem_size!\n");
471 #endif
472 	TUNABLE_INT_FETCH("vm.kmem_size", &vm_kmem_size);
473 
474 	/*
475 	 * Limit kmem virtual size to twice the physical memory.
476 	 * This allows for kmem map sparseness, but limits the size
477 	 * to something sane. Be careful to not overflow the 32bit
478 	 * ints while doing the check.
479 	 */
480 	if (((vm_kmem_size / 2) / PAGE_SIZE) > cnt.v_page_count)
481 		vm_kmem_size = 2 * cnt.v_page_count * PAGE_SIZE;
482 
483 	/*
484 	 * Tune settings based on the kernel map's size at this time.
485 	 */
486 	init_param3(vm_kmem_size / PAGE_SIZE);
487 
488 	kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase,
489 		(vm_offset_t *)&kmemlimit, vm_kmem_size);
490 	kmem_map->system_map = 1;
491 
492 	uma_startup2();
493 
494 	for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) {
495 		int size = kmemzones[indx].kz_size;
496 		char *name = kmemzones[indx].kz_name;
497 
498 		kmemzones[indx].kz_zone = uma_zcreate(name, size,
499 #ifdef INVARIANTS
500 		    mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini,
501 #else
502 		    NULL, NULL, NULL, NULL,
503 #endif
504 		    UMA_ALIGN_PTR, UMA_ZONE_MALLOC);
505 
506 		for (;i <= size; i+= KMEM_ZBASE)
507 			kmemsize[i >> KMEM_ZSHIFT] = indx;
508 
509 	}
510 }
511 
512 void
513 malloc_init(data)
514 	void *data;
515 {
516 	struct malloc_type *type = (struct malloc_type *)data;
517 
518 	mtx_lock(&malloc_mtx);
519 	if (type->ks_magic != M_MAGIC)
520 		panic("malloc type lacks magic");
521 
522 	if (cnt.v_page_count == 0)
523 		panic("malloc_init not allowed before vm init");
524 
525 	if (type->ks_next != NULL)
526 		return;
527 
528 	type->ks_next = kmemstatistics;
529 	kmemstatistics = type;
530 	mtx_init(&type->ks_mtx, type->ks_shortdesc, "Malloc Stats", MTX_DEF);
531 	mtx_unlock(&malloc_mtx);
532 }
533 
534 void
535 malloc_uninit(data)
536 	void *data;
537 {
538 	struct malloc_type *type = (struct malloc_type *)data;
539 	struct malloc_type *t;
540 
541 	mtx_lock(&malloc_mtx);
542 	mtx_lock(&type->ks_mtx);
543 	if (type->ks_magic != M_MAGIC)
544 		panic("malloc type lacks magic");
545 
546 	if (cnt.v_page_count == 0)
547 		panic("malloc_uninit not allowed before vm init");
548 
549 	if (type == kmemstatistics)
550 		kmemstatistics = type->ks_next;
551 	else {
552 		for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) {
553 			if (t->ks_next == type) {
554 				t->ks_next = type->ks_next;
555 				break;
556 			}
557 		}
558 	}
559 	type->ks_next = NULL;
560 	mtx_destroy(&type->ks_mtx);
561 	mtx_unlock(&malloc_mtx);
562 }
563 
564 static int
565 sysctl_kern_malloc(SYSCTL_HANDLER_ARGS)
566 {
567 	struct malloc_type *type;
568 	int linesize = 128;
569 	int curline;
570 	int bufsize;
571 	int first;
572 	int error;
573 	char *buf;
574 	char *p;
575 	int cnt;
576 	int len;
577 	int i;
578 
579 	cnt = 0;
580 
581 	mtx_lock(&malloc_mtx);
582 	for (type = kmemstatistics; type != NULL; type = type->ks_next)
583 		cnt++;
584 
585 	mtx_unlock(&malloc_mtx);
586 	bufsize = linesize * (cnt + 1);
587 	p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO);
588 	mtx_lock(&malloc_mtx);
589 
590 	len = snprintf(p, linesize,
591 	    "\n        Type  InUse MemUse HighUse Requests  Size(s)\n");
592 	p += len;
593 
594 	for (type = kmemstatistics; cnt != 0 && type != NULL;
595 	    type = type->ks_next, cnt--) {
596 		if (type->ks_calls == 0)
597 			continue;
598 
599 		curline = linesize - 2;	/* Leave room for the \n */
600 		len = snprintf(p, curline, "%13s%6lu%6luK%7luK%9llu",
601 			type->ks_shortdesc,
602 			type->ks_inuse,
603 			(type->ks_memuse + 1023) / 1024,
604 			(type->ks_maxused + 1023) / 1024,
605 			(long long unsigned)type->ks_calls);
606 		curline -= len;
607 		p += len;
608 
609 		first = 1;
610 		for (i = 0; i < sizeof(kmemzones) / sizeof(kmemzones[0]) - 1;
611 		    i++) {
612 			if (type->ks_size & (1 << i)) {
613 				if (first)
614 					len = snprintf(p, curline, "  ");
615 				else
616 					len = snprintf(p, curline, ",");
617 				curline -= len;
618 				p += len;
619 
620 				len = snprintf(p, curline,
621 				    "%s", kmemzones[i].kz_name);
622 				curline -= len;
623 				p += len;
624 
625 				first = 0;
626 			}
627 		}
628 
629 		len = snprintf(p, 2, "\n");
630 		p += len;
631 	}
632 
633 	mtx_unlock(&malloc_mtx);
634 	error = SYSCTL_OUT(req, buf, p - buf);
635 
636 	free(buf, M_TEMP);
637 	return (error);
638 }
639 
640 SYSCTL_OID(_kern, OID_AUTO, malloc, CTLTYPE_STRING|CTLFLAG_RD,
641     NULL, 0, sysctl_kern_malloc, "A", "Malloc Stats");
642 
643 #ifdef MALLOC_PROFILE
644 
645 static int
646 sysctl_kern_mprof(SYSCTL_HANDLER_ARGS)
647 {
648 	int linesize = 64;
649 	uint64_t count;
650 	uint64_t waste;
651 	uint64_t mem;
652 	int bufsize;
653 	int error;
654 	char *buf;
655 	int rsize;
656 	int size;
657 	char *p;
658 	int len;
659 	int i;
660 
661 	bufsize = linesize * (KMEM_ZSIZE + 1);
662 	bufsize += 128; 	/* For the stats line */
663 	bufsize += 128; 	/* For the banner line */
664 	waste = 0;
665 	mem = 0;
666 
667 	p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO);
668 	len = snprintf(p, bufsize,
669 	    "\n  Size                    Requests  Real Size\n");
670 	bufsize -= len;
671 	p += len;
672 
673 	for (i = 0; i < KMEM_ZSIZE; i++) {
674 		size = i << KMEM_ZSHIFT;
675 		rsize = kmemzones[kmemsize[i]].kz_size;
676 		count = (long long unsigned)krequests[i];
677 
678 		len = snprintf(p, bufsize, "%6d%28llu%11d\n",
679 		    size, (unsigned long long)count, rsize);
680 		bufsize -= len;
681 		p += len;
682 
683 		if ((rsize * count) > (size * count))
684 			waste += (rsize * count) - (size * count);
685 		mem += (rsize * count);
686 	}
687 
688 	len = snprintf(p, bufsize,
689 	    "\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n",
690 	    (unsigned long long)mem, (unsigned long long)waste);
691 	p += len;
692 
693 	error = SYSCTL_OUT(req, buf, p - buf);
694 
695 	free(buf, M_TEMP);
696 	return (error);
697 }
698 
699 SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD,
700     NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling");
701 #endif /* MALLOC_PROFILE */
702