freebsd-skq/sys/kern/kern_malloc.c
bmilekic da7116f3ac Bring in MemGuard, a very simple and small replacement allocator
designed to help detect tamper-after-free scenarios, a problem more
and more common and likely with multithreaded kernels where race
conditions are more prevalent.

Currently MemGuard can only take over malloc()/realloc()/free() for
particular (a) malloc type(s) and the code brought in with this
change manually instruments it to take over M_SUBPROC allocations
as an example.  If you are planning to use it, for now you must:

	1) Put "options DEBUG_MEMGUARD" in your kernel config.
	2) Edit src/sys/kern/kern_malloc.c manually, look for
	   "XXX CHANGEME" and replace the M_SUBPROC comparison with
	   the appropriate malloc type (this might require additional
	   but small/simple code modification if, say, the malloc type
	   is declared out of scope).
	3) Build and install your kernel.  Tune vm.memguard_divisor
	   boot-time tunable which is used to scale how much of kmem_map
	   you want to allott for MemGuard's use.  The default is 10,
	   so kmem_size/10.

ToDo:
	1) Bring in a memguard(9) man page.
	2) Better instrumentation (e.g., boot-time) of MemGuard taking
	   over malloc types.
	3) Teach UMA about MemGuard to allow MemGuard to override zone
	   allocations too.
	4) Improve MemGuard if necessary.

This work is partly based on some old patches from Ian Dowse.
2005-01-21 18:09:17 +00:00

768 lines
19 KiB
C

/*-
* Copyright (c) 1987, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_malloc.c 8.3 (Berkeley) 1/4/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_vm.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/vmmeter.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>
#include <vm/vm_map.h>
#include <vm/vm_page.h>
#include <vm/uma.h>
#include <vm/uma_int.h>
#include <vm/uma_dbg.h>
#ifdef DEBUG_MEMGUARD
#include <vm/memguard.h>
#endif
#if defined(INVARIANTS) && defined(__i386__)
#include <machine/cpu.h>
#endif
/*
* When realloc() is called, if the new size is sufficiently smaller than
* the old size, realloc() will allocate a new, smaller block to avoid
* wasting memory. 'Sufficiently smaller' is defined as: newsize <=
* oldsize / 2^n, where REALLOC_FRACTION defines the value of 'n'.
*/
#ifndef REALLOC_FRACTION
#define REALLOC_FRACTION 1 /* new block if <= half the size */
#endif
MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches");
MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers");
MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery");
static void kmeminit(void *);
SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, kmeminit, NULL)
static MALLOC_DEFINE(M_FREE, "free", "should be on free list");
static struct malloc_type *kmemstatistics;
static char *kmembase;
static char *kmemlimit;
#define KMEM_ZSHIFT 4
#define KMEM_ZBASE 16
#define KMEM_ZMASK (KMEM_ZBASE - 1)
#define KMEM_ZMAX PAGE_SIZE
#define KMEM_ZSIZE (KMEM_ZMAX >> KMEM_ZSHIFT)
static u_int8_t kmemsize[KMEM_ZSIZE + 1];
/* These won't be powers of two for long */
struct {
int kz_size;
char *kz_name;
uma_zone_t kz_zone;
} kmemzones[] = {
{16, "16", NULL},
{32, "32", NULL},
{64, "64", NULL},
{128, "128", NULL},
{256, "256", NULL},
{512, "512", NULL},
{1024, "1024", NULL},
{2048, "2048", NULL},
{4096, "4096", NULL},
#if PAGE_SIZE > 4096
{8192, "8192", NULL},
#if PAGE_SIZE > 8192
{16384, "16384", NULL},
#if PAGE_SIZE > 16384
{32768, "32768", NULL},
#if PAGE_SIZE > 32768
{65536, "65536", NULL},
#if PAGE_SIZE > 65536
#error "Unsupported PAGE_SIZE"
#endif /* 65536 */
#endif /* 32768 */
#endif /* 16384 */
#endif /* 8192 */
#endif /* 4096 */
{0, NULL},
};
#ifdef DEBUG_MEMGUARD
u_int vm_memguard_divisor;
SYSCTL_UINT(_vm, OID_AUTO, memguard_divisor, CTLFLAG_RD, &vm_memguard_divisor,
0, "(kmem_size/memguard_divisor) == memguard submap size");
#endif
u_int vm_kmem_size;
SYSCTL_UINT(_vm, OID_AUTO, kmem_size, CTLFLAG_RD, &vm_kmem_size, 0,
"Size of kernel memory");
u_int vm_kmem_size_max;
SYSCTL_UINT(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RD, &vm_kmem_size_max, 0,
"Maximum size of kernel memory");
u_int vm_kmem_size_scale;
SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RD, &vm_kmem_size_scale, 0,
"Scale factor for kernel memory size");
/*
* The malloc_mtx protects the kmemstatistics linked list.
*/
struct mtx malloc_mtx;
#ifdef MALLOC_PROFILE
uint64_t krequests[KMEM_ZSIZE + 1];
static int sysctl_kern_mprof(SYSCTL_HANDLER_ARGS);
#endif
static int sysctl_kern_malloc(SYSCTL_HANDLER_ARGS);
/* time_uptime of last malloc(9) failure */
static time_t t_malloc_fail;
#ifdef MALLOC_MAKE_FAILURES
/*
* Causes malloc failures every (n) mallocs with M_NOWAIT. If set to 0,
* doesn't cause failures.
*/
SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD, 0,
"Kernel malloc debugging options");
static int malloc_failure_rate;
static int malloc_nowait_count;
static int malloc_failure_count;
SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RW,
&malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail");
TUNABLE_INT("debug.malloc.failure_rate", &malloc_failure_rate);
SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD,
&malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures");
#endif
int
malloc_last_fail(void)
{
return (time_uptime - t_malloc_fail);
}
/*
* Add this to the informational malloc_type bucket.
*/
static void
malloc_type_zone_allocated(struct malloc_type *ksp, unsigned long size,
int zindx)
{
mtx_lock(&ksp->ks_mtx);
ksp->ks_calls++;
if (zindx != -1)
ksp->ks_size |= 1 << zindx;
if (size != 0) {
ksp->ks_memuse += size;
ksp->ks_inuse++;
if (ksp->ks_memuse > ksp->ks_maxused)
ksp->ks_maxused = ksp->ks_memuse;
}
mtx_unlock(&ksp->ks_mtx);
}
void
malloc_type_allocated(struct malloc_type *ksp, unsigned long size)
{
malloc_type_zone_allocated(ksp, size, -1);
}
/*
* Remove this allocation from the informational malloc_type bucket.
*/
void
malloc_type_freed(struct malloc_type *ksp, unsigned long size)
{
mtx_lock(&ksp->ks_mtx);
KASSERT(size <= ksp->ks_memuse,
("malloc(9)/free(9) confusion.\n%s",
"Probably freeing with wrong type, but maybe not here."));
ksp->ks_memuse -= size;
ksp->ks_inuse--;
mtx_unlock(&ksp->ks_mtx);
}
/*
* malloc:
*
* Allocate a block of memory.
*
* If M_NOWAIT is set, this routine will not block and return NULL if
* the allocation fails.
*/
void *
malloc(size, type, flags)
unsigned long size;
struct malloc_type *type;
int flags;
{
int indx;
caddr_t va;
uma_zone_t zone;
uma_keg_t keg;
#ifdef DIAGNOSTIC
unsigned long osize = size;
#endif
#ifdef INVARIANTS
/*
* To make sure that WAITOK or NOWAIT is set, but not more than
* one, and check against the API botches that are common.
*/
indx = flags & (M_WAITOK | M_NOWAIT | M_DONTWAIT | M_TRYWAIT);
if (indx != M_NOWAIT && indx != M_WAITOK) {
static struct timeval lasterr;
static int curerr, once;
if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) {
printf("Bad malloc flags: %x\n", indx);
kdb_backtrace();
flags |= M_WAITOK;
once++;
}
}
#endif
#if 0
if (size == 0)
kdb_enter("zero size malloc");
#endif
#ifdef MALLOC_MAKE_FAILURES
if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) {
atomic_add_int(&malloc_nowait_count, 1);
if ((malloc_nowait_count % malloc_failure_rate) == 0) {
atomic_add_int(&malloc_failure_count, 1);
t_malloc_fail = time_uptime;
return (NULL);
}
}
#endif
if (flags & M_WAITOK)
KASSERT(curthread->td_intr_nesting_level == 0,
("malloc(M_WAITOK) in interrupt context"));
#ifdef DEBUG_MEMGUARD
/* XXX CHANGEME! */
if (type == M_SUBPROC)
return memguard_alloc(size, flags);
#endif
if (size <= KMEM_ZMAX) {
if (size & KMEM_ZMASK)
size = (size & ~KMEM_ZMASK) + KMEM_ZBASE;
indx = kmemsize[size >> KMEM_ZSHIFT];
zone = kmemzones[indx].kz_zone;
keg = zone->uz_keg;
#ifdef MALLOC_PROFILE
krequests[size >> KMEM_ZSHIFT]++;
#endif
va = uma_zalloc(zone, flags);
if (va != NULL)
size = keg->uk_size;
malloc_type_zone_allocated(type, va == NULL ? 0 : size, indx);
} else {
size = roundup(size, PAGE_SIZE);
zone = NULL;
keg = NULL;
va = uma_large_malloc(size, flags);
malloc_type_allocated(type, va == NULL ? 0 : size);
}
if (flags & M_WAITOK)
KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL"));
else if (va == NULL)
t_malloc_fail = time_uptime;
#ifdef DIAGNOSTIC
if (va != NULL && !(flags & M_ZERO)) {
memset(va, 0x70, osize);
}
#endif
return ((void *) va);
}
/*
* free:
*
* Free a block of memory allocated by malloc.
*
* This routine may not block.
*/
void
free(addr, type)
void *addr;
struct malloc_type *type;
{
uma_slab_t slab;
u_long size;
/* free(NULL, ...) does nothing */
if (addr == NULL)
return;
#ifdef DEBUG_MEMGUARD
/* XXX CHANGEME! */
if (type == M_SUBPROC) {
memguard_free(addr);
return;
}
#endif
KASSERT(type->ks_memuse > 0,
("malloc(9)/free(9) confusion.\n%s",
"Probably freeing with wrong type, but maybe not here."));
size = 0;
slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK));
if (slab == NULL)
panic("free: address %p(%p) has not been allocated.\n",
addr, (void *)((u_long)addr & (~UMA_SLAB_MASK)));
if (!(slab->us_flags & UMA_SLAB_MALLOC)) {
#ifdef INVARIANTS
struct malloc_type **mtp = addr;
#endif
size = slab->us_keg->uk_size;
#ifdef INVARIANTS
/*
* Cache a pointer to the malloc_type that most recently freed
* this memory here. This way we know who is most likely to
* have stepped on it later.
*
* This code assumes that size is a multiple of 8 bytes for
* 64 bit machines
*/
mtp = (struct malloc_type **)
((unsigned long)mtp & ~UMA_ALIGN_PTR);
mtp += (size - sizeof(struct malloc_type *)) /
sizeof(struct malloc_type *);
*mtp = type;
#endif
uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab);
} else {
size = slab->us_size;
uma_large_free(slab);
}
malloc_type_freed(type, size);
}
/*
* realloc: change the size of a memory block
*/
void *
realloc(addr, size, type, flags)
void *addr;
unsigned long size;
struct malloc_type *type;
int flags;
{
uma_slab_t slab;
unsigned long alloc;
void *newaddr;
/* realloc(NULL, ...) is equivalent to malloc(...) */
if (addr == NULL)
return (malloc(size, type, flags));
#ifdef DEBUG_MEMGUARD
/* XXX: CHANGEME! */
if (type == M_SUBPROC) {
slab = NULL;
alloc = size;
} else {
#endif
slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK));
/* Sanity check */
KASSERT(slab != NULL,
("realloc: address %p out of range", (void *)addr));
/* Get the size of the original block */
if (slab->us_keg)
alloc = slab->us_keg->uk_size;
else
alloc = slab->us_size;
/* Reuse the original block if appropriate */
if (size <= alloc
&& (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE))
return (addr);
#ifdef DEBUG_MEMGUARD
}
#endif
/* Allocate a new, bigger (or smaller) block */
if ((newaddr = malloc(size, type, flags)) == NULL)
return (NULL);
/* Copy over original contents */
bcopy(addr, newaddr, min(size, alloc));
free(addr, type);
return (newaddr);
}
/*
* reallocf: same as realloc() but free memory on failure.
*/
void *
reallocf(addr, size, type, flags)
void *addr;
unsigned long size;
struct malloc_type *type;
int flags;
{
void *mem;
if ((mem = realloc(addr, size, type, flags)) == NULL)
free(addr, type);
return (mem);
}
/*
* Initialize the kernel memory allocator
*/
/* ARGSUSED*/
static void
kmeminit(dummy)
void *dummy;
{
u_int8_t indx;
u_long mem_size;
int i;
mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF);
/*
* Try to auto-tune the kernel memory size, so that it is
* more applicable for a wider range of machine sizes.
* On an X86, a VM_KMEM_SIZE_SCALE value of 4 is good, while
* a VM_KMEM_SIZE of 12MB is a fair compromise. The
* VM_KMEM_SIZE_MAX is dependent on the maximum KVA space
* available, and on an X86 with a total KVA space of 256MB,
* try to keep VM_KMEM_SIZE_MAX at 80MB or below.
*
* Note that the kmem_map is also used by the zone allocator,
* so make sure that there is enough space.
*/
vm_kmem_size = VM_KMEM_SIZE + nmbclusters * PAGE_SIZE;
mem_size = cnt.v_page_count;
#if defined(VM_KMEM_SIZE_SCALE)
vm_kmem_size_scale = VM_KMEM_SIZE_SCALE;
#endif
TUNABLE_INT_FETCH("vm.kmem_size_scale", &vm_kmem_size_scale);
if (vm_kmem_size_scale > 0 &&
(mem_size / vm_kmem_size_scale) > (vm_kmem_size / PAGE_SIZE))
vm_kmem_size = (mem_size / vm_kmem_size_scale) * PAGE_SIZE;
#if defined(VM_KMEM_SIZE_MAX)
vm_kmem_size_max = VM_KMEM_SIZE_MAX;
#endif
TUNABLE_INT_FETCH("vm.kmem_size_max", &vm_kmem_size_max);
if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max)
vm_kmem_size = vm_kmem_size_max;
/* Allow final override from the kernel environment */
#ifndef BURN_BRIDGES
if (TUNABLE_INT_FETCH("kern.vm.kmem.size", &vm_kmem_size) != 0)
printf("kern.vm.kmem.size is now called vm.kmem_size!\n");
#endif
TUNABLE_INT_FETCH("vm.kmem_size", &vm_kmem_size);
/*
* Limit kmem virtual size to twice the physical memory.
* This allows for kmem map sparseness, but limits the size
* to something sane. Be careful to not overflow the 32bit
* ints while doing the check.
*/
if (((vm_kmem_size / 2) / PAGE_SIZE) > cnt.v_page_count)
vm_kmem_size = 2 * cnt.v_page_count * PAGE_SIZE;
/*
* Tune settings based on the kernel map's size at this time.
*/
init_param3(vm_kmem_size / PAGE_SIZE);
kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase,
(vm_offset_t *)&kmemlimit, vm_kmem_size);
kmem_map->system_map = 1;
#ifdef DEBUG_MEMGUARD
/*
* Initialize MemGuard if support compiled in. MemGuard is a
* replacement allocator used for detecting tamper-after-free
* scenarios as they occur. It is only used for debugging.
*/
vm_memguard_divisor = 10;
TUNABLE_INT_FETCH("vm.memguard_divisor", &vm_memguard_divisor);
/* Pick a conservative value if provided value sucks. */
if ((vm_memguard_divisor <= 0) ||
((vm_kmem_size / vm_memguard_divisor) == 0))
vm_memguard_divisor = 10;
memguard_init(kmem_map, vm_kmem_size / vm_memguard_divisor);
#endif
uma_startup2();
for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) {
int size = kmemzones[indx].kz_size;
char *name = kmemzones[indx].kz_name;
kmemzones[indx].kz_zone = uma_zcreate(name, size,
#ifdef INVARIANTS
mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini,
#else
NULL, NULL, NULL, NULL,
#endif
UMA_ALIGN_PTR, UMA_ZONE_MALLOC);
for (;i <= size; i+= KMEM_ZBASE)
kmemsize[i >> KMEM_ZSHIFT] = indx;
}
}
void
malloc_init(data)
void *data;
{
struct malloc_type *type = (struct malloc_type *)data;
mtx_lock(&malloc_mtx);
if (type->ks_magic != M_MAGIC)
panic("malloc type lacks magic");
if (cnt.v_page_count == 0)
panic("malloc_init not allowed before vm init");
if (type->ks_next != NULL)
return;
type->ks_next = kmemstatistics;
kmemstatistics = type;
mtx_init(&type->ks_mtx, type->ks_shortdesc, "Malloc Stats", MTX_DEF);
mtx_unlock(&malloc_mtx);
}
void
malloc_uninit(data)
void *data;
{
struct malloc_type *type = (struct malloc_type *)data;
struct malloc_type *t;
mtx_lock(&malloc_mtx);
mtx_lock(&type->ks_mtx);
if (type->ks_magic != M_MAGIC)
panic("malloc type lacks magic");
if (cnt.v_page_count == 0)
panic("malloc_uninit not allowed before vm init");
if (type == kmemstatistics)
kmemstatistics = type->ks_next;
else {
for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) {
if (t->ks_next == type) {
t->ks_next = type->ks_next;
break;
}
}
}
type->ks_next = NULL;
mtx_destroy(&type->ks_mtx);
mtx_unlock(&malloc_mtx);
}
static int
sysctl_kern_malloc(SYSCTL_HANDLER_ARGS)
{
struct malloc_type *type;
int linesize = 128;
int curline;
int bufsize;
int first;
int error;
char *buf;
char *p;
int cnt;
int len;
int i;
cnt = 0;
mtx_lock(&malloc_mtx);
for (type = kmemstatistics; type != NULL; type = type->ks_next)
cnt++;
mtx_unlock(&malloc_mtx);
bufsize = linesize * (cnt + 1);
p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO);
mtx_lock(&malloc_mtx);
len = snprintf(p, linesize,
"\n Type InUse MemUse HighUse Requests Size(s)\n");
p += len;
for (type = kmemstatistics; cnt != 0 && type != NULL;
type = type->ks_next, cnt--) {
if (type->ks_calls == 0)
continue;
curline = linesize - 2; /* Leave room for the \n */
len = snprintf(p, curline, "%13s%6lu%6luK%7luK%9llu",
type->ks_shortdesc,
type->ks_inuse,
(type->ks_memuse + 1023) / 1024,
(type->ks_maxused + 1023) / 1024,
(long long unsigned)type->ks_calls);
curline -= len;
p += len;
first = 1;
for (i = 0; i < sizeof(kmemzones) / sizeof(kmemzones[0]) - 1;
i++) {
if (type->ks_size & (1 << i)) {
if (first)
len = snprintf(p, curline, " ");
else
len = snprintf(p, curline, ",");
curline -= len;
p += len;
len = snprintf(p, curline,
"%s", kmemzones[i].kz_name);
curline -= len;
p += len;
first = 0;
}
}
len = snprintf(p, 2, "\n");
p += len;
}
mtx_unlock(&malloc_mtx);
error = SYSCTL_OUT(req, buf, p - buf);
free(buf, M_TEMP);
return (error);
}
SYSCTL_OID(_kern, OID_AUTO, malloc, CTLTYPE_STRING|CTLFLAG_RD,
NULL, 0, sysctl_kern_malloc, "A", "Malloc Stats");
#ifdef MALLOC_PROFILE
static int
sysctl_kern_mprof(SYSCTL_HANDLER_ARGS)
{
int linesize = 64;
uint64_t count;
uint64_t waste;
uint64_t mem;
int bufsize;
int error;
char *buf;
int rsize;
int size;
char *p;
int len;
int i;
bufsize = linesize * (KMEM_ZSIZE + 1);
bufsize += 128; /* For the stats line */
bufsize += 128; /* For the banner line */
waste = 0;
mem = 0;
p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO);
len = snprintf(p, bufsize,
"\n Size Requests Real Size\n");
bufsize -= len;
p += len;
for (i = 0; i < KMEM_ZSIZE; i++) {
size = i << KMEM_ZSHIFT;
rsize = kmemzones[kmemsize[i]].kz_size;
count = (long long unsigned)krequests[i];
len = snprintf(p, bufsize, "%6d%28llu%11d\n",
size, (unsigned long long)count, rsize);
bufsize -= len;
p += len;
if ((rsize * count) > (size * count))
waste += (rsize * count) - (size * count);
mem += (rsize * count);
}
len = snprintf(p, bufsize,
"\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n",
(unsigned long long)mem, (unsigned long long)waste);
p += len;
error = SYSCTL_OUT(req, buf, p - buf);
free(buf, M_TEMP);
return (error);
}
SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD,
NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling");
#endif /* MALLOC_PROFILE */