FreeBSD-5.3/sys/kern/kern_malloc.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: src/sys/kern/kern_malloc.c,v 1.135.2.1 2004/10/03 23:44:31 des Exp $");
#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>
#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},
};
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"));
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;
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));
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);
/* 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;
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 */