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8055acd82d
freebsd/sys/kern/kern_malloc.c
Bosko Milekic 9ed346bab0 Change and clean the mutex lock interface. 
mtx_enter(lock, type) becomes:

mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)

similarily, for releasing a lock, we now have:

mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.

The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.

Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:

MTX_QUIET and MTX_NOSWITCH

The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:

mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.

Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.

Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.

Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.

Finally, caught up to the interface changes in all sys code.

Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00

574 lines
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/*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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
* $FreeBSD$
*/
#include "opt_vm.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/vmmeter.h>
#include <sys/lock.h>
#include <sys/proc.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#if defined(INVARIANTS) && defined(__i386__)
#include <machine/cpu.h>
#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 __P((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 struct kmembuckets bucket[MINBUCKET + 16];
static struct kmemusage *kmemusage;
static char *kmembase;
static char *kmemlimit;
static struct mtx malloc_mtx;
u_int vm_kmem_size;
#ifdef INVARIANTS
/*
* This structure provides a set of masks to catch unaligned frees.
*/
static long addrmask[] = { 0,
0x00000001, 0x00000003, 0x00000007, 0x0000000f,
0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff,
0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff,
0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff,
};
/*
* The WEIRD_ADDR is used as known text to copy into free objects so
* that modifications after frees can be detected.
*/
#define WEIRD_ADDR 0xdeadc0de
#define MAX_COPY 64
/*
* Normally the first word of the structure is used to hold the list
* pointer for free objects. However, when running with diagnostics,
* we use the third and fourth fields, so as to catch modifications
* in the most commonly trashed first two words.
*/
struct freelist {
long spare0;
struct malloc_type *type;
long spare1;
caddr_t next;
};
#else /* !INVARIANTS */
struct freelist {
caddr_t next;
};
#endif /* INVARIANTS */
/*
* malloc:
*
* Allocate a block of memory.
*
* If M_NOWAIT is set, this routine will not block and return NULL if
* the allocation fails.
*
* If M_ASLEEP is set (M_NOWAIT must also be set), this routine
* will have the side effect of calling asleep() if it returns NULL,
* allowing the parent to await() at some future time.
*/
void *
malloc(size, type, flags)
unsigned long size;
struct malloc_type *type;
int flags;
{
register struct kmembuckets *kbp;
register struct kmemusage *kup;
register struct freelist *freep;
long indx, npg, allocsize;
int s;
caddr_t va, cp, savedlist;
#ifdef INVARIANTS
long *end, *lp;
int copysize;
const char *savedtype;
#endif
register struct malloc_type *ksp = type;
#if defined(INVARIANTS)
if (flags == M_WAITOK)
KASSERT(curproc->p_intr_nesting_level == 0,
("malloc(M_WAITOK) in interrupt context"));
#endif
indx = BUCKETINDX(size);
kbp = &bucket[indx];
s = splmem();
mtx_lock(&malloc_mtx);
while (ksp->ks_memuse >= ksp->ks_limit) {
if (flags & M_ASLEEP) {
if (ksp->ks_limblocks < 65535)
ksp->ks_limblocks++;
asleep((caddr_t)ksp, PSWP+2, type->ks_shortdesc, 0);
}
if (flags & M_NOWAIT) {
splx(s);
mtx_unlock(&malloc_mtx);
return ((void *) NULL);
}
if (ksp->ks_limblocks < 65535)
ksp->ks_limblocks++;
msleep((caddr_t)ksp, &malloc_mtx, PSWP+2, type->ks_shortdesc,
0);
}
ksp->ks_size |= 1 << indx;
#ifdef INVARIANTS
copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY;
#endif
if (kbp->kb_next == NULL) {
kbp->kb_last = NULL;
if (size > MAXALLOCSAVE)
allocsize = roundup(size, PAGE_SIZE);
else
allocsize = 1 << indx;
npg = btoc(allocsize);
mtx_unlock(&malloc_mtx);
va = (caddr_t) kmem_malloc(kmem_map, (vm_size_t)ctob(npg), flags);
if (va == NULL) {
splx(s);
return ((void *) NULL);
}
/*
* Enter malloc_mtx after the error check to avoid having to
* immediately exit it again if there is an error.
*/
mtx_lock(&malloc_mtx);
kbp->kb_total += kbp->kb_elmpercl;
kup = btokup(va);
kup->ku_indx = indx;
if (allocsize > MAXALLOCSAVE) {
if (npg > 65535)
panic("malloc: allocation too large");
kup->ku_pagecnt = npg;
ksp->ks_memuse += allocsize;
goto out;
}
kup->ku_freecnt = kbp->kb_elmpercl;
kbp->kb_totalfree += kbp->kb_elmpercl;
/*
* Just in case we blocked while allocating memory,
* and someone else also allocated memory for this
* bucket, don't assume the list is still empty.
*/
savedlist = kbp->kb_next;
kbp->kb_next = cp = va + (npg * PAGE_SIZE) - allocsize;
for (;;) {
freep = (struct freelist *)cp;
#ifdef INVARIANTS
/*
* Copy in known text to detect modification
* after freeing.
*/
end = (long *)&cp[copysize];
for (lp = (long *)cp; lp < end; lp++)
*lp = WEIRD_ADDR;
freep->type = M_FREE;
#endif /* INVARIANTS */
if (cp <= va)
break;
cp -= allocsize;
freep->next = cp;
}
freep->next = savedlist;
if (kbp->kb_last == NULL)
kbp->kb_last = (caddr_t)freep;
}
va = kbp->kb_next;
kbp->kb_next = ((struct freelist *)va)->next;
#ifdef INVARIANTS
freep = (struct freelist *)va;
savedtype = (const char *) freep->type->ks_shortdesc;
#if BYTE_ORDER == BIG_ENDIAN
freep->type = (struct malloc_type *)WEIRD_ADDR >> 16;
#endif
#if BYTE_ORDER == LITTLE_ENDIAN
freep->type = (struct malloc_type *)WEIRD_ADDR;
#endif
if ((intptr_t)(void *)&freep->next & 0x2)
freep->next = (caddr_t)((WEIRD_ADDR >> 16)|(WEIRD_ADDR << 16));
else
freep->next = (caddr_t)WEIRD_ADDR;
end = (long *)&va[copysize];
for (lp = (long *)va; lp < end; lp++) {
if (*lp == WEIRD_ADDR)
continue;
printf("%s %ld of object %p size %lu %s %s (0x%lx != 0x%lx)\n",
"Data modified on freelist: word",
(long)(lp - (long *)va), (void *)va, size,
"previous type", savedtype, *lp, (u_long)WEIRD_ADDR);
break;
}
freep->spare0 = 0;
#endif /* INVARIANTS */
kup = btokup(va);
if (kup->ku_indx != indx)
panic("malloc: wrong bucket");
if (kup->ku_freecnt == 0)
panic("malloc: lost data");
kup->ku_freecnt--;
kbp->kb_totalfree--;
ksp->ks_memuse += 1 << indx;
out:
kbp->kb_calls++;
ksp->ks_inuse++;
ksp->ks_calls++;
if (ksp->ks_memuse > ksp->ks_maxused)
ksp->ks_maxused = ksp->ks_memuse;
splx(s);
mtx_unlock(&malloc_mtx);
/* XXX: Do idle pre-zeroing. */
if (va != NULL && (flags & M_ZERO))
bzero(va, size);
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;
{
register struct kmembuckets *kbp;
register struct kmemusage *kup;
register struct freelist *freep;
long size;
int s;
#ifdef INVARIANTS
struct freelist *fp;
long *end, *lp, alloc, copysize;
#endif
register struct malloc_type *ksp = type;
KASSERT(kmembase <= (char *)addr && (char *)addr < kmemlimit,
("free: address %p out of range", (void *)addr));
kup = btokup(addr);
size = 1 << kup->ku_indx;
kbp = &bucket[kup->ku_indx];
s = splmem();
mtx_lock(&malloc_mtx);
#ifdef INVARIANTS
/*
* Check for returns of data that do not point to the
* beginning of the allocation.
*/
if (size > PAGE_SIZE)
alloc = addrmask[BUCKETINDX(PAGE_SIZE)];
else
alloc = addrmask[kup->ku_indx];
if (((uintptr_t)(void *)addr & alloc) != 0)
panic("free: unaligned addr %p, size %ld, type %s, mask %ld",
(void *)addr, size, type->ks_shortdesc, alloc);
#endif /* INVARIANTS */
if (size > MAXALLOCSAVE) {
mtx_unlock(&malloc_mtx);
kmem_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt));
mtx_lock(&malloc_mtx);
size = kup->ku_pagecnt << PAGE_SHIFT;
ksp->ks_memuse -= size;
kup->ku_indx = 0;
kup->ku_pagecnt = 0;
if (ksp->ks_memuse + size >= ksp->ks_limit &&
ksp->ks_memuse < ksp->ks_limit)
wakeup((caddr_t)ksp);
ksp->ks_inuse--;
kbp->kb_total -= 1;
splx(s);
mtx_unlock(&malloc_mtx);
return;
}
freep = (struct freelist *)addr;
#ifdef INVARIANTS
/*
* Check for multiple frees. Use a quick check to see if
* it looks free before laboriously searching the freelist.
*/
if (freep->spare0 == WEIRD_ADDR) {
fp = (struct freelist *)kbp->kb_next;
while (fp) {
if (fp->spare0 != WEIRD_ADDR)
panic("free: free item %p modified", fp);
else if (addr == (caddr_t)fp)
panic("free: multiple freed item %p", addr);
fp = (struct freelist *)fp->next;
}
}
/*
* Copy in known text to detect modification after freeing
* and to make it look free. Also, save the type being freed
* so we can list likely culprit if modification is detected
* when the object is reallocated.
*/
copysize = size < MAX_COPY ? size : MAX_COPY;
end = (long *)&((caddr_t)addr)[copysize];
for (lp = (long *)addr; lp < end; lp++)
*lp = WEIRD_ADDR;
freep->type = type;
#endif /* INVARIANTS */
kup->ku_freecnt++;
if (kup->ku_freecnt >= kbp->kb_elmpercl) {
if (kup->ku_freecnt > kbp->kb_elmpercl)
panic("free: multiple frees");
else if (kbp->kb_totalfree > kbp->kb_highwat)
kbp->kb_couldfree++;
}
kbp->kb_totalfree++;
ksp->ks_memuse -= size;
if (ksp->ks_memuse + size >= ksp->ks_limit &&
ksp->ks_memuse < ksp->ks_limit)
wakeup((caddr_t)ksp);
ksp->ks_inuse--;
#ifdef OLD_MALLOC_MEMORY_POLICY
if (kbp->kb_next == NULL)
kbp->kb_next = addr;
else
((struct freelist *)kbp->kb_last)->next = addr;
freep->next = NULL;
kbp->kb_last = addr;
#else
/*
* Return memory to the head of the queue for quick reuse. This
* can improve performance by improving the probability of the
* item being in the cache when it is reused.
*/
if (kbp->kb_next == NULL) {
kbp->kb_next = addr;
kbp->kb_last = addr;
freep->next = NULL;
} else {
freep->next = kbp->kb_next;
kbp->kb_next = addr;
}
#endif
splx(s);
mtx_unlock(&malloc_mtx);
}
/*
* Initialize the kernel memory allocator
*/
/* ARGSUSED*/
static void
kmeminit(dummy)
void *dummy;
{
register long indx;
u_long npg;
u_long mem_size;
u_long xvm_kmem_size;
#if ((MAXALLOCSAVE & (MAXALLOCSAVE - 1)) != 0)
#error "kmeminit: MAXALLOCSAVE not power of 2"
#endif
#if (MAXALLOCSAVE > MINALLOCSIZE * 32768)
#error "kmeminit: MAXALLOCSAVE too big"
#endif
#if (MAXALLOCSAVE < PAGE_SIZE)
#error "kmeminit: MAXALLOCSAVE too small"
#endif
mtx_init(&malloc_mtx, "malloc", 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.
*/
xvm_kmem_size = VM_KMEM_SIZE;
mem_size = cnt.v_page_count * PAGE_SIZE;
#if defined(VM_KMEM_SIZE_SCALE)
if ((mem_size / VM_KMEM_SIZE_SCALE) > xvm_kmem_size)
xvm_kmem_size = mem_size / VM_KMEM_SIZE_SCALE;
#endif
#if defined(VM_KMEM_SIZE_MAX)
if (xvm_kmem_size >= VM_KMEM_SIZE_MAX)
xvm_kmem_size = VM_KMEM_SIZE_MAX;
#endif
/* Allow final override from the kernel environment */
TUNABLE_INT_FETCH("kern.vm.kmem.size", xvm_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) > (cnt.v_page_count * PAGE_SIZE))
vm_kmem_size = 2 * cnt.v_page_count * PAGE_SIZE;
npg = (nmbufs * MSIZE + nmbclusters * MCLBYTES + vm_kmem_size)
/ PAGE_SIZE;
kmemusage = (struct kmemusage *) kmem_alloc(kernel_map,
(vm_size_t)(npg * sizeof(struct kmemusage)));
kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase,
(vm_offset_t *)&kmemlimit, (vm_size_t)(npg * PAGE_SIZE));
kmem_map->system_map = 1;
for (indx = 0; indx < MINBUCKET + 16; indx++) {
if (1 << indx >= PAGE_SIZE)
bucket[indx].kb_elmpercl = 1;
else
bucket[indx].kb_elmpercl = PAGE_SIZE / (1 << indx);
bucket[indx].kb_highwat = 5 * bucket[indx].kb_elmpercl;
}
}
void
malloc_init(data)
void *data;
{
struct malloc_type *type = (struct malloc_type *)data;
if (type->ks_magic != M_MAGIC)
panic("malloc type lacks magic");
if (type->ks_limit != 0)
return;
if (cnt.v_page_count == 0)
panic("malloc_init not allowed before vm init");
/*
* The default limits for each malloc region is 1/2 of the
* malloc portion of the kmem map size.
*/
type->ks_limit = vm_kmem_size / 2;
type->ks_next = kmemstatistics;
kmemstatistics = type;
}
void
malloc_uninit(data)
void *data;
{
struct malloc_type *type = (struct malloc_type *)data;
struct malloc_type *t;
#ifdef INVARIANTS
struct kmembuckets *kbp;
struct freelist *freep;
long indx;
int s;
#endif
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->ks_limit == 0)
panic("malloc_uninit on uninitialized type");
#ifdef INVARIANTS
s = splmem();
mtx_lock(&malloc_mtx);
for (indx = 0; indx < MINBUCKET + 16; indx++) {
kbp = bucket + indx;
freep = (struct freelist*)kbp->kb_next;
while (freep) {
if (freep->type == type)
freep->type = M_FREE;
freep = (struct freelist*)freep->next;
}
}
splx(s);
mtx_unlock(&malloc_mtx);
if (type->ks_memuse != 0)
printf("malloc_uninit: %ld bytes of '%s' still allocated\n",
type->ks_memuse, type->ks_shortdesc);
#endif
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;
type->ks_limit = 0;
}
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