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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)kern_malloc.c 8.3 (Berkeley) 1/4/94 34 * $FreeBSD$ 35 */ 36 37 #include "opt_vm.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/kernel.h> 42 #include <sys/lock.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/mutex.h> 46 #include <sys/vmmeter.h> 47 #include <sys/proc.h> 48 49 #include <vm/vm.h> 50 #include <vm/vm_param.h> 51 #include <vm/vm_kern.h> 52 #include <vm/vm_extern.h> 53 #include <vm/pmap.h> 54 #include <vm/vm_map.h> 55 56 #if defined(INVARIANTS) && defined(__i386__) 57 #include <machine/cpu.h> 58 #endif 59 60 MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches"); 61 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); 62 MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers"); 63 64 MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options"); 65 MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery"); 66 67 static void kmeminit __P((void *)); 68 SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, kmeminit, NULL) 69 70 static MALLOC_DEFINE(M_FREE, "free", "should be on free list"); 71 72 static struct malloc_type *kmemstatistics; 73 static struct kmembuckets bucket[MINBUCKET + 16]; 74 static struct kmemusage *kmemusage; 75 static char *kmembase; 76 static char *kmemlimit; 77 78 static struct mtx malloc_mtx; 79 80 u_int vm_kmem_size; 81 82 #ifdef INVARIANTS 83 /* 84 * This structure provides a set of masks to catch unaligned frees. 85 */ 86 static long addrmask[] = { 0, 87 0x00000001, 0x00000003, 0x00000007, 0x0000000f, 88 0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff, 89 0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff, 90 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff, 91 }; 92 93 /* 94 * The WEIRD_ADDR is used as known text to copy into free objects so 95 * that modifications after frees can be detected. 96 */ 97 #define WEIRD_ADDR 0xdeadc0de 98 #define MAX_COPY 64 99 100 /* 101 * Normally the first word of the structure is used to hold the list 102 * pointer for free objects. However, when running with diagnostics, 103 * we use the third and fourth fields, so as to catch modifications 104 * in the most commonly trashed first two words. 105 */ 106 struct freelist { 107 long spare0; 108 struct malloc_type *type; 109 long spare1; 110 caddr_t next; 111 }; 112 #else /* !INVARIANTS */ 113 struct freelist { 114 caddr_t next; 115 }; 116 #endif /* INVARIANTS */ 117 118 /* 119 * malloc: 120 * 121 * Allocate a block of memory. 122 * 123 * If M_NOWAIT is set, this routine will not block and return NULL if 124 * the allocation fails. 125 */ 126 void * 127 malloc(size, type, flags) 128 unsigned long size; 129 struct malloc_type *type; 130 int flags; 131 { 132 register struct kmembuckets *kbp; 133 register struct kmemusage *kup; 134 register struct freelist *freep; 135 long indx, npg, allocsize; 136 int s; 137 caddr_t va, cp, savedlist; 138 #ifdef INVARIANTS 139 long *end, *lp; 140 int copysize; 141 const char *savedtype; 142 #endif 143 register struct malloc_type *ksp = type; 144 145 #if defined(INVARIANTS) 146 if (flags == M_WAITOK) 147 KASSERT(curthread->td_intr_nesting_level == 0, 148 ("malloc(M_WAITOK) in interrupt context")); 149 #endif 150 indx = BUCKETINDX(size); 151 kbp = &bucket[indx]; 152 s = splmem(); 153 mtx_lock(&malloc_mtx); 154 while (ksp->ks_memuse >= ksp->ks_limit) { 155 if (flags & M_NOWAIT) { 156 splx(s); 157 mtx_unlock(&malloc_mtx); 158 return ((void *) NULL); 159 } 160 if (ksp->ks_limblocks < 65535) 161 ksp->ks_limblocks++; 162 msleep((caddr_t)ksp, &malloc_mtx, PSWP+2, type->ks_shortdesc, 163 0); 164 } 165 ksp->ks_size |= 1 << indx; 166 #ifdef INVARIANTS 167 copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY; 168 #endif 169 if (kbp->kb_next == NULL) { 170 kbp->kb_last = NULL; 171 if (size > MAXALLOCSAVE) 172 allocsize = roundup(size, PAGE_SIZE); 173 else 174 allocsize = 1 << indx; 175 npg = btoc(allocsize); 176 177 mtx_unlock(&malloc_mtx); 178 va = (caddr_t) kmem_malloc(kmem_map, (vm_size_t)ctob(npg), flags); 179 180 if (va == NULL) { 181 splx(s); 182 return ((void *) NULL); 183 } 184 /* 185 * Enter malloc_mtx after the error check to avoid having to 186 * immediately exit it again if there is an error. 187 */ 188 mtx_lock(&malloc_mtx); 189 190 kbp->kb_total += kbp->kb_elmpercl; 191 kup = btokup(va); 192 kup->ku_indx = indx; 193 if (allocsize > MAXALLOCSAVE) { 194 if (npg > 65535) 195 panic("malloc: allocation too large"); 196 kup->ku_pagecnt = npg; 197 ksp->ks_memuse += allocsize; 198 goto out; 199 } 200 kup->ku_freecnt = kbp->kb_elmpercl; 201 kbp->kb_totalfree += kbp->kb_elmpercl; 202 /* 203 * Just in case we blocked while allocating memory, 204 * and someone else also allocated memory for this 205 * bucket, don't assume the list is still empty. 206 */ 207 savedlist = kbp->kb_next; 208 kbp->kb_next = cp = va + (npg * PAGE_SIZE) - allocsize; 209 for (;;) { 210 freep = (struct freelist *)cp; 211 #ifdef INVARIANTS 212 /* 213 * Copy in known text to detect modification 214 * after freeing. 215 */ 216 end = (long *)&cp[copysize]; 217 for (lp = (long *)cp; lp < end; lp++) 218 *lp = WEIRD_ADDR; 219 freep->type = M_FREE; 220 #endif /* INVARIANTS */ 221 if (cp <= va) 222 break; 223 cp -= allocsize; 224 freep->next = cp; 225 } 226 freep->next = savedlist; 227 if (kbp->kb_last == NULL) 228 kbp->kb_last = (caddr_t)freep; 229 } 230 va = kbp->kb_next; 231 kbp->kb_next = ((struct freelist *)va)->next; 232 #ifdef INVARIANTS 233 freep = (struct freelist *)va; 234 savedtype = (const char *) freep->type->ks_shortdesc; 235 freep->type = (struct malloc_type *)WEIRD_ADDR; 236 if ((intptr_t)(void *)&freep->next & 0x2) 237 freep->next = (caddr_t)((WEIRD_ADDR >> 16)|(WEIRD_ADDR << 16)); 238 else 239 freep->next = (caddr_t)WEIRD_ADDR; 240 end = (long *)&va[copysize]; 241 for (lp = (long *)va; lp < end; lp++) { 242 if (*lp == WEIRD_ADDR) 243 continue; 244 printf("%s %ld of object %p size %lu %s %s (0x%lx != 0x%lx)\n", 245 "Data modified on freelist: word", 246 (long)(lp - (long *)va), (void *)va, size, 247 "previous type", savedtype, *lp, (u_long)WEIRD_ADDR); 248 break; 249 } 250 freep->spare0 = 0; 251 #endif /* INVARIANTS */ 252 kup = btokup(va); 253 if (kup->ku_indx != indx) 254 panic("malloc: wrong bucket"); 255 if (kup->ku_freecnt == 0) 256 panic("malloc: lost data"); 257 kup->ku_freecnt--; 258 kbp->kb_totalfree--; 259 ksp->ks_memuse += 1 << indx; 260 out: 261 kbp->kb_calls++; 262 ksp->ks_inuse++; 263 ksp->ks_calls++; 264 if (ksp->ks_memuse > ksp->ks_maxused) 265 ksp->ks_maxused = ksp->ks_memuse; 266 splx(s); 267 mtx_unlock(&malloc_mtx); 268 /* XXX: Do idle pre-zeroing. */ 269 if (va != NULL && (flags & M_ZERO)) 270 bzero(va, size); 271 return ((void *) va); 272 } 273 274 /* 275 * free: 276 * 277 * Free a block of memory allocated by malloc. 278 * 279 * This routine may not block. 280 */ 281 void 282 free(addr, type) 283 void *addr; 284 struct malloc_type *type; 285 { 286 register struct kmembuckets *kbp; 287 register struct kmemusage *kup; 288 register struct freelist *freep; 289 long size; 290 int s; 291 #ifdef INVARIANTS 292 struct freelist *fp; 293 long *end, *lp, alloc, copysize; 294 #endif 295 register struct malloc_type *ksp = type; 296 297 KASSERT(kmembase <= (char *)addr && (char *)addr < kmemlimit, 298 ("free: address %p out of range", (void *)addr)); 299 kup = btokup(addr); 300 size = 1 << kup->ku_indx; 301 kbp = &bucket[kup->ku_indx]; 302 s = splmem(); 303 mtx_lock(&malloc_mtx); 304 #ifdef INVARIANTS 305 /* 306 * Check for returns of data that do not point to the 307 * beginning of the allocation. 308 */ 309 if (size > PAGE_SIZE) 310 alloc = addrmask[BUCKETINDX(PAGE_SIZE)]; 311 else 312 alloc = addrmask[kup->ku_indx]; 313 if (((uintptr_t)(void *)addr & alloc) != 0) 314 panic("free: unaligned addr %p, size %ld, type %s, mask %ld", 315 (void *)addr, size, type->ks_shortdesc, alloc); 316 #endif /* INVARIANTS */ 317 if (size > MAXALLOCSAVE) { 318 mtx_unlock(&malloc_mtx); 319 kmem_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt)); 320 mtx_lock(&malloc_mtx); 321 322 size = kup->ku_pagecnt << PAGE_SHIFT; 323 ksp->ks_memuse -= size; 324 kup->ku_indx = 0; 325 kup->ku_pagecnt = 0; 326 if (ksp->ks_memuse + size >= ksp->ks_limit && 327 ksp->ks_memuse < ksp->ks_limit) 328 wakeup((caddr_t)ksp); 329 ksp->ks_inuse--; 330 kbp->kb_total -= 1; 331 splx(s); 332 mtx_unlock(&malloc_mtx); 333 return; 334 } 335 freep = (struct freelist *)addr; 336 #ifdef INVARIANTS 337 /* 338 * Check for multiple frees. Use a quick check to see if 339 * it looks free before laboriously searching the freelist. 340 */ 341 if (freep->spare0 == WEIRD_ADDR) { 342 fp = (struct freelist *)kbp->kb_next; 343 while (fp) { 344 if (fp->spare0 != WEIRD_ADDR) 345 panic("free: free item %p modified", fp); 346 else if (addr == (caddr_t)fp) 347 panic("free: multiple freed item %p", addr); 348 fp = (struct freelist *)fp->next; 349 } 350 } 351 /* 352 * Copy in known text to detect modification after freeing 353 * and to make it look free. Also, save the type being freed 354 * so we can list likely culprit if modification is detected 355 * when the object is reallocated. 356 */ 357 copysize = size < MAX_COPY ? size : MAX_COPY; 358 end = (long *)&((caddr_t)addr)[copysize]; 359 for (lp = (long *)addr; lp < end; lp++) 360 *lp = WEIRD_ADDR; 361 freep->type = type; 362 #endif /* INVARIANTS */ 363 kup->ku_freecnt++; 364 if (kup->ku_freecnt >= kbp->kb_elmpercl) { 365 if (kup->ku_freecnt > kbp->kb_elmpercl) 366 panic("free: multiple frees"); 367 else if (kbp->kb_totalfree > kbp->kb_highwat) 368 kbp->kb_couldfree++; 369 } 370 kbp->kb_totalfree++; 371 ksp->ks_memuse -= size; 372 if (ksp->ks_memuse + size >= ksp->ks_limit && 373 ksp->ks_memuse < ksp->ks_limit) 374 wakeup((caddr_t)ksp); 375 ksp->ks_inuse--; 376 #ifdef OLD_MALLOC_MEMORY_POLICY 377 if (kbp->kb_next == NULL) 378 kbp->kb_next = addr; 379 else 380 ((struct freelist *)kbp->kb_last)->next = addr; 381 freep->next = NULL; 382 kbp->kb_last = addr; 383 #else 384 /* 385 * Return memory to the head of the queue for quick reuse. This 386 * can improve performance by improving the probability of the 387 * item being in the cache when it is reused. 388 */ 389 if (kbp->kb_next == NULL) { 390 kbp->kb_next = addr; 391 kbp->kb_last = addr; 392 freep->next = NULL; 393 } else { 394 freep->next = kbp->kb_next; 395 kbp->kb_next = addr; 396 } 397 #endif 398 splx(s); 399 mtx_unlock(&malloc_mtx); 400 } 401 402 /* 403 * Initialize the kernel memory allocator 404 */ 405 /* ARGSUSED*/ 406 static void 407 kmeminit(dummy) 408 void *dummy; 409 { 410 register long indx; 411 u_long npg; 412 u_long mem_size; 413 414 #if ((MAXALLOCSAVE & (MAXALLOCSAVE - 1)) != 0) 415 #error "kmeminit: MAXALLOCSAVE not power of 2" 416 #endif 417 #if (MAXALLOCSAVE > MINALLOCSIZE * 32768) 418 #error "kmeminit: MAXALLOCSAVE too big" 419 #endif 420 #if (MAXALLOCSAVE < PAGE_SIZE) 421 #error "kmeminit: MAXALLOCSAVE too small" 422 #endif 423 424 mtx_init(&malloc_mtx, "malloc", MTX_DEF); 425 426 /* 427 * Try to auto-tune the kernel memory size, so that it is 428 * more applicable for a wider range of machine sizes. 429 * On an X86, a VM_KMEM_SIZE_SCALE value of 4 is good, while 430 * a VM_KMEM_SIZE of 12MB is a fair compromise. The 431 * VM_KMEM_SIZE_MAX is dependent on the maximum KVA space 432 * available, and on an X86 with a total KVA space of 256MB, 433 * try to keep VM_KMEM_SIZE_MAX at 80MB or below. 434 * 435 * Note that the kmem_map is also used by the zone allocator, 436 * so make sure that there is enough space. 437 */ 438 vm_kmem_size = VM_KMEM_SIZE; 439 mem_size = cnt.v_page_count * PAGE_SIZE; 440 441 #if defined(VM_KMEM_SIZE_SCALE) 442 if ((mem_size / VM_KMEM_SIZE_SCALE) > vm_kmem_size) 443 vm_kmem_size = mem_size / VM_KMEM_SIZE_SCALE; 444 #endif 445 446 #if defined(VM_KMEM_SIZE_MAX) 447 if (vm_kmem_size >= VM_KMEM_SIZE_MAX) 448 vm_kmem_size = VM_KMEM_SIZE_MAX; 449 #endif 450 451 /* Allow final override from the kernel environment */ 452 TUNABLE_INT_FETCH("kern.vm.kmem.size", &vm_kmem_size); 453 454 /* 455 * Limit kmem virtual size to twice the physical memory. 456 * This allows for kmem map sparseness, but limits the size 457 * to something sane. Be careful to not overflow the 32bit 458 * ints while doing the check. 459 */ 460 if ((vm_kmem_size / 2) > (cnt.v_page_count * PAGE_SIZE)) 461 vm_kmem_size = 2 * cnt.v_page_count * PAGE_SIZE; 462 463 /* 464 * In mbuf_init(), we set up submaps for mbufs and clusters, in which 465 * case we rounddown() (nmbufs * MSIZE) and (nmbclusters * MCLBYTES), 466 * respectively. Mathematically, this means that what we do here may 467 * amount to slightly more address space than we need for the submaps, 468 * but it never hurts to have an extra page in kmem_map. 469 */ 470 npg = (nmbufs * MSIZE + nmbclusters * MCLBYTES + nmbcnt * 471 sizeof(u_int) + vm_kmem_size) / PAGE_SIZE; 472 473 kmemusage = (struct kmemusage *) kmem_alloc(kernel_map, 474 (vm_size_t)(npg * sizeof(struct kmemusage))); 475 kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase, 476 (vm_offset_t *)&kmemlimit, (vm_size_t)(npg * PAGE_SIZE)); 477 kmem_map->system_map = 1; 478 for (indx = 0; indx < MINBUCKET + 16; indx++) { 479 if (1 << indx >= PAGE_SIZE) 480 bucket[indx].kb_elmpercl = 1; 481 else 482 bucket[indx].kb_elmpercl = PAGE_SIZE / (1 << indx); 483 bucket[indx].kb_highwat = 5 * bucket[indx].kb_elmpercl; 484 } 485 } 486 487 void 488 malloc_init(data) 489 void *data; 490 { 491 struct malloc_type *type = (struct malloc_type *)data; 492 493 if (type->ks_magic != M_MAGIC) 494 panic("malloc type lacks magic"); 495 496 if (type->ks_limit != 0) 497 return; 498 499 if (cnt.v_page_count == 0) 500 panic("malloc_init not allowed before vm init"); 501 502 /* 503 * The default limits for each malloc region is 1/2 of the 504 * malloc portion of the kmem map size. 505 */ 506 type->ks_limit = vm_kmem_size / 2; 507 type->ks_next = kmemstatistics; 508 kmemstatistics = type; 509 } 510 511 void 512 malloc_uninit(data) 513 void *data; 514 { 515 struct malloc_type *type = (struct malloc_type *)data; 516 struct malloc_type *t; 517 #ifdef INVARIANTS 518 struct kmembuckets *kbp; 519 struct freelist *freep; 520 long indx; 521 int s; 522 #endif 523 524 if (type->ks_magic != M_MAGIC) 525 panic("malloc type lacks magic"); 526 527 if (cnt.v_page_count == 0) 528 panic("malloc_uninit not allowed before vm init"); 529 530 if (type->ks_limit == 0) 531 panic("malloc_uninit on uninitialized type"); 532 533 #ifdef INVARIANTS 534 s = splmem(); 535 mtx_lock(&malloc_mtx); 536 for (indx = 0; indx < MINBUCKET + 16; indx++) { 537 kbp = bucket + indx; 538 freep = (struct freelist*)kbp->kb_next; 539 while (freep) { 540 if (freep->type == type) 541 freep->type = M_FREE; 542 freep = (struct freelist*)freep->next; 543 } 544 } 545 splx(s); 546 mtx_unlock(&malloc_mtx); 547 548 if (type->ks_memuse != 0) 549 printf("malloc_uninit: %ld bytes of '%s' still allocated\n", 550 type->ks_memuse, type->ks_shortdesc); 551 #endif 552 553 if (type == kmemstatistics) 554 kmemstatistics = type->ks_next; 555 else { 556 for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) { 557 if (t->ks_next == type) { 558 t->ks_next = type->ks_next; 559 break; 560 } 561 } 562 } 563 type->ks_next = NULL; 564 type->ks_limit = 0; 565 } 566