kern_malloc.c revision 1.32
1 /* $NetBSD: kern_malloc.c,v 1.32 1998/03/01 02:22:29 fvdl Exp $ */ 2 3 /* 4 * Copyright 1996 Christopher G. Demetriou. All rights reserved. 5 * Copyright (c) 1987, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)kern_malloc.c 8.4 (Berkeley) 5/20/95 37 */ 38 39 #include "opt_uvm.h" 40 41 #include <sys/param.h> 42 #include <sys/proc.h> 43 #include <sys/map.h> 44 #include <sys/kernel.h> 45 #include <sys/malloc.h> 46 #include <sys/systm.h> 47 48 #include <vm/vm.h> 49 #include <vm/vm_kern.h> 50 51 #if defined(UVM) 52 #include <uvm/uvm_extern.h> 53 54 static struct vm_map kmem_map_store; 55 vm_map_t kmem_map = NULL; 56 #endif 57 58 #include "opt_kmemstats.h" 59 #include "opt_malloclog.h" 60 61 struct kmembuckets bucket[MINBUCKET + 16]; 62 struct kmemstats kmemstats[M_LAST]; 63 struct kmemusage *kmemusage; 64 char *kmembase, *kmemlimit; 65 const char *memname[] = INITKMEMNAMES; 66 67 #ifdef MALLOCLOG 68 #ifndef MALLOCLOGSIZE 69 #define MALLOCLOGSIZE 100000 70 #endif 71 72 struct malloclog { 73 void *addr; 74 long size; 75 int type; 76 int action; 77 const char *file; 78 long line; 79 } malloclog[MALLOCLOGSIZE]; 80 81 long malloclogptr; 82 83 static void domlog __P((void *a, long size, int type, int action, 84 const char *file, long line)); 85 static void hitmlog __P((void *a)); 86 87 static void 88 domlog(a, size, type, action, file, line) 89 void *a; 90 long size; 91 int type; 92 int action; 93 const char *file; 94 long line; 95 { 96 97 malloclog[malloclogptr].addr = a; 98 malloclog[malloclogptr].size = size; 99 malloclog[malloclogptr].type = type; 100 malloclog[malloclogptr].action = action; 101 malloclog[malloclogptr].file = file; 102 malloclog[malloclogptr].line = line; 103 malloclogptr++; 104 if (malloclogptr >= MALLOCLOGSIZE) 105 malloclogptr = 0; 106 } 107 108 static void 109 hitmlog(a) 110 void *a; 111 { 112 struct malloclog *lp; 113 long l; 114 115 #define PRT \ 116 if (malloclog[l].addr == a && malloclog[l].action) { \ 117 lp = &malloclog[l]; \ 118 printf("malloc log entry %ld:\n", l); \ 119 printf("\taddr = %p\n", lp->addr); \ 120 printf("\tsize = %ld\n", lp->size); \ 121 printf("\ttype = %s\n", memname[lp->type]); \ 122 printf("\taction = %s\n", lp->action == 1 ? "alloc" : "free"); \ 123 printf("\tfile = %s\n", lp->file); \ 124 printf("\tline = %ld\n", lp->line); \ 125 } 126 127 for (l = malloclogptr; l < MALLOCLOGSIZE; l++) 128 PRT 129 130 for (l = 0; l < malloclogptr; l++) 131 PRT 132 } 133 #endif /* MALLOCLOG */ 134 135 #ifdef DIAGNOSTIC 136 /* 137 * This structure provides a set of masks to catch unaligned frees. 138 */ 139 long addrmask[] = { 0, 140 0x00000001, 0x00000003, 0x00000007, 0x0000000f, 141 0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff, 142 0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff, 143 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff, 144 }; 145 146 /* 147 * The WEIRD_ADDR is used as known text to copy into free objects so 148 * that modifications after frees can be detected. 149 */ 150 #define WEIRD_ADDR ((unsigned) 0xdeadbeef) 151 #define MAX_COPY 32 152 153 /* 154 * Normally the freelist structure is used only to hold the list pointer 155 * for free objects. However, when running with diagnostics, the first 156 * 8 bytes of the structure is unused except for diagnostic information, 157 * and the free list pointer is at offst 8 in the structure. Since the 158 * first 8 bytes is the portion of the structure most often modified, this 159 * helps to detect memory reuse problems and avoid free list corruption. 160 */ 161 struct freelist { 162 int32_t spare0; 163 int16_t type; 164 int16_t spare1; 165 caddr_t next; 166 }; 167 #else /* !DIAGNOSTIC */ 168 struct freelist { 169 caddr_t next; 170 }; 171 #endif /* DIAGNOSTIC */ 172 173 /* 174 * Allocate a block of memory 175 */ 176 #ifdef MALLOCLOG 177 void * 178 _malloc(size, type, flags, file, line) 179 unsigned long size; 180 int type, flags; 181 const char *file; 182 long line; 183 #else 184 void * 185 malloc(size, type, flags) 186 unsigned long size; 187 int type, flags; 188 #endif /* MALLOCLOG */ 189 { 190 register struct kmembuckets *kbp; 191 register struct kmemusage *kup; 192 register struct freelist *freep; 193 long indx, npg, allocsize; 194 int s; 195 caddr_t va, cp, savedlist; 196 #ifdef DIAGNOSTIC 197 int32_t *end, *lp; 198 int copysize; 199 const char *savedtype; 200 #endif 201 #ifdef LOCKDEBUG 202 extern int simplelockrecurse; 203 #endif 204 #ifdef KMEMSTATS 205 register struct kmemstats *ksp = &kmemstats[type]; 206 207 if (((unsigned long)type) > M_LAST) 208 panic("malloc - bogus type"); 209 #endif 210 indx = BUCKETINDX(size); 211 kbp = &bucket[indx]; 212 s = splimp(); 213 #ifdef KMEMSTATS 214 while (ksp->ks_memuse >= ksp->ks_limit) { 215 if (flags & M_NOWAIT) { 216 splx(s); 217 return ((void *) NULL); 218 } 219 if (ksp->ks_limblocks < 65535) 220 ksp->ks_limblocks++; 221 tsleep((caddr_t)ksp, PSWP+2, memname[type], 0); 222 } 223 ksp->ks_size |= 1 << indx; 224 #endif 225 #ifdef DIAGNOSTIC 226 copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY; 227 #endif 228 #ifdef LOCKDEBUG 229 if (flags & M_NOWAIT) 230 simplelockrecurse++; 231 #endif 232 if (kbp->kb_next == NULL) { 233 kbp->kb_last = NULL; 234 if (size > MAXALLOCSAVE) 235 allocsize = roundup(size, CLBYTES); 236 else 237 allocsize = 1 << indx; 238 npg = clrnd(btoc(allocsize)); 239 #if defined(UVM) 240 va = (caddr_t) uvm_km_kmemalloc(kmem_map, uvmexp.kmem_object, 241 (vm_size_t)ctob(npg), 242 (flags & M_NOWAIT) ? UVM_KMF_NOWAIT : 0); 243 #else 244 va = (caddr_t) kmem_malloc(kmem_map, (vm_size_t)ctob(npg), 245 !(flags & M_NOWAIT)); 246 #endif 247 if (va == NULL) { 248 /* 249 * Kmem_malloc() can return NULL, even if it can 250 * wait, if there is no map space avaiable, because 251 * it can't fix that problem. Neither can we, 252 * right now. (We should release pages which 253 * are completely free and which are in buckets 254 * with too many free elements.) 255 */ 256 if ((flags & M_NOWAIT) == 0) 257 panic("malloc: out of space in kmem_map"); 258 #ifdef LOCKDEBUG 259 simplelockrecurse--; 260 #endif 261 splx(s); 262 return ((void *) NULL); 263 } 264 #ifdef KMEMSTATS 265 kbp->kb_total += kbp->kb_elmpercl; 266 #endif 267 kup = btokup(va); 268 kup->ku_indx = indx; 269 if (allocsize > MAXALLOCSAVE) { 270 if (npg > 65535) 271 panic("malloc: allocation too large"); 272 kup->ku_pagecnt = npg; 273 #ifdef KMEMSTATS 274 ksp->ks_memuse += allocsize; 275 #endif 276 goto out; 277 } 278 #ifdef KMEMSTATS 279 kup->ku_freecnt = kbp->kb_elmpercl; 280 kbp->kb_totalfree += kbp->kb_elmpercl; 281 #endif 282 /* 283 * Just in case we blocked while allocating memory, 284 * and someone else also allocated memory for this 285 * bucket, don't assume the list is still empty. 286 */ 287 savedlist = kbp->kb_next; 288 kbp->kb_next = cp = va + (npg * NBPG) - allocsize; 289 for (;;) { 290 freep = (struct freelist *)cp; 291 #ifdef DIAGNOSTIC 292 /* 293 * Copy in known text to detect modification 294 * after freeing. 295 */ 296 end = (int32_t *)&cp[copysize]; 297 for (lp = (int32_t *)cp; lp < end; lp++) 298 *lp = WEIRD_ADDR; 299 freep->type = M_FREE; 300 #endif /* DIAGNOSTIC */ 301 if (cp <= va) 302 break; 303 cp -= allocsize; 304 freep->next = cp; 305 } 306 freep->next = savedlist; 307 if (kbp->kb_last == NULL) 308 kbp->kb_last = (caddr_t)freep; 309 } 310 va = kbp->kb_next; 311 kbp->kb_next = ((struct freelist *)va)->next; 312 #ifdef DIAGNOSTIC 313 freep = (struct freelist *)va; 314 savedtype = (unsigned)freep->type < M_LAST ? 315 memname[freep->type] : "???"; 316 #if defined(UVM) 317 if (kbp->kb_next) { 318 int rv; 319 vm_offset_t addr = (vm_offset_t)kbp->kb_next; 320 321 vm_map_lock_read(kmem_map); 322 rv = uvm_map_checkprot(kmem_map, addr, 323 addr + sizeof(struct freelist), 324 VM_PROT_WRITE); 325 vm_map_unlock_read(kmem_map); 326 327 if (!rv) 328 #else 329 if (kbp->kb_next && 330 !kernacc(kbp->kb_next, sizeof(struct freelist), 0)) 331 #endif 332 { 333 printf( 334 "%s %ld of object %p size %ld %s %s (invalid addr %p)\n", 335 "Data modified on freelist: word", 336 (long)((int32_t *)&kbp->kb_next - (int32_t *)kbp), 337 va, size, "previous type", savedtype, kbp->kb_next); 338 #ifdef MALLOCLOG 339 hitmlog(va); 340 #endif 341 kbp->kb_next = NULL; 342 #if defined(UVM) 343 } 344 #endif 345 } 346 347 /* Fill the fields that we've used with WEIRD_ADDR */ 348 #if BYTE_ORDER == BIG_ENDIAN 349 freep->type = WEIRD_ADDR >> 16; 350 #endif 351 #if BYTE_ORDER == LITTLE_ENDIAN 352 freep->type = (short)WEIRD_ADDR; 353 #endif 354 end = (int32_t *)&freep->next + 355 (sizeof(freep->next) / sizeof(int32_t)); 356 for (lp = (int32_t *)&freep->next; lp < end; lp++) 357 *lp = WEIRD_ADDR; 358 359 /* and check that the data hasn't been modified. */ 360 end = (int32_t *)&va[copysize]; 361 for (lp = (int32_t *)va; lp < end; lp++) { 362 if (*lp == WEIRD_ADDR) 363 continue; 364 printf("%s %ld of object %p size %ld %s %s (0x%x != 0x%x)\n", 365 "Data modified on freelist: word", 366 (long)(lp - (int32_t *)va), va, size, "previous type", 367 savedtype, *lp, WEIRD_ADDR); 368 #ifdef MALLOCLOG 369 hitmlog(va); 370 #endif 371 break; 372 } 373 374 freep->spare0 = 0; 375 #endif /* DIAGNOSTIC */ 376 #ifdef KMEMSTATS 377 kup = btokup(va); 378 if (kup->ku_indx != indx) 379 panic("malloc: wrong bucket"); 380 if (kup->ku_freecnt == 0) 381 panic("malloc: lost data"); 382 kup->ku_freecnt--; 383 kbp->kb_totalfree--; 384 ksp->ks_memuse += 1 << indx; 385 out: 386 kbp->kb_calls++; 387 ksp->ks_inuse++; 388 ksp->ks_calls++; 389 if (ksp->ks_memuse > ksp->ks_maxused) 390 ksp->ks_maxused = ksp->ks_memuse; 391 #else 392 out: 393 #endif 394 #ifdef MALLOCLOG 395 domlog(va, size, type, 1, file, line); 396 #endif 397 splx(s); 398 #ifdef LOCKDEBUG 399 if (flags & M_NOWAIT) 400 simplelockrecurse--; 401 #endif 402 return ((void *) va); 403 } 404 405 /* 406 * Free a block of memory allocated by malloc. 407 */ 408 #ifdef MALLOCLOG 409 void 410 _free(addr, type, file, line) 411 void *addr; 412 int type; 413 const char *file; 414 long line; 415 #else 416 void 417 free(addr, type) 418 void *addr; 419 int type; 420 #endif /* MALLOCLOG */ 421 { 422 register struct kmembuckets *kbp; 423 register struct kmemusage *kup; 424 register struct freelist *freep; 425 long size; 426 int s; 427 #ifdef DIAGNOSTIC 428 caddr_t cp; 429 int32_t *end, *lp; 430 long alloc, copysize; 431 #endif 432 #ifdef KMEMSTATS 433 register struct kmemstats *ksp = &kmemstats[type]; 434 #endif 435 436 kup = btokup(addr); 437 size = 1 << kup->ku_indx; 438 kbp = &bucket[kup->ku_indx]; 439 s = splimp(); 440 #ifdef MALLOCLOG 441 domlog(addr, 0, type, 2, file, line); 442 #endif 443 #ifdef DIAGNOSTIC 444 /* 445 * Check for returns of data that do not point to the 446 * beginning of the allocation. 447 */ 448 if (size > NBPG * CLSIZE) 449 alloc = addrmask[BUCKETINDX(NBPG * CLSIZE)]; 450 else 451 alloc = addrmask[kup->ku_indx]; 452 if (((u_long)addr & alloc) != 0) 453 panic("free: unaligned addr %p, size %ld, type %s, mask %ld\n", 454 addr, size, memname[type], alloc); 455 #endif /* DIAGNOSTIC */ 456 if (size > MAXALLOCSAVE) { 457 #if defined(UVM) 458 uvm_km_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt)); 459 #else 460 kmem_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt)); 461 #endif 462 #ifdef KMEMSTATS 463 size = kup->ku_pagecnt << PGSHIFT; 464 ksp->ks_memuse -= size; 465 kup->ku_indx = 0; 466 kup->ku_pagecnt = 0; 467 if (ksp->ks_memuse + size >= ksp->ks_limit && 468 ksp->ks_memuse < ksp->ks_limit) 469 wakeup((caddr_t)ksp); 470 ksp->ks_inuse--; 471 kbp->kb_total -= 1; 472 #endif 473 splx(s); 474 return; 475 } 476 freep = (struct freelist *)addr; 477 #ifdef DIAGNOSTIC 478 /* 479 * Check for multiple frees. Use a quick check to see if 480 * it looks free before laboriously searching the freelist. 481 */ 482 if (freep->spare0 == WEIRD_ADDR) { 483 for (cp = kbp->kb_next; cp; 484 cp = ((struct freelist *)cp)->next) { 485 if (addr != cp) 486 continue; 487 printf("multiply freed item %p\n", addr); 488 #ifdef MALLOCLOG 489 hitmlog(addr); 490 #endif 491 panic("free: duplicated free"); 492 } 493 } 494 /* 495 * Copy in known text to detect modification after freeing 496 * and to make it look free. Also, save the type being freed 497 * so we can list likely culprit if modification is detected 498 * when the object is reallocated. 499 */ 500 copysize = size < MAX_COPY ? size : MAX_COPY; 501 end = (int32_t *)&((caddr_t)addr)[copysize]; 502 for (lp = (int32_t *)addr; lp < end; lp++) 503 *lp = WEIRD_ADDR; 504 freep->type = type; 505 #endif /* DIAGNOSTIC */ 506 #ifdef KMEMSTATS 507 kup->ku_freecnt++; 508 if (kup->ku_freecnt >= kbp->kb_elmpercl) 509 if (kup->ku_freecnt > kbp->kb_elmpercl) 510 panic("free: multiple frees"); 511 else if (kbp->kb_totalfree > kbp->kb_highwat) 512 kbp->kb_couldfree++; 513 kbp->kb_totalfree++; 514 ksp->ks_memuse -= size; 515 if (ksp->ks_memuse + size >= ksp->ks_limit && 516 ksp->ks_memuse < ksp->ks_limit) 517 wakeup((caddr_t)ksp); 518 ksp->ks_inuse--; 519 #endif 520 if (kbp->kb_next == NULL) 521 kbp->kb_next = addr; 522 else 523 ((struct freelist *)kbp->kb_last)->next = addr; 524 freep->next = NULL; 525 kbp->kb_last = addr; 526 splx(s); 527 } 528 529 /* 530 * Change the size of a block of memory. 531 */ 532 void * 533 realloc(curaddr, newsize, type, flags) 534 void *curaddr; 535 unsigned long newsize; 536 int type, flags; 537 { 538 register struct kmemusage *kup; 539 long cursize; 540 void *newaddr; 541 #ifdef DIAGNOSTIC 542 long alloc; 543 #endif 544 545 /* 546 * Realloc() with a NULL pointer is the same as malloc(). 547 */ 548 if (curaddr == NULL) 549 return (malloc(newsize, type, flags)); 550 551 /* 552 * Realloc() with zero size is the same as free(). 553 */ 554 if (newsize == 0) { 555 free(curaddr, type); 556 return (NULL); 557 } 558 559 /* 560 * Find out how large the old allocation was (and do some 561 * sanity checking). 562 */ 563 kup = btokup(curaddr); 564 cursize = 1 << kup->ku_indx; 565 566 #ifdef DIAGNOSTIC 567 /* 568 * Check for returns of data that do not point to the 569 * beginning of the allocation. 570 */ 571 if (cursize > NBPG * CLSIZE) 572 alloc = addrmask[BUCKETINDX(NBPG * CLSIZE)]; 573 else 574 alloc = addrmask[kup->ku_indx]; 575 if (((u_long)curaddr & alloc) != 0) 576 panic("realloc: unaligned addr %p, size %ld, type %s, mask %ld\n", 577 curaddr, cursize, memname[type], alloc); 578 #endif /* DIAGNOSTIC */ 579 580 if (cursize > MAXALLOCSAVE) 581 cursize = ctob(kup->ku_pagecnt); 582 583 /* 584 * If we already actually have as much as they want, we're done. 585 */ 586 if (newsize <= cursize) 587 return (curaddr); 588 589 /* 590 * Can't satisfy the allocation with the existing block. 591 * Allocate a new one and copy the data. 592 */ 593 newaddr = malloc(newsize, type, flags); 594 if (newaddr == NULL) { 595 /* 596 * Malloc() failed, because flags included M_NOWAIT. 597 * Return NULL to indicate that failure. The old 598 * pointer is still valid. 599 */ 600 return NULL; 601 } 602 bcopy(curaddr, newaddr, cursize); 603 604 /* 605 * We were successful: free the old allocation and return 606 * the new one. 607 */ 608 free(curaddr, type); 609 return (newaddr); 610 } 611 612 /* 613 * Initialize the kernel memory allocator 614 */ 615 void 616 kmeminit() 617 { 618 #ifdef KMEMSTATS 619 register long indx; 620 #endif 621 int npg; 622 623 #if ((MAXALLOCSAVE & (MAXALLOCSAVE - 1)) != 0) 624 ERROR!_kmeminit:_MAXALLOCSAVE_not_power_of_2 625 #endif 626 #if (MAXALLOCSAVE > MINALLOCSIZE * 32768) 627 ERROR!_kmeminit:_MAXALLOCSAVE_too_big 628 #endif 629 #if (MAXALLOCSAVE < CLBYTES) 630 ERROR!_kmeminit:_MAXALLOCSAVE_too_small 631 #endif 632 633 if (sizeof(struct freelist) > (1 << MINBUCKET)) 634 panic("minbucket too small/struct freelist too big"); 635 636 npg = VM_KMEM_SIZE/ NBPG; 637 #if defined(UVM) 638 kmemusage = (struct kmemusage *) uvm_km_zalloc(kernel_map, 639 (vm_size_t)(npg * sizeof(struct kmemusage))); 640 kmem_map = uvm_km_suballoc(kernel_map, (vm_offset_t *)&kmembase, 641 (vm_offset_t *)&kmemlimit, (vm_size_t)(npg * NBPG), 642 FALSE, FALSE, &kmem_map_store); 643 #else 644 kmemusage = (struct kmemusage *) kmem_alloc(kernel_map, 645 (vm_size_t)(npg * sizeof(struct kmemusage))); 646 kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase, 647 (vm_offset_t *)&kmemlimit, (vm_size_t)(npg * NBPG), FALSE); 648 #endif 649 #ifdef KMEMSTATS 650 for (indx = 0; indx < MINBUCKET + 16; indx++) { 651 if (1 << indx >= CLBYTES) 652 bucket[indx].kb_elmpercl = 1; 653 else 654 bucket[indx].kb_elmpercl = CLBYTES / (1 << indx); 655 bucket[indx].kb_highwat = 5 * bucket[indx].kb_elmpercl; 656 } 657 for (indx = 0; indx < M_LAST; indx++) 658 kmemstats[indx].ks_limit = npg * NBPG * 6 / 10; 659 #endif 660 } 661
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