1 /*- 2 * Copyright (c) 1987, 1991, 1993 3 * The Regents of the University of California. 4 * Copyright (c) 2005-2009 Robert N. M. Watson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 4. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)kern_malloc.c 8.3 (Berkeley) 1/4/94 32 */ 33 34 /* 35 * Kernel malloc(9) implementation -- general purpose kernel memory allocator 36 * based on memory types. Back end is implemented using the UMA(9) zone 37 * allocator. A set of fixed-size buckets are used for smaller allocations, 38 * and a special UMA allocation interface is used for larger allocations. 39 * Callers declare memory types, and statistics are maintained independently 40 * for each memory type. Statistics are maintained per-CPU for performance 41 * reasons. See malloc(9) and comments in malloc.h for a detailed 42 * description. 43 */ 44 45 #include <sys/cdefs.h> 46 __FBSDID("$FreeBSD$"); 47 48 #include "opt_ddb.h" 49 #include "opt_kdtrace.h" 50 #include "opt_vm.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/kdb.h> 55 #include <sys/kernel.h> 56 #include <sys/lock.h> 57 #include <sys/malloc.h> 58 #include <sys/mbuf.h> 59 #include <sys/mutex.h> 60 #include <sys/vmmeter.h> 61 #include <sys/proc.h> 62 #include <sys/sbuf.h> 63 #include <sys/sysctl.h> 64 #include <sys/time.h> 65 66 #include <vm/vm.h> 67 #include <vm/pmap.h> 68 #include <vm/vm_param.h> 69 #include <vm/vm_kern.h> 70 #include <vm/vm_extern.h> 71 #include <vm/vm_map.h> 72 #include <vm/vm_page.h> 73 #include <vm/uma.h> 74 #include <vm/uma_int.h> 75 #include <vm/uma_dbg.h> 76 77 #ifdef DEBUG_MEMGUARD 78 #include <vm/memguard.h> 79 #endif 80 #ifdef DEBUG_REDZONE 81 #include <vm/redzone.h> 82 #endif 83 84 #if defined(INVARIANTS) && defined(__i386__) 85 #include <machine/cpu.h> 86 #endif 87 88 #include <ddb/ddb.h> 89 90 #ifdef KDTRACE_HOOKS 91 #include <sys/dtrace_bsd.h> 92 93 dtrace_malloc_probe_func_t dtrace_malloc_probe; 94 #endif 95 96 /* 97 * When realloc() is called, if the new size is sufficiently smaller than 98 * the old size, realloc() will allocate a new, smaller block to avoid 99 * wasting memory. 'Sufficiently smaller' is defined as: newsize <= 100 * oldsize / 2^n, where REALLOC_FRACTION defines the value of 'n'. 101 */ 102 #ifndef REALLOC_FRACTION 103 #define REALLOC_FRACTION 1 /* new block if <= half the size */ 104 #endif 105 106 /* 107 * Centrally define some common malloc types. 108 */ 109 MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches"); 110 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); 111 MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers"); 112 113 MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options"); 114 MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery"); 115 116 static void kmeminit(void *); 117 SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, kmeminit, NULL); 118 119 static MALLOC_DEFINE(M_FREE, "free", "should be on free list"); 120 121 static struct malloc_type *kmemstatistics; 122 static vm_offset_t kmembase; 123 static vm_offset_t kmemlimit; 124 static int kmemcount; 125 126 #define KMEM_ZSHIFT 4 127 #define KMEM_ZBASE 16 128 #define KMEM_ZMASK (KMEM_ZBASE - 1) 129 130 #define KMEM_ZMAX PAGE_SIZE 131 #define KMEM_ZSIZE (KMEM_ZMAX >> KMEM_ZSHIFT) 132 static uint8_t kmemsize[KMEM_ZSIZE + 1]; 133 134 #ifndef MALLOC_DEBUG_MAXZONES 135 #define MALLOC_DEBUG_MAXZONES 1 136 #endif 137 static int numzones = MALLOC_DEBUG_MAXZONES; 138 139 /* 140 * Small malloc(9) memory allocations are allocated from a set of UMA buckets 141 * of various sizes. 142 * 143 * XXX: The comment here used to read "These won't be powers of two for 144 * long." It's possible that a significant amount of wasted memory could be 145 * recovered by tuning the sizes of these buckets. 146 */ 147 struct { 148 int kz_size; 149 char *kz_name; 150 uma_zone_t kz_zone[MALLOC_DEBUG_MAXZONES]; 151 } kmemzones[] = { 152 {16, "16", }, 153 {32, "32", }, 154 {64, "64", }, 155 {128, "128", }, 156 {256, "256", }, 157 {512, "512", }, 158 {1024, "1024", }, 159 {2048, "2048", }, 160 {4096, "4096", }, 161 #if PAGE_SIZE > 4096 162 {8192, "8192", }, 163 #if PAGE_SIZE > 8192 164 {16384, "16384", }, 165 #if PAGE_SIZE > 16384 166 {32768, "32768", }, 167 #if PAGE_SIZE > 32768 168 {65536, "65536", }, 169 #if PAGE_SIZE > 65536 170 #error "Unsupported PAGE_SIZE" 171 #endif /* 65536 */ 172 #endif /* 32768 */ 173 #endif /* 16384 */ 174 #endif /* 8192 */ 175 #endif /* 4096 */ 176 {0, NULL}, 177 }; 178 179 /* 180 * Zone to allocate malloc type descriptions from. For ABI reasons, memory 181 * types are described by a data structure passed by the declaring code, but 182 * the malloc(9) implementation has its own data structure describing the 183 * type and statistics. This permits the malloc(9)-internal data structures 184 * to be modified without breaking binary-compiled kernel modules that 185 * declare malloc types. 186 */ 187 static uma_zone_t mt_zone; 188 189 static u_long vm_min_kernel_address = VM_MIN_KERNEL_ADDRESS; 190 SYSCTL_ULONG(_vm, OID_AUTO, min_kernel_address, CTLFLAG_RD, 191 &vm_min_kernel_address, 0, "Min kernel address"); 192 193 static u_long vm_max_kernel_address = VM_MAX_KERNEL_ADDRESS; 194 SYSCTL_ULONG(_vm, OID_AUTO, max_kernel_address, CTLFLAG_RD, 195 &vm_max_kernel_address, 0, "Max kernel address"); 196 197 u_long vm_kmem_size; 198 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size, CTLFLAG_RDTUN, &vm_kmem_size, 0, 199 "Size of kernel memory"); 200 201 static u_long vm_kmem_size_min; 202 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_min, CTLFLAG_RDTUN, &vm_kmem_size_min, 0, 203 "Minimum size of kernel memory"); 204 205 static u_long vm_kmem_size_max; 206 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RDTUN, &vm_kmem_size_max, 0, 207 "Maximum size of kernel memory"); 208 209 static u_int vm_kmem_size_scale; 210 SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RDTUN, &vm_kmem_size_scale, 0, 211 "Scale factor for kernel memory size"); 212 213 static int sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS); 214 SYSCTL_PROC(_vm, OID_AUTO, kmem_map_size, 215 CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, 216 sysctl_kmem_map_size, "LU", "Current kmem_map allocation size"); 217 218 static int sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS); 219 SYSCTL_PROC(_vm, OID_AUTO, kmem_map_free, 220 CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, 221 sysctl_kmem_map_free, "LU", "Largest contiguous free range in kmem_map"); 222 223 /* 224 * The malloc_mtx protects the kmemstatistics linked list. 225 */ 226 struct mtx malloc_mtx; 227 228 #ifdef MALLOC_PROFILE 229 uint64_t krequests[KMEM_ZSIZE + 1]; 230 231 static int sysctl_kern_mprof(SYSCTL_HANDLER_ARGS); 232 #endif 233 234 static int sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS); 235 236 /* 237 * time_uptime of the last malloc(9) failure (induced or real). 238 */ 239 static time_t t_malloc_fail; 240 241 #if defined(MALLOC_MAKE_FAILURES) || (MALLOC_DEBUG_MAXZONES > 1) 242 static SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD, 0, 243 "Kernel malloc debugging options"); 244 #endif 245 246 /* 247 * malloc(9) fault injection -- cause malloc failures every (n) mallocs when 248 * the caller specifies M_NOWAIT. If set to 0, no failures are caused. 249 */ 250 #ifdef MALLOC_MAKE_FAILURES 251 static int malloc_failure_rate; 252 static int malloc_nowait_count; 253 static int malloc_failure_count; 254 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RW, 255 &malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail"); 256 TUNABLE_INT("debug.malloc.failure_rate", &malloc_failure_rate); 257 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD, 258 &malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures"); 259 #endif 260 261 static int 262 sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS) 263 { 264 u_long size; 265 266 size = kmem_map->size; 267 return (sysctl_handle_long(oidp, &size, 0, req)); 268 } 269 270 static int 271 sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS) 272 { 273 u_long size; 274 275 vm_map_lock_read(kmem_map); 276 size = kmem_map->root != NULL ? kmem_map->root->max_free : 277 kmem_map->max_offset - kmem_map->min_offset; 278 vm_map_unlock_read(kmem_map); 279 return (sysctl_handle_long(oidp, &size, 0, req)); 280 } 281 282 /* 283 * malloc(9) uma zone separation -- sub-page buffer overruns in one 284 * malloc type will affect only a subset of other malloc types. 285 */ 286 #if MALLOC_DEBUG_MAXZONES > 1 287 static void 288 tunable_set_numzones(void) 289 { 290 291 TUNABLE_INT_FETCH("debug.malloc.numzones", 292 &numzones); 293 294 /* Sanity check the number of malloc uma zones. */ 295 if (numzones <= 0) 296 numzones = 1; 297 if (numzones > MALLOC_DEBUG_MAXZONES) 298 numzones = MALLOC_DEBUG_MAXZONES; 299 } 300 SYSINIT(numzones, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_set_numzones, NULL); 301 SYSCTL_INT(_debug_malloc, OID_AUTO, numzones, CTLFLAG_RDTUN, 302 &numzones, 0, "Number of malloc uma subzones"); 303 304 /* 305 * Any number that changes regularly is an okay choice for the 306 * offset. Build numbers are pretty good of you have them. 307 */ 308 static u_int zone_offset = __FreeBSD_version; 309 TUNABLE_INT("debug.malloc.zone_offset", &zone_offset); 310 SYSCTL_UINT(_debug_malloc, OID_AUTO, zone_offset, CTLFLAG_RDTUN, 311 &zone_offset, 0, "Separate malloc types by examining the " 312 "Nth character in the malloc type short description."); 313 314 static u_int 315 mtp_get_subzone(const char *desc) 316 { 317 size_t len; 318 u_int val; 319 320 if (desc == NULL || (len = strlen(desc)) == 0) 321 return (0); 322 val = desc[zone_offset % len]; 323 return (val % numzones); 324 } 325 #elif MALLOC_DEBUG_MAXZONES == 0 326 #error "MALLOC_DEBUG_MAXZONES must be positive." 327 #else 328 static inline u_int 329 mtp_get_subzone(const char *desc) 330 { 331 332 return (0); 333 } 334 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 335 336 int 337 malloc_last_fail(void) 338 { 339 340 return (time_uptime - t_malloc_fail); 341 } 342 343 /* 344 * An allocation has succeeded -- update malloc type statistics for the 345 * amount of bucket size. Occurs within a critical section so that the 346 * thread isn't preempted and doesn't migrate while updating per-PCU 347 * statistics. 348 */ 349 static void 350 malloc_type_zone_allocated(struct malloc_type *mtp, unsigned long size, 351 int zindx) 352 { 353 struct malloc_type_internal *mtip; 354 struct malloc_type_stats *mtsp; 355 356 critical_enter(); 357 mtip = mtp->ks_handle; 358 mtsp = &mtip->mti_stats[curcpu]; 359 if (size > 0) { 360 mtsp->mts_memalloced += size; 361 mtsp->mts_numallocs++; 362 } 363 if (zindx != -1) 364 mtsp->mts_size |= 1 << zindx; 365 366 #ifdef KDTRACE_HOOKS 367 if (dtrace_malloc_probe != NULL) { 368 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_MALLOC]; 369 if (probe_id != 0) 370 (dtrace_malloc_probe)(probe_id, 371 (uintptr_t) mtp, (uintptr_t) mtip, 372 (uintptr_t) mtsp, size, zindx); 373 } 374 #endif 375 376 critical_exit(); 377 } 378 379 void 380 malloc_type_allocated(struct malloc_type *mtp, unsigned long size) 381 { 382 383 if (size > 0) 384 malloc_type_zone_allocated(mtp, size, -1); 385 } 386 387 /* 388 * A free operation has occurred -- update malloc type statistics for the 389 * amount of the bucket size. Occurs within a critical section so that the 390 * thread isn't preempted and doesn't migrate while updating per-CPU 391 * statistics. 392 */ 393 void 394 malloc_type_freed(struct malloc_type *mtp, unsigned long size) 395 { 396 struct malloc_type_internal *mtip; 397 struct malloc_type_stats *mtsp; 398 399 critical_enter(); 400 mtip = mtp->ks_handle; 401 mtsp = &mtip->mti_stats[curcpu]; 402 mtsp->mts_memfreed += size; 403 mtsp->mts_numfrees++; 404 405 #ifdef KDTRACE_HOOKS 406 if (dtrace_malloc_probe != NULL) { 407 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_FREE]; 408 if (probe_id != 0) 409 (dtrace_malloc_probe)(probe_id, 410 (uintptr_t) mtp, (uintptr_t) mtip, 411 (uintptr_t) mtsp, size, 0); 412 } 413 #endif 414 415 critical_exit(); 416 } 417 418 /* 419 * contigmalloc: 420 * 421 * Allocate a block of physically contiguous memory. 422 * 423 * If M_NOWAIT is set, this routine will not block and return NULL if 424 * the allocation fails. 425 */ 426 void * 427 contigmalloc(unsigned long size, struct malloc_type *type, int flags, 428 vm_paddr_t low, vm_paddr_t high, unsigned long alignment, 429 vm_paddr_t boundary) 430 { 431 void *ret; 432 433 ret = (void *)kmem_alloc_contig(kernel_map, size, flags, low, high, 434 alignment, boundary, VM_MEMATTR_DEFAULT); 435 if (ret != NULL) 436 malloc_type_allocated(type, round_page(size)); 437 return (ret); 438 } 439 440 /* 441 * contigfree: 442 * 443 * Free a block of memory allocated by contigmalloc. 444 * 445 * This routine may not block. 446 */ 447 void 448 contigfree(void *addr, unsigned long size, struct malloc_type *type) 449 { 450 451 kmem_free(kernel_map, (vm_offset_t)addr, size); 452 malloc_type_freed(type, round_page(size)); 453 } 454 455 /* 456 * malloc: 457 * 458 * Allocate a block of memory. 459 * 460 * If M_NOWAIT is set, this routine will not block and return NULL if 461 * the allocation fails. 462 */ 463 void * 464 malloc(unsigned long size, struct malloc_type *mtp, int flags) 465 { 466 int indx; 467 struct malloc_type_internal *mtip; 468 caddr_t va; 469 uma_zone_t zone; 470 #if defined(DIAGNOSTIC) || defined(DEBUG_REDZONE) 471 unsigned long osize = size; 472 #endif 473 474 #ifdef INVARIANTS 475 KASSERT(mtp->ks_magic == M_MAGIC, ("malloc: bad malloc type magic")); 476 /* 477 * Check that exactly one of M_WAITOK or M_NOWAIT is specified. 478 */ 479 indx = flags & (M_WAITOK | M_NOWAIT); 480 if (indx != M_NOWAIT && indx != M_WAITOK) { 481 static struct timeval lasterr; 482 static int curerr, once; 483 if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) { 484 printf("Bad malloc flags: %x\n", indx); 485 kdb_backtrace(); 486 flags |= M_WAITOK; 487 once++; 488 } 489 } 490 #endif 491 #ifdef MALLOC_MAKE_FAILURES 492 if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) { 493 atomic_add_int(&malloc_nowait_count, 1); 494 if ((malloc_nowait_count % malloc_failure_rate) == 0) { 495 atomic_add_int(&malloc_failure_count, 1); 496 t_malloc_fail = time_uptime; 497 return (NULL); 498 } 499 } 500 #endif 501 if (flags & M_WAITOK) 502 KASSERT(curthread->td_intr_nesting_level == 0, 503 ("malloc(M_WAITOK) in interrupt context")); 504 505 #ifdef DEBUG_MEMGUARD 506 if (memguard_cmp_mtp(mtp, size)) { 507 va = memguard_alloc(size, flags); 508 if (va != NULL) 509 return (va); 510 /* This is unfortunate but should not be fatal. */ 511 } 512 #endif 513 514 #ifdef DEBUG_REDZONE 515 size = redzone_size_ntor(size); 516 #endif 517 518 if (size <= KMEM_ZMAX) { 519 mtip = mtp->ks_handle; 520 if (size & KMEM_ZMASK) 521 size = (size & ~KMEM_ZMASK) + KMEM_ZBASE; 522 indx = kmemsize[size >> KMEM_ZSHIFT]; 523 KASSERT(mtip->mti_zone < numzones, 524 ("mti_zone %u out of range %d", 525 mtip->mti_zone, numzones)); 526 zone = kmemzones[indx].kz_zone[mtip->mti_zone]; 527 #ifdef MALLOC_PROFILE 528 krequests[size >> KMEM_ZSHIFT]++; 529 #endif 530 va = uma_zalloc(zone, flags); 531 if (va != NULL) 532 size = zone->uz_size; 533 malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx); 534 } else { 535 size = roundup(size, PAGE_SIZE); 536 zone = NULL; 537 va = uma_large_malloc(size, flags); 538 malloc_type_allocated(mtp, va == NULL ? 0 : size); 539 } 540 if (flags & M_WAITOK) 541 KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL")); 542 else if (va == NULL) 543 t_malloc_fail = time_uptime; 544 #ifdef DIAGNOSTIC 545 if (va != NULL && !(flags & M_ZERO)) { 546 memset(va, 0x70, osize); 547 } 548 #endif 549 #ifdef DEBUG_REDZONE 550 if (va != NULL) 551 va = redzone_setup(va, osize); 552 #endif 553 return ((void *) va); 554 } 555 556 /* 557 * free: 558 * 559 * Free a block of memory allocated by malloc. 560 * 561 * This routine may not block. 562 */ 563 void 564 free(void *addr, struct malloc_type *mtp) 565 { 566 uma_slab_t slab; 567 u_long size; 568 569 KASSERT(mtp->ks_magic == M_MAGIC, ("free: bad malloc type magic")); 570 571 /* free(NULL, ...) does nothing */ 572 if (addr == NULL) 573 return; 574 575 #ifdef DEBUG_MEMGUARD 576 if (is_memguard_addr(addr)) { 577 memguard_free(addr); 578 return; 579 } 580 #endif 581 582 #ifdef DEBUG_REDZONE 583 redzone_check(addr); 584 addr = redzone_addr_ntor(addr); 585 #endif 586 587 slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK)); 588 589 if (slab == NULL) 590 panic("free: address %p(%p) has not been allocated.\n", 591 addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); 592 593 594 if (!(slab->us_flags & UMA_SLAB_MALLOC)) { 595 #ifdef INVARIANTS 596 struct malloc_type **mtpp = addr; 597 #endif 598 size = slab->us_keg->uk_size; 599 #ifdef INVARIANTS 600 /* 601 * Cache a pointer to the malloc_type that most recently freed 602 * this memory here. This way we know who is most likely to 603 * have stepped on it later. 604 * 605 * This code assumes that size is a multiple of 8 bytes for 606 * 64 bit machines 607 */ 608 mtpp = (struct malloc_type **) 609 ((unsigned long)mtpp & ~UMA_ALIGN_PTR); 610 mtpp += (size - sizeof(struct malloc_type *)) / 611 sizeof(struct malloc_type *); 612 *mtpp = mtp; 613 #endif 614 uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab); 615 } else { 616 size = slab->us_size; 617 uma_large_free(slab); 618 } 619 malloc_type_freed(mtp, size); 620 } 621 622 /* 623 * realloc: change the size of a memory block 624 */ 625 void * 626 realloc(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 627 { 628 uma_slab_t slab; 629 unsigned long alloc; 630 void *newaddr; 631 632 KASSERT(mtp->ks_magic == M_MAGIC, 633 ("realloc: bad malloc type magic")); 634 635 /* realloc(NULL, ...) is equivalent to malloc(...) */ 636 if (addr == NULL) 637 return (malloc(size, mtp, flags)); 638 639 /* 640 * XXX: Should report free of old memory and alloc of new memory to 641 * per-CPU stats. 642 */ 643 644 #ifdef DEBUG_MEMGUARD 645 if (is_memguard_addr(addr)) 646 return (memguard_realloc(addr, size, mtp, flags)); 647 #endif 648 649 #ifdef DEBUG_REDZONE 650 slab = NULL; 651 alloc = redzone_get_size(addr); 652 #else 653 slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK)); 654 655 /* Sanity check */ 656 KASSERT(slab != NULL, 657 ("realloc: address %p out of range", (void *)addr)); 658 659 /* Get the size of the original block */ 660 if (!(slab->us_flags & UMA_SLAB_MALLOC)) 661 alloc = slab->us_keg->uk_size; 662 else 663 alloc = slab->us_size; 664 665 /* Reuse the original block if appropriate */ 666 if (size <= alloc 667 && (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE)) 668 return (addr); 669 #endif /* !DEBUG_REDZONE */ 670 671 /* Allocate a new, bigger (or smaller) block */ 672 if ((newaddr = malloc(size, mtp, flags)) == NULL) 673 return (NULL); 674 675 /* Copy over original contents */ 676 bcopy(addr, newaddr, min(size, alloc)); 677 free(addr, mtp); 678 return (newaddr); 679 } 680 681 /* 682 * reallocf: same as realloc() but free memory on failure. 683 */ 684 void * 685 reallocf(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 686 { 687 void *mem; 688 689 if ((mem = realloc(addr, size, mtp, flags)) == NULL) 690 free(addr, mtp); 691 return (mem); 692 } 693 694 /* 695 * Initialize the kernel memory allocator 696 */ 697 /* ARGSUSED*/ 698 static void 699 kmeminit(void *dummy) 700 { 701 uint8_t indx; 702 u_long mem_size, tmp; 703 int i; 704 705 mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF); 706 707 /* 708 * Try to auto-tune the kernel memory size, so that it is 709 * more applicable for a wider range of machine sizes. The 710 * VM_KMEM_SIZE_MAX is dependent on the maximum KVA space 711 * available. 712 * 713 * Note that the kmem_map is also used by the zone allocator, 714 * so make sure that there is enough space. 715 */ 716 vm_kmem_size = VM_KMEM_SIZE + nmbclusters * PAGE_SIZE; 717 mem_size = cnt.v_page_count; 718 719 #if defined(VM_KMEM_SIZE_SCALE) 720 vm_kmem_size_scale = VM_KMEM_SIZE_SCALE; 721 #endif 722 TUNABLE_INT_FETCH("vm.kmem_size_scale", &vm_kmem_size_scale); 723 if (vm_kmem_size_scale > 0 && 724 (mem_size / vm_kmem_size_scale) > (vm_kmem_size / PAGE_SIZE)) 725 vm_kmem_size = (mem_size / vm_kmem_size_scale) * PAGE_SIZE; 726 727 #if defined(VM_KMEM_SIZE_MIN) 728 vm_kmem_size_min = VM_KMEM_SIZE_MIN; 729 #endif 730 TUNABLE_ULONG_FETCH("vm.kmem_size_min", &vm_kmem_size_min); 731 if (vm_kmem_size_min > 0 && vm_kmem_size < vm_kmem_size_min) { 732 vm_kmem_size = vm_kmem_size_min; 733 } 734 735 #if defined(VM_KMEM_SIZE_MAX) 736 vm_kmem_size_max = VM_KMEM_SIZE_MAX; 737 #endif 738 TUNABLE_ULONG_FETCH("vm.kmem_size_max", &vm_kmem_size_max); 739 if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max) 740 vm_kmem_size = vm_kmem_size_max; 741 742 /* Allow final override from the kernel environment */ 743 TUNABLE_ULONG_FETCH("vm.kmem_size", &vm_kmem_size); 744 745 /* 746 * Limit kmem virtual size to twice the physical memory. 747 * This allows for kmem map sparseness, but limits the size 748 * to something sane. Be careful to not overflow the 32bit 749 * ints while doing the check or the adjustment. 750 */ 751 if (vm_kmem_size / 2 / PAGE_SIZE > mem_size) 752 vm_kmem_size = 2 * mem_size * PAGE_SIZE; 753 754 #ifdef DEBUG_MEMGUARD 755 tmp = memguard_fudge(vm_kmem_size, kernel_map); 756 #else 757 tmp = vm_kmem_size; 758 #endif 759 kmem_map = kmem_suballoc(kernel_map, &kmembase, &kmemlimit, 760 tmp, TRUE); 761 kmem_map->system_map = 1; 762 763 #ifdef DEBUG_MEMGUARD 764 /* 765 * Initialize MemGuard if support compiled in. MemGuard is a 766 * replacement allocator used for detecting tamper-after-free 767 * scenarios as they occur. It is only used for debugging. 768 */ 769 memguard_init(kmem_map); 770 #endif 771 772 uma_startup2(); 773 774 mt_zone = uma_zcreate("mt_zone", sizeof(struct malloc_type_internal), 775 #ifdef INVARIANTS 776 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 777 #else 778 NULL, NULL, NULL, NULL, 779 #endif 780 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 781 for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) { 782 int size = kmemzones[indx].kz_size; 783 char *name = kmemzones[indx].kz_name; 784 int subzone; 785 786 for (subzone = 0; subzone < numzones; subzone++) { 787 kmemzones[indx].kz_zone[subzone] = 788 uma_zcreate(name, size, 789 #ifdef INVARIANTS 790 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 791 #else 792 NULL, NULL, NULL, NULL, 793 #endif 794 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 795 } 796 for (;i <= size; i+= KMEM_ZBASE) 797 kmemsize[i >> KMEM_ZSHIFT] = indx; 798 799 } 800 } 801 802 void 803 malloc_init(void *data) 804 { 805 struct malloc_type_internal *mtip; 806 struct malloc_type *mtp; 807 808 KASSERT(cnt.v_page_count != 0, ("malloc_register before vm_init")); 809 810 mtp = data; 811 if (mtp->ks_magic != M_MAGIC) 812 panic("malloc_init: bad malloc type magic"); 813 814 mtip = uma_zalloc(mt_zone, M_WAITOK | M_ZERO); 815 mtp->ks_handle = mtip; 816 mtip->mti_zone = mtp_get_subzone(mtp->ks_shortdesc); 817 818 mtx_lock(&malloc_mtx); 819 mtp->ks_next = kmemstatistics; 820 kmemstatistics = mtp; 821 kmemcount++; 822 mtx_unlock(&malloc_mtx); 823 } 824 825 void 826 malloc_uninit(void *data) 827 { 828 struct malloc_type_internal *mtip; 829 struct malloc_type_stats *mtsp; 830 struct malloc_type *mtp, *temp; 831 uma_slab_t slab; 832 long temp_allocs, temp_bytes; 833 int i; 834 835 mtp = data; 836 KASSERT(mtp->ks_magic == M_MAGIC, 837 ("malloc_uninit: bad malloc type magic")); 838 KASSERT(mtp->ks_handle != NULL, ("malloc_deregister: cookie NULL")); 839 840 mtx_lock(&malloc_mtx); 841 mtip = mtp->ks_handle; 842 mtp->ks_handle = NULL; 843 if (mtp != kmemstatistics) { 844 for (temp = kmemstatistics; temp != NULL; 845 temp = temp->ks_next) { 846 if (temp->ks_next == mtp) { 847 temp->ks_next = mtp->ks_next; 848 break; 849 } 850 } 851 KASSERT(temp, 852 ("malloc_uninit: type '%s' not found", mtp->ks_shortdesc)); 853 } else 854 kmemstatistics = mtp->ks_next; 855 kmemcount--; 856 mtx_unlock(&malloc_mtx); 857 858 /* 859 * Look for memory leaks. 860 */ 861 temp_allocs = temp_bytes = 0; 862 for (i = 0; i < MAXCPU; i++) { 863 mtsp = &mtip->mti_stats[i]; 864 temp_allocs += mtsp->mts_numallocs; 865 temp_allocs -= mtsp->mts_numfrees; 866 temp_bytes += mtsp->mts_memalloced; 867 temp_bytes -= mtsp->mts_memfreed; 868 } 869 if (temp_allocs > 0 || temp_bytes > 0) { 870 printf("Warning: memory type %s leaked memory on destroy " 871 "(%ld allocations, %ld bytes leaked).\n", mtp->ks_shortdesc, 872 temp_allocs, temp_bytes); 873 } 874 875 slab = vtoslab((vm_offset_t) mtip & (~UMA_SLAB_MASK)); 876 uma_zfree_arg(mt_zone, mtip, slab); 877 } 878 879 struct malloc_type * 880 malloc_desc2type(const char *desc) 881 { 882 struct malloc_type *mtp; 883 884 mtx_assert(&malloc_mtx, MA_OWNED); 885 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 886 if (strcmp(mtp->ks_shortdesc, desc) == 0) 887 return (mtp); 888 } 889 return (NULL); 890 } 891 892 static int 893 sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS) 894 { 895 struct malloc_type_stream_header mtsh; 896 struct malloc_type_internal *mtip; 897 struct malloc_type_header mth; 898 struct malloc_type *mtp; 899 int error, i; 900 struct sbuf sbuf; 901 902 error = sysctl_wire_old_buffer(req, 0); 903 if (error != 0) 904 return (error); 905 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 906 mtx_lock(&malloc_mtx); 907 908 /* 909 * Insert stream header. 910 */ 911 bzero(&mtsh, sizeof(mtsh)); 912 mtsh.mtsh_version = MALLOC_TYPE_STREAM_VERSION; 913 mtsh.mtsh_maxcpus = MAXCPU; 914 mtsh.mtsh_count = kmemcount; 915 (void)sbuf_bcat(&sbuf, &mtsh, sizeof(mtsh)); 916 917 /* 918 * Insert alternating sequence of type headers and type statistics. 919 */ 920 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 921 mtip = (struct malloc_type_internal *)mtp->ks_handle; 922 923 /* 924 * Insert type header. 925 */ 926 bzero(&mth, sizeof(mth)); 927 strlcpy(mth.mth_name, mtp->ks_shortdesc, MALLOC_MAX_NAME); 928 (void)sbuf_bcat(&sbuf, &mth, sizeof(mth)); 929 930 /* 931 * Insert type statistics for each CPU. 932 */ 933 for (i = 0; i < MAXCPU; i++) { 934 (void)sbuf_bcat(&sbuf, &mtip->mti_stats[i], 935 sizeof(mtip->mti_stats[i])); 936 } 937 } 938 mtx_unlock(&malloc_mtx); 939 error = sbuf_finish(&sbuf); 940 sbuf_delete(&sbuf); 941 return (error); 942 } 943 944 SYSCTL_PROC(_kern, OID_AUTO, malloc_stats, CTLFLAG_RD|CTLTYPE_STRUCT, 945 0, 0, sysctl_kern_malloc_stats, "s,malloc_type_ustats", 946 "Return malloc types"); 947 948 SYSCTL_INT(_kern, OID_AUTO, malloc_count, CTLFLAG_RD, &kmemcount, 0, 949 "Count of kernel malloc types"); 950 951 void 952 malloc_type_list(malloc_type_list_func_t *func, void *arg) 953 { 954 struct malloc_type *mtp, **bufmtp; 955 int count, i; 956 size_t buflen; 957 958 mtx_lock(&malloc_mtx); 959 restart: 960 mtx_assert(&malloc_mtx, MA_OWNED); 961 count = kmemcount; 962 mtx_unlock(&malloc_mtx); 963 964 buflen = sizeof(struct malloc_type *) * count; 965 bufmtp = malloc(buflen, M_TEMP, M_WAITOK); 966 967 mtx_lock(&malloc_mtx); 968 969 if (count < kmemcount) { 970 free(bufmtp, M_TEMP); 971 goto restart; 972 } 973 974 for (mtp = kmemstatistics, i = 0; mtp != NULL; mtp = mtp->ks_next, i++) 975 bufmtp[i] = mtp; 976 977 mtx_unlock(&malloc_mtx); 978 979 for (i = 0; i < count; i++) 980 (func)(bufmtp[i], arg); 981 982 free(bufmtp, M_TEMP); 983 } 984 985 #ifdef DDB 986 DB_SHOW_COMMAND(malloc, db_show_malloc) 987 { 988 struct malloc_type_internal *mtip; 989 struct malloc_type *mtp; 990 uint64_t allocs, frees; 991 uint64_t alloced, freed; 992 int i; 993 994 db_printf("%18s %12s %12s %12s\n", "Type", "InUse", "MemUse", 995 "Requests"); 996 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 997 mtip = (struct malloc_type_internal *)mtp->ks_handle; 998 allocs = 0; 999 frees = 0; 1000 alloced = 0; 1001 freed = 0; 1002 for (i = 0; i < MAXCPU; i++) { 1003 allocs += mtip->mti_stats[i].mts_numallocs; 1004 frees += mtip->mti_stats[i].mts_numfrees; 1005 alloced += mtip->mti_stats[i].mts_memalloced; 1006 freed += mtip->mti_stats[i].mts_memfreed; 1007 } 1008 db_printf("%18s %12ju %12juK %12ju\n", 1009 mtp->ks_shortdesc, allocs - frees, 1010 (alloced - freed + 1023) / 1024, allocs); 1011 if (db_pager_quit) 1012 break; 1013 } 1014 } 1015 1016 #if MALLOC_DEBUG_MAXZONES > 1 1017 DB_SHOW_COMMAND(multizone_matches, db_show_multizone_matches) 1018 { 1019 struct malloc_type_internal *mtip; 1020 struct malloc_type *mtp; 1021 u_int subzone; 1022 1023 if (!have_addr) { 1024 db_printf("Usage: show multizone_matches <malloc type/addr>\n"); 1025 return; 1026 } 1027 mtp = (void *)addr; 1028 if (mtp->ks_magic != M_MAGIC) { 1029 db_printf("Magic %lx does not match expected %x\n", 1030 mtp->ks_magic, M_MAGIC); 1031 return; 1032 } 1033 1034 mtip = mtp->ks_handle; 1035 subzone = mtip->mti_zone; 1036 1037 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 1038 mtip = mtp->ks_handle; 1039 if (mtip->mti_zone != subzone) 1040 continue; 1041 db_printf("%s\n", mtp->ks_shortdesc); 1042 if (db_pager_quit) 1043 break; 1044 } 1045 } 1046 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 1047 #endif /* DDB */ 1048 1049 #ifdef MALLOC_PROFILE 1050 1051 static int 1052 sysctl_kern_mprof(SYSCTL_HANDLER_ARGS) 1053 { 1054 struct sbuf sbuf; 1055 uint64_t count; 1056 uint64_t waste; 1057 uint64_t mem; 1058 int error; 1059 int rsize; 1060 int size; 1061 int i; 1062 1063 waste = 0; 1064 mem = 0; 1065 1066 error = sysctl_wire_old_buffer(req, 0); 1067 if (error != 0) 1068 return (error); 1069 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 1070 sbuf_printf(&sbuf, 1071 "\n Size Requests Real Size\n"); 1072 for (i = 0; i < KMEM_ZSIZE; i++) { 1073 size = i << KMEM_ZSHIFT; 1074 rsize = kmemzones[kmemsize[i]].kz_size; 1075 count = (long long unsigned)krequests[i]; 1076 1077 sbuf_printf(&sbuf, "%6d%28llu%11d\n", size, 1078 (unsigned long long)count, rsize); 1079 1080 if ((rsize * count) > (size * count)) 1081 waste += (rsize * count) - (size * count); 1082 mem += (rsize * count); 1083 } 1084 sbuf_printf(&sbuf, 1085 "\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n", 1086 (unsigned long long)mem, (unsigned long long)waste); 1087 error = sbuf_finish(&sbuf); 1088 sbuf_delete(&sbuf); 1089 return (error); 1090 } 1091 1092 SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD, 1093 NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling"); 1094 #endif /* MALLOC_PROFILE */ 1095