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_vm.h" 50 51 #include <sys/param.h> 52 #include <sys/systm.h> 53 #include <sys/kdb.h> 54 #include <sys/kernel.h> 55 #include <sys/lock.h> 56 #include <sys/malloc.h> 57 #include <sys/mutex.h> 58 #include <sys/vmmeter.h> 59 #include <sys/proc.h> 60 #include <sys/sbuf.h> 61 #include <sys/sysctl.h> 62 #include <sys/time.h> 63 #include <sys/vmem.h> 64 65 #include <vm/vm.h> 66 #include <vm/pmap.h> 67 #include <vm/vm_pageout.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 struct malloc_type *kmemstatistics; 117 static int kmemcount; 118 119 #define KMEM_ZSHIFT 4 120 #define KMEM_ZBASE 16 121 #define KMEM_ZMASK (KMEM_ZBASE - 1) 122 123 #define KMEM_ZMAX PAGE_SIZE 124 #define KMEM_ZSIZE (KMEM_ZMAX >> KMEM_ZSHIFT) 125 static uint8_t kmemsize[KMEM_ZSIZE + 1]; 126 127 #ifndef MALLOC_DEBUG_MAXZONES 128 #define MALLOC_DEBUG_MAXZONES 1 129 #endif 130 static int numzones = MALLOC_DEBUG_MAXZONES; 131 132 /* 133 * Small malloc(9) memory allocations are allocated from a set of UMA buckets 134 * of various sizes. 135 * 136 * XXX: The comment here used to read "These won't be powers of two for 137 * long." It's possible that a significant amount of wasted memory could be 138 * recovered by tuning the sizes of these buckets. 139 */ 140 struct { 141 int kz_size; 142 char *kz_name; 143 uma_zone_t kz_zone[MALLOC_DEBUG_MAXZONES]; 144 } kmemzones[] = { 145 {16, "16", }, 146 {32, "32", }, 147 {64, "64", }, 148 {128, "128", }, 149 {256, "256", }, 150 {512, "512", }, 151 {1024, "1024", }, 152 {2048, "2048", }, 153 {4096, "4096", }, 154 #if PAGE_SIZE > 4096 155 {8192, "8192", }, 156 #if PAGE_SIZE > 8192 157 {16384, "16384", }, 158 #if PAGE_SIZE > 16384 159 {32768, "32768", }, 160 #if PAGE_SIZE > 32768 161 {65536, "65536", }, 162 #if PAGE_SIZE > 65536 163 #error "Unsupported PAGE_SIZE" 164 #endif /* 65536 */ 165 #endif /* 32768 */ 166 #endif /* 16384 */ 167 #endif /* 8192 */ 168 #endif /* 4096 */ 169 {0, NULL}, 170 }; 171 172 /* 173 * Zone to allocate malloc type descriptions from. For ABI reasons, memory 174 * types are described by a data structure passed by the declaring code, but 175 * the malloc(9) implementation has its own data structure describing the 176 * type and statistics. This permits the malloc(9)-internal data structures 177 * to be modified without breaking binary-compiled kernel modules that 178 * declare malloc types. 179 */ 180 static uma_zone_t mt_zone; 181 182 u_long vm_kmem_size; 183 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size, CTLFLAG_RDTUN, &vm_kmem_size, 0, 184 "Size of kernel memory"); 185 186 static u_long vm_kmem_size_min; 187 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_min, CTLFLAG_RDTUN, &vm_kmem_size_min, 0, 188 "Minimum size of kernel memory"); 189 190 static u_long vm_kmem_size_max; 191 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RDTUN, &vm_kmem_size_max, 0, 192 "Maximum size of kernel memory"); 193 194 static u_int vm_kmem_size_scale; 195 SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RDTUN, &vm_kmem_size_scale, 0, 196 "Scale factor for kernel memory size"); 197 198 static int sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS); 199 SYSCTL_PROC(_vm, OID_AUTO, kmem_map_size, 200 CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, 201 sysctl_kmem_map_size, "LU", "Current kmem allocation size"); 202 203 static int sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS); 204 SYSCTL_PROC(_vm, OID_AUTO, kmem_map_free, 205 CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, 206 sysctl_kmem_map_free, "LU", "Free space in kmem"); 207 208 /* 209 * The malloc_mtx protects the kmemstatistics linked list. 210 */ 211 struct mtx malloc_mtx; 212 213 #ifdef MALLOC_PROFILE 214 uint64_t krequests[KMEM_ZSIZE + 1]; 215 216 static int sysctl_kern_mprof(SYSCTL_HANDLER_ARGS); 217 #endif 218 219 static int sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS); 220 221 /* 222 * time_uptime of the last malloc(9) failure (induced or real). 223 */ 224 static time_t t_malloc_fail; 225 226 #if defined(MALLOC_MAKE_FAILURES) || (MALLOC_DEBUG_MAXZONES > 1) 227 static SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD, 0, 228 "Kernel malloc debugging options"); 229 #endif 230 231 /* 232 * malloc(9) fault injection -- cause malloc failures every (n) mallocs when 233 * the caller specifies M_NOWAIT. If set to 0, no failures are caused. 234 */ 235 #ifdef MALLOC_MAKE_FAILURES 236 static int malloc_failure_rate; 237 static int malloc_nowait_count; 238 static int malloc_failure_count; 239 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RW, 240 &malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail"); 241 TUNABLE_INT("debug.malloc.failure_rate", &malloc_failure_rate); 242 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD, 243 &malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures"); 244 #endif 245 246 static int 247 sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS) 248 { 249 u_long size; 250 251 size = vmem_size(kmem_arena, VMEM_ALLOC); 252 return (sysctl_handle_long(oidp, &size, 0, req)); 253 } 254 255 static int 256 sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS) 257 { 258 u_long size; 259 260 size = vmem_size(kmem_arena, VMEM_FREE); 261 return (sysctl_handle_long(oidp, &size, 0, req)); 262 } 263 264 /* 265 * malloc(9) uma zone separation -- sub-page buffer overruns in one 266 * malloc type will affect only a subset of other malloc types. 267 */ 268 #if MALLOC_DEBUG_MAXZONES > 1 269 static void 270 tunable_set_numzones(void) 271 { 272 273 TUNABLE_INT_FETCH("debug.malloc.numzones", 274 &numzones); 275 276 /* Sanity check the number of malloc uma zones. */ 277 if (numzones <= 0) 278 numzones = 1; 279 if (numzones > MALLOC_DEBUG_MAXZONES) 280 numzones = MALLOC_DEBUG_MAXZONES; 281 } 282 SYSINIT(numzones, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_set_numzones, NULL); 283 SYSCTL_INT(_debug_malloc, OID_AUTO, numzones, CTLFLAG_RDTUN, 284 &numzones, 0, "Number of malloc uma subzones"); 285 286 /* 287 * Any number that changes regularly is an okay choice for the 288 * offset. Build numbers are pretty good of you have them. 289 */ 290 static u_int zone_offset = __FreeBSD_version; 291 TUNABLE_INT("debug.malloc.zone_offset", &zone_offset); 292 SYSCTL_UINT(_debug_malloc, OID_AUTO, zone_offset, CTLFLAG_RDTUN, 293 &zone_offset, 0, "Separate malloc types by examining the " 294 "Nth character in the malloc type short description."); 295 296 static u_int 297 mtp_get_subzone(const char *desc) 298 { 299 size_t len; 300 u_int val; 301 302 if (desc == NULL || (len = strlen(desc)) == 0) 303 return (0); 304 val = desc[zone_offset % len]; 305 return (val % numzones); 306 } 307 #elif MALLOC_DEBUG_MAXZONES == 0 308 #error "MALLOC_DEBUG_MAXZONES must be positive." 309 #else 310 static inline u_int 311 mtp_get_subzone(const char *desc) 312 { 313 314 return (0); 315 } 316 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 317 318 int 319 malloc_last_fail(void) 320 { 321 322 return (time_uptime - t_malloc_fail); 323 } 324 325 /* 326 * An allocation has succeeded -- update malloc type statistics for the 327 * amount of bucket size. Occurs within a critical section so that the 328 * thread isn't preempted and doesn't migrate while updating per-PCU 329 * statistics. 330 */ 331 static void 332 malloc_type_zone_allocated(struct malloc_type *mtp, unsigned long size, 333 int zindx) 334 { 335 struct malloc_type_internal *mtip; 336 struct malloc_type_stats *mtsp; 337 338 critical_enter(); 339 mtip = mtp->ks_handle; 340 mtsp = &mtip->mti_stats[curcpu]; 341 if (size > 0) { 342 mtsp->mts_memalloced += size; 343 mtsp->mts_numallocs++; 344 } 345 if (zindx != -1) 346 mtsp->mts_size |= 1 << zindx; 347 348 #ifdef KDTRACE_HOOKS 349 if (dtrace_malloc_probe != NULL) { 350 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_MALLOC]; 351 if (probe_id != 0) 352 (dtrace_malloc_probe)(probe_id, 353 (uintptr_t) mtp, (uintptr_t) mtip, 354 (uintptr_t) mtsp, size, zindx); 355 } 356 #endif 357 358 critical_exit(); 359 } 360 361 void 362 malloc_type_allocated(struct malloc_type *mtp, unsigned long size) 363 { 364 365 if (size > 0) 366 malloc_type_zone_allocated(mtp, size, -1); 367 } 368 369 /* 370 * A free operation has occurred -- update malloc type statistics for the 371 * amount of the bucket size. Occurs within a critical section so that the 372 * thread isn't preempted and doesn't migrate while updating per-CPU 373 * statistics. 374 */ 375 void 376 malloc_type_freed(struct malloc_type *mtp, unsigned long size) 377 { 378 struct malloc_type_internal *mtip; 379 struct malloc_type_stats *mtsp; 380 381 critical_enter(); 382 mtip = mtp->ks_handle; 383 mtsp = &mtip->mti_stats[curcpu]; 384 mtsp->mts_memfreed += size; 385 mtsp->mts_numfrees++; 386 387 #ifdef KDTRACE_HOOKS 388 if (dtrace_malloc_probe != NULL) { 389 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_FREE]; 390 if (probe_id != 0) 391 (dtrace_malloc_probe)(probe_id, 392 (uintptr_t) mtp, (uintptr_t) mtip, 393 (uintptr_t) mtsp, size, 0); 394 } 395 #endif 396 397 critical_exit(); 398 } 399 400 /* 401 * contigmalloc: 402 * 403 * Allocate a block of physically contiguous memory. 404 * 405 * If M_NOWAIT is set, this routine will not block and return NULL if 406 * the allocation fails. 407 */ 408 void * 409 contigmalloc(unsigned long size, struct malloc_type *type, int flags, 410 vm_paddr_t low, vm_paddr_t high, unsigned long alignment, 411 vm_paddr_t boundary) 412 { 413 void *ret; 414 415 ret = (void *)kmem_alloc_contig(kernel_arena, size, flags, low, high, 416 alignment, boundary, VM_MEMATTR_DEFAULT); 417 if (ret != NULL) 418 malloc_type_allocated(type, round_page(size)); 419 return (ret); 420 } 421 422 /* 423 * contigfree: 424 * 425 * Free a block of memory allocated by contigmalloc. 426 * 427 * This routine may not block. 428 */ 429 void 430 contigfree(void *addr, unsigned long size, struct malloc_type *type) 431 { 432 433 kmem_free(kernel_arena, (vm_offset_t)addr, size); 434 malloc_type_freed(type, round_page(size)); 435 } 436 437 /* 438 * malloc: 439 * 440 * Allocate a block of memory. 441 * 442 * If M_NOWAIT is set, this routine will not block and return NULL if 443 * the allocation fails. 444 */ 445 void * 446 malloc(unsigned long size, struct malloc_type *mtp, int flags) 447 { 448 int indx; 449 struct malloc_type_internal *mtip; 450 caddr_t va; 451 uma_zone_t zone; 452 #if defined(DIAGNOSTIC) || defined(DEBUG_REDZONE) 453 unsigned long osize = size; 454 #endif 455 456 #ifdef INVARIANTS 457 KASSERT(mtp->ks_magic == M_MAGIC, ("malloc: bad malloc type magic")); 458 /* 459 * Check that exactly one of M_WAITOK or M_NOWAIT is specified. 460 */ 461 indx = flags & (M_WAITOK | M_NOWAIT); 462 if (indx != M_NOWAIT && indx != M_WAITOK) { 463 static struct timeval lasterr; 464 static int curerr, once; 465 if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) { 466 printf("Bad malloc flags: %x\n", indx); 467 kdb_backtrace(); 468 flags |= M_WAITOK; 469 once++; 470 } 471 } 472 #endif 473 #ifdef MALLOC_MAKE_FAILURES 474 if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) { 475 atomic_add_int(&malloc_nowait_count, 1); 476 if ((malloc_nowait_count % malloc_failure_rate) == 0) { 477 atomic_add_int(&malloc_failure_count, 1); 478 t_malloc_fail = time_uptime; 479 return (NULL); 480 } 481 } 482 #endif 483 if (flags & M_WAITOK) 484 KASSERT(curthread->td_intr_nesting_level == 0, 485 ("malloc(M_WAITOK) in interrupt context")); 486 487 #ifdef DEBUG_MEMGUARD 488 if (memguard_cmp_mtp(mtp, size)) { 489 va = memguard_alloc(size, flags); 490 if (va != NULL) 491 return (va); 492 /* This is unfortunate but should not be fatal. */ 493 } 494 #endif 495 496 #ifdef DEBUG_REDZONE 497 size = redzone_size_ntor(size); 498 #endif 499 500 if (size <= KMEM_ZMAX) { 501 mtip = mtp->ks_handle; 502 if (size & KMEM_ZMASK) 503 size = (size & ~KMEM_ZMASK) + KMEM_ZBASE; 504 indx = kmemsize[size >> KMEM_ZSHIFT]; 505 KASSERT(mtip->mti_zone < numzones, 506 ("mti_zone %u out of range %d", 507 mtip->mti_zone, numzones)); 508 zone = kmemzones[indx].kz_zone[mtip->mti_zone]; 509 #ifdef MALLOC_PROFILE 510 krequests[size >> KMEM_ZSHIFT]++; 511 #endif 512 va = uma_zalloc(zone, flags); 513 if (va != NULL) 514 size = zone->uz_size; 515 malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx); 516 } else { 517 size = roundup(size, PAGE_SIZE); 518 zone = NULL; 519 va = uma_large_malloc(size, flags); 520 malloc_type_allocated(mtp, va == NULL ? 0 : size); 521 } 522 if (flags & M_WAITOK) 523 KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL")); 524 else if (va == NULL) 525 t_malloc_fail = time_uptime; 526 #ifdef DIAGNOSTIC 527 if (va != NULL && !(flags & M_ZERO)) { 528 memset(va, 0x70, osize); 529 } 530 #endif 531 #ifdef DEBUG_REDZONE 532 if (va != NULL) 533 va = redzone_setup(va, osize); 534 #endif 535 return ((void *) va); 536 } 537 538 /* 539 * free: 540 * 541 * Free a block of memory allocated by malloc. 542 * 543 * This routine may not block. 544 */ 545 void 546 free(void *addr, struct malloc_type *mtp) 547 { 548 uma_slab_t slab; 549 u_long size; 550 551 KASSERT(mtp->ks_magic == M_MAGIC, ("free: bad malloc type magic")); 552 553 /* free(NULL, ...) does nothing */ 554 if (addr == NULL) 555 return; 556 557 #ifdef DEBUG_MEMGUARD 558 if (is_memguard_addr(addr)) { 559 memguard_free(addr); 560 return; 561 } 562 #endif 563 564 #ifdef DEBUG_REDZONE 565 redzone_check(addr); 566 addr = redzone_addr_ntor(addr); 567 #endif 568 569 slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK)); 570 571 if (slab == NULL) 572 panic("free: address %p(%p) has not been allocated.\n", 573 addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); 574 575 if (!(slab->us_flags & UMA_SLAB_MALLOC)) { 576 #ifdef INVARIANTS 577 struct malloc_type **mtpp = addr; 578 #endif 579 size = slab->us_keg->uk_size; 580 #ifdef INVARIANTS 581 /* 582 * Cache a pointer to the malloc_type that most recently freed 583 * this memory here. This way we know who is most likely to 584 * have stepped on it later. 585 * 586 * This code assumes that size is a multiple of 8 bytes for 587 * 64 bit machines 588 */ 589 mtpp = (struct malloc_type **) 590 ((unsigned long)mtpp & ~UMA_ALIGN_PTR); 591 mtpp += (size - sizeof(struct malloc_type *)) / 592 sizeof(struct malloc_type *); 593 *mtpp = mtp; 594 #endif 595 uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab); 596 } else { 597 size = slab->us_size; 598 uma_large_free(slab); 599 } 600 malloc_type_freed(mtp, size); 601 } 602 603 /* 604 * realloc: change the size of a memory block 605 */ 606 void * 607 realloc(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 608 { 609 uma_slab_t slab; 610 unsigned long alloc; 611 void *newaddr; 612 613 KASSERT(mtp->ks_magic == M_MAGIC, 614 ("realloc: bad malloc type magic")); 615 616 /* realloc(NULL, ...) is equivalent to malloc(...) */ 617 if (addr == NULL) 618 return (malloc(size, mtp, flags)); 619 620 /* 621 * XXX: Should report free of old memory and alloc of new memory to 622 * per-CPU stats. 623 */ 624 625 #ifdef DEBUG_MEMGUARD 626 if (is_memguard_addr(addr)) 627 return (memguard_realloc(addr, size, mtp, flags)); 628 #endif 629 630 #ifdef DEBUG_REDZONE 631 slab = NULL; 632 alloc = redzone_get_size(addr); 633 #else 634 slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK)); 635 636 /* Sanity check */ 637 KASSERT(slab != NULL, 638 ("realloc: address %p out of range", (void *)addr)); 639 640 /* Get the size of the original block */ 641 if (!(slab->us_flags & UMA_SLAB_MALLOC)) 642 alloc = slab->us_keg->uk_size; 643 else 644 alloc = slab->us_size; 645 646 /* Reuse the original block if appropriate */ 647 if (size <= alloc 648 && (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE)) 649 return (addr); 650 #endif /* !DEBUG_REDZONE */ 651 652 /* Allocate a new, bigger (or smaller) block */ 653 if ((newaddr = malloc(size, mtp, flags)) == NULL) 654 return (NULL); 655 656 /* Copy over original contents */ 657 bcopy(addr, newaddr, min(size, alloc)); 658 free(addr, mtp); 659 return (newaddr); 660 } 661 662 /* 663 * reallocf: same as realloc() but free memory on failure. 664 */ 665 void * 666 reallocf(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 667 { 668 void *mem; 669 670 if ((mem = realloc(addr, size, mtp, flags)) == NULL) 671 free(addr, mtp); 672 return (mem); 673 } 674 675 /* 676 * Wake the page daemon when we exhaust KVA. It will call the lowmem handler 677 * and uma_reclaim() callbacks in a context that is safe. 678 */ 679 static void 680 kmem_reclaim(vmem_t *vm, int flags) 681 { 682 683 pagedaemon_wakeup(); 684 } 685 686 CTASSERT(VM_KMEM_SIZE_SCALE >= 1); 687 688 /* 689 * Initialize the kernel memory (kmem) arena. 690 */ 691 void 692 kmeminit(void) 693 { 694 u_long mem_size, tmp; 695 696 /* 697 * Calculate the amount of kernel virtual address (KVA) space that is 698 * preallocated to the kmem arena. In order to support a wide range 699 * of machines, it is a function of the physical memory size, 700 * specifically, 701 * 702 * min(max(physical memory size / VM_KMEM_SIZE_SCALE, 703 * VM_KMEM_SIZE_MIN), VM_KMEM_SIZE_MAX) 704 * 705 * Every architecture must define an integral value for 706 * VM_KMEM_SIZE_SCALE. However, the definitions of VM_KMEM_SIZE_MIN 707 * and VM_KMEM_SIZE_MAX, which represent respectively the floor and 708 * ceiling on this preallocation, are optional. Typically, 709 * VM_KMEM_SIZE_MAX is itself a function of the available KVA space on 710 * a given architecture. 711 */ 712 mem_size = cnt.v_page_count; 713 714 vm_kmem_size_scale = VM_KMEM_SIZE_SCALE; 715 TUNABLE_INT_FETCH("vm.kmem_size_scale", &vm_kmem_size_scale); 716 if (vm_kmem_size_scale < 1) 717 vm_kmem_size_scale = VM_KMEM_SIZE_SCALE; 718 719 vm_kmem_size = (mem_size / vm_kmem_size_scale) * PAGE_SIZE; 720 721 #if defined(VM_KMEM_SIZE_MIN) 722 vm_kmem_size_min = VM_KMEM_SIZE_MIN; 723 #endif 724 TUNABLE_ULONG_FETCH("vm.kmem_size_min", &vm_kmem_size_min); 725 if (vm_kmem_size_min > 0 && vm_kmem_size < vm_kmem_size_min) 726 vm_kmem_size = vm_kmem_size_min; 727 728 #if defined(VM_KMEM_SIZE_MAX) 729 vm_kmem_size_max = VM_KMEM_SIZE_MAX; 730 #endif 731 TUNABLE_ULONG_FETCH("vm.kmem_size_max", &vm_kmem_size_max); 732 if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max) 733 vm_kmem_size = vm_kmem_size_max; 734 735 /* 736 * Alternatively, the amount of KVA space that is preallocated to the 737 * kmem arena can be set statically at compile-time or manually 738 * through the kernel environment. However, it is still limited to 739 * twice the physical memory size, which has been sufficient to handle 740 * the most severe cases of external fragmentation in the kmem arena. 741 */ 742 #if defined(VM_KMEM_SIZE) 743 vm_kmem_size = VM_KMEM_SIZE; 744 #endif 745 TUNABLE_ULONG_FETCH("vm.kmem_size", &vm_kmem_size); 746 if (vm_kmem_size / 2 / PAGE_SIZE > mem_size) 747 vm_kmem_size = 2 * mem_size * PAGE_SIZE; 748 749 vm_kmem_size = round_page(vm_kmem_size); 750 #ifdef DEBUG_MEMGUARD 751 tmp = memguard_fudge(vm_kmem_size, kernel_map); 752 #else 753 tmp = vm_kmem_size; 754 #endif 755 vmem_init(kmem_arena, "kmem arena", kva_alloc(tmp), tmp, PAGE_SIZE, 756 0, 0); 757 vmem_set_reclaim(kmem_arena, kmem_reclaim); 758 759 #ifdef DEBUG_MEMGUARD 760 /* 761 * Initialize MemGuard if support compiled in. MemGuard is a 762 * replacement allocator used for detecting tamper-after-free 763 * scenarios as they occur. It is only used for debugging. 764 */ 765 memguard_init(kmem_arena); 766 #endif 767 } 768 769 /* 770 * Initialize the kernel memory allocator 771 */ 772 /* ARGSUSED*/ 773 static void 774 mallocinit(void *dummy) 775 { 776 int i; 777 uint8_t indx; 778 779 mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF); 780 781 kmeminit(); 782 783 uma_startup2(); 784 785 mt_zone = uma_zcreate("mt_zone", sizeof(struct malloc_type_internal), 786 #ifdef INVARIANTS 787 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 788 #else 789 NULL, NULL, NULL, NULL, 790 #endif 791 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 792 for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) { 793 int size = kmemzones[indx].kz_size; 794 char *name = kmemzones[indx].kz_name; 795 int subzone; 796 797 for (subzone = 0; subzone < numzones; subzone++) { 798 kmemzones[indx].kz_zone[subzone] = 799 uma_zcreate(name, size, 800 #ifdef INVARIANTS 801 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 802 #else 803 NULL, NULL, NULL, NULL, 804 #endif 805 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 806 } 807 for (;i <= size; i+= KMEM_ZBASE) 808 kmemsize[i >> KMEM_ZSHIFT] = indx; 809 810 } 811 } 812 SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, mallocinit, NULL); 813 814 void 815 malloc_init(void *data) 816 { 817 struct malloc_type_internal *mtip; 818 struct malloc_type *mtp; 819 820 KASSERT(cnt.v_page_count != 0, ("malloc_register before vm_init")); 821 822 mtp = data; 823 if (mtp->ks_magic != M_MAGIC) 824 panic("malloc_init: bad malloc type magic"); 825 826 mtip = uma_zalloc(mt_zone, M_WAITOK | M_ZERO); 827 mtp->ks_handle = mtip; 828 mtip->mti_zone = mtp_get_subzone(mtp->ks_shortdesc); 829 830 mtx_lock(&malloc_mtx); 831 mtp->ks_next = kmemstatistics; 832 kmemstatistics = mtp; 833 kmemcount++; 834 mtx_unlock(&malloc_mtx); 835 } 836 837 void 838 malloc_uninit(void *data) 839 { 840 struct malloc_type_internal *mtip; 841 struct malloc_type_stats *mtsp; 842 struct malloc_type *mtp, *temp; 843 uma_slab_t slab; 844 long temp_allocs, temp_bytes; 845 int i; 846 847 mtp = data; 848 KASSERT(mtp->ks_magic == M_MAGIC, 849 ("malloc_uninit: bad malloc type magic")); 850 KASSERT(mtp->ks_handle != NULL, ("malloc_deregister: cookie NULL")); 851 852 mtx_lock(&malloc_mtx); 853 mtip = mtp->ks_handle; 854 mtp->ks_handle = NULL; 855 if (mtp != kmemstatistics) { 856 for (temp = kmemstatistics; temp != NULL; 857 temp = temp->ks_next) { 858 if (temp->ks_next == mtp) { 859 temp->ks_next = mtp->ks_next; 860 break; 861 } 862 } 863 KASSERT(temp, 864 ("malloc_uninit: type '%s' not found", mtp->ks_shortdesc)); 865 } else 866 kmemstatistics = mtp->ks_next; 867 kmemcount--; 868 mtx_unlock(&malloc_mtx); 869 870 /* 871 * Look for memory leaks. 872 */ 873 temp_allocs = temp_bytes = 0; 874 for (i = 0; i < MAXCPU; i++) { 875 mtsp = &mtip->mti_stats[i]; 876 temp_allocs += mtsp->mts_numallocs; 877 temp_allocs -= mtsp->mts_numfrees; 878 temp_bytes += mtsp->mts_memalloced; 879 temp_bytes -= mtsp->mts_memfreed; 880 } 881 if (temp_allocs > 0 || temp_bytes > 0) { 882 printf("Warning: memory type %s leaked memory on destroy " 883 "(%ld allocations, %ld bytes leaked).\n", mtp->ks_shortdesc, 884 temp_allocs, temp_bytes); 885 } 886 887 slab = vtoslab((vm_offset_t) mtip & (~UMA_SLAB_MASK)); 888 uma_zfree_arg(mt_zone, mtip, slab); 889 } 890 891 struct malloc_type * 892 malloc_desc2type(const char *desc) 893 { 894 struct malloc_type *mtp; 895 896 mtx_assert(&malloc_mtx, MA_OWNED); 897 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 898 if (strcmp(mtp->ks_shortdesc, desc) == 0) 899 return (mtp); 900 } 901 return (NULL); 902 } 903 904 static int 905 sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS) 906 { 907 struct malloc_type_stream_header mtsh; 908 struct malloc_type_internal *mtip; 909 struct malloc_type_header mth; 910 struct malloc_type *mtp; 911 int error, i; 912 struct sbuf sbuf; 913 914 error = sysctl_wire_old_buffer(req, 0); 915 if (error != 0) 916 return (error); 917 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 918 mtx_lock(&malloc_mtx); 919 920 /* 921 * Insert stream header. 922 */ 923 bzero(&mtsh, sizeof(mtsh)); 924 mtsh.mtsh_version = MALLOC_TYPE_STREAM_VERSION; 925 mtsh.mtsh_maxcpus = MAXCPU; 926 mtsh.mtsh_count = kmemcount; 927 (void)sbuf_bcat(&sbuf, &mtsh, sizeof(mtsh)); 928 929 /* 930 * Insert alternating sequence of type headers and type statistics. 931 */ 932 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 933 mtip = (struct malloc_type_internal *)mtp->ks_handle; 934 935 /* 936 * Insert type header. 937 */ 938 bzero(&mth, sizeof(mth)); 939 strlcpy(mth.mth_name, mtp->ks_shortdesc, MALLOC_MAX_NAME); 940 (void)sbuf_bcat(&sbuf, &mth, sizeof(mth)); 941 942 /* 943 * Insert type statistics for each CPU. 944 */ 945 for (i = 0; i < MAXCPU; i++) { 946 (void)sbuf_bcat(&sbuf, &mtip->mti_stats[i], 947 sizeof(mtip->mti_stats[i])); 948 } 949 } 950 mtx_unlock(&malloc_mtx); 951 error = sbuf_finish(&sbuf); 952 sbuf_delete(&sbuf); 953 return (error); 954 } 955 956 SYSCTL_PROC(_kern, OID_AUTO, malloc_stats, CTLFLAG_RD|CTLTYPE_STRUCT, 957 0, 0, sysctl_kern_malloc_stats, "s,malloc_type_ustats", 958 "Return malloc types"); 959 960 SYSCTL_INT(_kern, OID_AUTO, malloc_count, CTLFLAG_RD, &kmemcount, 0, 961 "Count of kernel malloc types"); 962 963 void 964 malloc_type_list(malloc_type_list_func_t *func, void *arg) 965 { 966 struct malloc_type *mtp, **bufmtp; 967 int count, i; 968 size_t buflen; 969 970 mtx_lock(&malloc_mtx); 971 restart: 972 mtx_assert(&malloc_mtx, MA_OWNED); 973 count = kmemcount; 974 mtx_unlock(&malloc_mtx); 975 976 buflen = sizeof(struct malloc_type *) * count; 977 bufmtp = malloc(buflen, M_TEMP, M_WAITOK); 978 979 mtx_lock(&malloc_mtx); 980 981 if (count < kmemcount) { 982 free(bufmtp, M_TEMP); 983 goto restart; 984 } 985 986 for (mtp = kmemstatistics, i = 0; mtp != NULL; mtp = mtp->ks_next, i++) 987 bufmtp[i] = mtp; 988 989 mtx_unlock(&malloc_mtx); 990 991 for (i = 0; i < count; i++) 992 (func)(bufmtp[i], arg); 993 994 free(bufmtp, M_TEMP); 995 } 996 997 #ifdef DDB 998 DB_SHOW_COMMAND(malloc, db_show_malloc) 999 { 1000 struct malloc_type_internal *mtip; 1001 struct malloc_type *mtp; 1002 uint64_t allocs, frees; 1003 uint64_t alloced, freed; 1004 int i; 1005 1006 db_printf("%18s %12s %12s %12s\n", "Type", "InUse", "MemUse", 1007 "Requests"); 1008 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 1009 mtip = (struct malloc_type_internal *)mtp->ks_handle; 1010 allocs = 0; 1011 frees = 0; 1012 alloced = 0; 1013 freed = 0; 1014 for (i = 0; i < MAXCPU; i++) { 1015 allocs += mtip->mti_stats[i].mts_numallocs; 1016 frees += mtip->mti_stats[i].mts_numfrees; 1017 alloced += mtip->mti_stats[i].mts_memalloced; 1018 freed += mtip->mti_stats[i].mts_memfreed; 1019 } 1020 db_printf("%18s %12ju %12juK %12ju\n", 1021 mtp->ks_shortdesc, allocs - frees, 1022 (alloced - freed + 1023) / 1024, allocs); 1023 if (db_pager_quit) 1024 break; 1025 } 1026 } 1027 1028 #if MALLOC_DEBUG_MAXZONES > 1 1029 DB_SHOW_COMMAND(multizone_matches, db_show_multizone_matches) 1030 { 1031 struct malloc_type_internal *mtip; 1032 struct malloc_type *mtp; 1033 u_int subzone; 1034 1035 if (!have_addr) { 1036 db_printf("Usage: show multizone_matches <malloc type/addr>\n"); 1037 return; 1038 } 1039 mtp = (void *)addr; 1040 if (mtp->ks_magic != M_MAGIC) { 1041 db_printf("Magic %lx does not match expected %x\n", 1042 mtp->ks_magic, M_MAGIC); 1043 return; 1044 } 1045 1046 mtip = mtp->ks_handle; 1047 subzone = mtip->mti_zone; 1048 1049 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 1050 mtip = mtp->ks_handle; 1051 if (mtip->mti_zone != subzone) 1052 continue; 1053 db_printf("%s\n", mtp->ks_shortdesc); 1054 if (db_pager_quit) 1055 break; 1056 } 1057 } 1058 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 1059 #endif /* DDB */ 1060 1061 #ifdef MALLOC_PROFILE 1062 1063 static int 1064 sysctl_kern_mprof(SYSCTL_HANDLER_ARGS) 1065 { 1066 struct sbuf sbuf; 1067 uint64_t count; 1068 uint64_t waste; 1069 uint64_t mem; 1070 int error; 1071 int rsize; 1072 int size; 1073 int i; 1074 1075 waste = 0; 1076 mem = 0; 1077 1078 error = sysctl_wire_old_buffer(req, 0); 1079 if (error != 0) 1080 return (error); 1081 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 1082 sbuf_printf(&sbuf, 1083 "\n Size Requests Real Size\n"); 1084 for (i = 0; i < KMEM_ZSIZE; i++) { 1085 size = i << KMEM_ZSHIFT; 1086 rsize = kmemzones[kmemsize[i]].kz_size; 1087 count = (long long unsigned)krequests[i]; 1088 1089 sbuf_printf(&sbuf, "%6d%28llu%11d\n", size, 1090 (unsigned long long)count, rsize); 1091 1092 if ((rsize * count) > (size * count)) 1093 waste += (rsize * count) - (size * count); 1094 mem += (rsize * count); 1095 } 1096 sbuf_printf(&sbuf, 1097 "\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n", 1098 (unsigned long long)mem, (unsigned long long)waste); 1099 error = sbuf_finish(&sbuf); 1100 sbuf_delete(&sbuf); 1101 return (error); 1102 } 1103 1104 SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD, 1105 NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling"); 1106 #endif /* MALLOC_PROFILE */ 1107