1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1987, 1991, 1993 5 * The Regents of the University of California. 6 * Copyright (c) 2005-2009 Robert N. M. Watson 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. 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 */ 35 36 /* 37 * Kernel malloc(9) implementation -- general purpose kernel memory allocator 38 * based on memory types. Back end is implemented using the UMA(9) zone 39 * allocator. A set of fixed-size buckets are used for smaller allocations, 40 * and a special UMA allocation interface is used for larger allocations. 41 * Callers declare memory types, and statistics are maintained independently 42 * for each memory type. Statistics are maintained per-CPU for performance 43 * reasons. See malloc(9) and comments in malloc.h for a detailed 44 * description. 45 */ 46 47 #include <sys/cdefs.h> 48 __FBSDID("$FreeBSD$"); 49 50 #include "opt_ddb.h" 51 #include "opt_vm.h" 52 53 #include <sys/param.h> 54 #include <sys/systm.h> 55 #include <sys/kdb.h> 56 #include <sys/kernel.h> 57 #include <sys/lock.h> 58 #include <sys/malloc.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 #include <sys/vmem.h> 66 67 #include <vm/vm.h> 68 #include <vm/pmap.h> 69 #include <vm/vm_pageout.h> 70 #include <vm/vm_param.h> 71 #include <vm/vm_kern.h> 72 #include <vm/vm_extern.h> 73 #include <vm/vm_map.h> 74 #include <vm/vm_page.h> 75 #include <vm/uma.h> 76 #include <vm/uma_int.h> 77 #include <vm/uma_dbg.h> 78 79 #ifdef DEBUG_MEMGUARD 80 #include <vm/memguard.h> 81 #endif 82 #ifdef DEBUG_REDZONE 83 #include <vm/redzone.h> 84 #endif 85 86 #if defined(INVARIANTS) && defined(__i386__) 87 #include <machine/cpu.h> 88 #endif 89 90 #include <ddb/ddb.h> 91 92 #ifdef KDTRACE_HOOKS 93 #include <sys/dtrace_bsd.h> 94 95 dtrace_malloc_probe_func_t dtrace_malloc_probe; 96 #endif 97 98 /* 99 * When realloc() is called, if the new size is sufficiently smaller than 100 * the old size, realloc() will allocate a new, smaller block to avoid 101 * wasting memory. 'Sufficiently smaller' is defined as: newsize <= 102 * oldsize / 2^n, where REALLOC_FRACTION defines the value of 'n'. 103 */ 104 #ifndef REALLOC_FRACTION 105 #define REALLOC_FRACTION 1 /* new block if <= half the size */ 106 #endif 107 108 /* 109 * Centrally define some common malloc types. 110 */ 111 MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches"); 112 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); 113 MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers"); 114 115 static struct malloc_type *kmemstatistics; 116 static int kmemcount; 117 118 #define KMEM_ZSHIFT 4 119 #define KMEM_ZBASE 16 120 #define KMEM_ZMASK (KMEM_ZBASE - 1) 121 122 #define KMEM_ZMAX 65536 123 #define KMEM_ZSIZE (KMEM_ZMAX >> KMEM_ZSHIFT) 124 static uint8_t kmemsize[KMEM_ZSIZE + 1]; 125 126 #ifndef MALLOC_DEBUG_MAXZONES 127 #define MALLOC_DEBUG_MAXZONES 1 128 #endif 129 static int numzones = MALLOC_DEBUG_MAXZONES; 130 131 /* 132 * Small malloc(9) memory allocations are allocated from a set of UMA buckets 133 * of various sizes. 134 * 135 * XXX: The comment here used to read "These won't be powers of two for 136 * long." It's possible that a significant amount of wasted memory could be 137 * recovered by tuning the sizes of these buckets. 138 */ 139 struct { 140 int kz_size; 141 char *kz_name; 142 uma_zone_t kz_zone[MALLOC_DEBUG_MAXZONES]; 143 } kmemzones[] = { 144 {16, "16", }, 145 {32, "32", }, 146 {64, "64", }, 147 {128, "128", }, 148 {256, "256", }, 149 {512, "512", }, 150 {1024, "1024", }, 151 {2048, "2048", }, 152 {4096, "4096", }, 153 {8192, "8192", }, 154 {16384, "16384", }, 155 {32768, "32768", }, 156 {65536, "65536", }, 157 {0, NULL}, 158 }; 159 160 /* 161 * Zone to allocate malloc type descriptions from. For ABI reasons, memory 162 * types are described by a data structure passed by the declaring code, but 163 * the malloc(9) implementation has its own data structure describing the 164 * type and statistics. This permits the malloc(9)-internal data structures 165 * to be modified without breaking binary-compiled kernel modules that 166 * declare malloc types. 167 */ 168 static uma_zone_t mt_zone; 169 170 u_long vm_kmem_size; 171 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size, CTLFLAG_RDTUN, &vm_kmem_size, 0, 172 "Size of kernel memory"); 173 174 static u_long kmem_zmax = KMEM_ZMAX; 175 SYSCTL_ULONG(_vm, OID_AUTO, kmem_zmax, CTLFLAG_RDTUN, &kmem_zmax, 0, 176 "Maximum allocation size that malloc(9) would use UMA as backend"); 177 178 static u_long vm_kmem_size_min; 179 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_min, CTLFLAG_RDTUN, &vm_kmem_size_min, 0, 180 "Minimum size of kernel memory"); 181 182 static u_long vm_kmem_size_max; 183 SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RDTUN, &vm_kmem_size_max, 0, 184 "Maximum size of kernel memory"); 185 186 static u_int vm_kmem_size_scale; 187 SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RDTUN, &vm_kmem_size_scale, 0, 188 "Scale factor for kernel memory size"); 189 190 static int sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS); 191 SYSCTL_PROC(_vm, OID_AUTO, kmem_map_size, 192 CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, 193 sysctl_kmem_map_size, "LU", "Current kmem allocation size"); 194 195 static int sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS); 196 SYSCTL_PROC(_vm, OID_AUTO, kmem_map_free, 197 CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0, 198 sysctl_kmem_map_free, "LU", "Free space in kmem"); 199 200 /* 201 * The malloc_mtx protects the kmemstatistics linked list. 202 */ 203 struct mtx malloc_mtx; 204 205 #ifdef MALLOC_PROFILE 206 uint64_t krequests[KMEM_ZSIZE + 1]; 207 208 static int sysctl_kern_mprof(SYSCTL_HANDLER_ARGS); 209 #endif 210 211 static int sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS); 212 213 /* 214 * time_uptime of the last malloc(9) failure (induced or real). 215 */ 216 static time_t t_malloc_fail; 217 218 #if defined(MALLOC_MAKE_FAILURES) || (MALLOC_DEBUG_MAXZONES > 1) 219 static SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD, 0, 220 "Kernel malloc debugging options"); 221 #endif 222 223 /* 224 * malloc(9) fault injection -- cause malloc failures every (n) mallocs when 225 * the caller specifies M_NOWAIT. If set to 0, no failures are caused. 226 */ 227 #ifdef MALLOC_MAKE_FAILURES 228 static int malloc_failure_rate; 229 static int malloc_nowait_count; 230 static int malloc_failure_count; 231 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RWTUN, 232 &malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail"); 233 SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD, 234 &malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures"); 235 #endif 236 237 static int 238 sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS) 239 { 240 u_long size; 241 242 size = uma_size(); 243 return (sysctl_handle_long(oidp, &size, 0, req)); 244 } 245 246 static int 247 sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS) 248 { 249 u_long size, limit; 250 251 /* The sysctl is unsigned, implement as a saturation value. */ 252 size = uma_size(); 253 limit = uma_limit(); 254 if (size > limit) 255 size = 0; 256 else 257 size = limit - size; 258 return (sysctl_handle_long(oidp, &size, 0, req)); 259 } 260 261 /* 262 * malloc(9) uma zone separation -- sub-page buffer overruns in one 263 * malloc type will affect only a subset of other malloc types. 264 */ 265 #if MALLOC_DEBUG_MAXZONES > 1 266 static void 267 tunable_set_numzones(void) 268 { 269 270 TUNABLE_INT_FETCH("debug.malloc.numzones", 271 &numzones); 272 273 /* Sanity check the number of malloc uma zones. */ 274 if (numzones <= 0) 275 numzones = 1; 276 if (numzones > MALLOC_DEBUG_MAXZONES) 277 numzones = MALLOC_DEBUG_MAXZONES; 278 } 279 SYSINIT(numzones, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_set_numzones, NULL); 280 SYSCTL_INT(_debug_malloc, OID_AUTO, numzones, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 281 &numzones, 0, "Number of malloc uma subzones"); 282 283 /* 284 * Any number that changes regularly is an okay choice for the 285 * offset. Build numbers are pretty good of you have them. 286 */ 287 static u_int zone_offset = __FreeBSD_version; 288 TUNABLE_INT("debug.malloc.zone_offset", &zone_offset); 289 SYSCTL_UINT(_debug_malloc, OID_AUTO, zone_offset, CTLFLAG_RDTUN, 290 &zone_offset, 0, "Separate malloc types by examining the " 291 "Nth character in the malloc type short description."); 292 293 static u_int 294 mtp_get_subzone(const char *desc) 295 { 296 size_t len; 297 u_int val; 298 299 if (desc == NULL || (len = strlen(desc)) == 0) 300 return (0); 301 val = desc[zone_offset % len]; 302 return (val % numzones); 303 } 304 #elif MALLOC_DEBUG_MAXZONES == 0 305 #error "MALLOC_DEBUG_MAXZONES must be positive." 306 #else 307 static inline u_int 308 mtp_get_subzone(const char *desc) 309 { 310 311 return (0); 312 } 313 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 314 315 int 316 malloc_last_fail(void) 317 { 318 319 return (time_uptime - t_malloc_fail); 320 } 321 322 /* 323 * An allocation has succeeded -- update malloc type statistics for the 324 * amount of bucket size. Occurs within a critical section so that the 325 * thread isn't preempted and doesn't migrate while updating per-PCU 326 * statistics. 327 */ 328 static void 329 malloc_type_zone_allocated(struct malloc_type *mtp, unsigned long size, 330 int zindx) 331 { 332 struct malloc_type_internal *mtip; 333 struct malloc_type_stats *mtsp; 334 335 critical_enter(); 336 mtip = mtp->ks_handle; 337 mtsp = &mtip->mti_stats[curcpu]; 338 if (size > 0) { 339 mtsp->mts_memalloced += size; 340 mtsp->mts_numallocs++; 341 } 342 if (zindx != -1) 343 mtsp->mts_size |= 1 << zindx; 344 345 #ifdef KDTRACE_HOOKS 346 if (dtrace_malloc_probe != NULL) { 347 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_MALLOC]; 348 if (probe_id != 0) 349 (dtrace_malloc_probe)(probe_id, 350 (uintptr_t) mtp, (uintptr_t) mtip, 351 (uintptr_t) mtsp, size, zindx); 352 } 353 #endif 354 355 critical_exit(); 356 } 357 358 void 359 malloc_type_allocated(struct malloc_type *mtp, unsigned long size) 360 { 361 362 if (size > 0) 363 malloc_type_zone_allocated(mtp, size, -1); 364 } 365 366 /* 367 * A free operation has occurred -- update malloc type statistics for the 368 * amount of the bucket size. Occurs within a critical section so that the 369 * thread isn't preempted and doesn't migrate while updating per-CPU 370 * statistics. 371 */ 372 void 373 malloc_type_freed(struct malloc_type *mtp, unsigned long size) 374 { 375 struct malloc_type_internal *mtip; 376 struct malloc_type_stats *mtsp; 377 378 critical_enter(); 379 mtip = mtp->ks_handle; 380 mtsp = &mtip->mti_stats[curcpu]; 381 mtsp->mts_memfreed += size; 382 mtsp->mts_numfrees++; 383 384 #ifdef KDTRACE_HOOKS 385 if (dtrace_malloc_probe != NULL) { 386 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_FREE]; 387 if (probe_id != 0) 388 (dtrace_malloc_probe)(probe_id, 389 (uintptr_t) mtp, (uintptr_t) mtip, 390 (uintptr_t) mtsp, size, 0); 391 } 392 #endif 393 394 critical_exit(); 395 } 396 397 /* 398 * contigmalloc: 399 * 400 * Allocate a block of physically contiguous memory. 401 * 402 * If M_NOWAIT is set, this routine will not block and return NULL if 403 * the allocation fails. 404 */ 405 void * 406 contigmalloc(unsigned long size, struct malloc_type *type, int flags, 407 vm_paddr_t low, vm_paddr_t high, unsigned long alignment, 408 vm_paddr_t boundary) 409 { 410 void *ret; 411 412 ret = (void *)kmem_alloc_contig(kernel_arena, size, flags, low, high, 413 alignment, boundary, VM_MEMATTR_DEFAULT); 414 if (ret != NULL) 415 malloc_type_allocated(type, round_page(size)); 416 return (ret); 417 } 418 419 /* 420 * contigfree: 421 * 422 * Free a block of memory allocated by contigmalloc. 423 * 424 * This routine may not block. 425 */ 426 void 427 contigfree(void *addr, unsigned long size, struct malloc_type *type) 428 { 429 430 kmem_free(kernel_arena, (vm_offset_t)addr, size); 431 malloc_type_freed(type, round_page(size)); 432 } 433 434 /* 435 * malloc: 436 * 437 * Allocate a block of memory. 438 * 439 * If M_NOWAIT is set, this routine will not block and return NULL if 440 * the allocation fails. 441 */ 442 void * 443 malloc(unsigned long size, struct malloc_type *mtp, int flags) 444 { 445 int indx; 446 struct malloc_type_internal *mtip; 447 caddr_t va; 448 uma_zone_t zone; 449 #if defined(DIAGNOSTIC) || defined(DEBUG_REDZONE) 450 unsigned long osize = size; 451 #endif 452 453 #ifdef INVARIANTS 454 KASSERT(mtp->ks_magic == M_MAGIC, ("malloc: bad malloc type magic")); 455 /* 456 * Check that exactly one of M_WAITOK or M_NOWAIT is specified. 457 */ 458 indx = flags & (M_WAITOK | M_NOWAIT); 459 if (indx != M_NOWAIT && indx != M_WAITOK) { 460 static struct timeval lasterr; 461 static int curerr, once; 462 if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) { 463 printf("Bad malloc flags: %x\n", indx); 464 kdb_backtrace(); 465 flags |= M_WAITOK; 466 once++; 467 } 468 } 469 #endif 470 #ifdef MALLOC_MAKE_FAILURES 471 if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) { 472 atomic_add_int(&malloc_nowait_count, 1); 473 if ((malloc_nowait_count % malloc_failure_rate) == 0) { 474 atomic_add_int(&malloc_failure_count, 1); 475 t_malloc_fail = time_uptime; 476 return (NULL); 477 } 478 } 479 #endif 480 if (flags & M_WAITOK) 481 KASSERT(curthread->td_intr_nesting_level == 0, 482 ("malloc(M_WAITOK) in interrupt context")); 483 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 484 ("malloc: called with spinlock or critical section held")); 485 486 #ifdef DEBUG_MEMGUARD 487 if (memguard_cmp_mtp(mtp, size)) { 488 va = memguard_alloc(size, flags); 489 if (va != NULL) 490 return (va); 491 /* This is unfortunate but should not be fatal. */ 492 } 493 #endif 494 495 #ifdef DEBUG_REDZONE 496 size = redzone_size_ntor(size); 497 #endif 498 499 if (size <= kmem_zmax) { 500 mtip = mtp->ks_handle; 501 if (size & KMEM_ZMASK) 502 size = (size & ~KMEM_ZMASK) + KMEM_ZBASE; 503 indx = kmemsize[size >> KMEM_ZSHIFT]; 504 KASSERT(mtip->mti_zone < numzones, 505 ("mti_zone %u out of range %d", 506 mtip->mti_zone, numzones)); 507 zone = kmemzones[indx].kz_zone[mtip->mti_zone]; 508 #ifdef MALLOC_PROFILE 509 krequests[size >> KMEM_ZSHIFT]++; 510 #endif 511 va = uma_zalloc(zone, flags); 512 if (va != NULL) 513 size = zone->uz_size; 514 malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx); 515 } else { 516 size = roundup(size, PAGE_SIZE); 517 zone = NULL; 518 va = uma_large_malloc(size, flags); 519 malloc_type_allocated(mtp, va == NULL ? 0 : size); 520 } 521 if (flags & M_WAITOK) 522 KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL")); 523 else if (va == NULL) 524 t_malloc_fail = time_uptime; 525 #ifdef DIAGNOSTIC 526 if (va != NULL && !(flags & M_ZERO)) { 527 memset(va, 0x70, osize); 528 } 529 #endif 530 #ifdef DEBUG_REDZONE 531 if (va != NULL) 532 va = redzone_setup(va, osize); 533 #endif 534 return ((void *) va); 535 } 536 537 /* 538 * free: 539 * 540 * Free a block of memory allocated by malloc. 541 * 542 * This routine may not block. 543 */ 544 void 545 free(void *addr, struct malloc_type *mtp) 546 { 547 uma_slab_t slab; 548 u_long size; 549 550 KASSERT(mtp->ks_magic == M_MAGIC, ("free: bad malloc type magic")); 551 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 552 ("free: called with spinlock or critical section held")); 553 554 /* free(NULL, ...) does nothing */ 555 if (addr == NULL) 556 return; 557 558 #ifdef DEBUG_MEMGUARD 559 if (is_memguard_addr(addr)) { 560 memguard_free(addr); 561 return; 562 } 563 #endif 564 565 #ifdef DEBUG_REDZONE 566 redzone_check(addr); 567 addr = redzone_addr_ntor(addr); 568 #endif 569 570 slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK)); 571 572 if (slab == NULL) 573 panic("free: address %p(%p) has not been allocated.\n", 574 addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); 575 576 if (!(slab->us_flags & UMA_SLAB_MALLOC)) { 577 #ifdef INVARIANTS 578 struct malloc_type **mtpp = addr; 579 #endif 580 size = slab->us_keg->uk_size; 581 #ifdef INVARIANTS 582 /* 583 * Cache a pointer to the malloc_type that most recently freed 584 * this memory here. This way we know who is most likely to 585 * have stepped on it later. 586 * 587 * This code assumes that size is a multiple of 8 bytes for 588 * 64 bit machines 589 */ 590 mtpp = (struct malloc_type **) 591 ((unsigned long)mtpp & ~UMA_ALIGN_PTR); 592 mtpp += (size - sizeof(struct malloc_type *)) / 593 sizeof(struct malloc_type *); 594 *mtpp = mtp; 595 #endif 596 uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab); 597 } else { 598 size = slab->us_size; 599 uma_large_free(slab); 600 } 601 malloc_type_freed(mtp, size); 602 } 603 604 /* 605 * realloc: change the size of a memory block 606 */ 607 void * 608 realloc(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 609 { 610 uma_slab_t slab; 611 unsigned long alloc; 612 void *newaddr; 613 614 KASSERT(mtp->ks_magic == M_MAGIC, 615 ("realloc: bad malloc type magic")); 616 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 617 ("realloc: called with spinlock or critical section held")); 618 619 /* realloc(NULL, ...) is equivalent to malloc(...) */ 620 if (addr == NULL) 621 return (malloc(size, mtp, flags)); 622 623 /* 624 * XXX: Should report free of old memory and alloc of new memory to 625 * per-CPU stats. 626 */ 627 628 #ifdef DEBUG_MEMGUARD 629 if (is_memguard_addr(addr)) 630 return (memguard_realloc(addr, size, mtp, flags)); 631 #endif 632 633 #ifdef DEBUG_REDZONE 634 slab = NULL; 635 alloc = redzone_get_size(addr); 636 #else 637 slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK)); 638 639 /* Sanity check */ 640 KASSERT(slab != NULL, 641 ("realloc: address %p out of range", (void *)addr)); 642 643 /* Get the size of the original block */ 644 if (!(slab->us_flags & UMA_SLAB_MALLOC)) 645 alloc = slab->us_keg->uk_size; 646 else 647 alloc = slab->us_size; 648 649 /* Reuse the original block if appropriate */ 650 if (size <= alloc 651 && (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE)) 652 return (addr); 653 #endif /* !DEBUG_REDZONE */ 654 655 /* Allocate a new, bigger (or smaller) block */ 656 if ((newaddr = malloc(size, mtp, flags)) == NULL) 657 return (NULL); 658 659 /* Copy over original contents */ 660 bcopy(addr, newaddr, min(size, alloc)); 661 free(addr, mtp); 662 return (newaddr); 663 } 664 665 /* 666 * reallocf: same as realloc() but free memory on failure. 667 */ 668 void * 669 reallocf(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 670 { 671 void *mem; 672 673 if ((mem = realloc(addr, size, mtp, flags)) == NULL) 674 free(addr, mtp); 675 return (mem); 676 } 677 678 #ifndef __sparc64__ 679 CTASSERT(VM_KMEM_SIZE_SCALE >= 1); 680 #endif 681 682 /* 683 * Initialize the kernel memory (kmem) arena. 684 */ 685 void 686 kmeminit(void) 687 { 688 u_long mem_size; 689 u_long tmp; 690 691 #ifdef VM_KMEM_SIZE 692 if (vm_kmem_size == 0) 693 vm_kmem_size = VM_KMEM_SIZE; 694 #endif 695 #ifdef VM_KMEM_SIZE_MIN 696 if (vm_kmem_size_min == 0) 697 vm_kmem_size_min = VM_KMEM_SIZE_MIN; 698 #endif 699 #ifdef VM_KMEM_SIZE_MAX 700 if (vm_kmem_size_max == 0) 701 vm_kmem_size_max = VM_KMEM_SIZE_MAX; 702 #endif 703 /* 704 * Calculate the amount of kernel virtual address (KVA) space that is 705 * preallocated to the kmem arena. In order to support a wide range 706 * of machines, it is a function of the physical memory size, 707 * specifically, 708 * 709 * min(max(physical memory size / VM_KMEM_SIZE_SCALE, 710 * VM_KMEM_SIZE_MIN), VM_KMEM_SIZE_MAX) 711 * 712 * Every architecture must define an integral value for 713 * VM_KMEM_SIZE_SCALE. However, the definitions of VM_KMEM_SIZE_MIN 714 * and VM_KMEM_SIZE_MAX, which represent respectively the floor and 715 * ceiling on this preallocation, are optional. Typically, 716 * VM_KMEM_SIZE_MAX is itself a function of the available KVA space on 717 * a given architecture. 718 */ 719 mem_size = vm_cnt.v_page_count; 720 if (mem_size <= 32768) /* delphij XXX 128MB */ 721 kmem_zmax = PAGE_SIZE; 722 723 if (vm_kmem_size_scale < 1) 724 vm_kmem_size_scale = VM_KMEM_SIZE_SCALE; 725 726 /* 727 * Check if we should use defaults for the "vm_kmem_size" 728 * variable: 729 */ 730 if (vm_kmem_size == 0) { 731 vm_kmem_size = (mem_size / vm_kmem_size_scale) * PAGE_SIZE; 732 733 if (vm_kmem_size_min > 0 && vm_kmem_size < vm_kmem_size_min) 734 vm_kmem_size = vm_kmem_size_min; 735 if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max) 736 vm_kmem_size = vm_kmem_size_max; 737 } 738 739 /* 740 * The amount of KVA space that is preallocated to the 741 * kmem arena can be set statically at compile-time or manually 742 * through the kernel environment. However, it is still limited to 743 * twice the physical memory size, which has been sufficient to handle 744 * the most severe cases of external fragmentation in the kmem arena. 745 */ 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 uma_set_limit(tmp); 756 757 #ifdef DEBUG_MEMGUARD 758 /* 759 * Initialize MemGuard if support compiled in. MemGuard is a 760 * replacement allocator used for detecting tamper-after-free 761 * scenarios as they occur. It is only used for debugging. 762 */ 763 memguard_init(kernel_arena); 764 #endif 765 } 766 767 /* 768 * Initialize the kernel memory allocator 769 */ 770 /* ARGSUSED*/ 771 static void 772 mallocinit(void *dummy) 773 { 774 int i; 775 uint8_t indx; 776 777 mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF); 778 779 kmeminit(); 780 781 uma_startup2(); 782 783 if (kmem_zmax < PAGE_SIZE || kmem_zmax > KMEM_ZMAX) 784 kmem_zmax = KMEM_ZMAX; 785 786 mt_zone = uma_zcreate("mt_zone", sizeof(struct malloc_type_internal), 787 #ifdef INVARIANTS 788 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 789 #else 790 NULL, NULL, NULL, NULL, 791 #endif 792 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 793 for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) { 794 int size = kmemzones[indx].kz_size; 795 char *name = kmemzones[indx].kz_name; 796 int subzone; 797 798 for (subzone = 0; subzone < numzones; subzone++) { 799 kmemzones[indx].kz_zone[subzone] = 800 uma_zcreate(name, size, 801 #ifdef INVARIANTS 802 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 803 #else 804 NULL, NULL, NULL, NULL, 805 #endif 806 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 807 } 808 for (;i <= size; i+= KMEM_ZBASE) 809 kmemsize[i >> KMEM_ZSHIFT] = indx; 810 811 } 812 } 813 SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_SECOND, mallocinit, NULL); 814 815 void 816 malloc_init(void *data) 817 { 818 struct malloc_type_internal *mtip; 819 struct malloc_type *mtp; 820 821 KASSERT(vm_cnt.v_page_count != 0, ("malloc_register before vm_init")); 822 823 mtp = data; 824 if (mtp->ks_magic != M_MAGIC) 825 panic("malloc_init: bad malloc type magic"); 826 827 mtip = uma_zalloc(mt_zone, M_WAITOK | M_ZERO); 828 mtp->ks_handle = mtip; 829 mtip->mti_zone = mtp_get_subzone(mtp->ks_shortdesc); 830 831 mtx_lock(&malloc_mtx); 832 mtp->ks_next = kmemstatistics; 833 kmemstatistics = mtp; 834 kmemcount++; 835 mtx_unlock(&malloc_mtx); 836 } 837 838 void 839 malloc_uninit(void *data) 840 { 841 struct malloc_type_internal *mtip; 842 struct malloc_type_stats *mtsp; 843 struct malloc_type *mtp, *temp; 844 uma_slab_t slab; 845 long temp_allocs, temp_bytes; 846 int i; 847 848 mtp = data; 849 KASSERT(mtp->ks_magic == M_MAGIC, 850 ("malloc_uninit: bad malloc type magic")); 851 KASSERT(mtp->ks_handle != NULL, ("malloc_deregister: cookie NULL")); 852 853 mtx_lock(&malloc_mtx); 854 mtip = mtp->ks_handle; 855 mtp->ks_handle = NULL; 856 if (mtp != kmemstatistics) { 857 for (temp = kmemstatistics; temp != NULL; 858 temp = temp->ks_next) { 859 if (temp->ks_next == mtp) { 860 temp->ks_next = mtp->ks_next; 861 break; 862 } 863 } 864 KASSERT(temp, 865 ("malloc_uninit: type '%s' not found", mtp->ks_shortdesc)); 866 } else 867 kmemstatistics = mtp->ks_next; 868 kmemcount--; 869 mtx_unlock(&malloc_mtx); 870 871 /* 872 * Look for memory leaks. 873 */ 874 temp_allocs = temp_bytes = 0; 875 for (i = 0; i < MAXCPU; i++) { 876 mtsp = &mtip->mti_stats[i]; 877 temp_allocs += mtsp->mts_numallocs; 878 temp_allocs -= mtsp->mts_numfrees; 879 temp_bytes += mtsp->mts_memalloced; 880 temp_bytes -= mtsp->mts_memfreed; 881 } 882 if (temp_allocs > 0 || temp_bytes > 0) { 883 printf("Warning: memory type %s leaked memory on destroy " 884 "(%ld allocations, %ld bytes leaked).\n", mtp->ks_shortdesc, 885 temp_allocs, temp_bytes); 886 } 887 888 slab = vtoslab((vm_offset_t) mtip & (~UMA_SLAB_MASK)); 889 uma_zfree_arg(mt_zone, mtip, slab); 890 } 891 892 struct malloc_type * 893 malloc_desc2type(const char *desc) 894 { 895 struct malloc_type *mtp; 896 897 mtx_assert(&malloc_mtx, MA_OWNED); 898 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 899 if (strcmp(mtp->ks_shortdesc, desc) == 0) 900 return (mtp); 901 } 902 return (NULL); 903 } 904 905 static int 906 sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS) 907 { 908 struct malloc_type_stream_header mtsh; 909 struct malloc_type_internal *mtip; 910 struct malloc_type_header mth; 911 struct malloc_type *mtp; 912 int error, i; 913 struct sbuf sbuf; 914 915 error = sysctl_wire_old_buffer(req, 0); 916 if (error != 0) 917 return (error); 918 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 919 sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL); 920 mtx_lock(&malloc_mtx); 921 922 /* 923 * Insert stream header. 924 */ 925 bzero(&mtsh, sizeof(mtsh)); 926 mtsh.mtsh_version = MALLOC_TYPE_STREAM_VERSION; 927 mtsh.mtsh_maxcpus = MAXCPU; 928 mtsh.mtsh_count = kmemcount; 929 (void)sbuf_bcat(&sbuf, &mtsh, sizeof(mtsh)); 930 931 /* 932 * Insert alternating sequence of type headers and type statistics. 933 */ 934 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 935 mtip = (struct malloc_type_internal *)mtp->ks_handle; 936 937 /* 938 * Insert type header. 939 */ 940 bzero(&mth, sizeof(mth)); 941 strlcpy(mth.mth_name, mtp->ks_shortdesc, MALLOC_MAX_NAME); 942 (void)sbuf_bcat(&sbuf, &mth, sizeof(mth)); 943 944 /* 945 * Insert type statistics for each CPU. 946 */ 947 for (i = 0; i < MAXCPU; i++) { 948 (void)sbuf_bcat(&sbuf, &mtip->mti_stats[i], 949 sizeof(mtip->mti_stats[i])); 950 } 951 } 952 mtx_unlock(&malloc_mtx); 953 error = sbuf_finish(&sbuf); 954 sbuf_delete(&sbuf); 955 return (error); 956 } 957 958 SYSCTL_PROC(_kern, OID_AUTO, malloc_stats, CTLFLAG_RD|CTLTYPE_STRUCT, 959 0, 0, sysctl_kern_malloc_stats, "s,malloc_type_ustats", 960 "Return malloc types"); 961 962 SYSCTL_INT(_kern, OID_AUTO, malloc_count, CTLFLAG_RD, &kmemcount, 0, 963 "Count of kernel malloc types"); 964 965 void 966 malloc_type_list(malloc_type_list_func_t *func, void *arg) 967 { 968 struct malloc_type *mtp, **bufmtp; 969 int count, i; 970 size_t buflen; 971 972 mtx_lock(&malloc_mtx); 973 restart: 974 mtx_assert(&malloc_mtx, MA_OWNED); 975 count = kmemcount; 976 mtx_unlock(&malloc_mtx); 977 978 buflen = sizeof(struct malloc_type *) * count; 979 bufmtp = malloc(buflen, M_TEMP, M_WAITOK); 980 981 mtx_lock(&malloc_mtx); 982 983 if (count < kmemcount) { 984 free(bufmtp, M_TEMP); 985 goto restart; 986 } 987 988 for (mtp = kmemstatistics, i = 0; mtp != NULL; mtp = mtp->ks_next, i++) 989 bufmtp[i] = mtp; 990 991 mtx_unlock(&malloc_mtx); 992 993 for (i = 0; i < count; i++) 994 (func)(bufmtp[i], arg); 995 996 free(bufmtp, M_TEMP); 997 } 998 999 #ifdef DDB 1000 DB_SHOW_COMMAND(malloc, db_show_malloc) 1001 { 1002 struct malloc_type_internal *mtip; 1003 struct malloc_type *mtp; 1004 uint64_t allocs, frees; 1005 uint64_t alloced, freed; 1006 int i; 1007 1008 db_printf("%18s %12s %12s %12s\n", "Type", "InUse", "MemUse", 1009 "Requests"); 1010 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 1011 mtip = (struct malloc_type_internal *)mtp->ks_handle; 1012 allocs = 0; 1013 frees = 0; 1014 alloced = 0; 1015 freed = 0; 1016 for (i = 0; i < MAXCPU; i++) { 1017 allocs += mtip->mti_stats[i].mts_numallocs; 1018 frees += mtip->mti_stats[i].mts_numfrees; 1019 alloced += mtip->mti_stats[i].mts_memalloced; 1020 freed += mtip->mti_stats[i].mts_memfreed; 1021 } 1022 db_printf("%18s %12ju %12juK %12ju\n", 1023 mtp->ks_shortdesc, allocs - frees, 1024 (alloced - freed + 1023) / 1024, allocs); 1025 if (db_pager_quit) 1026 break; 1027 } 1028 } 1029 1030 #if MALLOC_DEBUG_MAXZONES > 1 1031 DB_SHOW_COMMAND(multizone_matches, db_show_multizone_matches) 1032 { 1033 struct malloc_type_internal *mtip; 1034 struct malloc_type *mtp; 1035 u_int subzone; 1036 1037 if (!have_addr) { 1038 db_printf("Usage: show multizone_matches <malloc type/addr>\n"); 1039 return; 1040 } 1041 mtp = (void *)addr; 1042 if (mtp->ks_magic != M_MAGIC) { 1043 db_printf("Magic %lx does not match expected %x\n", 1044 mtp->ks_magic, M_MAGIC); 1045 return; 1046 } 1047 1048 mtip = mtp->ks_handle; 1049 subzone = mtip->mti_zone; 1050 1051 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 1052 mtip = mtp->ks_handle; 1053 if (mtip->mti_zone != subzone) 1054 continue; 1055 db_printf("%s\n", mtp->ks_shortdesc); 1056 if (db_pager_quit) 1057 break; 1058 } 1059 } 1060 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 1061 #endif /* DDB */ 1062 1063 #ifdef MALLOC_PROFILE 1064 1065 static int 1066 sysctl_kern_mprof(SYSCTL_HANDLER_ARGS) 1067 { 1068 struct sbuf sbuf; 1069 uint64_t count; 1070 uint64_t waste; 1071 uint64_t mem; 1072 int error; 1073 int rsize; 1074 int size; 1075 int i; 1076 1077 waste = 0; 1078 mem = 0; 1079 1080 error = sysctl_wire_old_buffer(req, 0); 1081 if (error != 0) 1082 return (error); 1083 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 1084 sbuf_printf(&sbuf, 1085 "\n Size Requests Real Size\n"); 1086 for (i = 0; i < KMEM_ZSIZE; i++) { 1087 size = i << KMEM_ZSHIFT; 1088 rsize = kmemzones[kmemsize[i]].kz_size; 1089 count = (long long unsigned)krequests[i]; 1090 1091 sbuf_printf(&sbuf, "%6d%28llu%11d\n", size, 1092 (unsigned long long)count, rsize); 1093 1094 if ((rsize * count) > (size * count)) 1095 waste += (rsize * count) - (size * count); 1096 mem += (rsize * count); 1097 } 1098 sbuf_printf(&sbuf, 1099 "\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n", 1100 (unsigned long long)mem, (unsigned long long)waste); 1101 error = sbuf_finish(&sbuf); 1102 sbuf_delete(&sbuf); 1103 return (error); 1104 } 1105 1106 SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD, 1107 NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling"); 1108 #endif /* MALLOC_PROFILE */ 1109