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 = vmem_size(kmem_arena, VMEM_ALLOC); 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; 250 251 size = vmem_size(kmem_arena, VMEM_FREE); 252 return (sysctl_handle_long(oidp, &size, 0, req)); 253 } 254 255 /* 256 * malloc(9) uma zone separation -- sub-page buffer overruns in one 257 * malloc type will affect only a subset of other malloc types. 258 */ 259 #if MALLOC_DEBUG_MAXZONES > 1 260 static void 261 tunable_set_numzones(void) 262 { 263 264 TUNABLE_INT_FETCH("debug.malloc.numzones", 265 &numzones); 266 267 /* Sanity check the number of malloc uma zones. */ 268 if (numzones <= 0) 269 numzones = 1; 270 if (numzones > MALLOC_DEBUG_MAXZONES) 271 numzones = MALLOC_DEBUG_MAXZONES; 272 } 273 SYSINIT(numzones, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_set_numzones, NULL); 274 SYSCTL_INT(_debug_malloc, OID_AUTO, numzones, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 275 &numzones, 0, "Number of malloc uma subzones"); 276 277 /* 278 * Any number that changes regularly is an okay choice for the 279 * offset. Build numbers are pretty good of you have them. 280 */ 281 static u_int zone_offset = __FreeBSD_version; 282 TUNABLE_INT("debug.malloc.zone_offset", &zone_offset); 283 SYSCTL_UINT(_debug_malloc, OID_AUTO, zone_offset, CTLFLAG_RDTUN, 284 &zone_offset, 0, "Separate malloc types by examining the " 285 "Nth character in the malloc type short description."); 286 287 static u_int 288 mtp_get_subzone(const char *desc) 289 { 290 size_t len; 291 u_int val; 292 293 if (desc == NULL || (len = strlen(desc)) == 0) 294 return (0); 295 val = desc[zone_offset % len]; 296 return (val % numzones); 297 } 298 #elif MALLOC_DEBUG_MAXZONES == 0 299 #error "MALLOC_DEBUG_MAXZONES must be positive." 300 #else 301 static inline u_int 302 mtp_get_subzone(const char *desc) 303 { 304 305 return (0); 306 } 307 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 308 309 int 310 malloc_last_fail(void) 311 { 312 313 return (time_uptime - t_malloc_fail); 314 } 315 316 /* 317 * An allocation has succeeded -- update malloc type statistics for the 318 * amount of bucket size. Occurs within a critical section so that the 319 * thread isn't preempted and doesn't migrate while updating per-PCU 320 * statistics. 321 */ 322 static void 323 malloc_type_zone_allocated(struct malloc_type *mtp, unsigned long size, 324 int zindx) 325 { 326 struct malloc_type_internal *mtip; 327 struct malloc_type_stats *mtsp; 328 329 critical_enter(); 330 mtip = mtp->ks_handle; 331 mtsp = &mtip->mti_stats[curcpu]; 332 if (size > 0) { 333 mtsp->mts_memalloced += size; 334 mtsp->mts_numallocs++; 335 } 336 if (zindx != -1) 337 mtsp->mts_size |= 1 << zindx; 338 339 #ifdef KDTRACE_HOOKS 340 if (dtrace_malloc_probe != NULL) { 341 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_MALLOC]; 342 if (probe_id != 0) 343 (dtrace_malloc_probe)(probe_id, 344 (uintptr_t) mtp, (uintptr_t) mtip, 345 (uintptr_t) mtsp, size, zindx); 346 } 347 #endif 348 349 critical_exit(); 350 } 351 352 void 353 malloc_type_allocated(struct malloc_type *mtp, unsigned long size) 354 { 355 356 if (size > 0) 357 malloc_type_zone_allocated(mtp, size, -1); 358 } 359 360 /* 361 * A free operation has occurred -- update malloc type statistics for the 362 * amount of the bucket size. Occurs within a critical section so that the 363 * thread isn't preempted and doesn't migrate while updating per-CPU 364 * statistics. 365 */ 366 void 367 malloc_type_freed(struct malloc_type *mtp, unsigned long size) 368 { 369 struct malloc_type_internal *mtip; 370 struct malloc_type_stats *mtsp; 371 372 critical_enter(); 373 mtip = mtp->ks_handle; 374 mtsp = &mtip->mti_stats[curcpu]; 375 mtsp->mts_memfreed += size; 376 mtsp->mts_numfrees++; 377 378 #ifdef KDTRACE_HOOKS 379 if (dtrace_malloc_probe != NULL) { 380 uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_FREE]; 381 if (probe_id != 0) 382 (dtrace_malloc_probe)(probe_id, 383 (uintptr_t) mtp, (uintptr_t) mtip, 384 (uintptr_t) mtsp, size, 0); 385 } 386 #endif 387 388 critical_exit(); 389 } 390 391 /* 392 * contigmalloc: 393 * 394 * Allocate a block of physically contiguous memory. 395 * 396 * If M_NOWAIT is set, this routine will not block and return NULL if 397 * the allocation fails. 398 */ 399 void * 400 contigmalloc(unsigned long size, struct malloc_type *type, int flags, 401 vm_paddr_t low, vm_paddr_t high, unsigned long alignment, 402 vm_paddr_t boundary) 403 { 404 void *ret; 405 406 ret = (void *)kmem_alloc_contig(kernel_arena, size, flags, low, high, 407 alignment, boundary, VM_MEMATTR_DEFAULT); 408 if (ret != NULL) 409 malloc_type_allocated(type, round_page(size)); 410 return (ret); 411 } 412 413 /* 414 * contigfree: 415 * 416 * Free a block of memory allocated by contigmalloc. 417 * 418 * This routine may not block. 419 */ 420 void 421 contigfree(void *addr, unsigned long size, struct malloc_type *type) 422 { 423 424 kmem_free(kernel_arena, (vm_offset_t)addr, size); 425 malloc_type_freed(type, round_page(size)); 426 } 427 428 /* 429 * malloc: 430 * 431 * Allocate a block of memory. 432 * 433 * If M_NOWAIT is set, this routine will not block and return NULL if 434 * the allocation fails. 435 */ 436 void * 437 malloc(unsigned long size, struct malloc_type *mtp, int flags) 438 { 439 int indx; 440 struct malloc_type_internal *mtip; 441 caddr_t va; 442 uma_zone_t zone; 443 #if defined(DIAGNOSTIC) || defined(DEBUG_REDZONE) 444 unsigned long osize = size; 445 #endif 446 447 #ifdef INVARIANTS 448 KASSERT(mtp->ks_magic == M_MAGIC, ("malloc: bad malloc type magic")); 449 /* 450 * Check that exactly one of M_WAITOK or M_NOWAIT is specified. 451 */ 452 indx = flags & (M_WAITOK | M_NOWAIT); 453 if (indx != M_NOWAIT && indx != M_WAITOK) { 454 static struct timeval lasterr; 455 static int curerr, once; 456 if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) { 457 printf("Bad malloc flags: %x\n", indx); 458 kdb_backtrace(); 459 flags |= M_WAITOK; 460 once++; 461 } 462 } 463 #endif 464 #ifdef MALLOC_MAKE_FAILURES 465 if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) { 466 atomic_add_int(&malloc_nowait_count, 1); 467 if ((malloc_nowait_count % malloc_failure_rate) == 0) { 468 atomic_add_int(&malloc_failure_count, 1); 469 t_malloc_fail = time_uptime; 470 return (NULL); 471 } 472 } 473 #endif 474 if (flags & M_WAITOK) 475 KASSERT(curthread->td_intr_nesting_level == 0, 476 ("malloc(M_WAITOK) in interrupt context")); 477 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 478 ("malloc: called with spinlock or critical section held")); 479 480 #ifdef DEBUG_MEMGUARD 481 if (memguard_cmp_mtp(mtp, size)) { 482 va = memguard_alloc(size, flags); 483 if (va != NULL) 484 return (va); 485 /* This is unfortunate but should not be fatal. */ 486 } 487 #endif 488 489 #ifdef DEBUG_REDZONE 490 size = redzone_size_ntor(size); 491 #endif 492 493 if (size <= kmem_zmax) { 494 mtip = mtp->ks_handle; 495 if (size & KMEM_ZMASK) 496 size = (size & ~KMEM_ZMASK) + KMEM_ZBASE; 497 indx = kmemsize[size >> KMEM_ZSHIFT]; 498 KASSERT(mtip->mti_zone < numzones, 499 ("mti_zone %u out of range %d", 500 mtip->mti_zone, numzones)); 501 zone = kmemzones[indx].kz_zone[mtip->mti_zone]; 502 #ifdef MALLOC_PROFILE 503 krequests[size >> KMEM_ZSHIFT]++; 504 #endif 505 va = uma_zalloc(zone, flags); 506 if (va != NULL) 507 size = zone->uz_size; 508 malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx); 509 } else { 510 size = roundup(size, PAGE_SIZE); 511 zone = NULL; 512 va = uma_large_malloc(size, flags); 513 malloc_type_allocated(mtp, va == NULL ? 0 : size); 514 } 515 if (flags & M_WAITOK) 516 KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL")); 517 else if (va == NULL) 518 t_malloc_fail = time_uptime; 519 #ifdef DIAGNOSTIC 520 if (va != NULL && !(flags & M_ZERO)) { 521 memset(va, 0x70, osize); 522 } 523 #endif 524 #ifdef DEBUG_REDZONE 525 if (va != NULL) 526 va = redzone_setup(va, osize); 527 #endif 528 return ((void *) va); 529 } 530 531 /* 532 * free: 533 * 534 * Free a block of memory allocated by malloc. 535 * 536 * This routine may not block. 537 */ 538 void 539 free(void *addr, struct malloc_type *mtp) 540 { 541 uma_slab_t slab; 542 u_long size; 543 544 KASSERT(mtp->ks_magic == M_MAGIC, ("free: bad malloc type magic")); 545 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 546 ("free: called with spinlock or critical section held")); 547 548 /* free(NULL, ...) does nothing */ 549 if (addr == NULL) 550 return; 551 552 #ifdef DEBUG_MEMGUARD 553 if (is_memguard_addr(addr)) { 554 memguard_free(addr); 555 return; 556 } 557 #endif 558 559 #ifdef DEBUG_REDZONE 560 redzone_check(addr); 561 addr = redzone_addr_ntor(addr); 562 #endif 563 564 slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK)); 565 566 if (slab == NULL) 567 panic("free: address %p(%p) has not been allocated.\n", 568 addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); 569 570 if (!(slab->us_flags & UMA_SLAB_MALLOC)) { 571 #ifdef INVARIANTS 572 struct malloc_type **mtpp = addr; 573 #endif 574 size = slab->us_keg->uk_size; 575 #ifdef INVARIANTS 576 /* 577 * Cache a pointer to the malloc_type that most recently freed 578 * this memory here. This way we know who is most likely to 579 * have stepped on it later. 580 * 581 * This code assumes that size is a multiple of 8 bytes for 582 * 64 bit machines 583 */ 584 mtpp = (struct malloc_type **) 585 ((unsigned long)mtpp & ~UMA_ALIGN_PTR); 586 mtpp += (size - sizeof(struct malloc_type *)) / 587 sizeof(struct malloc_type *); 588 *mtpp = mtp; 589 #endif 590 uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab); 591 } else { 592 size = slab->us_size; 593 uma_large_free(slab); 594 } 595 malloc_type_freed(mtp, size); 596 } 597 598 /* 599 * realloc: change the size of a memory block 600 */ 601 void * 602 realloc(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 603 { 604 uma_slab_t slab; 605 unsigned long alloc; 606 void *newaddr; 607 608 KASSERT(mtp->ks_magic == M_MAGIC, 609 ("realloc: bad malloc type magic")); 610 KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(), 611 ("realloc: called with spinlock or critical section held")); 612 613 /* realloc(NULL, ...) is equivalent to malloc(...) */ 614 if (addr == NULL) 615 return (malloc(size, mtp, flags)); 616 617 /* 618 * XXX: Should report free of old memory and alloc of new memory to 619 * per-CPU stats. 620 */ 621 622 #ifdef DEBUG_MEMGUARD 623 if (is_memguard_addr(addr)) 624 return (memguard_realloc(addr, size, mtp, flags)); 625 #endif 626 627 #ifdef DEBUG_REDZONE 628 slab = NULL; 629 alloc = redzone_get_size(addr); 630 #else 631 slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK)); 632 633 /* Sanity check */ 634 KASSERT(slab != NULL, 635 ("realloc: address %p out of range", (void *)addr)); 636 637 /* Get the size of the original block */ 638 if (!(slab->us_flags & UMA_SLAB_MALLOC)) 639 alloc = slab->us_keg->uk_size; 640 else 641 alloc = slab->us_size; 642 643 /* Reuse the original block if appropriate */ 644 if (size <= alloc 645 && (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE)) 646 return (addr); 647 #endif /* !DEBUG_REDZONE */ 648 649 /* Allocate a new, bigger (or smaller) block */ 650 if ((newaddr = malloc(size, mtp, flags)) == NULL) 651 return (NULL); 652 653 /* Copy over original contents */ 654 bcopy(addr, newaddr, min(size, alloc)); 655 free(addr, mtp); 656 return (newaddr); 657 } 658 659 /* 660 * reallocf: same as realloc() but free memory on failure. 661 */ 662 void * 663 reallocf(void *addr, unsigned long size, struct malloc_type *mtp, int flags) 664 { 665 void *mem; 666 667 if ((mem = realloc(addr, size, mtp, flags)) == NULL) 668 free(addr, mtp); 669 return (mem); 670 } 671 672 /* 673 * Wake the uma reclamation pagedaemon thread when we exhaust KVA. It 674 * will call the lowmem handler and uma_reclaim() callbacks in a 675 * context that is safe. 676 */ 677 static void 678 kmem_reclaim(vmem_t *vm, int flags) 679 { 680 681 uma_reclaim_wakeup(); 682 pagedaemon_wakeup(); 683 } 684 685 #ifndef __sparc64__ 686 CTASSERT(VM_KMEM_SIZE_SCALE >= 1); 687 #endif 688 689 /* 690 * Initialize the kernel memory (kmem) arena. 691 */ 692 void 693 kmeminit(void) 694 { 695 u_long mem_size; 696 u_long tmp; 697 698 #ifdef VM_KMEM_SIZE 699 if (vm_kmem_size == 0) 700 vm_kmem_size = VM_KMEM_SIZE; 701 #endif 702 #ifdef VM_KMEM_SIZE_MIN 703 if (vm_kmem_size_min == 0) 704 vm_kmem_size_min = VM_KMEM_SIZE_MIN; 705 #endif 706 #ifdef VM_KMEM_SIZE_MAX 707 if (vm_kmem_size_max == 0) 708 vm_kmem_size_max = VM_KMEM_SIZE_MAX; 709 #endif 710 /* 711 * Calculate the amount of kernel virtual address (KVA) space that is 712 * preallocated to the kmem arena. In order to support a wide range 713 * of machines, it is a function of the physical memory size, 714 * specifically, 715 * 716 * min(max(physical memory size / VM_KMEM_SIZE_SCALE, 717 * VM_KMEM_SIZE_MIN), VM_KMEM_SIZE_MAX) 718 * 719 * Every architecture must define an integral value for 720 * VM_KMEM_SIZE_SCALE. However, the definitions of VM_KMEM_SIZE_MIN 721 * and VM_KMEM_SIZE_MAX, which represent respectively the floor and 722 * ceiling on this preallocation, are optional. Typically, 723 * VM_KMEM_SIZE_MAX is itself a function of the available KVA space on 724 * a given architecture. 725 */ 726 mem_size = vm_cnt.v_page_count; 727 if (mem_size <= 32768) /* delphij XXX 128MB */ 728 kmem_zmax = PAGE_SIZE; 729 730 if (vm_kmem_size_scale < 1) 731 vm_kmem_size_scale = VM_KMEM_SIZE_SCALE; 732 733 /* 734 * Check if we should use defaults for the "vm_kmem_size" 735 * variable: 736 */ 737 if (vm_kmem_size == 0) { 738 vm_kmem_size = (mem_size / vm_kmem_size_scale) * PAGE_SIZE; 739 740 if (vm_kmem_size_min > 0 && vm_kmem_size < vm_kmem_size_min) 741 vm_kmem_size = vm_kmem_size_min; 742 if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max) 743 vm_kmem_size = vm_kmem_size_max; 744 } 745 746 /* 747 * The amount of KVA space that is preallocated to the 748 * kmem arena can be set statically at compile-time or manually 749 * through the kernel environment. However, it is still limited to 750 * twice the physical memory size, which has been sufficient to handle 751 * the most severe cases of external fragmentation in the kmem arena. 752 */ 753 if (vm_kmem_size / 2 / PAGE_SIZE > mem_size) 754 vm_kmem_size = 2 * mem_size * PAGE_SIZE; 755 756 vm_kmem_size = round_page(vm_kmem_size); 757 #ifdef DEBUG_MEMGUARD 758 tmp = memguard_fudge(vm_kmem_size, kernel_map); 759 #else 760 tmp = vm_kmem_size; 761 #endif 762 vmem_init(kmem_arena, "kmem arena", kva_alloc(tmp), tmp, PAGE_SIZE, 763 0, 0); 764 vmem_set_reclaim(kmem_arena, kmem_reclaim); 765 766 #ifdef DEBUG_MEMGUARD 767 /* 768 * Initialize MemGuard if support compiled in. MemGuard is a 769 * replacement allocator used for detecting tamper-after-free 770 * scenarios as they occur. It is only used for debugging. 771 */ 772 memguard_init(kmem_arena); 773 #endif 774 } 775 776 /* 777 * Initialize the kernel memory allocator 778 */ 779 /* ARGSUSED*/ 780 static void 781 mallocinit(void *dummy) 782 { 783 int i; 784 uint8_t indx; 785 786 mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF); 787 788 kmeminit(); 789 790 uma_startup2(); 791 792 if (kmem_zmax < PAGE_SIZE || kmem_zmax > KMEM_ZMAX) 793 kmem_zmax = KMEM_ZMAX; 794 795 mt_zone = uma_zcreate("mt_zone", sizeof(struct malloc_type_internal), 796 #ifdef INVARIANTS 797 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 798 #else 799 NULL, NULL, NULL, NULL, 800 #endif 801 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 802 for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) { 803 int size = kmemzones[indx].kz_size; 804 char *name = kmemzones[indx].kz_name; 805 int subzone; 806 807 for (subzone = 0; subzone < numzones; subzone++) { 808 kmemzones[indx].kz_zone[subzone] = 809 uma_zcreate(name, size, 810 #ifdef INVARIANTS 811 mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini, 812 #else 813 NULL, NULL, NULL, NULL, 814 #endif 815 UMA_ALIGN_PTR, UMA_ZONE_MALLOC); 816 } 817 for (;i <= size; i+= KMEM_ZBASE) 818 kmemsize[i >> KMEM_ZSHIFT] = indx; 819 820 } 821 } 822 SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_SECOND, mallocinit, NULL); 823 824 void 825 malloc_init(void *data) 826 { 827 struct malloc_type_internal *mtip; 828 struct malloc_type *mtp; 829 830 KASSERT(vm_cnt.v_page_count != 0, ("malloc_register before vm_init")); 831 832 mtp = data; 833 if (mtp->ks_magic != M_MAGIC) 834 panic("malloc_init: bad malloc type magic"); 835 836 mtip = uma_zalloc(mt_zone, M_WAITOK | M_ZERO); 837 mtp->ks_handle = mtip; 838 mtip->mti_zone = mtp_get_subzone(mtp->ks_shortdesc); 839 840 mtx_lock(&malloc_mtx); 841 mtp->ks_next = kmemstatistics; 842 kmemstatistics = mtp; 843 kmemcount++; 844 mtx_unlock(&malloc_mtx); 845 } 846 847 void 848 malloc_uninit(void *data) 849 { 850 struct malloc_type_internal *mtip; 851 struct malloc_type_stats *mtsp; 852 struct malloc_type *mtp, *temp; 853 uma_slab_t slab; 854 long temp_allocs, temp_bytes; 855 int i; 856 857 mtp = data; 858 KASSERT(mtp->ks_magic == M_MAGIC, 859 ("malloc_uninit: bad malloc type magic")); 860 KASSERT(mtp->ks_handle != NULL, ("malloc_deregister: cookie NULL")); 861 862 mtx_lock(&malloc_mtx); 863 mtip = mtp->ks_handle; 864 mtp->ks_handle = NULL; 865 if (mtp != kmemstatistics) { 866 for (temp = kmemstatistics; temp != NULL; 867 temp = temp->ks_next) { 868 if (temp->ks_next == mtp) { 869 temp->ks_next = mtp->ks_next; 870 break; 871 } 872 } 873 KASSERT(temp, 874 ("malloc_uninit: type '%s' not found", mtp->ks_shortdesc)); 875 } else 876 kmemstatistics = mtp->ks_next; 877 kmemcount--; 878 mtx_unlock(&malloc_mtx); 879 880 /* 881 * Look for memory leaks. 882 */ 883 temp_allocs = temp_bytes = 0; 884 for (i = 0; i < MAXCPU; i++) { 885 mtsp = &mtip->mti_stats[i]; 886 temp_allocs += mtsp->mts_numallocs; 887 temp_allocs -= mtsp->mts_numfrees; 888 temp_bytes += mtsp->mts_memalloced; 889 temp_bytes -= mtsp->mts_memfreed; 890 } 891 if (temp_allocs > 0 || temp_bytes > 0) { 892 printf("Warning: memory type %s leaked memory on destroy " 893 "(%ld allocations, %ld bytes leaked).\n", mtp->ks_shortdesc, 894 temp_allocs, temp_bytes); 895 } 896 897 slab = vtoslab((vm_offset_t) mtip & (~UMA_SLAB_MASK)); 898 uma_zfree_arg(mt_zone, mtip, slab); 899 } 900 901 struct malloc_type * 902 malloc_desc2type(const char *desc) 903 { 904 struct malloc_type *mtp; 905 906 mtx_assert(&malloc_mtx, MA_OWNED); 907 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 908 if (strcmp(mtp->ks_shortdesc, desc) == 0) 909 return (mtp); 910 } 911 return (NULL); 912 } 913 914 static int 915 sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS) 916 { 917 struct malloc_type_stream_header mtsh; 918 struct malloc_type_internal *mtip; 919 struct malloc_type_header mth; 920 struct malloc_type *mtp; 921 int error, i; 922 struct sbuf sbuf; 923 924 error = sysctl_wire_old_buffer(req, 0); 925 if (error != 0) 926 return (error); 927 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 928 sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL); 929 mtx_lock(&malloc_mtx); 930 931 /* 932 * Insert stream header. 933 */ 934 bzero(&mtsh, sizeof(mtsh)); 935 mtsh.mtsh_version = MALLOC_TYPE_STREAM_VERSION; 936 mtsh.mtsh_maxcpus = MAXCPU; 937 mtsh.mtsh_count = kmemcount; 938 (void)sbuf_bcat(&sbuf, &mtsh, sizeof(mtsh)); 939 940 /* 941 * Insert alternating sequence of type headers and type statistics. 942 */ 943 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 944 mtip = (struct malloc_type_internal *)mtp->ks_handle; 945 946 /* 947 * Insert type header. 948 */ 949 bzero(&mth, sizeof(mth)); 950 strlcpy(mth.mth_name, mtp->ks_shortdesc, MALLOC_MAX_NAME); 951 (void)sbuf_bcat(&sbuf, &mth, sizeof(mth)); 952 953 /* 954 * Insert type statistics for each CPU. 955 */ 956 for (i = 0; i < MAXCPU; i++) { 957 (void)sbuf_bcat(&sbuf, &mtip->mti_stats[i], 958 sizeof(mtip->mti_stats[i])); 959 } 960 } 961 mtx_unlock(&malloc_mtx); 962 error = sbuf_finish(&sbuf); 963 sbuf_delete(&sbuf); 964 return (error); 965 } 966 967 SYSCTL_PROC(_kern, OID_AUTO, malloc_stats, CTLFLAG_RD|CTLTYPE_STRUCT, 968 0, 0, sysctl_kern_malloc_stats, "s,malloc_type_ustats", 969 "Return malloc types"); 970 971 SYSCTL_INT(_kern, OID_AUTO, malloc_count, CTLFLAG_RD, &kmemcount, 0, 972 "Count of kernel malloc types"); 973 974 void 975 malloc_type_list(malloc_type_list_func_t *func, void *arg) 976 { 977 struct malloc_type *mtp, **bufmtp; 978 int count, i; 979 size_t buflen; 980 981 mtx_lock(&malloc_mtx); 982 restart: 983 mtx_assert(&malloc_mtx, MA_OWNED); 984 count = kmemcount; 985 mtx_unlock(&malloc_mtx); 986 987 buflen = sizeof(struct malloc_type *) * count; 988 bufmtp = malloc(buflen, M_TEMP, M_WAITOK); 989 990 mtx_lock(&malloc_mtx); 991 992 if (count < kmemcount) { 993 free(bufmtp, M_TEMP); 994 goto restart; 995 } 996 997 for (mtp = kmemstatistics, i = 0; mtp != NULL; mtp = mtp->ks_next, i++) 998 bufmtp[i] = mtp; 999 1000 mtx_unlock(&malloc_mtx); 1001 1002 for (i = 0; i < count; i++) 1003 (func)(bufmtp[i], arg); 1004 1005 free(bufmtp, M_TEMP); 1006 } 1007 1008 #ifdef DDB 1009 DB_SHOW_COMMAND(malloc, db_show_malloc) 1010 { 1011 struct malloc_type_internal *mtip; 1012 struct malloc_type *mtp; 1013 uint64_t allocs, frees; 1014 uint64_t alloced, freed; 1015 int i; 1016 1017 db_printf("%18s %12s %12s %12s\n", "Type", "InUse", "MemUse", 1018 "Requests"); 1019 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 1020 mtip = (struct malloc_type_internal *)mtp->ks_handle; 1021 allocs = 0; 1022 frees = 0; 1023 alloced = 0; 1024 freed = 0; 1025 for (i = 0; i < MAXCPU; i++) { 1026 allocs += mtip->mti_stats[i].mts_numallocs; 1027 frees += mtip->mti_stats[i].mts_numfrees; 1028 alloced += mtip->mti_stats[i].mts_memalloced; 1029 freed += mtip->mti_stats[i].mts_memfreed; 1030 } 1031 db_printf("%18s %12ju %12juK %12ju\n", 1032 mtp->ks_shortdesc, allocs - frees, 1033 (alloced - freed + 1023) / 1024, allocs); 1034 if (db_pager_quit) 1035 break; 1036 } 1037 } 1038 1039 #if MALLOC_DEBUG_MAXZONES > 1 1040 DB_SHOW_COMMAND(multizone_matches, db_show_multizone_matches) 1041 { 1042 struct malloc_type_internal *mtip; 1043 struct malloc_type *mtp; 1044 u_int subzone; 1045 1046 if (!have_addr) { 1047 db_printf("Usage: show multizone_matches <malloc type/addr>\n"); 1048 return; 1049 } 1050 mtp = (void *)addr; 1051 if (mtp->ks_magic != M_MAGIC) { 1052 db_printf("Magic %lx does not match expected %x\n", 1053 mtp->ks_magic, M_MAGIC); 1054 return; 1055 } 1056 1057 mtip = mtp->ks_handle; 1058 subzone = mtip->mti_zone; 1059 1060 for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) { 1061 mtip = mtp->ks_handle; 1062 if (mtip->mti_zone != subzone) 1063 continue; 1064 db_printf("%s\n", mtp->ks_shortdesc); 1065 if (db_pager_quit) 1066 break; 1067 } 1068 } 1069 #endif /* MALLOC_DEBUG_MAXZONES > 1 */ 1070 #endif /* DDB */ 1071 1072 #ifdef MALLOC_PROFILE 1073 1074 static int 1075 sysctl_kern_mprof(SYSCTL_HANDLER_ARGS) 1076 { 1077 struct sbuf sbuf; 1078 uint64_t count; 1079 uint64_t waste; 1080 uint64_t mem; 1081 int error; 1082 int rsize; 1083 int size; 1084 int i; 1085 1086 waste = 0; 1087 mem = 0; 1088 1089 error = sysctl_wire_old_buffer(req, 0); 1090 if (error != 0) 1091 return (error); 1092 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 1093 sbuf_printf(&sbuf, 1094 "\n Size Requests Real Size\n"); 1095 for (i = 0; i < KMEM_ZSIZE; i++) { 1096 size = i << KMEM_ZSHIFT; 1097 rsize = kmemzones[kmemsize[i]].kz_size; 1098 count = (long long unsigned)krequests[i]; 1099 1100 sbuf_printf(&sbuf, "%6d%28llu%11d\n", size, 1101 (unsigned long long)count, rsize); 1102 1103 if ((rsize * count) > (size * count)) 1104 waste += (rsize * count) - (size * count); 1105 mem += (rsize * count); 1106 } 1107 sbuf_printf(&sbuf, 1108 "\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n", 1109 (unsigned long long)mem, (unsigned long long)waste); 1110 error = sbuf_finish(&sbuf); 1111 sbuf_delete(&sbuf); 1112 return (error); 1113 } 1114 1115 SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD, 1116 NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling"); 1117 #endif /* MALLOC_PROFILE */ 1118