| 1 | /* |
| 2 | * (MPSAFE) |
| 3 | * |
| 4 | * KERN_SLABALLOC.C - Kernel SLAB memory allocator |
| 5 | * |
| 6 | * Copyright (c) 2003,2004,2010 The DragonFly Project. All rights reserved. |
| 7 | * |
| 8 | * This code is derived from software contributed to The DragonFly Project |
| 9 | * by Matthew Dillon <dillon@backplane.com> |
| 10 | * |
| 11 | * Redistribution and use in source and binary forms, with or without |
| 12 | * modification, are permitted provided that the following conditions |
| 13 | * are met: |
| 14 | * |
| 15 | * 1. Redistributions of source code must retain the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer. |
| 17 | * 2. Redistributions in binary form must reproduce the above copyright |
| 18 | * notice, this list of conditions and the following disclaimer in |
| 19 | * the documentation and/or other materials provided with the |
| 20 | * distribution. |
| 21 | * 3. Neither the name of The DragonFly Project nor the names of its |
| 22 | * contributors may be used to endorse or promote products derived |
| 23 | * from this software without specific, prior written permission. |
| 24 | * |
| 25 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 26 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 27 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 28 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 29 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 30 | * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 31 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 32 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 33 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 34 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 35 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 36 | * SUCH DAMAGE. |
| 37 | * |
| 38 | * This module implements a slab allocator drop-in replacement for the |
| 39 | * kernel malloc(). |
| 40 | * |
| 41 | * A slab allocator reserves a ZONE for each chunk size, then lays the |
| 42 | * chunks out in an array within the zone. Allocation and deallocation |
| 43 | * is nearly instantanious, and fragmentation/overhead losses are limited |
| 44 | * to a fixed worst-case amount. |
| 45 | * |
| 46 | * The downside of this slab implementation is in the chunk size |
| 47 | * multiplied by the number of zones. ~80 zones * 128K = 10MB of VM per cpu. |
| 48 | * In a kernel implementation all this memory will be physical so |
| 49 | * the zone size is adjusted downward on machines with less physical |
| 50 | * memory. The upside is that overhead is bounded... this is the *worst* |
| 51 | * case overhead. |
| 52 | * |
| 53 | * Slab management is done on a per-cpu basis and no locking or mutexes |
| 54 | * are required, only a critical section. When one cpu frees memory |
| 55 | * belonging to another cpu's slab manager an asynchronous IPI message |
| 56 | * will be queued to execute the operation. In addition, both the |
| 57 | * high level slab allocator and the low level zone allocator optimize |
| 58 | * M_ZERO requests, and the slab allocator does not have to pre initialize |
| 59 | * the linked list of chunks. |
| 60 | * |
| 61 | * XXX Balancing is needed between cpus. Balance will be handled through |
| 62 | * asynchronous IPIs primarily by reassigning the z_Cpu ownership of chunks. |
| 63 | * |
| 64 | * XXX If we have to allocate a new zone and M_USE_RESERVE is set, use of |
| 65 | * the new zone should be restricted to M_USE_RESERVE requests only. |
| 66 | * |
| 67 | * Alloc Size Chunking Number of zones |
| 68 | * 0-127 8 16 |
| 69 | * 128-255 16 8 |
| 70 | * 256-511 32 8 |
| 71 | * 512-1023 64 8 |
| 72 | * 1024-2047 128 8 |
| 73 | * 2048-4095 256 8 |
| 74 | * 4096-8191 512 8 |
| 75 | * 8192-16383 1024 8 |
| 76 | * 16384-32767 2048 8 |
| 77 | * (if PAGE_SIZE is 4K the maximum zone allocation is 16383) |
| 78 | * |
| 79 | * Allocations >= ZoneLimit go directly to kmem. |
| 80 | * |
| 81 | * Alignment properties: |
| 82 | * - All power-of-2 sized allocations are power-of-2 aligned. |
| 83 | * - Allocations with M_POWEROF2 are power-of-2 aligned on the nearest |
| 84 | * power-of-2 round up of 'size'. |
| 85 | * - Non-power-of-2 sized allocations are zone chunk size aligned (see the |
| 86 | * above table 'Chunking' column). |
| 87 | * |
| 88 | * API REQUIREMENTS AND SIDE EFFECTS |
| 89 | * |
| 90 | * To operate as a drop-in replacement to the FreeBSD-4.x malloc() we |
| 91 | * have remained compatible with the following API requirements: |
| 92 | * |
| 93 | * + malloc(0) is allowed and returns non-NULL (ahc driver) |
| 94 | * + ability to allocate arbitrarily large chunks of memory |
| 95 | */ |
| 96 | |
| 97 | #include "opt_vm.h" |
| 98 | |
| 99 | #include <sys/param.h> |
| 100 | #include <sys/systm.h> |
| 101 | #include <sys/kernel.h> |
| 102 | #include <sys/slaballoc.h> |
| 103 | #include <sys/mbuf.h> |
| 104 | #include <sys/vmmeter.h> |
| 105 | #include <sys/lock.h> |
| 106 | #include <sys/thread.h> |
| 107 | #include <sys/globaldata.h> |
| 108 | #include <sys/sysctl.h> |
| 109 | #include <sys/ktr.h> |
| 110 | |
| 111 | #include <vm/vm.h> |
| 112 | #include <vm/vm_param.h> |
| 113 | #include <vm/vm_kern.h> |
| 114 | #include <vm/vm_extern.h> |
| 115 | #include <vm/vm_object.h> |
| 116 | #include <vm/pmap.h> |
| 117 | #include <vm/vm_map.h> |
| 118 | #include <vm/vm_page.h> |
| 119 | #include <vm/vm_pageout.h> |
| 120 | |
| 121 | #include <machine/cpu.h> |
| 122 | |
| 123 | #include <sys/thread2.h> |
| 124 | |
| 125 | #define btokup(z) (&pmap_kvtom((vm_offset_t)(z))->ku_pagecnt) |
| 126 | |
| 127 | #define MEMORY_STRING "ptr=%p type=%p size=%lu flags=%04x" |
| 128 | #define MEMORY_ARGS void *ptr, void *type, unsigned long size, int flags |
| 129 | |
| 130 | #if !defined(KTR_MEMORY) |
| 131 | #define KTR_MEMORY KTR_ALL |
| 132 | #endif |
| 133 | KTR_INFO_MASTER(memory); |
| 134 | KTR_INFO(KTR_MEMORY, memory, malloc_beg, 0, "malloc begin"); |
| 135 | KTR_INFO(KTR_MEMORY, memory, malloc_end, 1, MEMORY_STRING, MEMORY_ARGS); |
| 136 | KTR_INFO(KTR_MEMORY, memory, free_zero, 2, MEMORY_STRING, MEMORY_ARGS); |
| 137 | KTR_INFO(KTR_MEMORY, memory, free_ovsz, 3, MEMORY_STRING, MEMORY_ARGS); |
| 138 | KTR_INFO(KTR_MEMORY, memory, free_ovsz_delayed, 4, MEMORY_STRING, MEMORY_ARGS); |
| 139 | KTR_INFO(KTR_MEMORY, memory, free_chunk, 5, MEMORY_STRING, MEMORY_ARGS); |
| 140 | #ifdef SMP |
| 141 | KTR_INFO(KTR_MEMORY, memory, free_request, 6, MEMORY_STRING, MEMORY_ARGS); |
| 142 | KTR_INFO(KTR_MEMORY, memory, free_rem_beg, 7, MEMORY_STRING, MEMORY_ARGS); |
| 143 | KTR_INFO(KTR_MEMORY, memory, free_rem_end, 8, MEMORY_STRING, MEMORY_ARGS); |
| 144 | #endif |
| 145 | KTR_INFO(KTR_MEMORY, memory, free_beg, 9, "free begin"); |
| 146 | KTR_INFO(KTR_MEMORY, memory, free_end, 10, "free end"); |
| 147 | |
| 148 | #define logmemory(name, ptr, type, size, flags) \ |
| 149 | KTR_LOG(memory_ ## name, ptr, type, size, flags) |
| 150 | #define logmemory_quick(name) \ |
| 151 | KTR_LOG(memory_ ## name) |
| 152 | |
| 153 | /* |
| 154 | * Fixed globals (not per-cpu) |
| 155 | */ |
| 156 | static int ZoneSize; |
| 157 | static int ZoneLimit; |
| 158 | static int ZonePageCount; |
| 159 | static uintptr_t ZoneMask; |
| 160 | static int ZoneBigAlloc; /* in KB */ |
| 161 | static int ZoneGenAlloc; /* in KB */ |
| 162 | struct malloc_type *kmemstatistics; /* exported to vmstat */ |
| 163 | static int32_t weirdary[16]; |
| 164 | |
| 165 | static void *kmem_slab_alloc(vm_size_t bytes, vm_offset_t align, int flags); |
| 166 | static void kmem_slab_free(void *ptr, vm_size_t bytes); |
| 167 | |
| 168 | #if defined(INVARIANTS) |
| 169 | static void chunk_mark_allocated(SLZone *z, void *chunk); |
| 170 | static void chunk_mark_free(SLZone *z, void *chunk); |
| 171 | #else |
| 172 | #define chunk_mark_allocated(z, chunk) |
| 173 | #define chunk_mark_free(z, chunk) |
| 174 | #endif |
| 175 | |
| 176 | /* |
| 177 | * Misc constants. Note that allocations that are exact multiples of |
| 178 | * PAGE_SIZE, or exceed the zone limit, fall through to the kmem module. |
| 179 | */ |
| 180 | #define ZONE_RELS_THRESH 32 /* threshold number of zones */ |
| 181 | |
| 182 | /* |
| 183 | * The WEIRD_ADDR is used as known text to copy into free objects to |
| 184 | * try to create deterministic failure cases if the data is accessed after |
| 185 | * free. |
| 186 | */ |
| 187 | #define WEIRD_ADDR 0xdeadc0de |
| 188 | #define MAX_COPY sizeof(weirdary) |
| 189 | #define ZERO_LENGTH_PTR ((void *)-8) |
| 190 | |
| 191 | /* |
| 192 | * Misc global malloc buckets |
| 193 | */ |
| 194 | |
| 195 | MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches"); |
| 196 | MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); |
| 197 | MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers"); |
| 198 | |
| 199 | MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options"); |
| 200 | MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery"); |
| 201 | |
| 202 | /* |
| 203 | * Initialize the slab memory allocator. We have to choose a zone size based |
| 204 | * on available physical memory. We choose a zone side which is approximately |
| 205 | * 1/1024th of our memory, so if we have 128MB of ram we have a zone size of |
| 206 | * 128K. The zone size is limited to the bounds set in slaballoc.h |
| 207 | * (typically 32K min, 128K max). |
| 208 | */ |
| 209 | static void kmeminit(void *dummy); |
| 210 | |
| 211 | char *ZeroPage; |
| 212 | |
| 213 | SYSINIT(kmem, SI_BOOT1_ALLOCATOR, SI_ORDER_FIRST, kmeminit, NULL) |
| 214 | |
| 215 | #ifdef INVARIANTS |
| 216 | /* |
| 217 | * If enabled any memory allocated without M_ZERO is initialized to -1. |
| 218 | */ |
| 219 | static int use_malloc_pattern; |
| 220 | SYSCTL_INT(_debug, OID_AUTO, use_malloc_pattern, CTLFLAG_RW, |
| 221 | &use_malloc_pattern, 0, |
| 222 | "Initialize memory to -1 if M_ZERO not specified"); |
| 223 | #endif |
| 224 | |
| 225 | static int ZoneRelsThresh = ZONE_RELS_THRESH; |
| 226 | SYSCTL_INT(_kern, OID_AUTO, zone_big_alloc, CTLFLAG_RD, &ZoneBigAlloc, 0, ""); |
| 227 | SYSCTL_INT(_kern, OID_AUTO, zone_gen_alloc, CTLFLAG_RD, &ZoneGenAlloc, 0, ""); |
| 228 | SYSCTL_INT(_kern, OID_AUTO, zone_cache, CTLFLAG_RW, &ZoneRelsThresh, 0, ""); |
| 229 | |
| 230 | /* |
| 231 | * Returns the kernel memory size limit for the purposes of initializing |
| 232 | * various subsystem caches. The smaller of available memory and the KVM |
| 233 | * memory space is returned. |
| 234 | * |
| 235 | * The size in megabytes is returned. |
| 236 | */ |
| 237 | size_t |
| 238 | kmem_lim_size(void) |
| 239 | { |
| 240 | size_t limsize; |
| 241 | |
| 242 | limsize = (size_t)vmstats.v_page_count * PAGE_SIZE; |
| 243 | if (limsize > KvaSize) |
| 244 | limsize = KvaSize; |
| 245 | return (limsize / (1024 * 1024)); |
| 246 | } |
| 247 | |
| 248 | static void |
| 249 | kmeminit(void *dummy) |
| 250 | { |
| 251 | size_t limsize; |
| 252 | int usesize; |
| 253 | int i; |
| 254 | |
| 255 | limsize = kmem_lim_size(); |
| 256 | usesize = (int)(limsize * 1024); /* convert to KB */ |
| 257 | |
| 258 | /* |
| 259 | * If the machine has a large KVM space and more than 8G of ram, |
| 260 | * double the zone release threshold to reduce SMP invalidations. |
| 261 | * If more than 16G of ram, do it again. |
| 262 | * |
| 263 | * The BIOS eats a little ram so add some slop. We want 8G worth of |
| 264 | * memory sticks to trigger the first adjustment. |
| 265 | */ |
| 266 | if (ZoneRelsThresh == ZONE_RELS_THRESH) { |
| 267 | if (limsize >= 7 * 1024) |
| 268 | ZoneRelsThresh *= 2; |
| 269 | if (limsize >= 15 * 1024) |
| 270 | ZoneRelsThresh *= 2; |
| 271 | } |
| 272 | |
| 273 | /* |
| 274 | * Calculate the zone size. This typically calculates to |
| 275 | * ZALLOC_MAX_ZONE_SIZE |
| 276 | */ |
| 277 | ZoneSize = ZALLOC_MIN_ZONE_SIZE; |
| 278 | while (ZoneSize < ZALLOC_MAX_ZONE_SIZE && (ZoneSize << 1) < usesize) |
| 279 | ZoneSize <<= 1; |
| 280 | ZoneLimit = ZoneSize / 4; |
| 281 | if (ZoneLimit > ZALLOC_ZONE_LIMIT) |
| 282 | ZoneLimit = ZALLOC_ZONE_LIMIT; |
| 283 | ZoneMask = ~(uintptr_t)(ZoneSize - 1); |
| 284 | ZonePageCount = ZoneSize / PAGE_SIZE; |
| 285 | |
| 286 | for (i = 0; i < NELEM(weirdary); ++i) |
| 287 | weirdary[i] = WEIRD_ADDR; |
| 288 | |
| 289 | ZeroPage = kmem_slab_alloc(PAGE_SIZE, PAGE_SIZE, M_WAITOK|M_ZERO); |
| 290 | |
| 291 | if (bootverbose) |
| 292 | kprintf("Slab ZoneSize set to %dKB\n", ZoneSize / 1024); |
| 293 | } |
| 294 | |
| 295 | /* |
| 296 | * Initialize a malloc type tracking structure. |
| 297 | */ |
| 298 | void |
| 299 | malloc_init(void *data) |
| 300 | { |
| 301 | struct malloc_type *type = data; |
| 302 | size_t limsize; |
| 303 | |
| 304 | if (type->ks_magic != M_MAGIC) |
| 305 | panic("malloc type lacks magic"); |
| 306 | |
| 307 | if (type->ks_limit != 0) |
| 308 | return; |
| 309 | |
| 310 | if (vmstats.v_page_count == 0) |
| 311 | panic("malloc_init not allowed before vm init"); |
| 312 | |
| 313 | limsize = kmem_lim_size() * (1024 * 1024); |
| 314 | type->ks_limit = limsize / 10; |
| 315 | |
| 316 | type->ks_next = kmemstatistics; |
| 317 | kmemstatistics = type; |
| 318 | } |
| 319 | |
| 320 | void |
| 321 | malloc_uninit(void *data) |
| 322 | { |
| 323 | struct malloc_type *type = data; |
| 324 | struct malloc_type *t; |
| 325 | #ifdef INVARIANTS |
| 326 | int i; |
| 327 | long ttl; |
| 328 | #endif |
| 329 | |
| 330 | if (type->ks_magic != M_MAGIC) |
| 331 | panic("malloc type lacks magic"); |
| 332 | |
| 333 | if (vmstats.v_page_count == 0) |
| 334 | panic("malloc_uninit not allowed before vm init"); |
| 335 | |
| 336 | if (type->ks_limit == 0) |
| 337 | panic("malloc_uninit on uninitialized type"); |
| 338 | |
| 339 | #ifdef SMP |
| 340 | /* Make sure that all pending kfree()s are finished. */ |
| 341 | lwkt_synchronize_ipiqs("muninit"); |
| 342 | #endif |
| 343 | |
| 344 | #ifdef INVARIANTS |
| 345 | /* |
| 346 | * memuse is only correct in aggregation. Due to memory being allocated |
| 347 | * on one cpu and freed on another individual array entries may be |
| 348 | * negative or positive (canceling each other out). |
| 349 | */ |
| 350 | for (i = ttl = 0; i < ncpus; ++i) |
| 351 | ttl += type->ks_memuse[i]; |
| 352 | if (ttl) { |
| 353 | kprintf("malloc_uninit: %ld bytes of '%s' still allocated on cpu %d\n", |
| 354 | ttl, type->ks_shortdesc, i); |
| 355 | } |
| 356 | #endif |
| 357 | if (type == kmemstatistics) { |
| 358 | kmemstatistics = type->ks_next; |
| 359 | } else { |
| 360 | for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) { |
| 361 | if (t->ks_next == type) { |
| 362 | t->ks_next = type->ks_next; |
| 363 | break; |
| 364 | } |
| 365 | } |
| 366 | } |
| 367 | type->ks_next = NULL; |
| 368 | type->ks_limit = 0; |
| 369 | } |
| 370 | |
| 371 | /* |
| 372 | * Increase the kmalloc pool limit for the specified pool. No changes |
| 373 | * are the made if the pool would shrink. |
| 374 | */ |
| 375 | void |
| 376 | kmalloc_raise_limit(struct malloc_type *type, size_t bytes) |
| 377 | { |
| 378 | if (type->ks_limit == 0) |
| 379 | malloc_init(type); |
| 380 | if (bytes == 0) |
| 381 | bytes = KvaSize; |
| 382 | if (type->ks_limit < bytes) |
| 383 | type->ks_limit = bytes; |
| 384 | } |
| 385 | |
| 386 | /* |
| 387 | * Dynamically create a malloc pool. This function is a NOP if *typep is |
| 388 | * already non-NULL. |
| 389 | */ |
| 390 | void |
| 391 | kmalloc_create(struct malloc_type **typep, const char *descr) |
| 392 | { |
| 393 | struct malloc_type *type; |
| 394 | |
| 395 | if (*typep == NULL) { |
| 396 | type = kmalloc(sizeof(*type), M_TEMP, M_WAITOK | M_ZERO); |
| 397 | type->ks_magic = M_MAGIC; |
| 398 | type->ks_shortdesc = descr; |
| 399 | malloc_init(type); |
| 400 | *typep = type; |
| 401 | } |
| 402 | } |
| 403 | |
| 404 | /* |
| 405 | * Destroy a dynamically created malloc pool. This function is a NOP if |
| 406 | * the pool has already been destroyed. |
| 407 | */ |
| 408 | void |
| 409 | kmalloc_destroy(struct malloc_type **typep) |
| 410 | { |
| 411 | if (*typep != NULL) { |
| 412 | malloc_uninit(*typep); |
| 413 | kfree(*typep, M_TEMP); |
| 414 | *typep = NULL; |
| 415 | } |
| 416 | } |
| 417 | |
| 418 | /* |
| 419 | * Calculate the zone index for the allocation request size and set the |
| 420 | * allocation request size to that particular zone's chunk size. |
| 421 | */ |
| 422 | static __inline int |
| 423 | zoneindex(unsigned long *bytes, unsigned long *align) |
| 424 | { |
| 425 | unsigned int n = (unsigned int)*bytes; /* unsigned for shift opt */ |
| 426 | if (n < 128) { |
| 427 | *bytes = n = (n + 7) & ~7; |
| 428 | *align = 8; |
| 429 | return(n / 8 - 1); /* 8 byte chunks, 16 zones */ |
| 430 | } |
| 431 | if (n < 256) { |
| 432 | *bytes = n = (n + 15) & ~15; |
| 433 | *align = 16; |
| 434 | return(n / 16 + 7); |
| 435 | } |
| 436 | if (n < 8192) { |
| 437 | if (n < 512) { |
| 438 | *bytes = n = (n + 31) & ~31; |
| 439 | *align = 32; |
| 440 | return(n / 32 + 15); |
| 441 | } |
| 442 | if (n < 1024) { |
| 443 | *bytes = n = (n + 63) & ~63; |
| 444 | *align = 64; |
| 445 | return(n / 64 + 23); |
| 446 | } |
| 447 | if (n < 2048) { |
| 448 | *bytes = n = (n + 127) & ~127; |
| 449 | *align = 128; |
| 450 | return(n / 128 + 31); |
| 451 | } |
| 452 | if (n < 4096) { |
| 453 | *bytes = n = (n + 255) & ~255; |
| 454 | *align = 256; |
| 455 | return(n / 256 + 39); |
| 456 | } |
| 457 | *bytes = n = (n + 511) & ~511; |
| 458 | *align = 512; |
| 459 | return(n / 512 + 47); |
| 460 | } |
| 461 | #if ZALLOC_ZONE_LIMIT > 8192 |
| 462 | if (n < 16384) { |
| 463 | *bytes = n = (n + 1023) & ~1023; |
| 464 | *align = 1024; |
| 465 | return(n / 1024 + 55); |
| 466 | } |
| 467 | #endif |
| 468 | #if ZALLOC_ZONE_LIMIT > 16384 |
| 469 | if (n < 32768) { |
| 470 | *bytes = n = (n + 2047) & ~2047; |
| 471 | *align = 2048; |
| 472 | return(n / 2048 + 63); |
| 473 | } |
| 474 | #endif |
| 475 | panic("Unexpected byte count %d", n); |
| 476 | return(0); |
| 477 | } |
| 478 | |
| 479 | #ifdef SLAB_DEBUG |
| 480 | /* |
| 481 | * Used to debug memory corruption issues. Record up to (typically 32) |
| 482 | * allocation sources for this zone (for a particular chunk size). |
| 483 | */ |
| 484 | |
| 485 | static void |
| 486 | slab_record_source(SLZone *z, const char *file, int line) |
| 487 | { |
| 488 | int i; |
| 489 | int b = line & (SLAB_DEBUG_ENTRIES - 1); |
| 490 | |
| 491 | i = b; |
| 492 | do { |
| 493 | if (z->z_Sources[i].file == file && z->z_Sources[i].line == line) |
| 494 | return; |
| 495 | if (z->z_Sources[i].file == NULL) |
| 496 | break; |
| 497 | i = (i + 1) & (SLAB_DEBUG_ENTRIES - 1); |
| 498 | } while (i != b); |
| 499 | z->z_Sources[i].file = file; |
| 500 | z->z_Sources[i].line = line; |
| 501 | } |
| 502 | |
| 503 | #endif |
| 504 | |
| 505 | static __inline unsigned long |
| 506 | powerof2_size(unsigned long size) |
| 507 | { |
| 508 | int i; |
| 509 | |
| 510 | if (size == 0 || powerof2(size)) |
| 511 | return size; |
| 512 | |
| 513 | i = flsl(size); |
| 514 | return (1UL << i); |
| 515 | } |
| 516 | |
| 517 | /* |
| 518 | * kmalloc() (SLAB ALLOCATOR) |
| 519 | * |
| 520 | * Allocate memory via the slab allocator. If the request is too large, |
| 521 | * or if it page-aligned beyond a certain size, we fall back to the |
| 522 | * KMEM subsystem. A SLAB tracking descriptor must be specified, use |
| 523 | * &SlabMisc if you don't care. |
| 524 | * |
| 525 | * M_RNOWAIT - don't block. |
| 526 | * M_NULLOK - return NULL instead of blocking. |
| 527 | * M_ZERO - zero the returned memory. |
| 528 | * M_USE_RESERVE - allow greater drawdown of the free list |
| 529 | * M_USE_INTERRUPT_RESERVE - allow the freelist to be exhausted |
| 530 | * M_POWEROF2 - roundup size to the nearest power of 2 |
| 531 | * |
| 532 | * MPSAFE |
| 533 | */ |
| 534 | |
| 535 | #ifdef SLAB_DEBUG |
| 536 | void * |
| 537 | kmalloc_debug(unsigned long size, struct malloc_type *type, int flags, |
| 538 | const char *file, int line) |
| 539 | #else |
| 540 | void * |
| 541 | kmalloc(unsigned long size, struct malloc_type *type, int flags) |
| 542 | #endif |
| 543 | { |
| 544 | SLZone *z; |
| 545 | SLChunk *chunk; |
| 546 | #ifdef SMP |
| 547 | SLChunk *bchunk; |
| 548 | #endif |
| 549 | SLGlobalData *slgd; |
| 550 | struct globaldata *gd; |
| 551 | unsigned long align; |
| 552 | int zi; |
| 553 | #ifdef INVARIANTS |
| 554 | int i; |
| 555 | #endif |
| 556 | |
| 557 | logmemory_quick(malloc_beg); |
| 558 | gd = mycpu; |
| 559 | slgd = &gd->gd_slab; |
| 560 | |
| 561 | /* |
| 562 | * XXX silly to have this in the critical path. |
| 563 | */ |
| 564 | if (type->ks_limit == 0) { |
| 565 | crit_enter(); |
| 566 | if (type->ks_limit == 0) |
| 567 | malloc_init(type); |
| 568 | crit_exit(); |
| 569 | } |
| 570 | ++type->ks_calls; |
| 571 | |
| 572 | if (flags & M_POWEROF2) |
| 573 | size = powerof2_size(size); |
| 574 | |
| 575 | /* |
| 576 | * Handle the case where the limit is reached. Panic if we can't return |
| 577 | * NULL. The original malloc code looped, but this tended to |
| 578 | * simply deadlock the computer. |
| 579 | * |
| 580 | * ks_loosememuse is an up-only limit that is NOT MP-synchronized, used |
| 581 | * to determine if a more complete limit check should be done. The |
| 582 | * actual memory use is tracked via ks_memuse[cpu]. |
| 583 | */ |
| 584 | while (type->ks_loosememuse >= type->ks_limit) { |
| 585 | int i; |
| 586 | long ttl; |
| 587 | |
| 588 | for (i = ttl = 0; i < ncpus; ++i) |
| 589 | ttl += type->ks_memuse[i]; |
| 590 | type->ks_loosememuse = ttl; /* not MP synchronized */ |
| 591 | if ((ssize_t)ttl < 0) /* deal with occassional race */ |
| 592 | ttl = 0; |
| 593 | if (ttl >= type->ks_limit) { |
| 594 | if (flags & M_NULLOK) { |
| 595 | logmemory(malloc_end, NULL, type, size, flags); |
| 596 | return(NULL); |
| 597 | } |
| 598 | panic("%s: malloc limit exceeded", type->ks_shortdesc); |
| 599 | } |
| 600 | } |
| 601 | |
| 602 | /* |
| 603 | * Handle the degenerate size == 0 case. Yes, this does happen. |
| 604 | * Return a special pointer. This is to maintain compatibility with |
| 605 | * the original malloc implementation. Certain devices, such as the |
| 606 | * adaptec driver, not only allocate 0 bytes, they check for NULL and |
| 607 | * also realloc() later on. Joy. |
| 608 | */ |
| 609 | if (size == 0) { |
| 610 | logmemory(malloc_end, ZERO_LENGTH_PTR, type, size, flags); |
| 611 | return(ZERO_LENGTH_PTR); |
| 612 | } |
| 613 | |
| 614 | /* |
| 615 | * Handle hysteresis from prior frees here in malloc(). We cannot |
| 616 | * safely manipulate the kernel_map in free() due to free() possibly |
| 617 | * being called via an IPI message or from sensitive interrupt code. |
| 618 | * |
| 619 | * NOTE: ku_pagecnt must be cleared before we free the slab or we |
| 620 | * might race another cpu allocating the kva and setting |
| 621 | * ku_pagecnt. |
| 622 | */ |
| 623 | while (slgd->NFreeZones > ZoneRelsThresh && (flags & M_RNOWAIT) == 0) { |
| 624 | crit_enter(); |
| 625 | if (slgd->NFreeZones > ZoneRelsThresh) { /* crit sect race */ |
| 626 | int *kup; |
| 627 | |
| 628 | z = slgd->FreeZones; |
| 629 | slgd->FreeZones = z->z_Next; |
| 630 | --slgd->NFreeZones; |
| 631 | kup = btokup(z); |
| 632 | *kup = 0; |
| 633 | kmem_slab_free(z, ZoneSize); /* may block */ |
| 634 | atomic_add_int(&ZoneGenAlloc, -ZoneSize / 1024); |
| 635 | } |
| 636 | crit_exit(); |
| 637 | } |
| 638 | |
| 639 | /* |
| 640 | * XXX handle oversized frees that were queued from kfree(). |
| 641 | */ |
| 642 | while (slgd->FreeOvZones && (flags & M_RNOWAIT) == 0) { |
| 643 | crit_enter(); |
| 644 | if ((z = slgd->FreeOvZones) != NULL) { |
| 645 | vm_size_t tsize; |
| 646 | |
| 647 | KKASSERT(z->z_Magic == ZALLOC_OVSZ_MAGIC); |
| 648 | slgd->FreeOvZones = z->z_Next; |
| 649 | tsize = z->z_ChunkSize; |
| 650 | kmem_slab_free(z, tsize); /* may block */ |
| 651 | atomic_add_int(&ZoneBigAlloc, -(int)tsize / 1024); |
| 652 | } |
| 653 | crit_exit(); |
| 654 | } |
| 655 | |
| 656 | /* |
| 657 | * Handle large allocations directly. There should not be very many of |
| 658 | * these so performance is not a big issue. |
| 659 | * |
| 660 | * The backend allocator is pretty nasty on a SMP system. Use the |
| 661 | * slab allocator for one and two page-sized chunks even though we lose |
| 662 | * some efficiency. XXX maybe fix mmio and the elf loader instead. |
| 663 | */ |
| 664 | if (size >= ZoneLimit || ((size & PAGE_MASK) == 0 && size > PAGE_SIZE*2)) { |
| 665 | int *kup; |
| 666 | |
| 667 | size = round_page(size); |
| 668 | chunk = kmem_slab_alloc(size, PAGE_SIZE, flags); |
| 669 | if (chunk == NULL) { |
| 670 | logmemory(malloc_end, NULL, type, size, flags); |
| 671 | return(NULL); |
| 672 | } |
| 673 | atomic_add_int(&ZoneBigAlloc, (int)size / 1024); |
| 674 | flags &= ~M_ZERO; /* result already zero'd if M_ZERO was set */ |
| 675 | flags |= M_PASSIVE_ZERO; |
| 676 | kup = btokup(chunk); |
| 677 | *kup = size / PAGE_SIZE; |
| 678 | crit_enter(); |
| 679 | goto done; |
| 680 | } |
| 681 | |
| 682 | /* |
| 683 | * Attempt to allocate out of an existing zone. First try the free list, |
| 684 | * then allocate out of unallocated space. If we find a good zone move |
| 685 | * it to the head of the list so later allocations find it quickly |
| 686 | * (we might have thousands of zones in the list). |
| 687 | * |
| 688 | * Note: zoneindex() will panic of size is too large. |
| 689 | */ |
| 690 | zi = zoneindex(&size, &align); |
| 691 | KKASSERT(zi < NZONES); |
| 692 | crit_enter(); |
| 693 | |
| 694 | if ((z = slgd->ZoneAry[zi]) != NULL) { |
| 695 | /* |
| 696 | * Locate a chunk - we have to have at least one. If this is the |
| 697 | * last chunk go ahead and do the work to retrieve chunks freed |
| 698 | * from remote cpus, and if the zone is still empty move it off |
| 699 | * the ZoneAry. |
| 700 | */ |
| 701 | if (--z->z_NFree <= 0) { |
| 702 | KKASSERT(z->z_NFree == 0); |
| 703 | |
| 704 | #ifdef SMP |
| 705 | /* |
| 706 | * WARNING! This code competes with other cpus. It is ok |
| 707 | * for us to not drain RChunks here but we might as well, and |
| 708 | * it is ok if more accumulate after we're done. |
| 709 | * |
| 710 | * Set RSignal before pulling rchunks off, indicating that we |
| 711 | * will be moving ourselves off of the ZoneAry. Remote ends will |
| 712 | * read RSignal before putting rchunks on thus interlocking |
| 713 | * their IPI signaling. |
| 714 | */ |
| 715 | if (z->z_RChunks == NULL) |
| 716 | atomic_swap_int(&z->z_RSignal, 1); |
| 717 | |
| 718 | while ((bchunk = z->z_RChunks) != NULL) { |
| 719 | cpu_ccfence(); |
| 720 | if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, NULL)) { |
| 721 | *z->z_LChunksp = bchunk; |
| 722 | while (bchunk) { |
| 723 | chunk_mark_free(z, bchunk); |
| 724 | z->z_LChunksp = &bchunk->c_Next; |
| 725 | bchunk = bchunk->c_Next; |
| 726 | ++z->z_NFree; |
| 727 | } |
| 728 | break; |
| 729 | } |
| 730 | } |
| 731 | #endif |
| 732 | /* |
| 733 | * Remove from the zone list if no free chunks remain. |
| 734 | * Clear RSignal |
| 735 | */ |
| 736 | if (z->z_NFree == 0) { |
| 737 | slgd->ZoneAry[zi] = z->z_Next; |
| 738 | z->z_Next = NULL; |
| 739 | } else { |
| 740 | z->z_RSignal = 0; |
| 741 | } |
| 742 | } |
| 743 | |
| 744 | /* |
| 745 | * Fast path, we have chunks available in z_LChunks. |
| 746 | */ |
| 747 | chunk = z->z_LChunks; |
| 748 | if (chunk) { |
| 749 | chunk_mark_allocated(z, chunk); |
| 750 | z->z_LChunks = chunk->c_Next; |
| 751 | if (z->z_LChunks == NULL) |
| 752 | z->z_LChunksp = &z->z_LChunks; |
| 753 | #ifdef SLAB_DEBUG |
| 754 | slab_record_source(z, file, line); |
| 755 | #endif |
| 756 | goto done; |
| 757 | } |
| 758 | |
| 759 | /* |
| 760 | * No chunks are available in LChunks, the free chunk MUST be |
| 761 | * in the never-before-used memory area, controlled by UIndex. |
| 762 | * |
| 763 | * The consequences are very serious if our zone got corrupted so |
| 764 | * we use an explicit panic rather than a KASSERT. |
| 765 | */ |
| 766 | if (z->z_UIndex + 1 != z->z_NMax) |
| 767 | ++z->z_UIndex; |
| 768 | else |
| 769 | z->z_UIndex = 0; |
| 770 | |
| 771 | if (z->z_UIndex == z->z_UEndIndex) |
| 772 | panic("slaballoc: corrupted zone"); |
| 773 | |
| 774 | chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size); |
| 775 | if ((z->z_Flags & SLZF_UNOTZEROD) == 0) { |
| 776 | flags &= ~M_ZERO; |
| 777 | flags |= M_PASSIVE_ZERO; |
| 778 | } |
| 779 | chunk_mark_allocated(z, chunk); |
| 780 | #ifdef SLAB_DEBUG |
| 781 | slab_record_source(z, file, line); |
| 782 | #endif |
| 783 | goto done; |
| 784 | } |
| 785 | |
| 786 | /* |
| 787 | * If all zones are exhausted we need to allocate a new zone for this |
| 788 | * index. Use M_ZERO to take advantage of pre-zerod pages. Also see |
| 789 | * UAlloc use above in regards to M_ZERO. Note that when we are reusing |
| 790 | * a zone from the FreeZones list UAlloc'd data will not be zero'd, and |
| 791 | * we do not pre-zero it because we do not want to mess up the L1 cache. |
| 792 | * |
| 793 | * At least one subsystem, the tty code (see CROUND) expects power-of-2 |
| 794 | * allocations to be power-of-2 aligned. We maintain compatibility by |
| 795 | * adjusting the base offset below. |
| 796 | */ |
| 797 | { |
| 798 | int off; |
| 799 | int *kup; |
| 800 | |
| 801 | if ((z = slgd->FreeZones) != NULL) { |
| 802 | slgd->FreeZones = z->z_Next; |
| 803 | --slgd->NFreeZones; |
| 804 | bzero(z, sizeof(SLZone)); |
| 805 | z->z_Flags |= SLZF_UNOTZEROD; |
| 806 | } else { |
| 807 | z = kmem_slab_alloc(ZoneSize, ZoneSize, flags|M_ZERO); |
| 808 | if (z == NULL) |
| 809 | goto fail; |
| 810 | atomic_add_int(&ZoneGenAlloc, ZoneSize / 1024); |
| 811 | } |
| 812 | |
| 813 | /* |
| 814 | * How big is the base structure? |
| 815 | */ |
| 816 | #if defined(INVARIANTS) |
| 817 | /* |
| 818 | * Make room for z_Bitmap. An exact calculation is somewhat more |
| 819 | * complicated so don't make an exact calculation. |
| 820 | */ |
| 821 | off = offsetof(SLZone, z_Bitmap[(ZoneSize / size + 31) / 32]); |
| 822 | bzero(z->z_Bitmap, (ZoneSize / size + 31) / 8); |
| 823 | #else |
| 824 | off = sizeof(SLZone); |
| 825 | #endif |
| 826 | |
| 827 | /* |
| 828 | * Guarentee power-of-2 alignment for power-of-2-sized chunks. |
| 829 | * Otherwise just 8-byte align the data. |
| 830 | */ |
| 831 | if ((size | (size - 1)) + 1 == (size << 1)) |
| 832 | off = (off + size - 1) & ~(size - 1); |
| 833 | else |
| 834 | off = (off + align - 1) & ~(align - 1); |
| 835 | z->z_Magic = ZALLOC_SLAB_MAGIC; |
| 836 | z->z_ZoneIndex = zi; |
| 837 | z->z_NMax = (ZoneSize - off) / size; |
| 838 | z->z_NFree = z->z_NMax - 1; |
| 839 | z->z_BasePtr = (char *)z + off; |
| 840 | z->z_UIndex = z->z_UEndIndex = slgd->JunkIndex % z->z_NMax; |
| 841 | z->z_ChunkSize = size; |
| 842 | z->z_CpuGd = gd; |
| 843 | z->z_Cpu = gd->gd_cpuid; |
| 844 | z->z_LChunksp = &z->z_LChunks; |
| 845 | #ifdef SLAB_DEBUG |
| 846 | bcopy(z->z_Sources, z->z_AltSources, sizeof(z->z_Sources)); |
| 847 | bzero(z->z_Sources, sizeof(z->z_Sources)); |
| 848 | #endif |
| 849 | chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size); |
| 850 | z->z_Next = slgd->ZoneAry[zi]; |
| 851 | slgd->ZoneAry[zi] = z; |
| 852 | if ((z->z_Flags & SLZF_UNOTZEROD) == 0) { |
| 853 | flags &= ~M_ZERO; /* already zero'd */ |
| 854 | flags |= M_PASSIVE_ZERO; |
| 855 | } |
| 856 | kup = btokup(z); |
| 857 | *kup = -(z->z_Cpu + 1); /* -1 to -(N+1) */ |
| 858 | chunk_mark_allocated(z, chunk); |
| 859 | #ifdef SLAB_DEBUG |
| 860 | slab_record_source(z, file, line); |
| 861 | #endif |
| 862 | |
| 863 | /* |
| 864 | * Slide the base index for initial allocations out of the next |
| 865 | * zone we create so we do not over-weight the lower part of the |
| 866 | * cpu memory caches. |
| 867 | */ |
| 868 | slgd->JunkIndex = (slgd->JunkIndex + ZALLOC_SLAB_SLIDE) |
| 869 | & (ZALLOC_MAX_ZONE_SIZE - 1); |
| 870 | } |
| 871 | |
| 872 | done: |
| 873 | ++type->ks_inuse[gd->gd_cpuid]; |
| 874 | type->ks_memuse[gd->gd_cpuid] += size; |
| 875 | type->ks_loosememuse += size; /* not MP synchronized */ |
| 876 | crit_exit(); |
| 877 | |
| 878 | if (flags & M_ZERO) |
| 879 | bzero(chunk, size); |
| 880 | #ifdef INVARIANTS |
| 881 | else if ((flags & (M_ZERO|M_PASSIVE_ZERO)) == 0) { |
| 882 | if (use_malloc_pattern) { |
| 883 | for (i = 0; i < size; i += sizeof(int)) { |
| 884 | *(int *)((char *)chunk + i) = -1; |
| 885 | } |
| 886 | } |
| 887 | chunk->c_Next = (void *)-1; /* avoid accidental double-free check */ |
| 888 | } |
| 889 | #endif |
| 890 | logmemory(malloc_end, chunk, type, size, flags); |
| 891 | return(chunk); |
| 892 | fail: |
| 893 | crit_exit(); |
| 894 | logmemory(malloc_end, NULL, type, size, flags); |
| 895 | return(NULL); |
| 896 | } |
| 897 | |
| 898 | /* |
| 899 | * kernel realloc. (SLAB ALLOCATOR) (MP SAFE) |
| 900 | * |
| 901 | * Generally speaking this routine is not called very often and we do |
| 902 | * not attempt to optimize it beyond reusing the same pointer if the |
| 903 | * new size fits within the chunking of the old pointer's zone. |
| 904 | */ |
| 905 | #ifdef SLAB_DEBUG |
| 906 | void * |
| 907 | krealloc_debug(void *ptr, unsigned long size, |
| 908 | struct malloc_type *type, int flags, |
| 909 | const char *file, int line) |
| 910 | #else |
| 911 | void * |
| 912 | krealloc(void *ptr, unsigned long size, struct malloc_type *type, int flags) |
| 913 | #endif |
| 914 | { |
| 915 | unsigned long osize; |
| 916 | unsigned long align; |
| 917 | SLZone *z; |
| 918 | void *nptr; |
| 919 | int *kup; |
| 920 | |
| 921 | KKASSERT((flags & M_ZERO) == 0); /* not supported */ |
| 922 | |
| 923 | if (ptr == NULL || ptr == ZERO_LENGTH_PTR) |
| 924 | return(kmalloc_debug(size, type, flags, file, line)); |
| 925 | if (size == 0) { |
| 926 | kfree(ptr, type); |
| 927 | return(NULL); |
| 928 | } |
| 929 | |
| 930 | /* |
| 931 | * Handle oversized allocations. XXX we really should require that a |
| 932 | * size be passed to free() instead of this nonsense. |
| 933 | */ |
| 934 | kup = btokup(ptr); |
| 935 | if (*kup > 0) { |
| 936 | osize = *kup << PAGE_SHIFT; |
| 937 | if (osize == round_page(size)) |
| 938 | return(ptr); |
| 939 | if ((nptr = kmalloc_debug(size, type, flags, file, line)) == NULL) |
| 940 | return(NULL); |
| 941 | bcopy(ptr, nptr, min(size, osize)); |
| 942 | kfree(ptr, type); |
| 943 | return(nptr); |
| 944 | } |
| 945 | |
| 946 | /* |
| 947 | * Get the original allocation's zone. If the new request winds up |
| 948 | * using the same chunk size we do not have to do anything. |
| 949 | */ |
| 950 | z = (SLZone *)((uintptr_t)ptr & ZoneMask); |
| 951 | kup = btokup(z); |
| 952 | KKASSERT(*kup < 0); |
| 953 | KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC); |
| 954 | |
| 955 | /* |
| 956 | * Allocate memory for the new request size. Note that zoneindex has |
| 957 | * already adjusted the request size to the appropriate chunk size, which |
| 958 | * should optimize our bcopy(). Then copy and return the new pointer. |
| 959 | * |
| 960 | * Resizing a non-power-of-2 allocation to a power-of-2 size does not |
| 961 | * necessary align the result. |
| 962 | * |
| 963 | * We can only zoneindex (to align size to the chunk size) if the new |
| 964 | * size is not too large. |
| 965 | */ |
| 966 | if (size < ZoneLimit) { |
| 967 | zoneindex(&size, &align); |
| 968 | if (z->z_ChunkSize == size) |
| 969 | return(ptr); |
| 970 | } |
| 971 | if ((nptr = kmalloc_debug(size, type, flags, file, line)) == NULL) |
| 972 | return(NULL); |
| 973 | bcopy(ptr, nptr, min(size, z->z_ChunkSize)); |
| 974 | kfree(ptr, type); |
| 975 | return(nptr); |
| 976 | } |
| 977 | |
| 978 | /* |
| 979 | * Return the kmalloc limit for this type, in bytes. |
| 980 | */ |
| 981 | long |
| 982 | kmalloc_limit(struct malloc_type *type) |
| 983 | { |
| 984 | if (type->ks_limit == 0) { |
| 985 | crit_enter(); |
| 986 | if (type->ks_limit == 0) |
| 987 | malloc_init(type); |
| 988 | crit_exit(); |
| 989 | } |
| 990 | return(type->ks_limit); |
| 991 | } |
| 992 | |
| 993 | /* |
| 994 | * Allocate a copy of the specified string. |
| 995 | * |
| 996 | * (MP SAFE) (MAY BLOCK) |
| 997 | */ |
| 998 | #ifdef SLAB_DEBUG |
| 999 | char * |
| 1000 | kstrdup_debug(const char *str, struct malloc_type *type, |
| 1001 | const char *file, int line) |
| 1002 | #else |
| 1003 | char * |
| 1004 | kstrdup(const char *str, struct malloc_type *type) |
| 1005 | #endif |
| 1006 | { |
| 1007 | int zlen; /* length inclusive of terminating NUL */ |
| 1008 | char *nstr; |
| 1009 | |
| 1010 | if (str == NULL) |
| 1011 | return(NULL); |
| 1012 | zlen = strlen(str) + 1; |
| 1013 | nstr = kmalloc_debug(zlen, type, M_WAITOK, file, line); |
| 1014 | bcopy(str, nstr, zlen); |
| 1015 | return(nstr); |
| 1016 | } |
| 1017 | |
| 1018 | #ifdef SMP |
| 1019 | /* |
| 1020 | * Notify our cpu that a remote cpu has freed some chunks in a zone that |
| 1021 | * we own. RCount will be bumped so the memory should be good, but validate |
| 1022 | * that it really is. |
| 1023 | */ |
| 1024 | static |
| 1025 | void |
| 1026 | kfree_remote(void *ptr) |
| 1027 | { |
| 1028 | SLGlobalData *slgd; |
| 1029 | SLChunk *bchunk; |
| 1030 | SLZone *z; |
| 1031 | int nfree; |
| 1032 | int *kup; |
| 1033 | |
| 1034 | slgd = &mycpu->gd_slab; |
| 1035 | z = ptr; |
| 1036 | kup = btokup(z); |
| 1037 | KKASSERT(*kup == -((int)mycpuid + 1)); |
| 1038 | KKASSERT(z->z_RCount > 0); |
| 1039 | atomic_subtract_int(&z->z_RCount, 1); |
| 1040 | |
| 1041 | logmemory(free_rem_beg, z, NULL, 0L, 0); |
| 1042 | KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC); |
| 1043 | KKASSERT(z->z_Cpu == mycpu->gd_cpuid); |
| 1044 | nfree = z->z_NFree; |
| 1045 | |
| 1046 | /* |
| 1047 | * Indicate that we will no longer be off of the ZoneAry by |
| 1048 | * clearing RSignal. |
| 1049 | */ |
| 1050 | if (z->z_RChunks) |
| 1051 | z->z_RSignal = 0; |
| 1052 | |
| 1053 | /* |
| 1054 | * Atomically extract the bchunks list and then process it back |
| 1055 | * into the lchunks list. We want to append our bchunks to the |
| 1056 | * lchunks list and not prepend since we likely do not have |
| 1057 | * cache mastership of the related data (not that it helps since |
| 1058 | * we are using c_Next). |
| 1059 | */ |
| 1060 | while ((bchunk = z->z_RChunks) != NULL) { |
| 1061 | cpu_ccfence(); |
| 1062 | if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, NULL)) { |
| 1063 | *z->z_LChunksp = bchunk; |
| 1064 | while (bchunk) { |
| 1065 | chunk_mark_free(z, bchunk); |
| 1066 | z->z_LChunksp = &bchunk->c_Next; |
| 1067 | bchunk = bchunk->c_Next; |
| 1068 | ++z->z_NFree; |
| 1069 | } |
| 1070 | break; |
| 1071 | } |
| 1072 | } |
| 1073 | if (z->z_NFree && nfree == 0) { |
| 1074 | z->z_Next = slgd->ZoneAry[z->z_ZoneIndex]; |
| 1075 | slgd->ZoneAry[z->z_ZoneIndex] = z; |
| 1076 | } |
| 1077 | |
| 1078 | /* |
| 1079 | * If the zone becomes totally free, and there are other zones we |
| 1080 | * can allocate from, move this zone to the FreeZones list. Since |
| 1081 | * this code can be called from an IPI callback, do *NOT* try to mess |
| 1082 | * with kernel_map here. Hysteresis will be performed at malloc() time. |
| 1083 | * |
| 1084 | * Do not move the zone if there is an IPI inflight, otherwise MP |
| 1085 | * races can result in our free_remote code accessing a destroyed |
| 1086 | * zone. |
| 1087 | */ |
| 1088 | if (z->z_NFree == z->z_NMax && |
| 1089 | (z->z_Next || slgd->ZoneAry[z->z_ZoneIndex] != z) && |
| 1090 | z->z_RCount == 0 |
| 1091 | ) { |
| 1092 | SLZone **pz; |
| 1093 | int *kup; |
| 1094 | |
| 1095 | for (pz = &slgd->ZoneAry[z->z_ZoneIndex]; |
| 1096 | z != *pz; |
| 1097 | pz = &(*pz)->z_Next) { |
| 1098 | ; |
| 1099 | } |
| 1100 | *pz = z->z_Next; |
| 1101 | z->z_Magic = -1; |
| 1102 | z->z_Next = slgd->FreeZones; |
| 1103 | slgd->FreeZones = z; |
| 1104 | ++slgd->NFreeZones; |
| 1105 | kup = btokup(z); |
| 1106 | *kup = 0; |
| 1107 | } |
| 1108 | logmemory(free_rem_end, z, bchunk, 0L, 0); |
| 1109 | } |
| 1110 | |
| 1111 | #endif |
| 1112 | |
| 1113 | /* |
| 1114 | * free (SLAB ALLOCATOR) |
| 1115 | * |
| 1116 | * Free a memory block previously allocated by malloc. Note that we do not |
| 1117 | * attempt to update ks_loosememuse as MP races could prevent us from |
| 1118 | * checking memory limits in malloc. |
| 1119 | * |
| 1120 | * MPSAFE |
| 1121 | */ |
| 1122 | void |
| 1123 | kfree(void *ptr, struct malloc_type *type) |
| 1124 | { |
| 1125 | SLZone *z; |
| 1126 | SLChunk *chunk; |
| 1127 | SLGlobalData *slgd; |
| 1128 | struct globaldata *gd; |
| 1129 | int *kup; |
| 1130 | unsigned long size; |
| 1131 | #ifdef SMP |
| 1132 | SLChunk *bchunk; |
| 1133 | int rsignal; |
| 1134 | #endif |
| 1135 | |
| 1136 | logmemory_quick(free_beg); |
| 1137 | gd = mycpu; |
| 1138 | slgd = &gd->gd_slab; |
| 1139 | |
| 1140 | if (ptr == NULL) |
| 1141 | panic("trying to free NULL pointer"); |
| 1142 | |
| 1143 | /* |
| 1144 | * Handle special 0-byte allocations |
| 1145 | */ |
| 1146 | if (ptr == ZERO_LENGTH_PTR) { |
| 1147 | logmemory(free_zero, ptr, type, -1UL, 0); |
| 1148 | logmemory_quick(free_end); |
| 1149 | return; |
| 1150 | } |
| 1151 | |
| 1152 | /* |
| 1153 | * Panic on bad malloc type |
| 1154 | */ |
| 1155 | if (type->ks_magic != M_MAGIC) |
| 1156 | panic("free: malloc type lacks magic"); |
| 1157 | |
| 1158 | /* |
| 1159 | * Handle oversized allocations. XXX we really should require that a |
| 1160 | * size be passed to free() instead of this nonsense. |
| 1161 | * |
| 1162 | * This code is never called via an ipi. |
| 1163 | */ |
| 1164 | kup = btokup(ptr); |
| 1165 | if (*kup > 0) { |
| 1166 | size = *kup << PAGE_SHIFT; |
| 1167 | *kup = 0; |
| 1168 | #ifdef INVARIANTS |
| 1169 | KKASSERT(sizeof(weirdary) <= size); |
| 1170 | bcopy(weirdary, ptr, sizeof(weirdary)); |
| 1171 | #endif |
| 1172 | /* |
| 1173 | * NOTE: For oversized allocations we do not record the |
| 1174 | * originating cpu. It gets freed on the cpu calling |
| 1175 | * kfree(). The statistics are in aggregate. |
| 1176 | * |
| 1177 | * note: XXX we have still inherited the interrupts-can't-block |
| 1178 | * assumption. An interrupt thread does not bump |
| 1179 | * gd_intr_nesting_level so check TDF_INTTHREAD. This is |
| 1180 | * primarily until we can fix softupdate's assumptions about free(). |
| 1181 | */ |
| 1182 | crit_enter(); |
| 1183 | --type->ks_inuse[gd->gd_cpuid]; |
| 1184 | type->ks_memuse[gd->gd_cpuid] -= size; |
| 1185 | if (mycpu->gd_intr_nesting_level || |
| 1186 | (gd->gd_curthread->td_flags & TDF_INTTHREAD)) |
| 1187 | { |
| 1188 | logmemory(free_ovsz_delayed, ptr, type, size, 0); |
| 1189 | z = (SLZone *)ptr; |
| 1190 | z->z_Magic = ZALLOC_OVSZ_MAGIC; |
| 1191 | z->z_Next = slgd->FreeOvZones; |
| 1192 | z->z_ChunkSize = size; |
| 1193 | slgd->FreeOvZones = z; |
| 1194 | crit_exit(); |
| 1195 | } else { |
| 1196 | crit_exit(); |
| 1197 | logmemory(free_ovsz, ptr, type, size, 0); |
| 1198 | kmem_slab_free(ptr, size); /* may block */ |
| 1199 | atomic_add_int(&ZoneBigAlloc, -(int)size / 1024); |
| 1200 | } |
| 1201 | logmemory_quick(free_end); |
| 1202 | return; |
| 1203 | } |
| 1204 | |
| 1205 | /* |
| 1206 | * Zone case. Figure out the zone based on the fact that it is |
| 1207 | * ZoneSize aligned. |
| 1208 | */ |
| 1209 | z = (SLZone *)((uintptr_t)ptr & ZoneMask); |
| 1210 | kup = btokup(z); |
| 1211 | KKASSERT(*kup < 0); |
| 1212 | KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC); |
| 1213 | |
| 1214 | /* |
| 1215 | * If we do not own the zone then use atomic ops to free to the |
| 1216 | * remote cpu linked list and notify the target zone using a |
| 1217 | * passive message. |
| 1218 | * |
| 1219 | * The target zone cannot be deallocated while we own a chunk of it, |
| 1220 | * so the zone header's storage is stable until the very moment |
| 1221 | * we adjust z_RChunks. After that we cannot safely dereference (z). |
| 1222 | * |
| 1223 | * (no critical section needed) |
| 1224 | */ |
| 1225 | if (z->z_CpuGd != gd) { |
| 1226 | #ifdef SMP |
| 1227 | /* |
| 1228 | * Making these adjustments now allow us to avoid passing (type) |
| 1229 | * to the remote cpu. Note that ks_inuse/ks_memuse is being |
| 1230 | * adjusted on OUR cpu, not the zone cpu, but it should all still |
| 1231 | * sum up properly and cancel out. |
| 1232 | */ |
| 1233 | crit_enter(); |
| 1234 | --type->ks_inuse[gd->gd_cpuid]; |
| 1235 | type->ks_memuse[gd->gd_cpuid] -= z->z_ChunkSize; |
| 1236 | crit_exit(); |
| 1237 | |
| 1238 | /* |
| 1239 | * WARNING! This code competes with other cpus. Once we |
| 1240 | * successfully link the chunk to RChunks the remote |
| 1241 | * cpu can rip z's storage out from under us. |
| 1242 | * |
| 1243 | * Bumping RCount prevents z's storage from getting |
| 1244 | * ripped out. |
| 1245 | */ |
| 1246 | rsignal = z->z_RSignal; |
| 1247 | cpu_lfence(); |
| 1248 | if (rsignal) |
| 1249 | atomic_add_int(&z->z_RCount, 1); |
| 1250 | |
| 1251 | chunk = ptr; |
| 1252 | for (;;) { |
| 1253 | bchunk = z->z_RChunks; |
| 1254 | cpu_ccfence(); |
| 1255 | chunk->c_Next = bchunk; |
| 1256 | cpu_sfence(); |
| 1257 | |
| 1258 | if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, chunk)) |
| 1259 | break; |
| 1260 | } |
| 1261 | |
| 1262 | /* |
| 1263 | * We have to signal the remote cpu if our actions will cause |
| 1264 | * the remote zone to be placed back on ZoneAry so it can |
| 1265 | * move the zone back on. |
| 1266 | * |
| 1267 | * We only need to deal with NULL->non-NULL RChunk transitions |
| 1268 | * and only if z_RSignal is set. We interlock by reading rsignal |
| 1269 | * before adding our chunk to RChunks. This should result in |
| 1270 | * virtually no IPI traffic. |
| 1271 | * |
| 1272 | * We can use a passive IPI to reduce overhead even further. |
| 1273 | */ |
| 1274 | if (bchunk == NULL && rsignal) { |
| 1275 | logmemory(free_request, ptr, type, (unsigned long)z->z_ChunkSize, 0); |
| 1276 | lwkt_send_ipiq_passive(z->z_CpuGd, kfree_remote, z); |
| 1277 | /* z can get ripped out from under us from this point on */ |
| 1278 | } else if (rsignal) { |
| 1279 | atomic_subtract_int(&z->z_RCount, 1); |
| 1280 | /* z can get ripped out from under us from this point on */ |
| 1281 | } |
| 1282 | #else |
| 1283 | panic("Corrupt SLZone"); |
| 1284 | #endif |
| 1285 | logmemory_quick(free_end); |
| 1286 | return; |
| 1287 | } |
| 1288 | |
| 1289 | /* |
| 1290 | * kfree locally |
| 1291 | */ |
| 1292 | logmemory(free_chunk, ptr, type, (unsigned long)z->z_ChunkSize, 0); |
| 1293 | |
| 1294 | crit_enter(); |
| 1295 | chunk = ptr; |
| 1296 | chunk_mark_free(z, chunk); |
| 1297 | |
| 1298 | /* |
| 1299 | * Put weird data into the memory to detect modifications after freeing, |
| 1300 | * illegal pointer use after freeing (we should fault on the odd address), |
| 1301 | * and so forth. XXX needs more work, see the old malloc code. |
| 1302 | */ |
| 1303 | #ifdef INVARIANTS |
| 1304 | if (z->z_ChunkSize < sizeof(weirdary)) |
| 1305 | bcopy(weirdary, chunk, z->z_ChunkSize); |
| 1306 | else |
| 1307 | bcopy(weirdary, chunk, sizeof(weirdary)); |
| 1308 | #endif |
| 1309 | |
| 1310 | /* |
| 1311 | * Add this free non-zero'd chunk to a linked list for reuse. Add |
| 1312 | * to the front of the linked list so it is more likely to be |
| 1313 | * reallocated, since it is already in our L1 cache. |
| 1314 | */ |
| 1315 | #ifdef INVARIANTS |
| 1316 | if ((vm_offset_t)chunk < KvaStart || (vm_offset_t)chunk >= KvaEnd) |
| 1317 | panic("BADFREE %p", chunk); |
| 1318 | #endif |
| 1319 | chunk->c_Next = z->z_LChunks; |
| 1320 | z->z_LChunks = chunk; |
| 1321 | if (chunk->c_Next == NULL) |
| 1322 | z->z_LChunksp = &chunk->c_Next; |
| 1323 | |
| 1324 | #ifdef INVARIANTS |
| 1325 | if (chunk->c_Next && (vm_offset_t)chunk->c_Next < KvaStart) |
| 1326 | panic("BADFREE2"); |
| 1327 | #endif |
| 1328 | |
| 1329 | /* |
| 1330 | * Bump the number of free chunks. If it becomes non-zero the zone |
| 1331 | * must be added back onto the appropriate list. |
| 1332 | */ |
| 1333 | if (z->z_NFree++ == 0) { |
| 1334 | z->z_Next = slgd->ZoneAry[z->z_ZoneIndex]; |
| 1335 | slgd->ZoneAry[z->z_ZoneIndex] = z; |
| 1336 | } |
| 1337 | |
| 1338 | --type->ks_inuse[z->z_Cpu]; |
| 1339 | type->ks_memuse[z->z_Cpu] -= z->z_ChunkSize; |
| 1340 | |
| 1341 | /* |
| 1342 | * If the zone becomes totally free, and there are other zones we |
| 1343 | * can allocate from, move this zone to the FreeZones list. Since |
| 1344 | * this code can be called from an IPI callback, do *NOT* try to mess |
| 1345 | * with kernel_map here. Hysteresis will be performed at malloc() time. |
| 1346 | */ |
| 1347 | if (z->z_NFree == z->z_NMax && |
| 1348 | (z->z_Next || slgd->ZoneAry[z->z_ZoneIndex] != z) && |
| 1349 | z->z_RCount == 0 |
| 1350 | ) { |
| 1351 | SLZone **pz; |
| 1352 | int *kup; |
| 1353 | |
| 1354 | for (pz = &slgd->ZoneAry[z->z_ZoneIndex]; z != *pz; pz = &(*pz)->z_Next) |
| 1355 | ; |
| 1356 | *pz = z->z_Next; |
| 1357 | z->z_Magic = -1; |
| 1358 | z->z_Next = slgd->FreeZones; |
| 1359 | slgd->FreeZones = z; |
| 1360 | ++slgd->NFreeZones; |
| 1361 | kup = btokup(z); |
| 1362 | *kup = 0; |
| 1363 | } |
| 1364 | logmemory_quick(free_end); |
| 1365 | crit_exit(); |
| 1366 | } |
| 1367 | |
| 1368 | #if defined(INVARIANTS) |
| 1369 | |
| 1370 | /* |
| 1371 | * Helper routines for sanity checks |
| 1372 | */ |
| 1373 | static |
| 1374 | void |
| 1375 | chunk_mark_allocated(SLZone *z, void *chunk) |
| 1376 | { |
| 1377 | int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize; |
| 1378 | __uint32_t *bitptr; |
| 1379 | |
| 1380 | KKASSERT((((intptr_t)chunk ^ (intptr_t)z) & ZoneMask) == 0); |
| 1381 | KASSERT(bitdex >= 0 && bitdex < z->z_NMax, |
| 1382 | ("memory chunk %p bit index %d is illegal", chunk, bitdex)); |
| 1383 | bitptr = &z->z_Bitmap[bitdex >> 5]; |
| 1384 | bitdex &= 31; |
| 1385 | KASSERT((*bitptr & (1 << bitdex)) == 0, |
| 1386 | ("memory chunk %p is already allocated!", chunk)); |
| 1387 | *bitptr |= 1 << bitdex; |
| 1388 | } |
| 1389 | |
| 1390 | static |
| 1391 | void |
| 1392 | chunk_mark_free(SLZone *z, void *chunk) |
| 1393 | { |
| 1394 | int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize; |
| 1395 | __uint32_t *bitptr; |
| 1396 | |
| 1397 | KKASSERT((((intptr_t)chunk ^ (intptr_t)z) & ZoneMask) == 0); |
| 1398 | KASSERT(bitdex >= 0 && bitdex < z->z_NMax, |
| 1399 | ("memory chunk %p bit index %d is illegal!", chunk, bitdex)); |
| 1400 | bitptr = &z->z_Bitmap[bitdex >> 5]; |
| 1401 | bitdex &= 31; |
| 1402 | KASSERT((*bitptr & (1 << bitdex)) != 0, |
| 1403 | ("memory chunk %p is already free!", chunk)); |
| 1404 | *bitptr &= ~(1 << bitdex); |
| 1405 | } |
| 1406 | |
| 1407 | #endif |
| 1408 | |
| 1409 | /* |
| 1410 | * kmem_slab_alloc() |
| 1411 | * |
| 1412 | * Directly allocate and wire kernel memory in PAGE_SIZE chunks with the |
| 1413 | * specified alignment. M_* flags are expected in the flags field. |
| 1414 | * |
| 1415 | * Alignment must be a multiple of PAGE_SIZE. |
| 1416 | * |
| 1417 | * NOTE! XXX For the moment we use vm_map_entry_reserve/release(), |
| 1418 | * but when we move zalloc() over to use this function as its backend |
| 1419 | * we will have to switch to kreserve/krelease and call reserve(0) |
| 1420 | * after the new space is made available. |
| 1421 | * |
| 1422 | * Interrupt code which has preempted other code is not allowed to |
| 1423 | * use PQ_CACHE pages. However, if an interrupt thread is run |
| 1424 | * non-preemptively or blocks and then runs non-preemptively, then |
| 1425 | * it is free to use PQ_CACHE pages. <--- may not apply any longer XXX |
| 1426 | */ |
| 1427 | static void * |
| 1428 | kmem_slab_alloc(vm_size_t size, vm_offset_t align, int flags) |
| 1429 | { |
| 1430 | vm_size_t i; |
| 1431 | vm_offset_t addr; |
| 1432 | int count, vmflags, base_vmflags; |
| 1433 | vm_page_t mbase = NULL; |
| 1434 | vm_page_t m; |
| 1435 | thread_t td; |
| 1436 | |
| 1437 | size = round_page(size); |
| 1438 | addr = vm_map_min(&kernel_map); |
| 1439 | |
| 1440 | count = vm_map_entry_reserve(MAP_RESERVE_COUNT); |
| 1441 | crit_enter(); |
| 1442 | vm_map_lock(&kernel_map); |
| 1443 | if (vm_map_findspace(&kernel_map, addr, size, align, 0, &addr)) { |
| 1444 | vm_map_unlock(&kernel_map); |
| 1445 | if ((flags & M_NULLOK) == 0) |
| 1446 | panic("kmem_slab_alloc(): kernel_map ran out of space!"); |
| 1447 | vm_map_entry_release(count); |
| 1448 | crit_exit(); |
| 1449 | return(NULL); |
| 1450 | } |
| 1451 | |
| 1452 | /* |
| 1453 | * kernel_object maps 1:1 to kernel_map. |
| 1454 | */ |
| 1455 | vm_object_hold(&kernel_object); |
| 1456 | vm_object_reference_locked(&kernel_object); |
| 1457 | vm_map_insert(&kernel_map, &count, |
| 1458 | &kernel_object, addr, addr, addr + size, |
| 1459 | VM_MAPTYPE_NORMAL, |
| 1460 | VM_PROT_ALL, VM_PROT_ALL, |
| 1461 | 0); |
| 1462 | vm_object_drop(&kernel_object); |
| 1463 | vm_map_set_wired_quick(&kernel_map, addr, size, &count); |
| 1464 | vm_map_unlock(&kernel_map); |
| 1465 | |
| 1466 | td = curthread; |
| 1467 | |
| 1468 | base_vmflags = 0; |
| 1469 | if (flags & M_ZERO) |
| 1470 | base_vmflags |= VM_ALLOC_ZERO; |
| 1471 | if (flags & M_USE_RESERVE) |
| 1472 | base_vmflags |= VM_ALLOC_SYSTEM; |
| 1473 | if (flags & M_USE_INTERRUPT_RESERVE) |
| 1474 | base_vmflags |= VM_ALLOC_INTERRUPT; |
| 1475 | if ((flags & (M_RNOWAIT|M_WAITOK)) == 0) { |
| 1476 | panic("kmem_slab_alloc: bad flags %08x (%p)", |
| 1477 | flags, ((int **)&size)[-1]); |
| 1478 | } |
| 1479 | |
| 1480 | /* |
| 1481 | * Allocate the pages. Do not mess with the PG_ZERO flag or map |
| 1482 | * them yet. VM_ALLOC_NORMAL can only be set if we are not preempting. |
| 1483 | * |
| 1484 | * VM_ALLOC_SYSTEM is automatically set if we are preempting and |
| 1485 | * M_WAITOK was specified as an alternative (i.e. M_USE_RESERVE is |
| 1486 | * implied in this case), though I'm not sure if we really need to |
| 1487 | * do that. |
| 1488 | */ |
| 1489 | vmflags = base_vmflags; |
| 1490 | if (flags & M_WAITOK) { |
| 1491 | if (td->td_preempted) |
| 1492 | vmflags |= VM_ALLOC_SYSTEM; |
| 1493 | else |
| 1494 | vmflags |= VM_ALLOC_NORMAL; |
| 1495 | } |
| 1496 | |
| 1497 | vm_object_hold(&kernel_object); |
| 1498 | for (i = 0; i < size; i += PAGE_SIZE) { |
| 1499 | m = vm_page_alloc(&kernel_object, OFF_TO_IDX(addr + i), vmflags); |
| 1500 | if (i == 0) |
| 1501 | mbase = m; |
| 1502 | |
| 1503 | /* |
| 1504 | * If the allocation failed we either return NULL or we retry. |
| 1505 | * |
| 1506 | * If M_WAITOK is specified we wait for more memory and retry. |
| 1507 | * If M_WAITOK is specified from a preemption we yield instead of |
| 1508 | * wait. Livelock will not occur because the interrupt thread |
| 1509 | * will not be preempting anyone the second time around after the |
| 1510 | * yield. |
| 1511 | */ |
| 1512 | if (m == NULL) { |
| 1513 | if (flags & M_WAITOK) { |
| 1514 | if (td->td_preempted) { |
| 1515 | lwkt_switch(); |
| 1516 | } else { |
| 1517 | vm_wait(0); |
| 1518 | } |
| 1519 | i -= PAGE_SIZE; /* retry */ |
| 1520 | continue; |
| 1521 | } |
| 1522 | break; |
| 1523 | } |
| 1524 | } |
| 1525 | |
| 1526 | /* |
| 1527 | * Check and deal with an allocation failure |
| 1528 | */ |
| 1529 | if (i != size) { |
| 1530 | while (i != 0) { |
| 1531 | i -= PAGE_SIZE; |
| 1532 | m = vm_page_lookup(&kernel_object, OFF_TO_IDX(addr + i)); |
| 1533 | /* page should already be busy */ |
| 1534 | vm_page_free(m); |
| 1535 | } |
| 1536 | vm_map_lock(&kernel_map); |
| 1537 | vm_map_delete(&kernel_map, addr, addr + size, &count); |
| 1538 | vm_map_unlock(&kernel_map); |
| 1539 | vm_object_drop(&kernel_object); |
| 1540 | |
| 1541 | vm_map_entry_release(count); |
| 1542 | crit_exit(); |
| 1543 | return(NULL); |
| 1544 | } |
| 1545 | |
| 1546 | /* |
| 1547 | * Success! |
| 1548 | * |
| 1549 | * NOTE: The VM pages are still busied. mbase points to the first one |
| 1550 | * but we have to iterate via vm_page_next() |
| 1551 | */ |
| 1552 | vm_object_drop(&kernel_object); |
| 1553 | crit_exit(); |
| 1554 | |
| 1555 | /* |
| 1556 | * Enter the pages into the pmap and deal with PG_ZERO and M_ZERO. |
| 1557 | */ |
| 1558 | m = mbase; |
| 1559 | i = 0; |
| 1560 | |
| 1561 | while (i < size) { |
| 1562 | /* |
| 1563 | * page should already be busy |
| 1564 | */ |
| 1565 | m->valid = VM_PAGE_BITS_ALL; |
| 1566 | vm_page_wire(m); |
| 1567 | pmap_enter(&kernel_pmap, addr + i, m, VM_PROT_ALL | VM_PROT_NOSYNC, |
| 1568 | 1, NULL); |
| 1569 | if ((m->flags & PG_ZERO) == 0 && (flags & M_ZERO)) |
| 1570 | bzero((char *)addr + i, PAGE_SIZE); |
| 1571 | vm_page_flag_clear(m, PG_ZERO); |
| 1572 | KKASSERT(m->flags & (PG_WRITEABLE | PG_MAPPED)); |
| 1573 | vm_page_flag_set(m, PG_REFERENCED); |
| 1574 | vm_page_wakeup(m); |
| 1575 | |
| 1576 | i += PAGE_SIZE; |
| 1577 | vm_object_hold(&kernel_object); |
| 1578 | m = vm_page_next(m); |
| 1579 | vm_object_drop(&kernel_object); |
| 1580 | } |
| 1581 | smp_invltlb(); |
| 1582 | vm_map_entry_release(count); |
| 1583 | return((void *)addr); |
| 1584 | } |
| 1585 | |
| 1586 | /* |
| 1587 | * kmem_slab_free() |
| 1588 | */ |
| 1589 | static void |
| 1590 | kmem_slab_free(void *ptr, vm_size_t size) |
| 1591 | { |
| 1592 | crit_enter(); |
| 1593 | vm_map_remove(&kernel_map, (vm_offset_t)ptr, (vm_offset_t)ptr + size); |
| 1594 | crit_exit(); |
| 1595 | } |
| 1596 | |
| 1597 | void * |
| 1598 | kmalloc_cachealign(unsigned long size_alloc, struct malloc_type *type, |
| 1599 | int flags) |
| 1600 | { |
| 1601 | #if (__VM_CACHELINE_SIZE == 32) |
| 1602 | #define CAN_CACHEALIGN(sz) ((sz) >= 256) |
| 1603 | #elif (__VM_CACHELINE_SIZE == 64) |
| 1604 | #define CAN_CACHEALIGN(sz) ((sz) >= 512) |
| 1605 | #elif (__VM_CACHELINE_SIZE == 128) |
| 1606 | #define CAN_CACHEALIGN(sz) ((sz) >= 1024) |
| 1607 | #else |
| 1608 | #error "unsupported cacheline size" |
| 1609 | #endif |
| 1610 | |
| 1611 | void *ret; |
| 1612 | |
| 1613 | if (size_alloc < __VM_CACHELINE_SIZE) |
| 1614 | size_alloc = __VM_CACHELINE_SIZE; |
| 1615 | else if (!CAN_CACHEALIGN(size_alloc)) |
| 1616 | flags |= M_POWEROF2; |
| 1617 | |
| 1618 | ret = kmalloc(size_alloc, type, flags); |
| 1619 | KASSERT(((uintptr_t)ret & (__VM_CACHELINE_SIZE - 1)) == 0, |
| 1620 | ("%p(%lu) not cacheline %d aligned", |
| 1621 | ret, size_alloc, __VM_CACHELINE_SIZE)); |
| 1622 | return ret; |
| 1623 | |
| 1624 | #undef CAN_CACHEALIGN |
| 1625 | } |