1 /* 2 * Copyright (c) 1987, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. 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 * $Id: kern_malloc.c,v 1.46 1998/07/29 17:38:14 bde Exp $ 35 */ 36 37 #include "opt_vm.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/kernel.h> 42 #define MALLOC_INSTANTIATE 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/vmmeter.h> 46 #include <sys/lock.h> 47 48 #include <vm/vm.h> 49 #include <vm/vm_param.h> 50 #include <vm/vm_kern.h> 51 #include <vm/vm_extern.h> 52 #include <vm/pmap.h> 53 #include <vm/vm_map.h> 54 55 static void kmeminit __P((void *)); 56 static void malloc_init __P((struct malloc_type *)); 57 SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, kmeminit, NULL) 58 59 static MALLOC_DEFINE(M_FREE, "free", "should be on free list"); 60 61 static struct malloc_type *kmemstatistics = M_FREE; 62 static struct kmembuckets bucket[MINBUCKET + 16]; 63 static struct kmemusage *kmemusage; 64 static char *kmembase; 65 static char *kmemlimit; 66 static int vm_kmem_size; 67 68 #ifdef DIAGNOSTIC 69 /* 70 * This structure provides a set of masks to catch unaligned frees. 71 */ 72 static long addrmask[] = { 0, 73 0x00000001, 0x00000003, 0x00000007, 0x0000000f, 74 0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff, 75 0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff, 76 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff, 77 }; 78 79 /* 80 * The WEIRD_ADDR is used as known text to copy into free objects so 81 * that modifications after frees can be detected. 82 */ 83 #define WEIRD_ADDR 0xdeadc0de 84 #define MAX_COPY 64 85 86 /* 87 * Normally the first word of the structure is used to hold the list 88 * pointer for free objects. However, when running with diagnostics, 89 * we use the third and fourth fields, so as to catch modifications 90 * in the most commonly trashed first two words. 91 */ 92 struct freelist { 93 long spare0; 94 struct malloc_type *type; 95 long spare1; 96 caddr_t next; 97 }; 98 #else /* !DIAGNOSTIC */ 99 struct freelist { 100 caddr_t next; 101 }; 102 #endif /* DIAGNOSTIC */ 103 104 /* 105 * Allocate a block of memory 106 */ 107 void * 108 malloc(size, type, flags) 109 unsigned long size; 110 struct malloc_type *type; 111 int flags; 112 { 113 register struct kmembuckets *kbp; 114 register struct kmemusage *kup; 115 register struct freelist *freep; 116 long indx, npg, allocsize; 117 int s; 118 caddr_t va, cp, savedlist; 119 #ifdef DIAGNOSTIC 120 long *end, *lp; 121 int copysize; 122 char *savedtype; 123 #endif 124 register struct malloc_type *ksp = type; 125 126 if (!type->ks_next) 127 malloc_init(type); 128 129 indx = BUCKETINDX(size); 130 kbp = &bucket[indx]; 131 s = splmem(); 132 while (ksp->ks_memuse >= ksp->ks_limit) { 133 if (flags & M_NOWAIT) { 134 splx(s); 135 return ((void *) NULL); 136 } 137 if (ksp->ks_limblocks < 65535) 138 ksp->ks_limblocks++; 139 tsleep((caddr_t)ksp, PSWP+2, type->ks_shortdesc, 0); 140 } 141 ksp->ks_size |= 1 << indx; 142 #ifdef DIAGNOSTIC 143 copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY; 144 #endif 145 if (kbp->kb_next == NULL) { 146 kbp->kb_last = NULL; 147 if (size > MAXALLOCSAVE) 148 allocsize = roundup(size, PAGE_SIZE); 149 else 150 allocsize = 1 << indx; 151 npg = btoc(allocsize); 152 va = (caddr_t) kmem_malloc(kmem_map, (vm_size_t)ctob(npg), flags); 153 if (va == NULL) { 154 splx(s); 155 return ((void *) NULL); 156 } 157 kbp->kb_total += kbp->kb_elmpercl; 158 kup = btokup(va); 159 kup->ku_indx = indx; 160 if (allocsize > MAXALLOCSAVE) { 161 if (npg > 65535) 162 panic("malloc: allocation too large"); 163 kup->ku_pagecnt = npg; 164 ksp->ks_memuse += allocsize; 165 goto out; 166 } 167 kup->ku_freecnt = kbp->kb_elmpercl; 168 kbp->kb_totalfree += kbp->kb_elmpercl; 169 /* 170 * Just in case we blocked while allocating memory, 171 * and someone else also allocated memory for this 172 * bucket, don't assume the list is still empty. 173 */ 174 savedlist = kbp->kb_next; 175 kbp->kb_next = cp = va + (npg * PAGE_SIZE) - allocsize; 176 for (;;) { 177 freep = (struct freelist *)cp; 178 #ifdef DIAGNOSTIC 179 /* 180 * Copy in known text to detect modification 181 * after freeing. 182 */ 183 end = (long *)&cp[copysize]; 184 for (lp = (long *)cp; lp < end; lp++) 185 *lp = WEIRD_ADDR; 186 freep->type = M_FREE; 187 #endif /* DIAGNOSTIC */ 188 if (cp <= va) 189 break; 190 cp -= allocsize; 191 freep->next = cp; 192 } 193 freep->next = savedlist; 194 if (kbp->kb_last == NULL) 195 kbp->kb_last = (caddr_t)freep; 196 } 197 va = kbp->kb_next; 198 kbp->kb_next = ((struct freelist *)va)->next; 199 #ifdef DIAGNOSTIC 200 freep = (struct freelist *)va; 201 savedtype = (char *) type->ks_shortdesc; 202 #if BYTE_ORDER == BIG_ENDIAN 203 freep->type = (struct malloc_type *)WEIRD_ADDR >> 16; 204 #endif 205 #if BYTE_ORDER == LITTLE_ENDIAN 206 freep->type = (struct malloc_type *)WEIRD_ADDR; 207 #endif 208 if ((intptr_t)(void *)&freep->next & 0x2) 209 freep->next = (caddr_t)((WEIRD_ADDR >> 16)|(WEIRD_ADDR << 16)); 210 else 211 freep->next = (caddr_t)WEIRD_ADDR; 212 end = (long *)&va[copysize]; 213 for (lp = (long *)va; lp < end; lp++) { 214 if (*lp == WEIRD_ADDR) 215 continue; 216 printf("%s %ld of object %p size %lu %s %s (0x%lx != 0x%lx)\n", 217 "Data modified on freelist: word", 218 (long)(lp - (long *)va), (void *)va, size, 219 "previous type", savedtype, *lp, (u_long)WEIRD_ADDR); 220 break; 221 } 222 freep->spare0 = 0; 223 #endif /* DIAGNOSTIC */ 224 kup = btokup(va); 225 if (kup->ku_indx != indx) 226 panic("malloc: wrong bucket"); 227 if (kup->ku_freecnt == 0) 228 panic("malloc: lost data"); 229 kup->ku_freecnt--; 230 kbp->kb_totalfree--; 231 ksp->ks_memuse += 1 << indx; 232 out: 233 kbp->kb_calls++; 234 ksp->ks_inuse++; 235 ksp->ks_calls++; 236 if (ksp->ks_memuse > ksp->ks_maxused) 237 ksp->ks_maxused = ksp->ks_memuse; 238 splx(s); 239 return ((void *) va); 240 } 241 242 /* 243 * Free a block of memory allocated by malloc. 244 */ 245 void 246 free(addr, type) 247 void *addr; 248 struct malloc_type *type; 249 { 250 register struct kmembuckets *kbp; 251 register struct kmemusage *kup; 252 register struct freelist *freep; 253 long size; 254 int s; 255 #ifdef DIAGNOSTIC 256 struct freelist *fp; 257 long *end, *lp, alloc, copysize; 258 #endif 259 register struct malloc_type *ksp = type; 260 261 if (!type->ks_next) 262 panic("freeing with unknown type (%s)", type->ks_shortdesc); 263 264 #ifdef DIAGNOSTIC 265 if ((char *)addr < kmembase || (char *)addr >= kmemlimit) { 266 panic("free: address %p out of range", (void *)addr); 267 } 268 #endif 269 kup = btokup(addr); 270 size = 1 << kup->ku_indx; 271 kbp = &bucket[kup->ku_indx]; 272 s = splmem(); 273 #ifdef DIAGNOSTIC 274 /* 275 * Check for returns of data that do not point to the 276 * beginning of the allocation. 277 */ 278 if (size > PAGE_SIZE) 279 alloc = addrmask[BUCKETINDX(PAGE_SIZE)]; 280 else 281 alloc = addrmask[kup->ku_indx]; 282 if (((uintptr_t)(void *)addr & alloc) != 0) 283 panic("free: unaligned addr %p, size %ld, type %s, mask %ld", 284 (void *)addr, size, type->ks_shortdesc, alloc); 285 #endif /* DIAGNOSTIC */ 286 if (size > MAXALLOCSAVE) { 287 kmem_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt)); 288 size = kup->ku_pagecnt << PAGE_SHIFT; 289 ksp->ks_memuse -= size; 290 kup->ku_indx = 0; 291 kup->ku_pagecnt = 0; 292 if (ksp->ks_memuse + size >= ksp->ks_limit && 293 ksp->ks_memuse < ksp->ks_limit) 294 wakeup((caddr_t)ksp); 295 ksp->ks_inuse--; 296 kbp->kb_total -= 1; 297 splx(s); 298 return; 299 } 300 freep = (struct freelist *)addr; 301 #ifdef DIAGNOSTIC 302 /* 303 * Check for multiple frees. Use a quick check to see if 304 * it looks free before laboriously searching the freelist. 305 */ 306 if (freep->spare0 == WEIRD_ADDR) { 307 fp = (struct freelist *)kbp->kb_next; 308 while (fp) { 309 if (fp->spare0 != WEIRD_ADDR) { 310 printf("trashed free item %p\n", fp); 311 panic("free: free item modified"); 312 } else if (addr == (caddr_t)fp) { 313 printf("multiple freed item %p\n", addr); 314 panic("free: multiple free"); 315 } 316 fp = (struct freelist *)fp->next; 317 } 318 } 319 /* 320 * Copy in known text to detect modification after freeing 321 * and to make it look free. Also, save the type being freed 322 * so we can list likely culprit if modification is detected 323 * when the object is reallocated. 324 */ 325 copysize = size < MAX_COPY ? size : MAX_COPY; 326 end = (long *)&((caddr_t)addr)[copysize]; 327 for (lp = (long *)addr; lp < end; lp++) 328 *lp = WEIRD_ADDR; 329 freep->type = type; 330 #endif /* DIAGNOSTIC */ 331 kup->ku_freecnt++; 332 if (kup->ku_freecnt >= kbp->kb_elmpercl) 333 if (kup->ku_freecnt > kbp->kb_elmpercl) 334 panic("free: multiple frees"); 335 else if (kbp->kb_totalfree > kbp->kb_highwat) 336 kbp->kb_couldfree++; 337 kbp->kb_totalfree++; 338 ksp->ks_memuse -= size; 339 if (ksp->ks_memuse + size >= ksp->ks_limit && 340 ksp->ks_memuse < ksp->ks_limit) 341 wakeup((caddr_t)ksp); 342 ksp->ks_inuse--; 343 #ifdef OLD_MALLOC_MEMORY_POLICY 344 if (kbp->kb_next == NULL) 345 kbp->kb_next = addr; 346 else 347 ((struct freelist *)kbp->kb_last)->next = addr; 348 freep->next = NULL; 349 kbp->kb_last = addr; 350 #else 351 /* 352 * Return memory to the head of the queue for quick reuse. This 353 * can improve performance by improving the probability of the 354 * item being in the cache when it is reused. 355 */ 356 if (kbp->kb_next == NULL) { 357 kbp->kb_next = addr; 358 kbp->kb_last = addr; 359 freep->next = NULL; 360 } else { 361 freep->next = kbp->kb_next; 362 kbp->kb_next = addr; 363 } 364 #endif 365 splx(s); 366 } 367 368 /* 369 * Initialize the kernel memory allocator 370 */ 371 /* ARGSUSED*/ 372 static void 373 kmeminit(dummy) 374 void *dummy; 375 { 376 register long indx; 377 int npg; 378 int mem_size; 379 380 #if ((MAXALLOCSAVE & (MAXALLOCSAVE - 1)) != 0) 381 #error "kmeminit: MAXALLOCSAVE not power of 2" 382 #endif 383 #if (MAXALLOCSAVE > MINALLOCSIZE * 32768) 384 #error "kmeminit: MAXALLOCSAVE too big" 385 #endif 386 #if (MAXALLOCSAVE < PAGE_SIZE) 387 #error "kmeminit: MAXALLOCSAVE too small" 388 #endif 389 390 /* 391 * Try to auto-tune the kernel memory size, so that it is 392 * more applicable for a wider range of machine sizes. 393 * On an X86, a VM_KMEM_SIZE_SCALE value of 4 is good, while 394 * a VM_KMEM_SIZE of 12MB is a fair compromise. The 395 * VM_KMEM_SIZE_MAX is dependent on the maximum KVA space 396 * available, and on an X86 with a total KVA space of 256MB, 397 * try to keep VM_KMEM_SIZE_MAX at 80MB or below. 398 * 399 * Note that the kmem_map is also used by the zone allocator, 400 * so make sure that there is enough space. 401 */ 402 vm_kmem_size = VM_KMEM_SIZE; 403 mem_size = cnt.v_page_count * PAGE_SIZE; 404 405 #if defined(VM_KMEM_SIZE_SCALE) 406 if ((mem_size / VM_KMEM_SIZE_SCALE) > vm_kmem_size) 407 vm_kmem_size = mem_size / VM_KMEM_SIZE_SCALE; 408 #endif 409 410 #if defined(VM_KMEM_SIZE_MAX) 411 if (vm_kmem_size >= VM_KMEM_SIZE_MAX) 412 vm_kmem_size = VM_KMEM_SIZE_MAX; 413 #endif 414 415 if (vm_kmem_size > 2 * (cnt.v_page_count * PAGE_SIZE)) 416 vm_kmem_size = 2 * (cnt.v_page_count * PAGE_SIZE); 417 418 npg = (nmbufs * MSIZE + nmbclusters * MCLBYTES + vm_kmem_size) 419 / PAGE_SIZE; 420 421 kmemusage = (struct kmemusage *) kmem_alloc(kernel_map, 422 (vm_size_t)(npg * sizeof(struct kmemusage))); 423 kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase, 424 (vm_offset_t *)&kmemlimit, (vm_size_t)(npg * PAGE_SIZE)); 425 kmem_map->system_map = 1; 426 for (indx = 0; indx < MINBUCKET + 16; indx++) { 427 if (1 << indx >= PAGE_SIZE) 428 bucket[indx].kb_elmpercl = 1; 429 else 430 bucket[indx].kb_elmpercl = PAGE_SIZE / (1 << indx); 431 bucket[indx].kb_highwat = 5 * bucket[indx].kb_elmpercl; 432 } 433 } 434 435 static void 436 malloc_init(type) 437 struct malloc_type *type; 438 { 439 int npg; 440 int mem_size; 441 442 if (type->ks_magic != M_MAGIC) 443 panic("malloc type lacks magic"); 444 445 if (cnt.v_page_count == 0) 446 panic("malloc_init not allowed before vm init"); 447 448 /* 449 * The default limits for each malloc region is 1/2 of the 450 * malloc portion of the kmem map size. 451 */ 452 type->ks_limit = vm_kmem_size / 2; 453 type->ks_next = kmemstatistics; 454 kmemstatistics = type; 455 } 456