1 /* 2 * Copyright (c) 2005 Jeffrey M. Hsu. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Jeffrey M. Hsu. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of The DragonFly Project nor the names of its 16 * contributors may be used to endorse or promote products derived 17 * from this software without specific, prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 23 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 25 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 27 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 28 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 29 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $DragonFly: src/sys/kern/kern_objcache.c,v 1.16 2007/01/07 04:06:51 y0netan1 Exp $ 33 */ 34 35 #include <sys/param.h> 36 #include <sys/kernel.h> 37 #include <sys/systm.h> 38 #include <sys/callout.h> 39 #include <sys/globaldata.h> 40 #include <sys/malloc.h> 41 #include <sys/queue.h> 42 #include <sys/objcache.h> 43 #include <sys/spinlock.h> 44 #include <sys/thread.h> 45 #include <sys/thread2.h> 46 #include <sys/spinlock2.h> 47 48 static MALLOC_DEFINE(M_OBJCACHE, "objcache", "Object Cache"); 49 static MALLOC_DEFINE(M_OBJMAG, "objcache magazine", "Object Cache Magazine"); 50 51 #define INITIAL_MAG_CAPACITY 256 52 53 struct magazine { 54 int rounds; 55 int capacity; 56 int cleaning; 57 SLIST_ENTRY(magazine) nextmagazine; 58 void *objects[]; 59 }; 60 61 SLIST_HEAD(magazinelist, magazine); 62 63 /* 64 * per-cluster cache of magazines 65 * 66 * All fields in this structure are protected by the spinlock. 67 */ 68 struct magazinedepot { 69 /* 70 * The per-cpu object caches only exchanges completely full or 71 * completely empty magazines with the depot layer, so only have 72 * to cache these two types of magazines. 73 */ 74 struct magazinelist fullmagazines; 75 struct magazinelist emptymagazines; 76 int magcapacity; 77 78 /* protect this structure */ 79 struct spinlock spin; 80 81 /* magazines not yet allocated towards limit */ 82 int unallocated_objects; 83 84 /* infrequently used fields */ 85 int waiting; /* waiting for another cpu to 86 * return a full magazine to 87 * the depot */ 88 int contested; /* depot contention count */ 89 }; 90 91 /* 92 * per-cpu object cache 93 * All fields in this structure are protected by crit_enter(). 94 */ 95 struct percpu_objcache { 96 struct magazine *loaded_magazine; /* active magazine */ 97 struct magazine *previous_magazine; /* backup magazine */ 98 99 /* statistics */ 100 int gets_cumulative; /* total calls to get */ 101 int gets_null; /* objcache_get returned NULL */ 102 int puts_cumulative; /* total calls to put */ 103 int puts_othercluster; /* returned to other cluster */ 104 105 /* infrequently used fields */ 106 int waiting; /* waiting for a thread on this cpu to 107 * return an obj to the per-cpu cache */ 108 }; 109 110 /* only until we have NUMA cluster topology information XXX */ 111 #define MAXCLUSTERS 1 112 #define myclusterid 0 113 #define CLUSTER_OF(obj) 0 114 115 /* 116 * Two-level object cache consisting of NUMA cluster-level depots of 117 * fully loaded or completely empty magazines and cpu-level caches of 118 * individual objects. 119 */ 120 struct objcache { 121 char *name; 122 123 /* object constructor and destructor from blank storage */ 124 objcache_ctor_fn *ctor; 125 objcache_dtor_fn *dtor; 126 void *private; 127 128 /* interface to underlying allocator */ 129 objcache_alloc_fn *alloc; 130 objcache_free_fn *free; 131 void *allocator_args; 132 133 SLIST_ENTRY(objcache) oc_next; 134 135 /* NUMA-cluster level caches */ 136 struct magazinedepot depot[MAXCLUSTERS]; 137 138 struct percpu_objcache cache_percpu[]; /* per-cpu caches */ 139 }; 140 141 static struct spinlock objcachelist_spin; 142 static SLIST_HEAD(objcachelist, objcache) allobjcaches; 143 144 static struct magazine * 145 mag_alloc(int capacity) 146 { 147 struct magazine *mag; 148 149 mag = kmalloc(__offsetof(struct magazine, objects[capacity]), 150 M_OBJMAG, M_INTWAIT | M_ZERO); 151 mag->capacity = capacity; 152 mag->rounds = 0; 153 mag->cleaning = 0; 154 return (mag); 155 } 156 157 /* 158 * Utility routine for objects that don't require any de-construction. 159 */ 160 161 static void 162 null_dtor(void *obj, void *private) 163 { 164 /* do nothing */ 165 } 166 167 static boolean_t 168 null_ctor(void *obj, void *private, int ocflags) 169 { 170 return TRUE; 171 } 172 173 /* 174 * Create an object cache. 175 */ 176 struct objcache * 177 objcache_create(const char *name, int cluster_limit, int mag_capacity, 178 objcache_ctor_fn *ctor, objcache_dtor_fn *dtor, void *private, 179 objcache_alloc_fn *alloc, objcache_free_fn *free, 180 void *allocator_args) 181 { 182 struct objcache *oc; 183 struct magazinedepot *depot; 184 int cpuid; 185 186 /* allocate object cache structure */ 187 oc = kmalloc(__offsetof(struct objcache, cache_percpu[ncpus]), 188 M_OBJCACHE, M_WAITOK | M_ZERO); 189 oc->name = kstrdup(name, M_TEMP); 190 oc->ctor = ctor ? ctor : null_ctor; 191 oc->dtor = dtor ? dtor : null_dtor; 192 oc->private = private; 193 oc->free = free; 194 oc->allocator_args = allocator_args; 195 196 /* initialize depots */ 197 depot = &oc->depot[0]; 198 199 spin_init(&depot->spin); 200 SLIST_INIT(&depot->fullmagazines); 201 SLIST_INIT(&depot->emptymagazines); 202 203 if (mag_capacity == 0) 204 mag_capacity = INITIAL_MAG_CAPACITY; 205 depot->magcapacity = mag_capacity; 206 207 /* 208 * The cluster_limit must be sufficient to have three magazines per 209 * cpu. 210 */ 211 if (cluster_limit == 0) { 212 depot->unallocated_objects = -1; 213 } else { 214 if (cluster_limit < mag_capacity * ncpus * 3) 215 cluster_limit = mag_capacity * ncpus * 3; 216 depot->unallocated_objects = cluster_limit; 217 } 218 oc->alloc = alloc; 219 220 /* initialize per-cpu caches */ 221 for (cpuid = 0; cpuid < ncpus; cpuid++) { 222 struct percpu_objcache *cache_percpu = &oc->cache_percpu[cpuid]; 223 224 cache_percpu->loaded_magazine = mag_alloc(mag_capacity); 225 cache_percpu->previous_magazine = mag_alloc(mag_capacity); 226 } 227 spin_lock_wr(&objcachelist_spin); 228 SLIST_INSERT_HEAD(&allobjcaches, oc, oc_next); 229 spin_unlock_wr(&objcachelist_spin); 230 231 return (oc); 232 } 233 234 struct objcache * 235 objcache_create_simple(malloc_type_t mtype, size_t objsize) 236 { 237 struct objcache_malloc_args *margs; 238 struct objcache *oc; 239 240 margs = kmalloc(sizeof(*margs), M_OBJCACHE, M_WAITOK|M_ZERO); 241 margs->objsize = objsize; 242 margs->mtype = mtype; 243 oc = objcache_create(mtype->ks_shortdesc, 0, 0, 244 NULL, NULL, NULL, 245 objcache_malloc_alloc, objcache_malloc_free, 246 margs); 247 return (oc); 248 } 249 250 #define MAGAZINE_EMPTY(mag) (mag->rounds == 0) 251 #define MAGAZINE_NOTEMPTY(mag) (mag->rounds != 0) 252 #define MAGAZINE_FULL(mag) (mag->rounds == mag->capacity) 253 254 #define swap(x, y) ({ struct magazine *t = x; x = y; y = t; }) 255 256 /* 257 * Get an object from the object cache. 258 * 259 * WARNING! ocflags are only used when we have to go to the underlying 260 * allocator, so we cannot depend on flags such as M_ZERO. 261 */ 262 void * 263 objcache_get(struct objcache *oc, int ocflags) 264 { 265 struct percpu_objcache *cpucache = &oc->cache_percpu[mycpuid]; 266 struct magazine *loadedmag; 267 struct magazine *emptymag; 268 void *obj; 269 struct magazinedepot *depot; 270 271 KKASSERT((ocflags & M_ZERO) == 0); 272 crit_enter(); 273 ++cpucache->gets_cumulative; 274 275 retry: 276 /* 277 * Loaded magazine has an object. This is the hot path. 278 * It is lock-free and uses a critical section to block 279 * out interrupt handlers on the same processor. 280 */ 281 loadedmag = cpucache->loaded_magazine; 282 if (MAGAZINE_NOTEMPTY(loadedmag)) { 283 obj = loadedmag->objects[--loadedmag->rounds]; 284 crit_exit(); 285 return (obj); 286 } 287 288 /* Previous magazine has an object. */ 289 if (MAGAZINE_NOTEMPTY(cpucache->previous_magazine)) { 290 KKASSERT(cpucache->previous_magazine->cleaning + 291 cpucache->loaded_magazine->cleaning == 0); 292 swap(cpucache->loaded_magazine, cpucache->previous_magazine); 293 loadedmag = cpucache->loaded_magazine; 294 obj = loadedmag->objects[--loadedmag->rounds]; 295 crit_exit(); 296 return (obj); 297 } 298 299 /* 300 * Both magazines empty. Get a full magazine from the depot and 301 * move one of the empty ones to the depot. 302 * 303 * Obtain the depot spinlock. 304 * 305 * NOTE: Beyond this point, M_* flags are handled via oc->alloc() 306 */ 307 depot = &oc->depot[myclusterid]; 308 spin_lock_wr(&depot->spin); 309 310 /* 311 * Recheck the cpucache after obtaining the depot spinlock. This 312 * shouldn't be necessary now but don't take any chances. 313 */ 314 if (MAGAZINE_NOTEMPTY(cpucache->loaded_magazine) || 315 MAGAZINE_NOTEMPTY(cpucache->previous_magazine) 316 ) { 317 spin_unlock_wr(&depot->spin); 318 goto retry; 319 } 320 321 /* Check if depot has a full magazine. */ 322 if (!SLIST_EMPTY(&depot->fullmagazines)) { 323 emptymag = cpucache->previous_magazine; 324 cpucache->previous_magazine = cpucache->loaded_magazine; 325 cpucache->loaded_magazine = SLIST_FIRST(&depot->fullmagazines); 326 SLIST_REMOVE_HEAD(&depot->fullmagazines, nextmagazine); 327 328 /* 329 * Return emptymag to the depot. 330 */ 331 KKASSERT(MAGAZINE_EMPTY(emptymag)); 332 SLIST_INSERT_HEAD(&depot->emptymagazines, 333 emptymag, nextmagazine); 334 spin_unlock_wr(&depot->spin); 335 goto retry; 336 } 337 338 /* 339 * The depot does not have any non-empty magazines. If we have 340 * not hit our object limit we can allocate a new object using 341 * the back-end allocator. 342 * 343 * note: unallocated_objects can be initialized to -1, which has 344 * the effect of removing any allocation limits. 345 */ 346 if (depot->unallocated_objects) { 347 --depot->unallocated_objects; 348 spin_unlock_wr(&depot->spin); 349 crit_exit(); 350 351 obj = oc->alloc(oc->allocator_args, ocflags); 352 if (obj) { 353 if (oc->ctor(obj, oc->private, ocflags)) 354 return (obj); 355 oc->free(obj, oc->allocator_args); 356 spin_lock_wr(&depot->spin); 357 ++depot->unallocated_objects; 358 spin_unlock_wr(&depot->spin); 359 if (depot->waiting) 360 wakeup(depot); 361 obj = NULL; 362 } 363 if (obj == NULL) { 364 crit_enter(); 365 /* 366 * makes debugging easier when gets_cumulative does 367 * not include gets_null. 368 */ 369 ++cpucache->gets_null; 370 --cpucache->gets_cumulative; 371 crit_exit(); 372 } 373 return(obj); 374 } 375 376 /* 377 * Otherwise block if allowed to. 378 */ 379 if ((ocflags & (M_WAITOK|M_NULLOK)) == M_WAITOK) { 380 ++cpucache->waiting; 381 ++depot->waiting; 382 msleep(depot, &depot->spin, 0, "objcache_get", 0); 383 --cpucache->waiting; 384 --depot->waiting; 385 spin_unlock_wr(&depot->spin); 386 goto retry; 387 } 388 389 /* 390 * Otherwise fail 391 */ 392 ++cpucache->gets_null; 393 --cpucache->gets_cumulative; 394 crit_exit(); 395 spin_unlock_wr(&depot->spin); 396 return (NULL); 397 } 398 399 /* 400 * Wrapper for malloc allocation routines. 401 */ 402 void * 403 objcache_malloc_alloc(void *allocator_args, int ocflags) 404 { 405 struct objcache_malloc_args *alloc_args = allocator_args; 406 407 return (kmalloc(alloc_args->objsize, alloc_args->mtype, 408 ocflags & OC_MFLAGS)); 409 } 410 411 void 412 objcache_malloc_free(void *obj, void *allocator_args) 413 { 414 struct objcache_malloc_args *alloc_args = allocator_args; 415 416 kfree(obj, alloc_args->mtype); 417 } 418 419 /* 420 * Wrapper for allocation policies that pre-allocate at initialization time 421 * and don't do run-time allocation. 422 */ 423 void * 424 objcache_nop_alloc(void *allocator_args, int ocflags) 425 { 426 return (NULL); 427 } 428 429 void 430 objcache_nop_free(void *obj, void *allocator_args) 431 { 432 } 433 434 /* 435 * Return an object to the object cache. 436 */ 437 void 438 objcache_put(struct objcache *oc, void *obj) 439 { 440 struct percpu_objcache *cpucache = &oc->cache_percpu[mycpuid]; 441 struct magazine *loadedmag; 442 struct magazinedepot *depot; 443 444 crit_enter(); 445 ++cpucache->puts_cumulative; 446 447 if (CLUSTER_OF(obj) != myclusterid) { 448 #ifdef notyet 449 /* use lazy IPI to send object to owning cluster XXX todo */ 450 ++cpucache->puts_othercluster; 451 crit_exit(); 452 return; 453 #endif 454 } 455 456 retry: 457 /* 458 * Free slot available in loaded magazine. This is the hot path. 459 * It is lock-free and uses a critical section to block out interrupt 460 * handlers on the same processor. 461 */ 462 loadedmag = cpucache->loaded_magazine; 463 if (!MAGAZINE_FULL(loadedmag)) { 464 loadedmag->objects[loadedmag->rounds++] = obj; 465 if (cpucache->waiting) 466 wakeup_mycpu(&oc->depot[myclusterid]); 467 crit_exit(); 468 return; 469 } 470 471 /* 472 * Current magazine full, but previous magazine has room. XXX 473 */ 474 if (!MAGAZINE_FULL(cpucache->previous_magazine)) { 475 KKASSERT(cpucache->previous_magazine->cleaning + 476 cpucache->loaded_magazine->cleaning == 0); 477 swap(cpucache->loaded_magazine, cpucache->previous_magazine); 478 loadedmag = cpucache->loaded_magazine; 479 loadedmag->objects[loadedmag->rounds++] = obj; 480 if (cpucache->waiting) 481 wakeup_mycpu(&oc->depot[myclusterid]); 482 crit_exit(); 483 return; 484 } 485 486 /* 487 * Both magazines full. Get an empty magazine from the depot and 488 * move a full loaded magazine to the depot. Even though the 489 * magazine may wind up with space available after we block on 490 * the spinlock, we still cycle it through to avoid the non-optimal 491 * corner-case. 492 * 493 * Obtain the depot spinlock. 494 */ 495 depot = &oc->depot[myclusterid]; 496 spin_lock_wr(&depot->spin); 497 498 /* 499 * If an empty magazine is available in the depot, cycle it 500 * through and retry. 501 */ 502 if (!SLIST_EMPTY(&depot->emptymagazines)) { 503 KKASSERT(cpucache->previous_magazine->cleaning + 504 cpucache->loaded_magazine->cleaning == 0); 505 loadedmag = cpucache->previous_magazine; 506 cpucache->previous_magazine = cpucache->loaded_magazine; 507 cpucache->loaded_magazine = SLIST_FIRST(&depot->emptymagazines); 508 SLIST_REMOVE_HEAD(&depot->emptymagazines, nextmagazine); 509 510 /* 511 * Return loadedmag to the depot. Due to blocking it may 512 * not be entirely full and could even be empty. 513 */ 514 if (MAGAZINE_EMPTY(loadedmag)) { 515 SLIST_INSERT_HEAD(&depot->emptymagazines, 516 loadedmag, nextmagazine); 517 spin_unlock_wr(&depot->spin); 518 } else { 519 SLIST_INSERT_HEAD(&depot->fullmagazines, 520 loadedmag, nextmagazine); 521 spin_unlock_wr(&depot->spin); 522 if (depot->waiting) 523 wakeup(depot); 524 } 525 goto retry; 526 } 527 528 /* 529 * An empty mag is not available. This is a corner case which can 530 * occur due to cpus holding partially full magazines. Do not try 531 * to allocate a mag, just free the object. 532 */ 533 ++depot->unallocated_objects; 534 spin_unlock_wr(&depot->spin); 535 if (depot->waiting) 536 wakeup(depot); 537 crit_exit(); 538 oc->dtor(obj, oc->private); 539 oc->free(obj, oc->allocator_args); 540 } 541 542 /* 543 * The object is being put back into the cache, but the caller has 544 * indicated that the object is not in any shape to be reused and should 545 * be dtor'd immediately. 546 */ 547 void 548 objcache_dtor(struct objcache *oc, void *obj) 549 { 550 struct magazinedepot *depot; 551 552 depot = &oc->depot[myclusterid]; 553 spin_lock_wr(&depot->spin); 554 ++depot->unallocated_objects; 555 spin_unlock_wr(&depot->spin); 556 if (depot->waiting) 557 wakeup(depot); 558 oc->dtor(obj, oc->private); 559 oc->free(obj, oc->allocator_args); 560 } 561 562 /* 563 * Deallocate all objects in a magazine and free the magazine if requested. 564 * The magazine must already be disassociated from the depot. 565 * 566 * Must be called with a critical section held when called with a per-cpu 567 * magazine. The magazine may be indirectly modified during the loop. 568 * 569 * The number of objects freed is returned. 570 */ 571 static int 572 mag_purge(struct objcache *oc, struct magazine *mag, int freeit) 573 { 574 int count; 575 void *obj; 576 577 count = 0; 578 ++mag->cleaning; 579 while (mag->rounds) { 580 obj = mag->objects[--mag->rounds]; 581 oc->dtor(obj, oc->private); /* MAY BLOCK */ 582 oc->free(obj, oc->allocator_args); /* MAY BLOCK */ 583 ++count; 584 585 /* 586 * Cycle for interrupts 587 */ 588 if ((count & 15) == 0) { 589 crit_exit(); 590 crit_enter(); 591 } 592 } 593 --mag->cleaning; 594 if (freeit) 595 kfree(mag, M_OBJMAG); 596 return(count); 597 } 598 599 /* 600 * Disassociate zero or more magazines from a magazine list associated with 601 * the depot, update the depot, and move the magazines to a temporary 602 * list. 603 * 604 * The caller must check the depot for waiters and wake it up, typically 605 * after disposing of the magazines this function loads onto the temporary 606 * list. 607 */ 608 static void 609 maglist_disassociate(struct magazinedepot *depot, struct magazinelist *maglist, 610 struct magazinelist *tmplist, boolean_t purgeall) 611 { 612 struct magazine *mag; 613 614 while ((mag = SLIST_FIRST(maglist)) != NULL) { 615 SLIST_REMOVE_HEAD(maglist, nextmagazine); 616 SLIST_INSERT_HEAD(tmplist, mag, nextmagazine); 617 depot->unallocated_objects += mag->rounds; 618 } 619 } 620 621 /* 622 * Deallocate all magazines and their contents from the passed temporary 623 * list. The magazines have already been accounted for by their depots. 624 * 625 * The total number of rounds freed is returned. This number is typically 626 * only used to determine whether a wakeup on the depot is needed or not. 627 */ 628 static int 629 maglist_purge(struct objcache *oc, struct magazinelist *maglist) 630 { 631 struct magazine *mag; 632 int count = 0; 633 634 /* 635 * can't use SLIST_FOREACH because blocking releases the depot 636 * spinlock 637 */ 638 while ((mag = SLIST_FIRST(maglist)) != NULL) { 639 SLIST_REMOVE_HEAD(maglist, nextmagazine); 640 count += mag_purge(oc, mag, TRUE); 641 } 642 return(count); 643 } 644 645 /* 646 * De-allocates all magazines on the full and empty magazine lists. 647 * 648 * Because this routine is called with a spinlock held, the magazines 649 * can only be disassociated and moved to a temporary list, not freed. 650 * 651 * The caller is responsible for freeing the magazines. 652 */ 653 static void 654 depot_disassociate(struct magazinedepot *depot, struct magazinelist *tmplist) 655 { 656 maglist_disassociate(depot, &depot->fullmagazines, tmplist, TRUE); 657 maglist_disassociate(depot, &depot->emptymagazines, tmplist, TRUE); 658 } 659 660 #ifdef notneeded 661 void 662 objcache_reclaim(struct objcache *oc) 663 { 664 struct percpu_objcache *cache_percpu = &oc->cache_percpu[myclusterid]; 665 struct magazinedepot *depot = &oc->depot[myclusterid]; 666 struct magazinelist tmplist; 667 int count; 668 669 SLIST_INIT(&tmplist); 670 crit_enter(); 671 count = mag_purge(oc, cache_percpu->loaded_magazine, FALSE); 672 count += mag_purge(oc, cache_percpu->previous_magazine, FALSE); 673 crit_exit(); 674 675 spin_lock_wr(&depot->spin); 676 depot->unallocated_objects += count; 677 depot_disassociate(depot, &tmplist); 678 spin_unlock_wr(&depot->spin); 679 count += maglist_purge(oc, &tmplist); 680 if (count && depot->waiting) 681 wakeup(depot); 682 } 683 #endif 684 685 /* 686 * Try to free up some memory. Return as soon as some free memory is found. 687 * For each object cache on the reclaim list, first try the current per-cpu 688 * cache, then the full magazine depot. 689 */ 690 boolean_t 691 objcache_reclaimlist(struct objcache *oclist[], int nlist, int ocflags) 692 { 693 struct objcache *oc; 694 struct percpu_objcache *cpucache; 695 struct magazinedepot *depot; 696 struct magazinelist tmplist; 697 int i, count; 698 699 SLIST_INIT(&tmplist); 700 701 for (i = 0; i < nlist; i++) { 702 oc = oclist[i]; 703 cpucache = &oc->cache_percpu[mycpuid]; 704 depot = &oc->depot[myclusterid]; 705 706 crit_enter(); 707 count = mag_purge(oc, cpucache->loaded_magazine, FALSE); 708 if (count == 0) 709 count += mag_purge(oc, cpucache->previous_magazine, FALSE); 710 crit_exit(); 711 if (count > 0) { 712 spin_lock_wr(&depot->spin); 713 depot->unallocated_objects += count; 714 spin_unlock_wr(&depot->spin); 715 if (depot->waiting) 716 wakeup(depot); 717 return (TRUE); 718 } 719 spin_lock_wr(&depot->spin); 720 maglist_disassociate(depot, &depot->fullmagazines, 721 &tmplist, FALSE); 722 spin_unlock_wr(&depot->spin); 723 count = maglist_purge(oc, &tmplist); 724 if (count > 0) { 725 if (depot->waiting) 726 wakeup(depot); 727 return (TRUE); 728 } 729 } 730 return (FALSE); 731 } 732 733 /* 734 * Destroy an object cache. Must have no existing references. 735 */ 736 void 737 objcache_destroy(struct objcache *oc) 738 { 739 struct percpu_objcache *cache_percpu; 740 struct magazinedepot *depot; 741 int clusterid, cpuid; 742 struct magazinelist tmplist; 743 744 SLIST_INIT(&tmplist); 745 for (clusterid = 0; clusterid < MAXCLUSTERS; clusterid++) { 746 depot = &oc->depot[clusterid]; 747 spin_lock_wr(&depot->spin); 748 depot_disassociate(depot, &tmplist); 749 spin_unlock_wr(&depot->spin); 750 } 751 maglist_purge(oc, &tmplist); 752 753 for (cpuid = 0; cpuid < ncpus; cpuid++) { 754 cache_percpu = &oc->cache_percpu[cpuid]; 755 756 mag_purge(oc, cache_percpu->loaded_magazine, TRUE); 757 mag_purge(oc, cache_percpu->previous_magazine, TRUE); 758 cache_percpu->loaded_magazine = NULL; 759 cache_percpu->previous_magazine = NULL; 760 /* don't bother adjusting depot->unallocated_objects */ 761 } 762 763 kfree(oc->name, M_TEMP); 764 kfree(oc, M_OBJCACHE); 765 } 766 767 #if 0 768 /* 769 * Populate the per-cluster depot with elements from a linear block 770 * of memory. Must be called for individually for each cluster. 771 * Populated depots should not be destroyed. 772 */ 773 void 774 objcache_populate_linear(struct objcache *oc, void *base, int nelts, int size) 775 { 776 char *p = base; 777 char *end = (char *)base + (nelts * size); 778 struct magazinedepot *depot = &oc->depot[myclusterid]; 779 struct magazine *emptymag = mag_alloc(depot->magcapcity); 780 781 while (p < end) { 782 emptymag->objects[emptymag->rounds++] = p; 783 if (MAGAZINE_FULL(emptymag)) { 784 spin_lock_wr(&depot->spin); 785 SLIST_INSERT_HEAD(&depot->fullmagazines, emptymag, 786 nextmagazine); 787 depot->unallocated_objects += emptymag->rounds; 788 spin_unlock_wr(&depot->spin); 789 if (depot->waiting) 790 wakeup(depot); 791 emptymag = mag_alloc(depot->magcapacity); 792 } 793 p += size; 794 } 795 if (MAGAZINE_EMPTY(emptymag)) { 796 mag_purge(oc, emptymag, TRUE); 797 } else { 798 spin_lock_wr(&depot->spin); 799 SLIST_INSERT_HEAD(&depot->fullmagazines, emptymag, 800 nextmagazine); 801 depot->unallocated_objects += emptymag->rounds; 802 spin_unlock_wr(&depot->spin); 803 if (depot->waiting) 804 wakeup(depot); 805 emptymag = mag_alloc(depot->magcapacity); 806 } 807 } 808 #endif 809 810 #if 0 811 /* 812 * Check depot contention once a minute. 813 * 2 contested locks per second allowed. 814 */ 815 static int objcache_rebalance_period; 816 static const int objcache_contention_rate = 120; 817 static struct callout objcache_callout; 818 819 #define MAXMAGSIZE 512 820 821 /* 822 * Check depot contention and increase magazine size if necessary. 823 */ 824 static void 825 objcache_timer(void *dummy) 826 { 827 struct objcache *oc; 828 struct magazinedepot *depot; 829 struct magazinelist tmplist; 830 831 XXX we need to detect when an objcache is destroyed out from under 832 us XXX 833 834 SLIST_INIT(&tmplist); 835 836 spin_lock_wr(&objcachelist_spin); 837 SLIST_FOREACH(oc, &allobjcaches, oc_next) { 838 depot = &oc->depot[myclusterid]; 839 if (depot->magcapacity < MAXMAGSIZE) { 840 if (depot->contested > objcache_contention_rate) { 841 spin_lock_wr(&depot->spin); 842 depot_disassociate(depot, &tmplist); 843 depot->magcapacity *= 2; 844 spin_unlock_wr(&depot->spin); 845 kprintf("objcache_timer: increasing cache %s" 846 " magsize to %d, contested %d times\n", 847 oc->name, depot->magcapacity, 848 depot->contested); 849 } 850 depot->contested = 0; 851 } 852 spin_unlock_wr(&objcachelist_spin); 853 if (maglist_purge(oc, &tmplist) > 0 && depot->waiting) 854 wakeup(depot); 855 spin_lock_wr(&objcachelist_spin); 856 } 857 spin_unlock_wr(&objcachelist_spin); 858 859 callout_reset(&objcache_callout, objcache_rebalance_period, 860 objcache_timer, NULL); 861 } 862 863 #endif 864 865 static void 866 objcache_init(void) 867 { 868 spin_init(&objcachelist_spin); 869 #if 0 870 callout_init(&objcache_callout); 871 objcache_rebalance_period = 60 * hz; 872 callout_reset(&objcache_callout, objcache_rebalance_period, 873 objcache_timer, NULL); 874 #endif 875 } 876 SYSINIT(objcache, SI_SUB_CPU, SI_ORDER_ANY, objcache_init, 0); 877