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759 palkovsky 1
/*
2
 * Copyright (C) 2006 Ondrej Palkovsky
3
 * 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
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
1702 cejka 29
 /** @addtogroup genericmm
30
 * @{
31
 */
32
 
1248 jermar 33
/**
1702 cejka 34
 * @file
1248 jermar 35
 * @brief   Slab allocator.
769 palkovsky 36
 *
1248 jermar 37
 * The slab allocator is closely modelled after OpenSolaris slab allocator.
38
 * @see http://www.usenix.org/events/usenix01/full_papers/bonwick/bonwick_html/
39
 *
769 palkovsky 40
 * with the following exceptions:
1248 jermar 41
 * @li empty slabs are deallocated immediately
769 palkovsky 42
 *     (in Linux they are kept in linked list, in Solaris ???)
1248 jermar 43
 * @li empty magazines are deallocated when not needed
769 palkovsky 44
 *     (in Solaris they are held in linked list in slab cache)
45
 *
1248 jermar 46
 * Following features are not currently supported but would be easy to do:
47
 * @li cache coloring
48
 * @li dynamic magazine growing (different magazine sizes are already
1144 jermar 49
 *     supported, but we would need to adjust allocation strategy)
769 palkovsky 50
 *
1248 jermar 51
 * The slab allocator supports per-CPU caches ('magazines') to facilitate
769 palkovsky 52
 * good SMP scaling.
53
 *
54
 * When a new object is being allocated, it is first checked, if it is
1554 jermar 55
 * available in a CPU-bound magazine. If it is not found there, it is
56
 * allocated from a CPU-shared slab - if a partially full one is found,
57
 * it is used, otherwise a new one is allocated.
769 palkovsky 58
 *
1554 jermar 59
 * When an object is being deallocated, it is put to a CPU-bound magazine.
60
 * If there is no such magazine, a new one is allocated (if this fails,
1248 jermar 61
 * the object is deallocated into slab). If the magazine is full, it is
1554 jermar 62
 * put into cpu-shared list of magazines and a new one is allocated.
769 palkovsky 63
 *
1554 jermar 64
 * The CPU-bound magazine is actually a pair of magazines in order to avoid
769 palkovsky 65
 * thrashing when somebody is allocating/deallocating 1 item at the magazine
66
 * size boundary. LIFO order is enforced, which should avoid fragmentation
67
 * as much as possible.
68
 *  
1554 jermar 69
 * Every cache contains list of full slabs and list of partially full slabs.
1248 jermar 70
 * Empty slabs are immediately freed (thrashing will be avoided because
769 palkovsky 71
 * of magazines).
72
 *
1248 jermar 73
 * The slab information structure is kept inside the data area, if possible.
769 palkovsky 74
 * The cache can be marked that it should not use magazines. This is used
1248 jermar 75
 * only for slab related caches to avoid deadlocks and infinite recursion
76
 * (the slab allocator uses itself for allocating all it's control structures).
769 palkovsky 77
 *
1554 jermar 78
 * The slab allocator allocates a lot of space and does not free it. When
79
 * the frame allocator fails to allocate a frame, it calls slab_reclaim().
769 palkovsky 80
 * It tries 'light reclaim' first, then brutal reclaim. The light reclaim
81
 * releases slabs from cpu-shared magazine-list, until at least 1 slab
82
 * is deallocated in each cache (this algorithm should probably change).
83
 * The brutal reclaim removes all cached objects, even from CPU-bound
84
 * magazines.
85
 *
1248 jermar 86
 * TODO:@n
87
 * For better CPU-scaling the magazine allocation strategy should
775 palkovsky 88
 * be extended. Currently, if the cache does not have magazine, it asks
89
 * for non-cpu cached magazine cache to provide one. It might be feasible
90
 * to add cpu-cached magazine cache (which would allocate it's magazines
91
 * from non-cpu-cached mag. cache). This would provide a nice per-cpu
92
 * buffer. The other possibility is to use the per-cache
93
 * 'empty-magazine-list', which decreases competing for 1 per-system
94
 * magazine cache.
95
 *
1248 jermar 96
 * @li it might be good to add granularity of locks even to slab level,
97
 *     we could then try_spinlock over all partial slabs and thus improve
98
 *     scalability even on slab level
769 palkovsky 99
 */
100
 
759 palkovsky 101
#include <synch/spinlock.h>
102
#include <mm/slab.h>
788 jermar 103
#include <adt/list.h>
759 palkovsky 104
#include <memstr.h>
105
#include <align.h>
762 palkovsky 106
#include <mm/frame.h>
759 palkovsky 107
#include <config.h>
108
#include <print.h>
109
#include <arch.h>
110
#include <panic.h>
762 palkovsky 111
#include <debug.h>
771 palkovsky 112
#include <bitops.h>
759 palkovsky 113
 
114
SPINLOCK_INITIALIZE(slab_cache_lock);
769 palkovsky 115
static LIST_INITIALIZE(slab_cache_list);
759 palkovsky 116
 
769 palkovsky 117
/** Magazine cache */
118
static slab_cache_t mag_cache;
119
/** Cache for cache descriptors */
120
static slab_cache_t slab_cache_cache;
121
/** Cache for external slab descriptors
122
 * This time we want per-cpu cache, so do not make it static
1248 jermar 123
 * - using slab for internal slab structures will not deadlock,
769 palkovsky 124
 *   as all slab structures are 'small' - control structures of
125
 *   their caches do not require further allocation
126
 */
127
static slab_cache_t *slab_extern_cache;
771 palkovsky 128
/** Caches for malloc */
129
static slab_cache_t *malloc_caches[SLAB_MAX_MALLOC_W-SLAB_MIN_MALLOC_W+1];
130
char *malloc_names[] =  {
791 palkovsky 131
    "malloc-16","malloc-32","malloc-64","malloc-128",
771 palkovsky 132
    "malloc-256","malloc-512","malloc-1K","malloc-2K",
133
    "malloc-4K","malloc-8K","malloc-16K","malloc-32K",
1428 palkovsky 134
    "malloc-64K","malloc-128K","malloc-256K"
771 palkovsky 135
};
762 palkovsky 136
 
769 palkovsky 137
/** Slab descriptor */
762 palkovsky 138
typedef struct {
139
    slab_cache_t *cache; /**< Pointer to parent cache */
140
    link_t link;       /* List of full/partial slabs */
141
    void *start;       /**< Start address of first available item */
142
    count_t available; /**< Count of available items in this slab */
143
    index_t nextavail; /**< The index of next available item */
144
}slab_t;
145
 
791 palkovsky 146
#ifdef CONFIG_DEBUG
147
static int _slab_initialized = 0;
148
#endif
149
 
759 palkovsky 150
/**************************************/
1248 jermar 151
/* Slab allocation functions          */
759 palkovsky 152
 
762 palkovsky 153
/**
154
 * Allocate frames for slab space and initialize
155
 *
156
 */
157
static slab_t * slab_space_alloc(slab_cache_t *cache, int flags)
158
{
159
    void *data;
160
    slab_t *slab;
161
    size_t fsize;
162
    int i;
163
    int status;
814 palkovsky 164
    pfn_t pfn;
165
    int zone=0;
166
 
167
    pfn = frame_alloc_rc_zone(cache->order, FRAME_KA | flags, &status, &zone);
168
    data = (void *) PA2KA(PFN2ADDR(pfn));
764 palkovsky 169
    if (status != FRAME_OK) {
762 palkovsky 170
        return NULL;
764 palkovsky 171
    }
768 palkovsky 172
    if (! (cache->flags & SLAB_CACHE_SLINSIDE)) {
769 palkovsky 173
        slab = slab_alloc(slab_extern_cache, flags);
762 palkovsky 174
        if (!slab) {
814 palkovsky 175
            frame_free(ADDR2PFN(KA2PA(data)));
762 palkovsky 176
            return NULL;
177
        }
178
    } else {
179
        fsize = (PAGE_SIZE << cache->order);
180
        slab = data + fsize - sizeof(*slab);
181
    }
1288 jermar 182
 
762 palkovsky 183
    /* Fill in slab structures */
814 palkovsky 184
    for (i=0; i < (1 << cache->order); i++)
185
        frame_set_parent(pfn+i, slab, zone);
762 palkovsky 186
 
187
    slab->start = data;
188
    slab->available = cache->objects;
189
    slab->nextavail = 0;
767 palkovsky 190
    slab->cache = cache;
762 palkovsky 191
 
192
    for (i=0; i<cache->objects;i++)
193
        *((int *) (slab->start + i*cache->size)) = i+1;
764 palkovsky 194
 
195
    atomic_inc(&cache->allocated_slabs);
762 palkovsky 196
    return slab;
197
}
198
 
759 palkovsky 199
/**
1248 jermar 200
 * Deallocate space associated with slab
762 palkovsky 201
 *
202
 * @return number of freed frames
203
 */
204
static count_t slab_space_free(slab_cache_t *cache, slab_t *slab)
205
{
814 palkovsky 206
    frame_free(ADDR2PFN(KA2PA(slab->start)));
768 palkovsky 207
    if (! (cache->flags & SLAB_CACHE_SLINSIDE))
769 palkovsky 208
        slab_free(slab_extern_cache, slab);
764 palkovsky 209
 
210
    atomic_dec(&cache->allocated_slabs);
211
 
762 palkovsky 212
    return 1 << cache->order;
213
}
214
 
215
/** Map object to slab structure */
216
static slab_t * obj2slab(void *obj)
217
{
814 palkovsky 218
    return (slab_t *)frame_get_parent(ADDR2PFN(KA2PA(obj)), 0);
762 palkovsky 219
}
220
 
221
/**************************************/
1248 jermar 222
/* Slab functions */
762 palkovsky 223
 
224
 
225
/**
759 palkovsky 226
 * Return object to slab and call a destructor
227
 *
762 palkovsky 228
 * @param slab If the caller knows directly slab of the object, otherwise NULL
229
 *
759 palkovsky 230
 * @return Number of freed pages
231
 */
762 palkovsky 232
static count_t slab_obj_destroy(slab_cache_t *cache, void *obj,
233
                slab_t *slab)
759 palkovsky 234
{
787 palkovsky 235
    int freed = 0;
236
 
762 palkovsky 237
    if (!slab)
238
        slab = obj2slab(obj);
239
 
767 palkovsky 240
    ASSERT(slab->cache == cache);
241
 
787 palkovsky 242
    if (cache->destructor)
243
        freed = cache->destructor(obj);
244
 
776 palkovsky 245
    spinlock_lock(&cache->slablock);
789 palkovsky 246
    ASSERT(slab->available < cache->objects);
776 palkovsky 247
 
762 palkovsky 248
    *((int *)obj) = slab->nextavail;
249
    slab->nextavail = (obj - slab->start)/cache->size;
250
    slab->available++;
251
 
252
    /* Move it to correct list */
253
    if (slab->available == cache->objects) {
254
        /* Free associated memory */
255
        list_remove(&slab->link);
782 palkovsky 256
        spinlock_unlock(&cache->slablock);
257
 
787 palkovsky 258
        return freed + slab_space_free(cache, slab);
782 palkovsky 259
 
780 palkovsky 260
    } else if (slab->available == 1) {
261
        /* It was in full, move to partial */
262
        list_remove(&slab->link);
263
        list_prepend(&slab->link, &cache->partial_slabs);
762 palkovsky 264
    }
783 palkovsky 265
    spinlock_unlock(&cache->slablock);
787 palkovsky 266
    return freed;
759 palkovsky 267
}
268
 
269
/**
270
 * Take new object from slab or create new if needed
271
 *
272
 * @return Object address or null
273
 */
274
static void * slab_obj_create(slab_cache_t *cache, int flags)
275
{
762 palkovsky 276
    slab_t *slab;
277
    void *obj;
278
 
776 palkovsky 279
    spinlock_lock(&cache->slablock);
280
 
762 palkovsky 281
    if (list_empty(&cache->partial_slabs)) {
282
        /* Allow recursion and reclaiming
1248 jermar 283
         * - this should work, as the slab control structures
1288 jermar 284
         *   are small and do not need to allocate with anything
285
         *   other than frame_alloc when they are allocating,
762 palkovsky 286
         *   that's why we should get recursion at most 1-level deep
287
         */
776 palkovsky 288
        spinlock_unlock(&cache->slablock);
762 palkovsky 289
        slab = slab_space_alloc(cache, flags);
780 palkovsky 290
        if (!slab)
291
            return NULL;
776 palkovsky 292
        spinlock_lock(&cache->slablock);
762 palkovsky 293
    } else {
294
        slab = list_get_instance(cache->partial_slabs.next,
295
                     slab_t,
296
                     link);
297
        list_remove(&slab->link);
298
    }
299
    obj = slab->start + slab->nextavail * cache->size;
300
    slab->nextavail = *((int *)obj);
301
    slab->available--;
787 palkovsky 302
 
762 palkovsky 303
    if (! slab->available)
764 palkovsky 304
        list_prepend(&slab->link, &cache->full_slabs);
762 palkovsky 305
    else
764 palkovsky 306
        list_prepend(&slab->link, &cache->partial_slabs);
776 palkovsky 307
 
308
    spinlock_unlock(&cache->slablock);
787 palkovsky 309
 
310
    if (cache->constructor && cache->constructor(obj, flags)) {
311
        /* Bad, bad, construction failed */
312
        slab_obj_destroy(cache, obj, slab);
313
        return NULL;
314
    }
762 palkovsky 315
    return obj;
759 palkovsky 316
}
317
 
318
/**************************************/
319
/* CPU-Cache slab functions */
320
 
321
/**
781 palkovsky 322
 * Finds a full magazine in cache, takes it from list
323
 * and returns it
324
 *
325
 * @param first If true, return first, else last mag
326
 */
327
static slab_magazine_t * get_mag_from_cache(slab_cache_t *cache,
328
                        int first)
329
{
330
    slab_magazine_t *mag = NULL;
331
    link_t *cur;
332
 
333
    spinlock_lock(&cache->maglock);
334
    if (!list_empty(&cache->magazines)) {
335
        if (first)
336
            cur = cache->magazines.next;
337
        else
338
            cur = cache->magazines.prev;
339
        mag = list_get_instance(cur, slab_magazine_t, link);
340
        list_remove(&mag->link);
341
        atomic_dec(&cache->magazine_counter);
342
    }
343
    spinlock_unlock(&cache->maglock);
344
    return mag;
345
}
346
 
347
/** Prepend magazine to magazine list in cache */
348
static void put_mag_to_cache(slab_cache_t *cache, slab_magazine_t *mag)
349
{
350
    spinlock_lock(&cache->maglock);
351
 
352
    list_prepend(&mag->link, &cache->magazines);
353
    atomic_inc(&cache->magazine_counter);
354
 
355
    spinlock_unlock(&cache->maglock);
356
}
357
 
358
/**
759 palkovsky 359
 * Free all objects in magazine and free memory associated with magazine
360
 *
361
 * @return Number of freed pages
362
 */
363
static count_t magazine_destroy(slab_cache_t *cache,
364
                slab_magazine_t *mag)
365
{
366
    int i;
367
    count_t frames = 0;
368
 
767 palkovsky 369
    for (i=0;i < mag->busy; i++) {
762 palkovsky 370
        frames += slab_obj_destroy(cache, mag->objs[i], NULL);
767 palkovsky 371
        atomic_dec(&cache->cached_objs);
372
    }
759 palkovsky 373
 
374
    slab_free(&mag_cache, mag);
375
 
376
    return frames;
377
}
378
 
379
/**
769 palkovsky 380
 * Find full magazine, set it as current and return it
381
 *
382
 * Assume cpu_magazine lock is held
383
 */
384
static slab_magazine_t * get_full_current_mag(slab_cache_t *cache)
385
{
386
    slab_magazine_t *cmag, *lastmag, *newmag;
387
 
388
    cmag = cache->mag_cache[CPU->id].current;
389
    lastmag = cache->mag_cache[CPU->id].last;
390
    if (cmag) { /* First try local CPU magazines */
391
        if (cmag->busy)
392
            return cmag;
393
 
394
        if (lastmag && lastmag->busy) {
395
            cache->mag_cache[CPU->id].current = lastmag;
396
            cache->mag_cache[CPU->id].last = cmag;
397
            return lastmag;
398
        }
399
    }
400
    /* Local magazines are empty, import one from magazine list */
781 palkovsky 401
    newmag = get_mag_from_cache(cache, 1);
402
    if (!newmag)
769 palkovsky 403
        return NULL;
404
 
405
    if (lastmag)
781 palkovsky 406
        magazine_destroy(cache, lastmag);
407
 
769 palkovsky 408
    cache->mag_cache[CPU->id].last = cmag;
409
    cache->mag_cache[CPU->id].current = newmag;
410
    return newmag;
411
}
412
 
413
/**
759 palkovsky 414
 * Try to find object in CPU-cache magazines
415
 *
416
 * @return Pointer to object or NULL if not available
417
 */
418
static void * magazine_obj_get(slab_cache_t *cache)
419
{
420
    slab_magazine_t *mag;
767 palkovsky 421
    void *obj;
759 palkovsky 422
 
772 palkovsky 423
    if (!CPU)
424
        return NULL;
425
 
759 palkovsky 426
    spinlock_lock(&cache->mag_cache[CPU->id].lock);
427
 
769 palkovsky 428
    mag = get_full_current_mag(cache);
429
    if (!mag) {
430
        spinlock_unlock(&cache->mag_cache[CPU->id].lock);
431
        return NULL;
759 palkovsky 432
    }
767 palkovsky 433
    obj = mag->objs[--mag->busy];
759 palkovsky 434
    spinlock_unlock(&cache->mag_cache[CPU->id].lock);
767 palkovsky 435
    atomic_dec(&cache->cached_objs);
436
 
437
    return obj;
759 palkovsky 438
}
439
 
440
/**
768 palkovsky 441
 * Assure that the current magazine is empty, return pointer to it, or NULL if
769 palkovsky 442
 * no empty magazine is available and cannot be allocated
759 palkovsky 443
 *
773 palkovsky 444
 * Assume mag_cache[CPU->id].lock is held
445
 *
759 palkovsky 446
 * We have 2 magazines bound to processor.
447
 * First try the current.
448
 *  If full, try the last.
449
 *   If full, put to magazines list.
450
 *   allocate new, exchange last & current
451
 *
768 palkovsky 452
 */
453
static slab_magazine_t * make_empty_current_mag(slab_cache_t *cache)
454
{
455
    slab_magazine_t *cmag,*lastmag,*newmag;
456
 
457
    cmag = cache->mag_cache[CPU->id].current;
458
    lastmag = cache->mag_cache[CPU->id].last;
459
 
460
    if (cmag) {
461
        if (cmag->busy < cmag->size)
462
            return cmag;
463
        if (lastmag && lastmag->busy < lastmag->size) {
464
            cache->mag_cache[CPU->id].last = cmag;
465
            cache->mag_cache[CPU->id].current = lastmag;
466
            return lastmag;
467
        }
468
    }
469
    /* current | last are full | nonexistent, allocate new */
470
    /* We do not want to sleep just because of caching */
471
    /* Especially we do not want reclaiming to start, as
472
     * this would deadlock */
473
    newmag = slab_alloc(&mag_cache, FRAME_ATOMIC | FRAME_NO_RECLAIM);
474
    if (!newmag)
475
        return NULL;
476
    newmag->size = SLAB_MAG_SIZE;
477
    newmag->busy = 0;
478
 
479
    /* Flush last to magazine list */
781 palkovsky 480
    if (lastmag)
481
        put_mag_to_cache(cache, lastmag);
482
 
768 palkovsky 483
    /* Move current as last, save new as current */
484
    cache->mag_cache[CPU->id].last = cmag; 
485
    cache->mag_cache[CPU->id].current = newmag;
486
 
487
    return newmag;
488
}
489
 
490
/**
491
 * Put object into CPU-cache magazine
492
 *
759 palkovsky 493
 * @return 0 - success, -1 - could not get memory
494
 */
495
static int magazine_obj_put(slab_cache_t *cache, void *obj)
496
{
497
    slab_magazine_t *mag;
498
 
772 palkovsky 499
    if (!CPU)
500
        return -1;
501
 
759 palkovsky 502
    spinlock_lock(&cache->mag_cache[CPU->id].lock);
768 palkovsky 503
 
504
    mag = make_empty_current_mag(cache);
769 palkovsky 505
    if (!mag) {
506
        spinlock_unlock(&cache->mag_cache[CPU->id].lock);
507
        return -1;
508
    }
759 palkovsky 509
 
510
    mag->objs[mag->busy++] = obj;
511
 
512
    spinlock_unlock(&cache->mag_cache[CPU->id].lock);
767 palkovsky 513
    atomic_inc(&cache->cached_objs);
759 palkovsky 514
    return 0;
515
}
516
 
517
 
518
/**************************************/
1248 jermar 519
/* Slab cache functions */
759 palkovsky 520
 
762 palkovsky 521
/** Return number of objects that fit in certain cache size */
522
static int comp_objects(slab_cache_t *cache)
523
{
524
    if (cache->flags & SLAB_CACHE_SLINSIDE)
525
        return ((PAGE_SIZE << cache->order) - sizeof(slab_t)) / cache->size;
526
    else
527
        return (PAGE_SIZE << cache->order) / cache->size;
528
}
529
 
530
/** Return wasted space in slab */
531
static int badness(slab_cache_t *cache)
532
{
533
    int objects;
534
    int ssize;
535
 
536
    objects = comp_objects(cache);
537
    ssize = PAGE_SIZE << cache->order;
538
    if (cache->flags & SLAB_CACHE_SLINSIDE)
539
        ssize -= sizeof(slab_t);
540
    return ssize - objects*cache->size;
541
}
542
 
789 palkovsky 543
/**
544
 * Initialize mag_cache structure in slab cache
545
 */
546
static void make_magcache(slab_cache_t *cache)
547
{
548
    int i;
791 palkovsky 549
 
550
    ASSERT(_slab_initialized >= 2);
789 palkovsky 551
 
822 palkovsky 552
    cache->mag_cache = malloc(sizeof(slab_mag_cache_t)*config.cpu_count,0);
789 palkovsky 553
    for (i=0; i < config.cpu_count; i++) {
554
        memsetb((__address)&cache->mag_cache[i],
555
            sizeof(cache->mag_cache[i]), 0);
556
        spinlock_initialize(&cache->mag_cache[i].lock,
557
                    "slab_maglock_cpu");
558
    }
559
}
560
 
759 palkovsky 561
/** Initialize allocated memory as a slab cache */
562
static void
563
_slab_cache_create(slab_cache_t *cache,
564
           char *name,
565
           size_t size,
566
           size_t align,
567
           int (*constructor)(void *obj, int kmflag),
787 palkovsky 568
           int (*destructor)(void *obj),
759 palkovsky 569
           int flags)
570
{
771 palkovsky 571
    int pages;
783 palkovsky 572
    ipl_t ipl;
759 palkovsky 573
 
574
    memsetb((__address)cache, sizeof(*cache), 0);
575
    cache->name = name;
576
 
766 palkovsky 577
    if (align < sizeof(__native))
578
        align = sizeof(__native);
579
    size = ALIGN_UP(size, align);
580
 
762 palkovsky 581
    cache->size = size;
759 palkovsky 582
 
583
    cache->constructor = constructor;
584
    cache->destructor = destructor;
585
    cache->flags = flags;
586
 
587
    list_initialize(&cache->full_slabs);
588
    list_initialize(&cache->partial_slabs);
589
    list_initialize(&cache->magazines);
776 palkovsky 590
    spinlock_initialize(&cache->slablock, "slab_lock");
591
    spinlock_initialize(&cache->maglock, "slab_maglock");
789 palkovsky 592
    if (! (cache->flags & SLAB_CACHE_NOMAGAZINE))
593
        make_magcache(cache);
759 palkovsky 594
 
595
    /* Compute slab sizes, object counts in slabs etc. */
596
    if (cache->size < SLAB_INSIDE_SIZE)
597
        cache->flags |= SLAB_CACHE_SLINSIDE;
598
 
762 palkovsky 599
    /* Minimum slab order */
1682 palkovsky 600
    pages = SIZE2FRAMES(cache->size);
1677 palkovsky 601
    /* We need the 2^order >= pages */
602
    if (pages == 1)
603
        cache->order = 0;
604
    else
605
        cache->order = fnzb(pages-1)+1;
766 palkovsky 606
 
762 palkovsky 607
    while (badness(cache) > SLAB_MAX_BADNESS(cache)) {
608
        cache->order += 1;
609
    }
610
    cache->objects = comp_objects(cache);
766 palkovsky 611
    /* If info fits in, put it inside */
612
    if (badness(cache) > sizeof(slab_t))
613
        cache->flags |= SLAB_CACHE_SLINSIDE;
762 palkovsky 614
 
783 palkovsky 615
    /* Add cache to cache list */
616
    ipl = interrupts_disable();
759 palkovsky 617
    spinlock_lock(&slab_cache_lock);
618
 
619
    list_append(&cache->link, &slab_cache_list);
620
 
621
    spinlock_unlock(&slab_cache_lock);
783 palkovsky 622
    interrupts_restore(ipl);
759 palkovsky 623
}
624
 
625
/** Create slab cache  */
626
slab_cache_t * slab_cache_create(char *name,
627
                 size_t size,
628
                 size_t align,
629
                 int (*constructor)(void *obj, int kmflag),
787 palkovsky 630
                 int (*destructor)(void *obj),
759 palkovsky 631
                 int flags)
632
{
633
    slab_cache_t *cache;
634
 
769 palkovsky 635
    cache = slab_alloc(&slab_cache_cache, 0);
759 palkovsky 636
    _slab_cache_create(cache, name, size, align, constructor, destructor,
637
               flags);
638
    return cache;
639
}
640
 
641
/**
642
 * Reclaim space occupied by objects that are already free
643
 *
644
 * @param flags If contains SLAB_RECLAIM_ALL, do aggressive freeing
645
 * @return Number of freed pages
646
 */
647
static count_t _slab_reclaim(slab_cache_t *cache, int flags)
648
{
649
    int i;
650
    slab_magazine_t *mag;
651
    count_t frames = 0;
781 palkovsky 652
    int magcount;
759 palkovsky 653
 
654
    if (cache->flags & SLAB_CACHE_NOMAGAZINE)
655
        return 0; /* Nothing to do */
781 palkovsky 656
 
657
    /* We count up to original magazine count to avoid
658
     * endless loop
659
     */
660
    magcount = atomic_get(&cache->magazine_counter);
661
    while (magcount-- && (mag=get_mag_from_cache(cache,0))) {
662
        frames += magazine_destroy(cache,mag);
663
        if (!(flags & SLAB_RECLAIM_ALL) && frames)
664
            break;
769 palkovsky 665
    }
759 palkovsky 666
 
667
    if (flags & SLAB_RECLAIM_ALL) {
781 palkovsky 668
        /* Free cpu-bound magazines */
759 palkovsky 669
        /* Destroy CPU magazines */
670
        for (i=0; i<config.cpu_count; i++) {
781 palkovsky 671
            spinlock_lock(&cache->mag_cache[i].lock);
672
 
759 palkovsky 673
            mag = cache->mag_cache[i].current;
674
            if (mag)
675
                frames += magazine_destroy(cache, mag);
676
            cache->mag_cache[i].current = NULL;
677
 
678
            mag = cache->mag_cache[i].last;
679
            if (mag)
680
                frames += magazine_destroy(cache, mag);
681
            cache->mag_cache[i].last = NULL;
781 palkovsky 682
 
683
            spinlock_unlock(&cache->mag_cache[i].lock);
759 palkovsky 684
        }
685
    }
767 palkovsky 686
 
759 palkovsky 687
    return frames;
688
}
689
 
690
/** Check that there are no slabs and remove cache from system  */
691
void slab_cache_destroy(slab_cache_t *cache)
692
{
781 palkovsky 693
    ipl_t ipl;
694
 
695
    /* First remove cache from link, so that we don't need
696
     * to disable interrupts later
697
     */
698
 
699
    ipl = interrupts_disable();
700
    spinlock_lock(&slab_cache_lock);
701
 
702
    list_remove(&cache->link);
703
 
704
    spinlock_unlock(&slab_cache_lock);
705
    interrupts_restore(ipl);
706
 
759 palkovsky 707
    /* Do not lock anything, we assume the software is correct and
708
     * does not touch the cache when it decides to destroy it */
709
 
710
    /* Destroy all magazines */
711
    _slab_reclaim(cache, SLAB_RECLAIM_ALL);
712
 
713
    /* All slabs must be empty */
714
    if (!list_empty(&cache->full_slabs) \
715
        || !list_empty(&cache->partial_slabs))
716
        panic("Destroying cache that is not empty.");
717
 
789 palkovsky 718
    if (!(cache->flags & SLAB_CACHE_NOMAGAZINE))
822 palkovsky 719
        free(cache->mag_cache);
769 palkovsky 720
    slab_free(&slab_cache_cache, cache);
759 palkovsky 721
}
722
 
723
/** Allocate new object from cache - if no flags given, always returns
724
    memory */
725
void * slab_alloc(slab_cache_t *cache, int flags)
726
{
727
    ipl_t ipl;
728
    void *result = NULL;
773 palkovsky 729
 
759 palkovsky 730
    /* Disable interrupts to avoid deadlocks with interrupt handlers */
731
    ipl = interrupts_disable();
771 palkovsky 732
 
814 palkovsky 733
    if (!(cache->flags & SLAB_CACHE_NOMAGAZINE)) {
759 palkovsky 734
        result = magazine_obj_get(cache);
814 palkovsky 735
    }
776 palkovsky 736
    if (!result)
759 palkovsky 737
        result = slab_obj_create(cache, flags);
738
 
769 palkovsky 739
    interrupts_restore(ipl);
740
 
764 palkovsky 741
    if (result)
742
        atomic_inc(&cache->allocated_objs);
743
 
759 palkovsky 744
    return result;
745
}
746
 
771 palkovsky 747
/** Return object to cache, use slab if known  */
748
static void _slab_free(slab_cache_t *cache, void *obj, slab_t *slab)
759 palkovsky 749
{
750
    ipl_t ipl;
751
 
752
    ipl = interrupts_disable();
753
 
762 palkovsky 754
    if ((cache->flags & SLAB_CACHE_NOMAGAZINE) \
755
        || magazine_obj_put(cache, obj)) {
776 palkovsky 756
 
771 palkovsky 757
        slab_obj_destroy(cache, obj, slab);
776 palkovsky 758
 
759 palkovsky 759
    }
769 palkovsky 760
    interrupts_restore(ipl);
764 palkovsky 761
    atomic_dec(&cache->allocated_objs);
759 palkovsky 762
}
763
 
771 palkovsky 764
/** Return slab object to cache */
765
void slab_free(slab_cache_t *cache, void *obj)
766
{
767
    _slab_free(cache,obj,NULL);
768
}
769
 
759 palkovsky 770
/* Go through all caches and reclaim what is possible */
771
count_t slab_reclaim(int flags)
772
{
773
    slab_cache_t *cache;
774
    link_t *cur;
775
    count_t frames = 0;
776
 
777
    spinlock_lock(&slab_cache_lock);
778
 
776 palkovsky 779
    /* TODO: Add assert, that interrupts are disabled, otherwise
780
     * memory allocation from interrupts can deadlock.
781
     */
782
 
759 palkovsky 783
    for (cur = slab_cache_list.next;cur!=&slab_cache_list; cur=cur->next) {
784
        cache = list_get_instance(cur, slab_cache_t, link);
785
        frames += _slab_reclaim(cache, flags);
786
    }
787
 
788
    spinlock_unlock(&slab_cache_lock);
789
 
790
    return frames;
791
}
792
 
793
 
794
/* Print list of slabs */
795
void slab_print_list(void)
796
{
797
    slab_cache_t *cache;
798
    link_t *cur;
783 palkovsky 799
    ipl_t ipl;
800
 
801
    ipl = interrupts_disable();
759 palkovsky 802
    spinlock_lock(&slab_cache_lock);
1248 jermar 803
    printf("slab name\t  Osize\t  Pages\t Obj/pg\t  Slabs\t Cached\tAllocobjs\tCtl\n");
759 palkovsky 804
    for (cur = slab_cache_list.next;cur!=&slab_cache_list; cur=cur->next) {
805
        cache = list_get_instance(cur, slab_cache_t, link);
1224 cejka 806
        printf("%s\t%7zd\t%7zd\t%7zd\t%7zd\t%7zd\t%7zd\t\t%s\n", cache->name, cache->size,
766 palkovsky 807
               (1 << cache->order), cache->objects,
767 palkovsky 808
               atomic_get(&cache->allocated_slabs),
809
               atomic_get(&cache->cached_objs),
766 palkovsky 810
               atomic_get(&cache->allocated_objs),
811
               cache->flags & SLAB_CACHE_SLINSIDE ? "In" : "Out");
759 palkovsky 812
    }
813
    spinlock_unlock(&slab_cache_lock);
783 palkovsky 814
    interrupts_restore(ipl);
759 palkovsky 815
}
816
 
817
void slab_cache_init(void)
818
{
771 palkovsky 819
    int i, size;
820
 
759 palkovsky 821
    /* Initialize magazine cache */
822
    _slab_cache_create(&mag_cache,
823
               "slab_magazine",
824
               sizeof(slab_magazine_t)+SLAB_MAG_SIZE*sizeof(void*),
825
               sizeof(__address),
826
               NULL, NULL,
769 palkovsky 827
               SLAB_CACHE_NOMAGAZINE | SLAB_CACHE_SLINSIDE);
828
    /* Initialize slab_cache cache */
829
    _slab_cache_create(&slab_cache_cache,
830
               "slab_cache",
789 palkovsky 831
               sizeof(slab_cache_cache),
769 palkovsky 832
               sizeof(__address),
833
               NULL, NULL,
834
               SLAB_CACHE_NOMAGAZINE | SLAB_CACHE_SLINSIDE);
835
    /* Initialize external slab cache */
836
    slab_extern_cache = slab_cache_create("slab_extern",
837
                          sizeof(slab_t),
838
                          0, NULL, NULL,
789 palkovsky 839
                          SLAB_CACHE_SLINSIDE | SLAB_CACHE_MAGDEFERRED);
759 palkovsky 840
 
841
    /* Initialize structures for malloc */
771 palkovsky 842
    for (i=0, size=(1<<SLAB_MIN_MALLOC_W);
843
         i < (SLAB_MAX_MALLOC_W-SLAB_MIN_MALLOC_W+1);
844
         i++, size <<= 1) {
845
        malloc_caches[i] = slab_cache_create(malloc_names[i],
846
                             size, 0,
789 palkovsky 847
                             NULL,NULL, SLAB_CACHE_MAGDEFERRED);
771 palkovsky 848
    }
778 palkovsky 849
#ifdef CONFIG_DEBUG       
850
    _slab_initialized = 1;
851
#endif
759 palkovsky 852
}
771 palkovsky 853
 
789 palkovsky 854
/** Enable cpu_cache
855
 *
856
 * Kernel calls this function, when it knows the real number of
857
 * processors.
858
 * Allocate slab for cpucache and enable it on all existing
859
 * slabs that are SLAB_CACHE_MAGDEFERRED
860
 */
861
void slab_enable_cpucache(void)
862
{
863
    link_t *cur;
864
    slab_cache_t *s;
865
 
791 palkovsky 866
#ifdef CONFIG_DEBUG
867
    _slab_initialized = 2;
868
#endif
869
 
789 palkovsky 870
    spinlock_lock(&slab_cache_lock);
871
 
872
    for (cur=slab_cache_list.next; cur != &slab_cache_list;cur=cur->next){
873
        s = list_get_instance(cur, slab_cache_t, link);
874
        if ((s->flags & SLAB_CACHE_MAGDEFERRED) != SLAB_CACHE_MAGDEFERRED)
875
            continue;
876
        make_magcache(s);
877
        s->flags &= ~SLAB_CACHE_MAGDEFERRED;
878
    }
879
 
880
    spinlock_unlock(&slab_cache_lock);
881
}
882
 
771 palkovsky 883
/**************************************/
884
/* kalloc/kfree functions             */
822 palkovsky 885
void * malloc(unsigned int size, int flags)
771 palkovsky 886
{
887
    int idx;
778 palkovsky 888
 
889
    ASSERT(_slab_initialized);
1288 jermar 890
    ASSERT(size && size <= (1 << SLAB_MAX_MALLOC_W));
771 palkovsky 891
 
892
    if (size < (1 << SLAB_MIN_MALLOC_W))
893
        size = (1 << SLAB_MIN_MALLOC_W);
894
 
895
    idx = fnzb(size-1) - SLAB_MIN_MALLOC_W + 1;
896
 
897
    return slab_alloc(malloc_caches[idx], flags);
898
}
899
 
822 palkovsky 900
void free(void *obj)
771 palkovsky 901
{
781 palkovsky 902
    slab_t *slab;
903
 
904
    if (!obj) return;
905
 
906
    slab = obj2slab(obj);
771 palkovsky 907
    _slab_free(slab->cache, obj, slab);
908
}
1702 cejka 909
 
910
 /** @}
911
 */
912