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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
 
769 palkovsky 29
/*
785 jermar 30
 * The SLAB allocator is closely modelled after OpenSolaris SLAB allocator
769 palkovsky 31
 * http://www.usenix.org/events/usenix01/full_papers/bonwick/bonwick_html/
32
 *
33
 * with the following exceptions:
34
 *   - empty SLABS are deallocated immediately
35
 *     (in Linux they are kept in linked list, in Solaris ???)
36
 *   - empty magazines are deallocated when not needed
37
 *     (in Solaris they are held in linked list in slab cache)
38
 *
39
 *   Following features are not currently supported but would be easy to do:
40
 *   - cache coloring
41
 *   - dynamic magazine growing (different magazine sizes are already
42
 *     supported, but we would need to adjust allocating strategy)
43
 *
44
 * The SLAB allocator supports per-CPU caches ('magazines') to facilitate
45
 * good SMP scaling.
46
 *
47
 * When a new object is being allocated, it is first checked, if it is
48
 * available in CPU-bound magazine. If it is not found there, it is
49
 * allocated from CPU-shared SLAB - if partial full is found, it is used,
50
 * otherwise a new one is allocated.
51
 *
52
 * When an object is being deallocated, it is put to CPU-bound magazine.
53
 * If there is no such magazine, new one is allocated (if it fails,
54
 * the object is deallocated into SLAB). If the magazine is full, it is
55
 * put into cpu-shared list of magazines and new one is allocated.
56
 *
57
 * The CPU-bound magazine is actually a pair of magazine to avoid
58
 * thrashing when somebody is allocating/deallocating 1 item at the magazine
59
 * size boundary. LIFO order is enforced, which should avoid fragmentation
60
 * as much as possible.
61
 *  
62
 * Every cache contains list of full slabs and list of partialy full slabs.
63
 * Empty SLABS are immediately freed (thrashing will be avoided because
64
 * of magazines).
65
 *
66
 * The SLAB information structure is kept inside the data area, if possible.
67
 * The cache can be marked that it should not use magazines. This is used
68
 * only for SLAB related caches to avoid deadlocks and infinite recursion
69
 * (the SLAB allocator uses itself for allocating all it's control structures).
70
 *
71
 * The SLAB allocator allocates lot of space and does not free it. When
72
 * frame allocator fails to allocate the frame, it calls slab_reclaim().
73
 * It tries 'light reclaim' first, then brutal reclaim. The light reclaim
74
 * releases slabs from cpu-shared magazine-list, until at least 1 slab
75
 * is deallocated in each cache (this algorithm should probably change).
76
 * The brutal reclaim removes all cached objects, even from CPU-bound
77
 * magazines.
78
 *
775 palkovsky 79
 * TODO: For better CPU-scaling the magazine allocation strategy should
80
 * be extended. Currently, if the cache does not have magazine, it asks
81
 * for non-cpu cached magazine cache to provide one. It might be feasible
82
 * to add cpu-cached magazine cache (which would allocate it's magazines
83
 * from non-cpu-cached mag. cache). This would provide a nice per-cpu
84
 * buffer. The other possibility is to use the per-cache
85
 * 'empty-magazine-list', which decreases competing for 1 per-system
86
 * magazine cache.
87
 *
776 palkovsky 88
 * - it might be good to add granularity of locks even to slab level,
89
 *   we could then try_spinlock over all partial slabs and thus improve
90
 *   scalability even on slab level
769 palkovsky 91
 */
92
 
93
 
759 palkovsky 94
#include <synch/spinlock.h>
95
#include <mm/slab.h>
96
#include <list.h>
97
#include <memstr.h>
98
#include <align.h>
99
#include <mm/heap.h>
762 palkovsky 100
#include <mm/frame.h>
759 palkovsky 101
#include <config.h>
102
#include <print.h>
103
#include <arch.h>
104
#include <panic.h>
762 palkovsky 105
#include <debug.h>
771 palkovsky 106
#include <bitops.h>
759 palkovsky 107
 
108
SPINLOCK_INITIALIZE(slab_cache_lock);
769 palkovsky 109
static LIST_INITIALIZE(slab_cache_list);
759 palkovsky 110
 
769 palkovsky 111
/** Magazine cache */
112
static slab_cache_t mag_cache;
113
/** Cache for cache descriptors */
114
static slab_cache_t slab_cache_cache;
759 palkovsky 115
 
769 palkovsky 116
/** Cache for external slab descriptors
117
 * This time we want per-cpu cache, so do not make it static
118
 * - using SLAB for internal SLAB structures will not deadlock,
119
 *   as all slab structures are 'small' - control structures of
120
 *   their caches do not require further allocation
121
 */
122
static slab_cache_t *slab_extern_cache;
771 palkovsky 123
/** Caches for malloc */
124
static slab_cache_t *malloc_caches[SLAB_MAX_MALLOC_W-SLAB_MIN_MALLOC_W+1];
125
char *malloc_names[] =  {
126
    "malloc-8","malloc-16","malloc-32","malloc-64","malloc-128",
127
    "malloc-256","malloc-512","malloc-1K","malloc-2K",
128
    "malloc-4K","malloc-8K","malloc-16K","malloc-32K",
129
    "malloc-64K","malloc-128K"
130
};
762 palkovsky 131
 
769 palkovsky 132
/** Slab descriptor */
762 palkovsky 133
typedef struct {
134
    slab_cache_t *cache; /**< Pointer to parent cache */
135
    link_t link;       /* List of full/partial slabs */
136
    void *start;       /**< Start address of first available item */
137
    count_t available; /**< Count of available items in this slab */
138
    index_t nextavail; /**< The index of next available item */
139
}slab_t;
140
 
759 palkovsky 141
/**************************************/
762 palkovsky 142
/* SLAB allocation functions          */
759 palkovsky 143
 
762 palkovsky 144
/**
145
 * Allocate frames for slab space and initialize
146
 *
147
 */
148
static slab_t * slab_space_alloc(slab_cache_t *cache, int flags)
149
{
150
    void *data;
151
    slab_t *slab;
152
    size_t fsize;
153
    int i;
154
    zone_t *zone = NULL;
155
    int status;
764 palkovsky 156
    frame_t *frame;
759 palkovsky 157
 
786 bondari 158
    data = (void *)frame_alloc_rc_zone(cache->order, FRAME_KA | flags, &status, &zone);
764 palkovsky 159
    if (status != FRAME_OK) {
762 palkovsky 160
        return NULL;
764 palkovsky 161
    }
768 palkovsky 162
    if (! (cache->flags & SLAB_CACHE_SLINSIDE)) {
769 palkovsky 163
        slab = slab_alloc(slab_extern_cache, flags);
762 palkovsky 164
        if (!slab) {
165
            frame_free((__address)data);
166
            return NULL;
167
        }
168
    } else {
169
        fsize = (PAGE_SIZE << cache->order);
170
        slab = data + fsize - sizeof(*slab);
171
    }
764 palkovsky 172
 
762 palkovsky 173
    /* Fill in slab structures */
763 jermar 174
    /* TODO: some better way of accessing the frame */
766 palkovsky 175
    for (i=0; i < (1 << cache->order); i++) {
764 palkovsky 176
        frame = ADDR2FRAME(zone, KA2PA((__address)(data+i*PAGE_SIZE)));
177
        frame->parent = slab;
762 palkovsky 178
    }
179
 
180
    slab->start = data;
181
    slab->available = cache->objects;
182
    slab->nextavail = 0;
767 palkovsky 183
    slab->cache = cache;
762 palkovsky 184
 
185
    for (i=0; i<cache->objects;i++)
186
        *((int *) (slab->start + i*cache->size)) = i+1;
764 palkovsky 187
 
188
    atomic_inc(&cache->allocated_slabs);
762 palkovsky 189
    return slab;
190
}
191
 
759 palkovsky 192
/**
766 palkovsky 193
 * Deallocate space associated with SLAB
762 palkovsky 194
 *
195
 * @return number of freed frames
196
 */
197
static count_t slab_space_free(slab_cache_t *cache, slab_t *slab)
198
{
199
    frame_free((__address)slab->start);
768 palkovsky 200
    if (! (cache->flags & SLAB_CACHE_SLINSIDE))
769 palkovsky 201
        slab_free(slab_extern_cache, slab);
764 palkovsky 202
 
203
    atomic_dec(&cache->allocated_slabs);
204
 
762 palkovsky 205
    return 1 << cache->order;
206
}
207
 
208
/** Map object to slab structure */
209
static slab_t * obj2slab(void *obj)
210
{
211
    frame_t *frame;
212
 
213
    frame = frame_addr2frame((__address)obj);
214
    return (slab_t *)frame->parent;
215
}
216
 
217
/**************************************/
218
/* SLAB functions */
219
 
220
 
221
/**
759 palkovsky 222
 * Return object to slab and call a destructor
223
 *
762 palkovsky 224
 * @param slab If the caller knows directly slab of the object, otherwise NULL
225
 *
759 palkovsky 226
 * @return Number of freed pages
227
 */
762 palkovsky 228
static count_t slab_obj_destroy(slab_cache_t *cache, void *obj,
229
                slab_t *slab)
759 palkovsky 230
{
787 palkovsky 231
    int freed = 0;
232
 
762 palkovsky 233
    if (!slab)
234
        slab = obj2slab(obj);
235
 
767 palkovsky 236
    ASSERT(slab->cache == cache);
780 palkovsky 237
    ASSERT(slab->available < cache->objects);
767 palkovsky 238
 
787 palkovsky 239
    if (cache->destructor)
240
        freed = cache->destructor(obj);
241
 
776 palkovsky 242
    spinlock_lock(&cache->slablock);
243
 
762 palkovsky 244
    *((int *)obj) = slab->nextavail;
245
    slab->nextavail = (obj - slab->start)/cache->size;
246
    slab->available++;
247
 
248
    /* Move it to correct list */
249
    if (slab->available == cache->objects) {
250
        /* Free associated memory */
251
        list_remove(&slab->link);
782 palkovsky 252
        spinlock_unlock(&cache->slablock);
253
 
787 palkovsky 254
        return freed + slab_space_free(cache, slab);
782 palkovsky 255
 
780 palkovsky 256
    } else if (slab->available == 1) {
257
        /* It was in full, move to partial */
258
        list_remove(&slab->link);
259
        list_prepend(&slab->link, &cache->partial_slabs);
762 palkovsky 260
    }
783 palkovsky 261
    spinlock_unlock(&cache->slablock);
787 palkovsky 262
    return freed;
759 palkovsky 263
}
264
 
265
/**
266
 * Take new object from slab or create new if needed
267
 *
268
 * @return Object address or null
269
 */
270
static void * slab_obj_create(slab_cache_t *cache, int flags)
271
{
762 palkovsky 272
    slab_t *slab;
273
    void *obj;
274
 
776 palkovsky 275
    spinlock_lock(&cache->slablock);
276
 
762 palkovsky 277
    if (list_empty(&cache->partial_slabs)) {
278
        /* Allow recursion and reclaiming
279
         * - this should work, as the SLAB control structures
280
         *   are small and do not need to allocte with anything
281
         *   other ten frame_alloc when they are allocating,
282
         *   that's why we should get recursion at most 1-level deep
283
         */
776 palkovsky 284
        spinlock_unlock(&cache->slablock);
762 palkovsky 285
        slab = slab_space_alloc(cache, flags);
780 palkovsky 286
        if (!slab)
287
            return NULL;
776 palkovsky 288
        spinlock_lock(&cache->slablock);
762 palkovsky 289
    } else {
290
        slab = list_get_instance(cache->partial_slabs.next,
291
                     slab_t,
292
                     link);
293
        list_remove(&slab->link);
294
    }
295
    obj = slab->start + slab->nextavail * cache->size;
296
    slab->nextavail = *((int *)obj);
297
    slab->available--;
787 palkovsky 298
 
762 palkovsky 299
    if (! slab->available)
764 palkovsky 300
        list_prepend(&slab->link, &cache->full_slabs);
762 palkovsky 301
    else
764 palkovsky 302
        list_prepend(&slab->link, &cache->partial_slabs);
776 palkovsky 303
 
304
    spinlock_unlock(&cache->slablock);
787 palkovsky 305
 
306
    if (cache->constructor && cache->constructor(obj, flags)) {
307
        /* Bad, bad, construction failed */
308
        slab_obj_destroy(cache, obj, slab);
309
        return NULL;
310
    }
762 palkovsky 311
    return obj;
759 palkovsky 312
}
313
 
314
/**************************************/
315
/* CPU-Cache slab functions */
316
 
317
/**
781 palkovsky 318
 * Finds a full magazine in cache, takes it from list
319
 * and returns it
320
 *
321
 * @param first If true, return first, else last mag
322
 */
323
static slab_magazine_t * get_mag_from_cache(slab_cache_t *cache,
324
                        int first)
325
{
326
    slab_magazine_t *mag = NULL;
327
    link_t *cur;
328
 
329
    spinlock_lock(&cache->maglock);
330
    if (!list_empty(&cache->magazines)) {
331
        if (first)
332
            cur = cache->magazines.next;
333
        else
334
            cur = cache->magazines.prev;
335
        mag = list_get_instance(cur, slab_magazine_t, link);
336
        list_remove(&mag->link);
337
        atomic_dec(&cache->magazine_counter);
338
    }
339
    spinlock_unlock(&cache->maglock);
340
    return mag;
341
}
342
 
343
/** Prepend magazine to magazine list in cache */
344
static void put_mag_to_cache(slab_cache_t *cache, slab_magazine_t *mag)
345
{
346
    spinlock_lock(&cache->maglock);
347
 
348
    list_prepend(&mag->link, &cache->magazines);
349
    atomic_inc(&cache->magazine_counter);
350
 
351
    spinlock_unlock(&cache->maglock);
352
}
353
 
354
/**
759 palkovsky 355
 * Free all objects in magazine and free memory associated with magazine
356
 *
357
 * @return Number of freed pages
358
 */
359
static count_t magazine_destroy(slab_cache_t *cache,
360
                slab_magazine_t *mag)
361
{
362
    int i;
363
    count_t frames = 0;
364
 
767 palkovsky 365
    for (i=0;i < mag->busy; i++) {
762 palkovsky 366
        frames += slab_obj_destroy(cache, mag->objs[i], NULL);
767 palkovsky 367
        atomic_dec(&cache->cached_objs);
368
    }
759 palkovsky 369
 
370
    slab_free(&mag_cache, mag);
371
 
372
    return frames;
373
}
374
 
375
/**
769 palkovsky 376
 * Find full magazine, set it as current and return it
377
 *
378
 * Assume cpu_magazine lock is held
379
 */
380
static slab_magazine_t * get_full_current_mag(slab_cache_t *cache)
381
{
382
    slab_magazine_t *cmag, *lastmag, *newmag;
383
 
384
    cmag = cache->mag_cache[CPU->id].current;
385
    lastmag = cache->mag_cache[CPU->id].last;
386
    if (cmag) { /* First try local CPU magazines */
387
        if (cmag->busy)
388
            return cmag;
389
 
390
        if (lastmag && lastmag->busy) {
391
            cache->mag_cache[CPU->id].current = lastmag;
392
            cache->mag_cache[CPU->id].last = cmag;
393
            return lastmag;
394
        }
395
    }
396
    /* Local magazines are empty, import one from magazine list */
781 palkovsky 397
    newmag = get_mag_from_cache(cache, 1);
398
    if (!newmag)
769 palkovsky 399
        return NULL;
400
 
401
    if (lastmag)
781 palkovsky 402
        magazine_destroy(cache, lastmag);
403
 
769 palkovsky 404
    cache->mag_cache[CPU->id].last = cmag;
405
    cache->mag_cache[CPU->id].current = newmag;
406
    return newmag;
407
}
408
 
409
/**
759 palkovsky 410
 * Try to find object in CPU-cache magazines
411
 *
412
 * @return Pointer to object or NULL if not available
413
 */
414
static void * magazine_obj_get(slab_cache_t *cache)
415
{
416
    slab_magazine_t *mag;
767 palkovsky 417
    void *obj;
759 palkovsky 418
 
772 palkovsky 419
    if (!CPU)
420
        return NULL;
421
 
759 palkovsky 422
    spinlock_lock(&cache->mag_cache[CPU->id].lock);
423
 
769 palkovsky 424
    mag = get_full_current_mag(cache);
425
    if (!mag) {
426
        spinlock_unlock(&cache->mag_cache[CPU->id].lock);
427
        return NULL;
759 palkovsky 428
    }
767 palkovsky 429
    obj = mag->objs[--mag->busy];
759 palkovsky 430
    spinlock_unlock(&cache->mag_cache[CPU->id].lock);
767 palkovsky 431
    atomic_dec(&cache->cached_objs);
432
 
433
    return obj;
759 palkovsky 434
}
435
 
436
/**
768 palkovsky 437
 * Assure that the current magazine is empty, return pointer to it, or NULL if
769 palkovsky 438
 * no empty magazine is available and cannot be allocated
759 palkovsky 439
 *
773 palkovsky 440
 * Assume mag_cache[CPU->id].lock is held
441
 *
759 palkovsky 442
 * We have 2 magazines bound to processor.
443
 * First try the current.
444
 *  If full, try the last.
445
 *   If full, put to magazines list.
446
 *   allocate new, exchange last & current
447
 *
768 palkovsky 448
 */
449
static slab_magazine_t * make_empty_current_mag(slab_cache_t *cache)
450
{
451
    slab_magazine_t *cmag,*lastmag,*newmag;
452
 
453
    cmag = cache->mag_cache[CPU->id].current;
454
    lastmag = cache->mag_cache[CPU->id].last;
455
 
456
    if (cmag) {
457
        if (cmag->busy < cmag->size)
458
            return cmag;
459
        if (lastmag && lastmag->busy < lastmag->size) {
460
            cache->mag_cache[CPU->id].last = cmag;
461
            cache->mag_cache[CPU->id].current = lastmag;
462
            return lastmag;
463
        }
464
    }
465
    /* current | last are full | nonexistent, allocate new */
466
    /* We do not want to sleep just because of caching */
467
    /* Especially we do not want reclaiming to start, as
468
     * this would deadlock */
469
    newmag = slab_alloc(&mag_cache, FRAME_ATOMIC | FRAME_NO_RECLAIM);
470
    if (!newmag)
471
        return NULL;
472
    newmag->size = SLAB_MAG_SIZE;
473
    newmag->busy = 0;
474
 
475
    /* Flush last to magazine list */
781 palkovsky 476
    if (lastmag)
477
        put_mag_to_cache(cache, lastmag);
478
 
768 palkovsky 479
    /* Move current as last, save new as current */
480
    cache->mag_cache[CPU->id].last = cmag; 
481
    cache->mag_cache[CPU->id].current = newmag;
482
 
483
    return newmag;
484
}
485
 
486
/**
487
 * Put object into CPU-cache magazine
488
 *
759 palkovsky 489
 * @return 0 - success, -1 - could not get memory
490
 */
491
static int magazine_obj_put(slab_cache_t *cache, void *obj)
492
{
493
    slab_magazine_t *mag;
494
 
772 palkovsky 495
    if (!CPU)
496
        return -1;
497
 
759 palkovsky 498
    spinlock_lock(&cache->mag_cache[CPU->id].lock);
768 palkovsky 499
 
500
    mag = make_empty_current_mag(cache);
769 palkovsky 501
    if (!mag) {
502
        spinlock_unlock(&cache->mag_cache[CPU->id].lock);
503
        return -1;
504
    }
759 palkovsky 505
 
506
    mag->objs[mag->busy++] = obj;
507
 
508
    spinlock_unlock(&cache->mag_cache[CPU->id].lock);
767 palkovsky 509
    atomic_inc(&cache->cached_objs);
759 palkovsky 510
    return 0;
511
}
512
 
513
 
514
/**************************************/
762 palkovsky 515
/* SLAB CACHE functions */
759 palkovsky 516
 
762 palkovsky 517
/** Return number of objects that fit in certain cache size */
518
static int comp_objects(slab_cache_t *cache)
519
{
520
    if (cache->flags & SLAB_CACHE_SLINSIDE)
521
        return ((PAGE_SIZE << cache->order) - sizeof(slab_t)) / cache->size;
522
    else
523
        return (PAGE_SIZE << cache->order) / cache->size;
524
}
525
 
526
/** Return wasted space in slab */
527
static int badness(slab_cache_t *cache)
528
{
529
    int objects;
530
    int ssize;
531
 
532
    objects = comp_objects(cache);
533
    ssize = PAGE_SIZE << cache->order;
534
    if (cache->flags & SLAB_CACHE_SLINSIDE)
535
        ssize -= sizeof(slab_t);
536
    return ssize - objects*cache->size;
537
}
538
 
759 palkovsky 539
/** Initialize allocated memory as a slab cache */
540
static void
541
_slab_cache_create(slab_cache_t *cache,
542
           char *name,
543
           size_t size,
544
           size_t align,
545
           int (*constructor)(void *obj, int kmflag),
787 palkovsky 546
           int (*destructor)(void *obj),
759 palkovsky 547
           int flags)
548
{
549
    int i;
771 palkovsky 550
    int pages;
783 palkovsky 551
    ipl_t ipl;
759 palkovsky 552
 
553
    memsetb((__address)cache, sizeof(*cache), 0);
554
    cache->name = name;
555
 
766 palkovsky 556
    if (align < sizeof(__native))
557
        align = sizeof(__native);
558
    size = ALIGN_UP(size, align);
559
 
762 palkovsky 560
    cache->size = size;
759 palkovsky 561
 
562
    cache->constructor = constructor;
563
    cache->destructor = destructor;
564
    cache->flags = flags;
565
 
566
    list_initialize(&cache->full_slabs);
567
    list_initialize(&cache->partial_slabs);
568
    list_initialize(&cache->magazines);
776 palkovsky 569
    spinlock_initialize(&cache->slablock, "slab_lock");
570
    spinlock_initialize(&cache->maglock, "slab_maglock");
768 palkovsky 571
    if (! (cache->flags & SLAB_CACHE_NOMAGAZINE)) {
773 palkovsky 572
        for (i=0; i < config.cpu_count; i++) {
772 palkovsky 573
            memsetb((__address)&cache->mag_cache[i],
574
                sizeof(cache->mag_cache[i]), 0);
759 palkovsky 575
            spinlock_initialize(&cache->mag_cache[i].lock,
776 palkovsky 576
                        "slab_maglock_cpu");
772 palkovsky 577
        }
759 palkovsky 578
    }
579
 
580
    /* Compute slab sizes, object counts in slabs etc. */
581
    if (cache->size < SLAB_INSIDE_SIZE)
582
        cache->flags |= SLAB_CACHE_SLINSIDE;
583
 
762 palkovsky 584
    /* Minimum slab order */
771 palkovsky 585
    pages = ((cache->size-1) >> PAGE_WIDTH) + 1;
586
    cache->order = fnzb(pages);
766 palkovsky 587
 
762 palkovsky 588
    while (badness(cache) > SLAB_MAX_BADNESS(cache)) {
589
        cache->order += 1;
590
    }
591
    cache->objects = comp_objects(cache);
766 palkovsky 592
    /* If info fits in, put it inside */
593
    if (badness(cache) > sizeof(slab_t))
594
        cache->flags |= SLAB_CACHE_SLINSIDE;
762 palkovsky 595
 
783 palkovsky 596
    /* Add cache to cache list */
597
    ipl = interrupts_disable();
759 palkovsky 598
    spinlock_lock(&slab_cache_lock);
599
 
600
    list_append(&cache->link, &slab_cache_list);
601
 
602
    spinlock_unlock(&slab_cache_lock);
783 palkovsky 603
    interrupts_restore(ipl);
759 palkovsky 604
}
605
 
606
/** Create slab cache  */
607
slab_cache_t * slab_cache_create(char *name,
608
                 size_t size,
609
                 size_t align,
610
                 int (*constructor)(void *obj, int kmflag),
787 palkovsky 611
                 int (*destructor)(void *obj),
759 palkovsky 612
                 int flags)
613
{
614
    slab_cache_t *cache;
615
 
769 palkovsky 616
    cache = slab_alloc(&slab_cache_cache, 0);
759 palkovsky 617
    _slab_cache_create(cache, name, size, align, constructor, destructor,
618
               flags);
619
    return cache;
620
}
621
 
622
/**
623
 * Reclaim space occupied by objects that are already free
624
 *
625
 * @param flags If contains SLAB_RECLAIM_ALL, do aggressive freeing
626
 * @return Number of freed pages
627
 */
628
static count_t _slab_reclaim(slab_cache_t *cache, int flags)
629
{
630
    int i;
631
    slab_magazine_t *mag;
632
    count_t frames = 0;
781 palkovsky 633
    int magcount;
759 palkovsky 634
 
635
    if (cache->flags & SLAB_CACHE_NOMAGAZINE)
636
        return 0; /* Nothing to do */
781 palkovsky 637
 
638
    /* We count up to original magazine count to avoid
639
     * endless loop
640
     */
641
    magcount = atomic_get(&cache->magazine_counter);
642
    while (magcount-- && (mag=get_mag_from_cache(cache,0))) {
643
        frames += magazine_destroy(cache,mag);
644
        if (!(flags & SLAB_RECLAIM_ALL) && frames)
645
            break;
769 palkovsky 646
    }
759 palkovsky 647
 
648
    if (flags & SLAB_RECLAIM_ALL) {
781 palkovsky 649
        /* Free cpu-bound magazines */
759 palkovsky 650
        /* Destroy CPU magazines */
651
        for (i=0; i<config.cpu_count; i++) {
781 palkovsky 652
            spinlock_lock(&cache->mag_cache[i].lock);
653
 
759 palkovsky 654
            mag = cache->mag_cache[i].current;
655
            if (mag)
656
                frames += magazine_destroy(cache, mag);
657
            cache->mag_cache[i].current = NULL;
658
 
659
            mag = cache->mag_cache[i].last;
660
            if (mag)
661
                frames += magazine_destroy(cache, mag);
662
            cache->mag_cache[i].last = NULL;
781 palkovsky 663
 
664
            spinlock_unlock(&cache->mag_cache[i].lock);
759 palkovsky 665
        }
666
    }
767 palkovsky 667
 
759 palkovsky 668
    return frames;
669
}
670
 
671
/** Check that there are no slabs and remove cache from system  */
672
void slab_cache_destroy(slab_cache_t *cache)
673
{
781 palkovsky 674
    ipl_t ipl;
675
 
676
    /* First remove cache from link, so that we don't need
677
     * to disable interrupts later
678
     */
679
 
680
    ipl = interrupts_disable();
681
    spinlock_lock(&slab_cache_lock);
682
 
683
    list_remove(&cache->link);
684
 
685
    spinlock_unlock(&slab_cache_lock);
686
    interrupts_restore(ipl);
687
 
759 palkovsky 688
    /* Do not lock anything, we assume the software is correct and
689
     * does not touch the cache when it decides to destroy it */
690
 
691
    /* Destroy all magazines */
692
    _slab_reclaim(cache, SLAB_RECLAIM_ALL);
693
 
694
    /* All slabs must be empty */
695
    if (!list_empty(&cache->full_slabs) \
696
        || !list_empty(&cache->partial_slabs))
697
        panic("Destroying cache that is not empty.");
698
 
769 palkovsky 699
    slab_free(&slab_cache_cache, cache);
759 palkovsky 700
}
701
 
702
/** Allocate new object from cache - if no flags given, always returns
703
    memory */
704
void * slab_alloc(slab_cache_t *cache, int flags)
705
{
706
    ipl_t ipl;
707
    void *result = NULL;
773 palkovsky 708
 
759 palkovsky 709
    /* Disable interrupts to avoid deadlocks with interrupt handlers */
710
    ipl = interrupts_disable();
771 palkovsky 711
 
772 palkovsky 712
    if (!(cache->flags & SLAB_CACHE_NOMAGAZINE))
759 palkovsky 713
        result = magazine_obj_get(cache);
776 palkovsky 714
    if (!result)
759 palkovsky 715
        result = slab_obj_create(cache, flags);
716
 
769 palkovsky 717
    interrupts_restore(ipl);
718
 
764 palkovsky 719
    if (result)
720
        atomic_inc(&cache->allocated_objs);
721
 
759 palkovsky 722
    return result;
723
}
724
 
771 palkovsky 725
/** Return object to cache, use slab if known  */
726
static void _slab_free(slab_cache_t *cache, void *obj, slab_t *slab)
759 palkovsky 727
{
728
    ipl_t ipl;
729
 
730
    ipl = interrupts_disable();
731
 
762 palkovsky 732
    if ((cache->flags & SLAB_CACHE_NOMAGAZINE) \
733
        || magazine_obj_put(cache, obj)) {
776 palkovsky 734
 
771 palkovsky 735
        slab_obj_destroy(cache, obj, slab);
776 palkovsky 736
 
759 palkovsky 737
    }
769 palkovsky 738
    interrupts_restore(ipl);
764 palkovsky 739
    atomic_dec(&cache->allocated_objs);
759 palkovsky 740
}
741
 
771 palkovsky 742
/** Return slab object to cache */
743
void slab_free(slab_cache_t *cache, void *obj)
744
{
745
    _slab_free(cache,obj,NULL);
746
}
747
 
759 palkovsky 748
/* Go through all caches and reclaim what is possible */
749
count_t slab_reclaim(int flags)
750
{
751
    slab_cache_t *cache;
752
    link_t *cur;
753
    count_t frames = 0;
754
 
755
    spinlock_lock(&slab_cache_lock);
756
 
776 palkovsky 757
    /* TODO: Add assert, that interrupts are disabled, otherwise
758
     * memory allocation from interrupts can deadlock.
759
     */
760
 
759 palkovsky 761
    for (cur = slab_cache_list.next;cur!=&slab_cache_list; cur=cur->next) {
762
        cache = list_get_instance(cur, slab_cache_t, link);
763
        frames += _slab_reclaim(cache, flags);
764
    }
765
 
766
    spinlock_unlock(&slab_cache_lock);
767
 
768
    return frames;
769
}
770
 
771
 
772
/* Print list of slabs */
773
void slab_print_list(void)
774
{
775
    slab_cache_t *cache;
776
    link_t *cur;
783 palkovsky 777
    ipl_t ipl;
778
 
779
    ipl = interrupts_disable();
759 palkovsky 780
    spinlock_lock(&slab_cache_lock);
767 palkovsky 781
    printf("SLAB name\tOsize\tPages\tObj/pg\tSlabs\tCached\tAllocobjs\tCtl\n");
759 palkovsky 782
    for (cur = slab_cache_list.next;cur!=&slab_cache_list; cur=cur->next) {
783
        cache = list_get_instance(cur, slab_cache_t, link);
767 palkovsky 784
        printf("%s\t%d\t%d\t%d\t%d\t%d\t%d\t\t%s\n", cache->name, cache->size,
766 palkovsky 785
               (1 << cache->order), cache->objects,
767 palkovsky 786
               atomic_get(&cache->allocated_slabs),
787
               atomic_get(&cache->cached_objs),
766 palkovsky 788
               atomic_get(&cache->allocated_objs),
789
               cache->flags & SLAB_CACHE_SLINSIDE ? "In" : "Out");
759 palkovsky 790
    }
791
    spinlock_unlock(&slab_cache_lock);
783 palkovsky 792
    interrupts_restore(ipl);
759 palkovsky 793
}
794
 
778 palkovsky 795
#ifdef CONFIG_DEBUG
796
static int _slab_initialized = 0;
797
#endif
798
 
759 palkovsky 799
void slab_cache_init(void)
800
{
771 palkovsky 801
    int i, size;
802
 
759 palkovsky 803
    /* Initialize magazine cache */
804
    _slab_cache_create(&mag_cache,
805
               "slab_magazine",
806
               sizeof(slab_magazine_t)+SLAB_MAG_SIZE*sizeof(void*),
807
               sizeof(__address),
808
               NULL, NULL,
769 palkovsky 809
               SLAB_CACHE_NOMAGAZINE | SLAB_CACHE_SLINSIDE);
810
    /* Initialize slab_cache cache */
811
    _slab_cache_create(&slab_cache_cache,
812
               "slab_cache",
813
               sizeof(slab_cache_cache) + config.cpu_count*sizeof(slab_cache_cache.mag_cache[0]),
814
               sizeof(__address),
815
               NULL, NULL,
816
               SLAB_CACHE_NOMAGAZINE | SLAB_CACHE_SLINSIDE);
817
    /* Initialize external slab cache */
818
    slab_extern_cache = slab_cache_create("slab_extern",
819
                          sizeof(slab_t),
820
                          0, NULL, NULL,
821
                          SLAB_CACHE_SLINSIDE);
759 palkovsky 822
 
823
    /* Initialize structures for malloc */
771 palkovsky 824
    for (i=0, size=(1<<SLAB_MIN_MALLOC_W);
825
         i < (SLAB_MAX_MALLOC_W-SLAB_MIN_MALLOC_W+1);
826
         i++, size <<= 1) {
827
        malloc_caches[i] = slab_cache_create(malloc_names[i],
828
                             size, 0,
829
                             NULL,NULL,0);
830
    }
778 palkovsky 831
#ifdef CONFIG_DEBUG       
832
    _slab_initialized = 1;
833
#endif
759 palkovsky 834
}
771 palkovsky 835
 
836
/**************************************/
837
/* kalloc/kfree functions             */
838
void * kalloc(unsigned int size, int flags)
839
{
840
    int idx;
778 palkovsky 841
 
842
    ASSERT(_slab_initialized);
771 palkovsky 843
    ASSERT( size && size <= (1 << SLAB_MAX_MALLOC_W));
844
 
845
    if (size < (1 << SLAB_MIN_MALLOC_W))
846
        size = (1 << SLAB_MIN_MALLOC_W);
847
 
848
    idx = fnzb(size-1) - SLAB_MIN_MALLOC_W + 1;
849
 
850
    return slab_alloc(malloc_caches[idx], flags);
851
}
852
 
853
 
854
void kfree(void *obj)
855
{
781 palkovsky 856
    slab_t *slab;
857
 
858
    if (!obj) return;
859
 
860
    slab = obj2slab(obj);
771 palkovsky 861
    _slab_free(slab->cache, obj, slab);
862
}