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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>
788 jermar 96
#include <adt/list.h>
759 palkovsky 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;
115
/** Cache for external slab descriptors
116
 * This time we want per-cpu cache, so do not make it static
117
 * - using SLAB for internal SLAB structures will not deadlock,
118
 *   as all slab structures are 'small' - control structures of
119
 *   their caches do not require further allocation
120
 */
121
static slab_cache_t *slab_extern_cache;
771 palkovsky 122
/** Caches for malloc */
123
static slab_cache_t *malloc_caches[SLAB_MAX_MALLOC_W-SLAB_MIN_MALLOC_W+1];
124
char *malloc_names[] =  {
791 palkovsky 125
	"malloc-16","malloc-32","malloc-64","malloc-128",
771 palkovsky 126
	"malloc-256","malloc-512","malloc-1K","malloc-2K",
127
	"malloc-4K","malloc-8K","malloc-16K","malloc-32K",
128
	"malloc-64K","malloc-128K"
129
};
762 palkovsky 130
 
769 palkovsky 131
/** Slab descriptor */
762 palkovsky 132
typedef struct {
133
	slab_cache_t *cache; /**< Pointer to parent cache */
134
	link_t link;       /* List of full/partial slabs */
135
	void *start;       /**< Start address of first available item */
136
	count_t available; /**< Count of available items in this slab */
137
	index_t nextavail; /**< The index of next available item */
138
}slab_t;
139
 
791 palkovsky 140
#ifdef CONFIG_DEBUG
141
static int _slab_initialized = 0;
142
#endif
143
 
759 palkovsky 144
/**************************************/
762 palkovsky 145
/* SLAB allocation functions          */
759 palkovsky 146
 
762 palkovsky 147
/**
148
 * Allocate frames for slab space and initialize
149
 *
150
 */
151
static slab_t * slab_space_alloc(slab_cache_t *cache, int flags)
152
{
153
	void *data;
154
	slab_t *slab;
155
	size_t fsize;
156
	int i;
157
	zone_t *zone = NULL;
158
	int status;
764 palkovsky 159
	frame_t *frame;
759 palkovsky 160
 
786 bondari 161
	data = (void *)frame_alloc_rc_zone(cache->order, FRAME_KA | flags, &status, &zone);
764 palkovsky 162
	if (status != FRAME_OK) {
762 palkovsky 163
		return NULL;
764 palkovsky 164
	}
768 palkovsky 165
	if (! (cache->flags & SLAB_CACHE_SLINSIDE)) {
769 palkovsky 166
		slab = slab_alloc(slab_extern_cache, flags);
762 palkovsky 167
		if (!slab) {
168
			frame_free((__address)data);
169
			return NULL;
170
		}
171
	} else {
172
		fsize = (PAGE_SIZE << cache->order);
173
		slab = data + fsize - sizeof(*slab);
174
	}
764 palkovsky 175
 
762 palkovsky 176
	/* Fill in slab structures */
763 jermar 177
	/* TODO: some better way of accessing the frame */
766 palkovsky 178
	for (i=0; i < (1 << cache->order); i++) {
764 palkovsky 179
		frame = ADDR2FRAME(zone, KA2PA((__address)(data+i*PAGE_SIZE)));
180
		frame->parent = slab;
762 palkovsky 181
	}
182
 
183
	slab->start = data;
184
	slab->available = cache->objects;
185
	slab->nextavail = 0;
767 palkovsky 186
	slab->cache = cache;
762 palkovsky 187
 
188
	for (i=0; i<cache->objects;i++)
189
		*((int *) (slab->start + i*cache->size)) = i+1;
764 palkovsky 190
 
191
	atomic_inc(&cache->allocated_slabs);
762 palkovsky 192
	return slab;
193
}
194
 
759 palkovsky 195
/**
766 palkovsky 196
 * Deallocate space associated with SLAB
762 palkovsky 197
 *
198
 * @return number of freed frames
199
 */
200
static count_t slab_space_free(slab_cache_t *cache, slab_t *slab)
201
{
202
	frame_free((__address)slab->start);
768 palkovsky 203
	if (! (cache->flags & SLAB_CACHE_SLINSIDE))
769 palkovsky 204
		slab_free(slab_extern_cache, slab);
764 palkovsky 205
 
206
	atomic_dec(&cache->allocated_slabs);
207
 
762 palkovsky 208
	return 1 << cache->order;
209
}
210
 
211
/** Map object to slab structure */
212
static slab_t * obj2slab(void *obj)
213
{
214
	frame_t *frame; 
215
 
216
	frame = frame_addr2frame((__address)obj);
217
	return (slab_t *)frame->parent;
218
}
219
 
220
/**************************************/
221
/* SLAB functions */
222
 
223
 
224
/**
759 palkovsky 225
 * Return object to slab and call a destructor
226
 *
762 palkovsky 227
 * @param slab If the caller knows directly slab of the object, otherwise NULL
228
 *
759 palkovsky 229
 * @return Number of freed pages
230
 */
762 palkovsky 231
static count_t slab_obj_destroy(slab_cache_t *cache, void *obj,
232
				slab_t *slab)
759 palkovsky 233
{
787 palkovsky 234
	int freed = 0;
235
 
762 palkovsky 236
	if (!slab)
237
		slab = obj2slab(obj);
238
 
767 palkovsky 239
	ASSERT(slab->cache == cache);
240
 
787 palkovsky 241
	if (cache->destructor)
242
		freed = cache->destructor(obj);
243
 
776 palkovsky 244
	spinlock_lock(&cache->slablock);
789 palkovsky 245
	ASSERT(slab->available < cache->objects);
776 palkovsky 246
 
762 palkovsky 247
	*((int *)obj) = slab->nextavail;
248
	slab->nextavail = (obj - slab->start)/cache->size;
249
	slab->available++;
250
 
251
	/* Move it to correct list */
252
	if (slab->available == cache->objects) {
253
		/* Free associated memory */
254
		list_remove(&slab->link);
782 palkovsky 255
		spinlock_unlock(&cache->slablock);
256
 
787 palkovsky 257
		return freed + slab_space_free(cache, slab);
782 palkovsky 258
 
780 palkovsky 259
	} else if (slab->available == 1) {
260
		/* It was in full, move to partial */
261
		list_remove(&slab->link);
262
		list_prepend(&slab->link, &cache->partial_slabs);
762 palkovsky 263
	}
783 palkovsky 264
	spinlock_unlock(&cache->slablock);
787 palkovsky 265
	return freed;
759 palkovsky 266
}
267
 
268
/**
269
 * Take new object from slab or create new if needed
270
 *
271
 * @return Object address or null
272
 */
273
static void * slab_obj_create(slab_cache_t *cache, int flags)
274
{
762 palkovsky 275
	slab_t *slab;
276
	void *obj;
277
 
776 palkovsky 278
	spinlock_lock(&cache->slablock);
279
 
762 palkovsky 280
	if (list_empty(&cache->partial_slabs)) {
281
		/* Allow recursion and reclaiming
282
		 * - this should work, as the SLAB control structures
283
		 *   are small and do not need to allocte with anything
284
		 *   other ten frame_alloc when they are allocating,
285
		 *   that's why we should get recursion at most 1-level deep
286
		 */
776 palkovsky 287
		spinlock_unlock(&cache->slablock);
762 palkovsky 288
		slab = slab_space_alloc(cache, flags);
780 palkovsky 289
		if (!slab)
290
			return NULL;
776 palkovsky 291
		spinlock_lock(&cache->slablock);
762 palkovsky 292
	} else {
293
		slab = list_get_instance(cache->partial_slabs.next,
294
					 slab_t,
295
					 link);
296
		list_remove(&slab->link);
297
	}
298
	obj = slab->start + slab->nextavail * cache->size;
299
	slab->nextavail = *((int *)obj);
300
	slab->available--;
787 palkovsky 301
 
762 palkovsky 302
	if (! slab->available)
764 palkovsky 303
		list_prepend(&slab->link, &cache->full_slabs);
762 palkovsky 304
	else
764 palkovsky 305
		list_prepend(&slab->link, &cache->partial_slabs);
776 palkovsky 306
 
307
	spinlock_unlock(&cache->slablock);
787 palkovsky 308
 
309
	if (cache->constructor && cache->constructor(obj, flags)) {
310
		/* Bad, bad, construction failed */
311
		slab_obj_destroy(cache, obj, slab);
312
		return NULL;
313
	}
762 palkovsky 314
	return obj;
759 palkovsky 315
}
316
 
317
/**************************************/
318
/* CPU-Cache slab functions */
319
 
320
/**
781 palkovsky 321
 * Finds a full magazine in cache, takes it from list
322
 * and returns it 
323
 *
324
 * @param first If true, return first, else last mag
325
 */
326
static slab_magazine_t * get_mag_from_cache(slab_cache_t *cache,
327
					    int first)
328
{
329
	slab_magazine_t *mag = NULL;
330
	link_t *cur;
331
 
332
	spinlock_lock(&cache->maglock);
333
	if (!list_empty(&cache->magazines)) {
334
		if (first)
335
			cur = cache->magazines.next;
336
		else
337
			cur = cache->magazines.prev;
338
		mag = list_get_instance(cur, slab_magazine_t, link);
339
		list_remove(&mag->link);
340
		atomic_dec(&cache->magazine_counter);
341
	}
342
	spinlock_unlock(&cache->maglock);
343
	return mag;
344
}
345
 
346
/** Prepend magazine to magazine list in cache */
347
static void put_mag_to_cache(slab_cache_t *cache, slab_magazine_t *mag)
348
{
349
	spinlock_lock(&cache->maglock);
350
 
351
	list_prepend(&mag->link, &cache->magazines);
352
	atomic_inc(&cache->magazine_counter);
353
 
354
	spinlock_unlock(&cache->maglock);
355
}
356
 
357
/**
759 palkovsky 358
 * Free all objects in magazine and free memory associated with magazine
359
 *
360
 * @return Number of freed pages
361
 */
362
static count_t magazine_destroy(slab_cache_t *cache, 
363
				slab_magazine_t *mag)
364
{
365
	int i;
366
	count_t frames = 0;
367
 
767 palkovsky 368
	for (i=0;i < mag->busy; i++) {
762 palkovsky 369
		frames += slab_obj_destroy(cache, mag->objs[i], NULL);
767 palkovsky 370
		atomic_dec(&cache->cached_objs);
371
	}
759 palkovsky 372
 
373
	slab_free(&mag_cache, mag);
374
 
375
	return frames;
376
}
377
 
378
/**
769 palkovsky 379
 * Find full magazine, set it as current and return it
380
 *
381
 * Assume cpu_magazine lock is held
382
 */
383
static slab_magazine_t * get_full_current_mag(slab_cache_t *cache)
384
{
385
	slab_magazine_t *cmag, *lastmag, *newmag;
386
 
387
	cmag = cache->mag_cache[CPU->id].current;
388
	lastmag = cache->mag_cache[CPU->id].last;
389
	if (cmag) { /* First try local CPU magazines */
390
		if (cmag->busy)
391
			return cmag;
392
 
393
		if (lastmag && lastmag->busy) {
394
			cache->mag_cache[CPU->id].current = lastmag;
395
			cache->mag_cache[CPU->id].last = cmag;
396
			return lastmag;
397
		}
398
	}
399
	/* Local magazines are empty, import one from magazine list */
781 palkovsky 400
	newmag = get_mag_from_cache(cache, 1);
401
	if (!newmag)
769 palkovsky 402
		return NULL;
403
 
404
	if (lastmag)
781 palkovsky 405
		magazine_destroy(cache, lastmag);
406
 
769 palkovsky 407
	cache->mag_cache[CPU->id].last = cmag;
408
	cache->mag_cache[CPU->id].current = newmag;
409
	return newmag;
410
}
411
 
412
/**
759 palkovsky 413
 * Try to find object in CPU-cache magazines
414
 *
415
 * @return Pointer to object or NULL if not available
416
 */
417
static void * magazine_obj_get(slab_cache_t *cache)
418
{
419
	slab_magazine_t *mag;
767 palkovsky 420
	void *obj;
759 palkovsky 421
 
772 palkovsky 422
	if (!CPU)
423
		return NULL;
424
 
759 palkovsky 425
	spinlock_lock(&cache->mag_cache[CPU->id].lock);
426
 
769 palkovsky 427
	mag = get_full_current_mag(cache);
428
	if (!mag) {
429
		spinlock_unlock(&cache->mag_cache[CPU->id].lock);
430
		return NULL;
759 palkovsky 431
	}
767 palkovsky 432
	obj = mag->objs[--mag->busy];
759 palkovsky 433
	spinlock_unlock(&cache->mag_cache[CPU->id].lock);
767 palkovsky 434
	atomic_dec(&cache->cached_objs);
435
 
436
	return obj;
759 palkovsky 437
}
438
 
439
/**
768 palkovsky 440
 * Assure that the current magazine is empty, return pointer to it, or NULL if 
769 palkovsky 441
 * no empty magazine is available and cannot be allocated
759 palkovsky 442
 *
773 palkovsky 443
 * Assume mag_cache[CPU->id].lock is held
444
 *
759 palkovsky 445
 * We have 2 magazines bound to processor. 
446
 * First try the current. 
447
 *  If full, try the last.
448
 *   If full, put to magazines list.
449
 *   allocate new, exchange last & current
450
 *
768 palkovsky 451
 */
452
static slab_magazine_t * make_empty_current_mag(slab_cache_t *cache)
453
{
454
	slab_magazine_t *cmag,*lastmag,*newmag;
455
 
456
	cmag = cache->mag_cache[CPU->id].current;
457
	lastmag = cache->mag_cache[CPU->id].last;
458
 
459
	if (cmag) {
460
		if (cmag->busy < cmag->size)
461
			return cmag;
462
		if (lastmag && lastmag->busy < lastmag->size) {
463
			cache->mag_cache[CPU->id].last = cmag;
464
			cache->mag_cache[CPU->id].current = lastmag;
465
			return lastmag;
466
		}
467
	}
468
	/* current | last are full | nonexistent, allocate new */
469
	/* We do not want to sleep just because of caching */
470
	/* Especially we do not want reclaiming to start, as 
471
	 * this would deadlock */
472
	newmag = slab_alloc(&mag_cache, FRAME_ATOMIC | FRAME_NO_RECLAIM);
473
	if (!newmag)
474
		return NULL;
475
	newmag->size = SLAB_MAG_SIZE;
476
	newmag->busy = 0;
477
 
478
	/* Flush last to magazine list */
781 palkovsky 479
	if (lastmag)
480
		put_mag_to_cache(cache, lastmag);
481
 
768 palkovsky 482
	/* Move current as last, save new as current */
483
	cache->mag_cache[CPU->id].last = cmag;	
484
	cache->mag_cache[CPU->id].current = newmag;	
485
 
486
	return newmag;
487
}
488
 
489
/**
490
 * Put object into CPU-cache magazine
491
 *
759 palkovsky 492
 * @return 0 - success, -1 - could not get memory
493
 */
494
static int magazine_obj_put(slab_cache_t *cache, void *obj)
495
{
496
	slab_magazine_t *mag;
497
 
772 palkovsky 498
	if (!CPU)
499
		return -1;
500
 
759 palkovsky 501
	spinlock_lock(&cache->mag_cache[CPU->id].lock);
768 palkovsky 502
 
503
	mag = make_empty_current_mag(cache);
769 palkovsky 504
	if (!mag) {
505
		spinlock_unlock(&cache->mag_cache[CPU->id].lock);
506
		return -1;
507
	}
759 palkovsky 508
 
509
	mag->objs[mag->busy++] = obj;
510
 
511
	spinlock_unlock(&cache->mag_cache[CPU->id].lock);
767 palkovsky 512
	atomic_inc(&cache->cached_objs);
759 palkovsky 513
	return 0;
514
}
515
 
516
 
517
/**************************************/
762 palkovsky 518
/* SLAB CACHE functions */
759 palkovsky 519
 
762 palkovsky 520
/** Return number of objects that fit in certain cache size */
521
static int comp_objects(slab_cache_t *cache)
522
{
523
	if (cache->flags & SLAB_CACHE_SLINSIDE)
524
		return ((PAGE_SIZE << cache->order) - sizeof(slab_t)) / cache->size;
525
	else 
526
		return (PAGE_SIZE << cache->order) / cache->size;
527
}
528
 
529
/** Return wasted space in slab */
530
static int badness(slab_cache_t *cache)
531
{
532
	int objects;
533
	int ssize;
534
 
535
	objects = comp_objects(cache);
536
	ssize = PAGE_SIZE << cache->order;
537
	if (cache->flags & SLAB_CACHE_SLINSIDE)
538
		ssize -= sizeof(slab_t);
539
	return ssize - objects*cache->size;
540
}
541
 
789 palkovsky 542
/**
543
 * Initialize mag_cache structure in slab cache
544
 */
545
static void make_magcache(slab_cache_t *cache)
546
{
547
	int i;
791 palkovsky 548
 
549
	ASSERT(_slab_initialized >= 2);
789 palkovsky 550
 
791 palkovsky 551
	cache->mag_cache = kalloc(sizeof(slab_mag_cache_t)*config.cpu_count,0);
789 palkovsky 552
	for (i=0; i < config.cpu_count; i++) {
553
		memsetb((__address)&cache->mag_cache[i],
554
			sizeof(cache->mag_cache[i]), 0);
555
		spinlock_initialize(&cache->mag_cache[i].lock, 
556
				    "slab_maglock_cpu");
557
	}
558
}
559
 
759 palkovsky 560
/** Initialize allocated memory as a slab cache */
561
static void
562
_slab_cache_create(slab_cache_t *cache,
563
		   char *name,
564
		   size_t size,
565
		   size_t align,
566
		   int (*constructor)(void *obj, int kmflag),
787 palkovsky 567
		   int (*destructor)(void *obj),
759 palkovsky 568
		   int flags)
569
{
771 palkovsky 570
	int pages;
783 palkovsky 571
	ipl_t ipl;
759 palkovsky 572
 
573
	memsetb((__address)cache, sizeof(*cache), 0);
574
	cache->name = name;
575
 
766 palkovsky 576
	if (align < sizeof(__native))
577
		align = sizeof(__native);
578
	size = ALIGN_UP(size, align);
579
 
762 palkovsky 580
	cache->size = size;
759 palkovsky 581
 
582
	cache->constructor = constructor;
583
	cache->destructor = destructor;
584
	cache->flags = flags;
585
 
586
	list_initialize(&cache->full_slabs);
587
	list_initialize(&cache->partial_slabs);
588
	list_initialize(&cache->magazines);
776 palkovsky 589
	spinlock_initialize(&cache->slablock, "slab_lock");
590
	spinlock_initialize(&cache->maglock, "slab_maglock");
789 palkovsky 591
	if (! (cache->flags & SLAB_CACHE_NOMAGAZINE))
592
		make_magcache(cache);
759 palkovsky 593
 
594
	/* Compute slab sizes, object counts in slabs etc. */
595
	if (cache->size < SLAB_INSIDE_SIZE)
596
		cache->flags |= SLAB_CACHE_SLINSIDE;
597
 
762 palkovsky 598
	/* Minimum slab order */
771 palkovsky 599
	pages = ((cache->size-1) >> PAGE_WIDTH) + 1;
600
	cache->order = fnzb(pages);
766 palkovsky 601
 
762 palkovsky 602
	while (badness(cache) > SLAB_MAX_BADNESS(cache)) {
603
		cache->order += 1;
604
	}
605
	cache->objects = comp_objects(cache);
766 palkovsky 606
	/* If info fits in, put it inside */
607
	if (badness(cache) > sizeof(slab_t))
608
		cache->flags |= SLAB_CACHE_SLINSIDE;
762 palkovsky 609
 
783 palkovsky 610
	/* Add cache to cache list */
611
	ipl = interrupts_disable();
759 palkovsky 612
	spinlock_lock(&slab_cache_lock);
613
 
614
	list_append(&cache->link, &slab_cache_list);
615
 
616
	spinlock_unlock(&slab_cache_lock);
783 palkovsky 617
	interrupts_restore(ipl);
759 palkovsky 618
}
619
 
620
/** Create slab cache  */
621
slab_cache_t * slab_cache_create(char *name,
622
				 size_t size,
623
				 size_t align,
624
				 int (*constructor)(void *obj, int kmflag),
787 palkovsky 625
				 int (*destructor)(void *obj),
759 palkovsky 626
				 int flags)
627
{
628
	slab_cache_t *cache;
629
 
769 palkovsky 630
	cache = slab_alloc(&slab_cache_cache, 0);
759 palkovsky 631
	_slab_cache_create(cache, name, size, align, constructor, destructor,
632
			   flags);
633
	return cache;
634
}
635
 
636
/** 
637
 * Reclaim space occupied by objects that are already free
638
 *
639
 * @param flags If contains SLAB_RECLAIM_ALL, do aggressive freeing
640
 * @return Number of freed pages
641
 */
642
static count_t _slab_reclaim(slab_cache_t *cache, int flags)
643
{
644
	int i;
645
	slab_magazine_t *mag;
646
	count_t frames = 0;
781 palkovsky 647
	int magcount;
759 palkovsky 648
 
649
	if (cache->flags & SLAB_CACHE_NOMAGAZINE)
650
		return 0; /* Nothing to do */
781 palkovsky 651
 
652
	/* We count up to original magazine count to avoid
653
	 * endless loop 
654
	 */
655
	magcount = atomic_get(&cache->magazine_counter);
656
	while (magcount-- && (mag=get_mag_from_cache(cache,0))) {
657
		frames += magazine_destroy(cache,mag);
658
		if (!(flags & SLAB_RECLAIM_ALL) && frames)
659
			break;
769 palkovsky 660
	}
759 palkovsky 661
 
662
	if (flags & SLAB_RECLAIM_ALL) {
781 palkovsky 663
		/* Free cpu-bound magazines */
759 palkovsky 664
		/* Destroy CPU magazines */
665
		for (i=0; i<config.cpu_count; i++) {
781 palkovsky 666
			spinlock_lock(&cache->mag_cache[i].lock);
667
 
759 palkovsky 668
			mag = cache->mag_cache[i].current;
669
			if (mag)
670
				frames += magazine_destroy(cache, mag);
671
			cache->mag_cache[i].current = NULL;
672
 
673
			mag = cache->mag_cache[i].last;
674
			if (mag)
675
				frames += magazine_destroy(cache, mag);
676
			cache->mag_cache[i].last = NULL;
781 palkovsky 677
 
678
			spinlock_unlock(&cache->mag_cache[i].lock);
759 palkovsky 679
		}
680
	}
767 palkovsky 681
 
759 palkovsky 682
	return frames;
683
}
684
 
685
/** Check that there are no slabs and remove cache from system  */
686
void slab_cache_destroy(slab_cache_t *cache)
687
{
781 palkovsky 688
	ipl_t ipl;
689
 
690
	/* First remove cache from link, so that we don't need
691
	 * to disable interrupts later
692
	 */
693
 
694
	ipl = interrupts_disable();
695
	spinlock_lock(&slab_cache_lock);
696
 
697
	list_remove(&cache->link);
698
 
699
	spinlock_unlock(&slab_cache_lock);
700
	interrupts_restore(ipl);
701
 
759 palkovsky 702
	/* Do not lock anything, we assume the software is correct and
703
	 * does not touch the cache when it decides to destroy it */
704
 
705
	/* Destroy all magazines */
706
	_slab_reclaim(cache, SLAB_RECLAIM_ALL);
707
 
708
	/* All slabs must be empty */
709
	if (!list_empty(&cache->full_slabs) \
710
	    || !list_empty(&cache->partial_slabs))
711
		panic("Destroying cache that is not empty.");
712
 
789 palkovsky 713
	if (!(cache->flags & SLAB_CACHE_NOMAGAZINE))
791 palkovsky 714
		kfree(cache->mag_cache);
769 palkovsky 715
	slab_free(&slab_cache_cache, cache);
759 palkovsky 716
}
717
 
718
/** Allocate new object from cache - if no flags given, always returns 
719
    memory */
720
void * slab_alloc(slab_cache_t *cache, int flags)
721
{
722
	ipl_t ipl;
723
	void *result = NULL;
773 palkovsky 724
 
759 palkovsky 725
	/* Disable interrupts to avoid deadlocks with interrupt handlers */
726
	ipl = interrupts_disable();
771 palkovsky 727
 
772 palkovsky 728
	if (!(cache->flags & SLAB_CACHE_NOMAGAZINE))
759 palkovsky 729
		result = magazine_obj_get(cache);
776 palkovsky 730
	if (!result)
759 palkovsky 731
		result = slab_obj_create(cache, flags);
732
 
769 palkovsky 733
	interrupts_restore(ipl);
734
 
764 palkovsky 735
	if (result)
736
		atomic_inc(&cache->allocated_objs);
737
 
759 palkovsky 738
	return result;
739
}
740
 
771 palkovsky 741
/** Return object to cache, use slab if known  */
742
static void _slab_free(slab_cache_t *cache, void *obj, slab_t *slab)
759 palkovsky 743
{
744
	ipl_t ipl;
745
 
746
	ipl = interrupts_disable();
747
 
762 palkovsky 748
	if ((cache->flags & SLAB_CACHE_NOMAGAZINE) \
749
	    || magazine_obj_put(cache, obj)) {
776 palkovsky 750
 
771 palkovsky 751
		slab_obj_destroy(cache, obj, slab);
776 palkovsky 752
 
759 palkovsky 753
	}
769 palkovsky 754
	interrupts_restore(ipl);
764 palkovsky 755
	atomic_dec(&cache->allocated_objs);
759 palkovsky 756
}
757
 
771 palkovsky 758
/** Return slab object to cache */
759
void slab_free(slab_cache_t *cache, void *obj)
760
{
761
	_slab_free(cache,obj,NULL);
762
}
763
 
759 palkovsky 764
/* Go through all caches and reclaim what is possible */
765
count_t slab_reclaim(int flags)
766
{
767
	slab_cache_t *cache;
768
	link_t *cur;
769
	count_t frames = 0;
770
 
771
	spinlock_lock(&slab_cache_lock);
772
 
776 palkovsky 773
	/* TODO: Add assert, that interrupts are disabled, otherwise
774
	 * memory allocation from interrupts can deadlock.
775
	 */
776
 
759 palkovsky 777
	for (cur = slab_cache_list.next;cur!=&slab_cache_list; cur=cur->next) {
778
		cache = list_get_instance(cur, slab_cache_t, link);
779
		frames += _slab_reclaim(cache, flags);
780
	}
781
 
782
	spinlock_unlock(&slab_cache_lock);
783
 
784
	return frames;
785
}
786
 
787
 
788
/* Print list of slabs */
789
void slab_print_list(void)
790
{
791
	slab_cache_t *cache;
792
	link_t *cur;
783 palkovsky 793
	ipl_t ipl;
794
 
795
	ipl = interrupts_disable();
759 palkovsky 796
	spinlock_lock(&slab_cache_lock);
767 palkovsky 797
	printf("SLAB name\tOsize\tPages\tObj/pg\tSlabs\tCached\tAllocobjs\tCtl\n");
759 palkovsky 798
	for (cur = slab_cache_list.next;cur!=&slab_cache_list; cur=cur->next) {
799
		cache = list_get_instance(cur, slab_cache_t, link);
767 palkovsky 800
		printf("%s\t%d\t%d\t%d\t%d\t%d\t%d\t\t%s\n", cache->name, cache->size, 
766 palkovsky 801
		       (1 << cache->order), cache->objects,
767 palkovsky 802
		       atomic_get(&cache->allocated_slabs),
803
		       atomic_get(&cache->cached_objs),
766 palkovsky 804
		       atomic_get(&cache->allocated_objs),
805
		       cache->flags & SLAB_CACHE_SLINSIDE ? "In" : "Out");
759 palkovsky 806
	}
807
	spinlock_unlock(&slab_cache_lock);
783 palkovsky 808
	interrupts_restore(ipl);
759 palkovsky 809
}
810
 
811
void slab_cache_init(void)
812
{
771 palkovsky 813
	int i, size;
814
 
759 palkovsky 815
	/* Initialize magazine cache */
816
	_slab_cache_create(&mag_cache,
817
			   "slab_magazine",
818
			   sizeof(slab_magazine_t)+SLAB_MAG_SIZE*sizeof(void*),
819
			   sizeof(__address),
820
			   NULL, NULL,
769 palkovsky 821
			   SLAB_CACHE_NOMAGAZINE | SLAB_CACHE_SLINSIDE);
822
	/* Initialize slab_cache cache */
823
	_slab_cache_create(&slab_cache_cache,
824
			   "slab_cache",
789 palkovsky 825
			   sizeof(slab_cache_cache),
769 palkovsky 826
			   sizeof(__address),
827
			   NULL, NULL,
828
			   SLAB_CACHE_NOMAGAZINE | SLAB_CACHE_SLINSIDE);
829
	/* Initialize external slab cache */
830
	slab_extern_cache = slab_cache_create("slab_extern",
831
					      sizeof(slab_t),
832
					      0, NULL, NULL,
789 palkovsky 833
					      SLAB_CACHE_SLINSIDE | SLAB_CACHE_MAGDEFERRED);
759 palkovsky 834
 
835
	/* Initialize structures for malloc */
771 palkovsky 836
	for (i=0, size=(1<<SLAB_MIN_MALLOC_W);
837
	     i < (SLAB_MAX_MALLOC_W-SLAB_MIN_MALLOC_W+1);
838
	     i++, size <<= 1) {
839
		malloc_caches[i] = slab_cache_create(malloc_names[i],
840
						     size, 0,
789 palkovsky 841
						     NULL,NULL, SLAB_CACHE_MAGDEFERRED);
771 palkovsky 842
	}
778 palkovsky 843
#ifdef CONFIG_DEBUG       
844
	_slab_initialized = 1;
845
#endif
759 palkovsky 846
}
771 palkovsky 847
 
789 palkovsky 848
/** Enable cpu_cache
849
 *
850
 * Kernel calls this function, when it knows the real number of
851
 * processors. 
852
 * Allocate slab for cpucache and enable it on all existing
853
 * slabs that are SLAB_CACHE_MAGDEFERRED
854
 */
855
void slab_enable_cpucache(void)
856
{
857
	link_t *cur;
858
	slab_cache_t *s;
859
 
791 palkovsky 860
#ifdef CONFIG_DEBUG
861
	_slab_initialized = 2;
862
#endif
863
 
789 palkovsky 864
	spinlock_lock(&slab_cache_lock);
865
 
866
	for (cur=slab_cache_list.next; cur != &slab_cache_list;cur=cur->next){
867
		s = list_get_instance(cur, slab_cache_t, link);
868
		if ((s->flags & SLAB_CACHE_MAGDEFERRED) != SLAB_CACHE_MAGDEFERRED)
869
			continue;
870
		make_magcache(s);
871
		s->flags &= ~SLAB_CACHE_MAGDEFERRED;
872
	}
873
 
874
	spinlock_unlock(&slab_cache_lock);
875
}
876
 
771 palkovsky 877
/**************************************/
878
/* kalloc/kfree functions             */
879
void * kalloc(unsigned int size, int flags)
880
{
881
	int idx;
778 palkovsky 882
 
883
	ASSERT(_slab_initialized);
771 palkovsky 884
	ASSERT( size && size <= (1 << SLAB_MAX_MALLOC_W));
885
 
886
	if (size < (1 << SLAB_MIN_MALLOC_W))
887
		size = (1 << SLAB_MIN_MALLOC_W);
888
 
889
	idx = fnzb(size-1) - SLAB_MIN_MALLOC_W + 1;
890
 
891
	return slab_alloc(malloc_caches[idx], flags);
892
}
893
 
894
 
895
void kfree(void *obj)
896
{
781 palkovsky 897
	slab_t *slab;
898
 
899
	if (!obj) return;
900
 
901
	slab = obj2slab(obj);
771 palkovsky 902
	_slab_free(slab->cache, obj, slab);
903
}