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759 palkovsky 1
/*
2071 jermar 2
 * Copyright (c) 2006 Ondrej Palkovsky
759 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
 
1757 jermar 29
/** @addtogroup genericmm
1702 cejka 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
 *
1757 jermar 86
 * @todo
1248 jermar 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
 *
1757 jermar 96
 * @todo
97
 * it might be good to add granularity of locks even to slab level,
98
 * we could then try_spinlock over all partial slabs and thus improve
99
 * scalability even on slab level
769 palkovsky 100
 */
101
 
759 palkovsky 102
#include <synch/spinlock.h>
103
#include <mm/slab.h>
788 jermar 104
#include <adt/list.h>
759 palkovsky 105
#include <memstr.h>
106
#include <align.h>
762 palkovsky 107
#include <mm/frame.h>
759 palkovsky 108
#include <config.h>
109
#include <print.h>
110
#include <arch.h>
111
#include <panic.h>
762 palkovsky 112
#include <debug.h>
771 palkovsky 113
#include <bitops.h>
759 palkovsky 114
 
115
SPINLOCK_INITIALIZE(slab_cache_lock);
769 palkovsky 116
static LIST_INITIALIZE(slab_cache_list);
759 palkovsky 117
 
769 palkovsky 118
/** Magazine cache */
119
static slab_cache_t mag_cache;
120
/** Cache for cache descriptors */
121
static slab_cache_t slab_cache_cache;
122
/** Cache for external slab descriptors
123
 * This time we want per-cpu cache, so do not make it static
1248 jermar 124
 * - using slab for internal slab structures will not deadlock,
769 palkovsky 125
 *   as all slab structures are 'small' - control structures of
126
 *   their caches do not require further allocation
127
 */
128
static slab_cache_t *slab_extern_cache;
771 palkovsky 129
/** Caches for malloc */
130
static slab_cache_t *malloc_caches[SLAB_MAX_MALLOC_W-SLAB_MIN_MALLOC_W+1];
131
char *malloc_names[] =  {
791 palkovsky 132
	"malloc-16","malloc-32","malloc-64","malloc-128",
771 palkovsky 133
	"malloc-256","malloc-512","malloc-1K","malloc-2K",
134
	"malloc-4K","malloc-8K","malloc-16K","malloc-32K",
1428 palkovsky 135
	"malloc-64K","malloc-128K","malloc-256K"
771 palkovsky 136
};
762 palkovsky 137
 
769 palkovsky 138
/** Slab descriptor */
762 palkovsky 139
typedef struct {
1950 jermar 140
	slab_cache_t *cache; 	/**< Pointer to parent cache. */
141
	link_t link;       	/**< List of full/partial slabs. */
142
	void *start;       	/**< Start address of first available item. */
143
	count_t available; 	/**< Count of available items in this slab. */
144
	index_t nextavail; 	/**< The index of next available item. */
762 palkovsky 145
}slab_t;
146
 
791 palkovsky 147
#ifdef CONFIG_DEBUG
148
static int _slab_initialized = 0;
149
#endif
150
 
759 palkovsky 151
/**************************************/
1248 jermar 152
/* Slab allocation functions          */
759 palkovsky 153
 
762 palkovsky 154
/**
155
 * Allocate frames for slab space and initialize
156
 *
157
 */
158
static slab_t * slab_space_alloc(slab_cache_t *cache, int flags)
159
{
160
	void *data;
161
	slab_t *slab;
162
	size_t fsize;
163
	int i;
2123 decky 164
	unsigned int zone = 0;
814 palkovsky 165
 
1766 palkovsky 166
	data = frame_alloc_generic(cache->order, FRAME_KA | flags, &zone);
167
	if (!data) {
762 palkovsky 168
		return NULL;
764 palkovsky 169
	}
768 palkovsky 170
	if (! (cache->flags & SLAB_CACHE_SLINSIDE)) {
769 palkovsky 171
		slab = slab_alloc(slab_extern_cache, flags);
762 palkovsky 172
		if (!slab) {
1760 palkovsky 173
			frame_free(KA2PA(data));
762 palkovsky 174
			return NULL;
175
		}
176
	} else {
177
		fsize = (PAGE_SIZE << cache->order);
178
		slab = data + fsize - sizeof(*slab);
179
	}
1288 jermar 180
 
762 palkovsky 181
	/* Fill in slab structures */
814 palkovsky 182
	for (i=0; i < (1 << cache->order); i++)
1760 palkovsky 183
		frame_set_parent(ADDR2PFN(KA2PA(data))+i, slab, zone);
762 palkovsky 184
 
185
	slab->start = data;
186
	slab->available = cache->objects;
187
	slab->nextavail = 0;
767 palkovsky 188
	slab->cache = cache;
762 palkovsky 189
 
190
	for (i=0; i<cache->objects;i++)
191
		*((int *) (slab->start + i*cache->size)) = i+1;
764 palkovsky 192
 
193
	atomic_inc(&cache->allocated_slabs);
762 palkovsky 194
	return slab;
195
}
196
 
759 palkovsky 197
/**
1248 jermar 198
 * Deallocate space associated with slab
762 palkovsky 199
 *
200
 * @return number of freed frames
201
 */
202
static count_t slab_space_free(slab_cache_t *cache, slab_t *slab)
203
{
1760 palkovsky 204
	frame_free(KA2PA(slab->start));
768 palkovsky 205
	if (! (cache->flags & SLAB_CACHE_SLINSIDE))
769 palkovsky 206
		slab_free(slab_extern_cache, slab);
764 palkovsky 207
 
208
	atomic_dec(&cache->allocated_slabs);
209
 
762 palkovsky 210
	return 1 << cache->order;
211
}
212
 
213
/** Map object to slab structure */
214
static slab_t * obj2slab(void *obj)
215
{
814 palkovsky 216
	return (slab_t *)frame_get_parent(ADDR2PFN(KA2PA(obj)), 0);
762 palkovsky 217
}
218
 
219
/**************************************/
1248 jermar 220
/* Slab functions */
762 palkovsky 221
 
222
 
223
/**
759 palkovsky 224
 * Return object to slab and call a destructor
225
 *
762 palkovsky 226
 * @param slab If the caller knows directly slab of the object, otherwise NULL
227
 *
759 palkovsky 228
 * @return Number of freed pages
229
 */
762 palkovsky 230
static count_t slab_obj_destroy(slab_cache_t *cache, void *obj,
231
				slab_t *slab)
759 palkovsky 232
{
787 palkovsky 233
	int freed = 0;
234
 
762 palkovsky 235
	if (!slab)
236
		slab = obj2slab(obj);
237
 
767 palkovsky 238
	ASSERT(slab->cache == cache);
239
 
787 palkovsky 240
	if (cache->destructor)
241
		freed = cache->destructor(obj);
242
 
776 palkovsky 243
	spinlock_lock(&cache->slablock);
789 palkovsky 244
	ASSERT(slab->available < cache->objects);
776 palkovsky 245
 
762 palkovsky 246
	*((int *)obj) = slab->nextavail;
247
	slab->nextavail = (obj - slab->start)/cache->size;
248
	slab->available++;
249
 
250
	/* Move it to correct list */
251
	if (slab->available == cache->objects) {
252
		/* Free associated memory */
253
		list_remove(&slab->link);
782 palkovsky 254
		spinlock_unlock(&cache->slablock);
255
 
787 palkovsky 256
		return freed + slab_space_free(cache, slab);
782 palkovsky 257
 
780 palkovsky 258
	} else if (slab->available == 1) {
259
		/* It was in full, move to partial */
260
		list_remove(&slab->link);
261
		list_prepend(&slab->link, &cache->partial_slabs);
762 palkovsky 262
	}
783 palkovsky 263
	spinlock_unlock(&cache->slablock);
787 palkovsky 264
	return freed;
759 palkovsky 265
}
266
 
267
/**
268
 * Take new object from slab or create new if needed
269
 *
270
 * @return Object address or null
271
 */
272
static void * slab_obj_create(slab_cache_t *cache, int flags)
273
{
762 palkovsky 274
	slab_t *slab;
275
	void *obj;
276
 
776 palkovsky 277
	spinlock_lock(&cache->slablock);
278
 
762 palkovsky 279
	if (list_empty(&cache->partial_slabs)) {
280
		/* Allow recursion and reclaiming
1248 jermar 281
		 * - this should work, as the slab control structures
1288 jermar 282
		 *   are small and do not need to allocate with anything
283
		 *   other than frame_alloc when they are allocating,
762 palkovsky 284
		 *   that's why we should get recursion at most 1-level deep
285
		 */
776 palkovsky 286
		spinlock_unlock(&cache->slablock);
762 palkovsky 287
		slab = slab_space_alloc(cache, flags);
780 palkovsky 288
		if (!slab)
289
			return NULL;
776 palkovsky 290
		spinlock_lock(&cache->slablock);
762 palkovsky 291
	} else {
1950 jermar 292
		slab = list_get_instance(cache->partial_slabs.next, slab_t, link);
762 palkovsky 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
 
1950 jermar 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
/**************************************/
1248 jermar 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
 
789 palkovsky 539
/**
540
 * Initialize mag_cache structure in slab cache
541
 */
542
static void make_magcache(slab_cache_t *cache)
543
{
544
	int i;
791 palkovsky 545
 
546
	ASSERT(_slab_initialized >= 2);
789 palkovsky 547
 
822 palkovsky 548
	cache->mag_cache = malloc(sizeof(slab_mag_cache_t)*config.cpu_count,0);
789 palkovsky 549
	for (i=0; i < config.cpu_count; i++) {
1780 jermar 550
		memsetb((uintptr_t)&cache->mag_cache[i],
789 palkovsky 551
			sizeof(cache->mag_cache[i]), 0);
552
		spinlock_initialize(&cache->mag_cache[i].lock, 
553
				    "slab_maglock_cpu");
554
	}
555
}
556
 
759 palkovsky 557
/** Initialize allocated memory as a slab cache */
558
static void
559
_slab_cache_create(slab_cache_t *cache,
560
		   char *name,
561
		   size_t size,
562
		   size_t align,
563
		   int (*constructor)(void *obj, int kmflag),
787 palkovsky 564
		   int (*destructor)(void *obj),
759 palkovsky 565
		   int flags)
566
{
771 palkovsky 567
	int pages;
783 palkovsky 568
	ipl_t ipl;
759 palkovsky 569
 
1780 jermar 570
	memsetb((uintptr_t)cache, sizeof(*cache), 0);
759 palkovsky 571
	cache->name = name;
572
 
1780 jermar 573
	if (align < sizeof(unative_t))
574
		align = sizeof(unative_t);
766 palkovsky 575
	size = ALIGN_UP(size, align);
576
 
762 palkovsky 577
	cache->size = size;
759 palkovsky 578
 
579
	cache->constructor = constructor;
580
	cache->destructor = destructor;
581
	cache->flags = flags;
582
 
583
	list_initialize(&cache->full_slabs);
584
	list_initialize(&cache->partial_slabs);
585
	list_initialize(&cache->magazines);
776 palkovsky 586
	spinlock_initialize(&cache->slablock, "slab_lock");
587
	spinlock_initialize(&cache->maglock, "slab_maglock");
789 palkovsky 588
	if (! (cache->flags & SLAB_CACHE_NOMAGAZINE))
589
		make_magcache(cache);
759 palkovsky 590
 
591
	/* Compute slab sizes, object counts in slabs etc. */
592
	if (cache->size < SLAB_INSIDE_SIZE)
593
		cache->flags |= SLAB_CACHE_SLINSIDE;
594
 
762 palkovsky 595
	/* Minimum slab order */
1682 palkovsky 596
	pages = SIZE2FRAMES(cache->size);
1677 palkovsky 597
	/* We need the 2^order >= pages */
598
	if (pages == 1)
599
		cache->order = 0;
600
	else
601
		cache->order = fnzb(pages-1)+1;
766 palkovsky 602
 
762 palkovsky 603
	while (badness(cache) > SLAB_MAX_BADNESS(cache)) {
604
		cache->order += 1;
605
	}
606
	cache->objects = comp_objects(cache);
766 palkovsky 607
	/* If info fits in, put it inside */
608
	if (badness(cache) > sizeof(slab_t))
609
		cache->flags |= SLAB_CACHE_SLINSIDE;
762 palkovsky 610
 
783 palkovsky 611
	/* Add cache to cache list */
612
	ipl = interrupts_disable();
759 palkovsky 613
	spinlock_lock(&slab_cache_lock);
614
 
615
	list_append(&cache->link, &slab_cache_list);
616
 
617
	spinlock_unlock(&slab_cache_lock);
783 palkovsky 618
	interrupts_restore(ipl);
759 palkovsky 619
}
620
 
621
/** Create slab cache  */
622
slab_cache_t * slab_cache_create(char *name,
623
				 size_t size,
624
				 size_t align,
625
				 int (*constructor)(void *obj, int kmflag),
787 palkovsky 626
				 int (*destructor)(void *obj),
759 palkovsky 627
				 int flags)
628
{
629
	slab_cache_t *cache;
630
 
769 palkovsky 631
	cache = slab_alloc(&slab_cache_cache, 0);
759 palkovsky 632
	_slab_cache_create(cache, name, size, align, constructor, destructor,
633
			   flags);
634
	return cache;
635
}
636
 
637
/** 
638
 * Reclaim space occupied by objects that are already free
639
 *
640
 * @param flags If contains SLAB_RECLAIM_ALL, do aggressive freeing
641
 * @return Number of freed pages
642
 */
643
static count_t _slab_reclaim(slab_cache_t *cache, int flags)
644
{
645
	int i;
646
	slab_magazine_t *mag;
647
	count_t frames = 0;
781 palkovsky 648
	int magcount;
759 palkovsky 649
 
650
	if (cache->flags & SLAB_CACHE_NOMAGAZINE)
651
		return 0; /* Nothing to do */
781 palkovsky 652
 
653
	/* We count up to original magazine count to avoid
654
	 * endless loop 
655
	 */
656
	magcount = atomic_get(&cache->magazine_counter);
657
	while (magcount-- && (mag=get_mag_from_cache(cache,0))) {
658
		frames += magazine_destroy(cache,mag);
659
		if (!(flags & SLAB_RECLAIM_ALL) && frames)
660
			break;
769 palkovsky 661
	}
759 palkovsky 662
 
663
	if (flags & SLAB_RECLAIM_ALL) {
781 palkovsky 664
		/* Free cpu-bound magazines */
759 palkovsky 665
		/* Destroy CPU magazines */
666
		for (i=0; i<config.cpu_count; i++) {
781 palkovsky 667
			spinlock_lock(&cache->mag_cache[i].lock);
668
 
759 palkovsky 669
			mag = cache->mag_cache[i].current;
670
			if (mag)
671
				frames += magazine_destroy(cache, mag);
672
			cache->mag_cache[i].current = NULL;
673
 
674
			mag = cache->mag_cache[i].last;
675
			if (mag)
676
				frames += magazine_destroy(cache, mag);
677
			cache->mag_cache[i].last = NULL;
781 palkovsky 678
 
679
			spinlock_unlock(&cache->mag_cache[i].lock);
759 palkovsky 680
		}
681
	}
767 palkovsky 682
 
759 palkovsky 683
	return frames;
684
}
685
 
686
/** Check that there are no slabs and remove cache from system  */
687
void slab_cache_destroy(slab_cache_t *cache)
688
{
781 palkovsky 689
	ipl_t ipl;
690
 
691
	/* First remove cache from link, so that we don't need
692
	 * to disable interrupts later
693
	 */
694
 
695
	ipl = interrupts_disable();
696
	spinlock_lock(&slab_cache_lock);
697
 
698
	list_remove(&cache->link);
699
 
700
	spinlock_unlock(&slab_cache_lock);
701
	interrupts_restore(ipl);
702
 
759 palkovsky 703
	/* Do not lock anything, we assume the software is correct and
704
	 * does not touch the cache when it decides to destroy it */
705
 
706
	/* Destroy all magazines */
707
	_slab_reclaim(cache, SLAB_RECLAIM_ALL);
708
 
709
	/* All slabs must be empty */
710
	if (!list_empty(&cache->full_slabs) \
711
	    || !list_empty(&cache->partial_slabs))
712
		panic("Destroying cache that is not empty.");
713
 
789 palkovsky 714
	if (!(cache->flags & SLAB_CACHE_NOMAGAZINE))
822 palkovsky 715
		free(cache->mag_cache);
769 palkovsky 716
	slab_free(&slab_cache_cache, cache);
759 palkovsky 717
}
718
 
719
/** Allocate new object from cache - if no flags given, always returns 
720
    memory */
721
void * slab_alloc(slab_cache_t *cache, int flags)
722
{
723
	ipl_t ipl;
724
	void *result = NULL;
773 palkovsky 725
 
759 palkovsky 726
	/* Disable interrupts to avoid deadlocks with interrupt handlers */
727
	ipl = interrupts_disable();
771 palkovsky 728
 
814 palkovsky 729
	if (!(cache->flags & SLAB_CACHE_NOMAGAZINE)) {
759 palkovsky 730
		result = magazine_obj_get(cache);
814 palkovsky 731
	}
776 palkovsky 732
	if (!result)
759 palkovsky 733
		result = slab_obj_create(cache, flags);
734
 
769 palkovsky 735
	interrupts_restore(ipl);
736
 
764 palkovsky 737
	if (result)
738
		atomic_inc(&cache->allocated_objs);
739
 
759 palkovsky 740
	return result;
741
}
742
 
771 palkovsky 743
/** Return object to cache, use slab if known  */
744
static void _slab_free(slab_cache_t *cache, void *obj, slab_t *slab)
759 palkovsky 745
{
746
	ipl_t ipl;
747
 
748
	ipl = interrupts_disable();
749
 
762 palkovsky 750
	if ((cache->flags & SLAB_CACHE_NOMAGAZINE) \
751
	    || magazine_obj_put(cache, obj)) {
776 palkovsky 752
 
771 palkovsky 753
		slab_obj_destroy(cache, obj, slab);
776 palkovsky 754
 
759 palkovsky 755
	}
769 palkovsky 756
	interrupts_restore(ipl);
764 palkovsky 757
	atomic_dec(&cache->allocated_objs);
759 palkovsky 758
}
759
 
771 palkovsky 760
/** Return slab object to cache */
761
void slab_free(slab_cache_t *cache, void *obj)
762
{
763
	_slab_free(cache,obj,NULL);
764
}
765
 
759 palkovsky 766
/* Go through all caches and reclaim what is possible */
767
count_t slab_reclaim(int flags)
768
{
769
	slab_cache_t *cache;
770
	link_t *cur;
771
	count_t frames = 0;
772
 
773
	spinlock_lock(&slab_cache_lock);
774
 
776 palkovsky 775
	/* TODO: Add assert, that interrupts are disabled, otherwise
776
	 * memory allocation from interrupts can deadlock.
777
	 */
778
 
759 palkovsky 779
	for (cur = slab_cache_list.next;cur!=&slab_cache_list; cur=cur->next) {
780
		cache = list_get_instance(cur, slab_cache_t, link);
781
		frames += _slab_reclaim(cache, flags);
782
	}
783
 
784
	spinlock_unlock(&slab_cache_lock);
785
 
786
	return frames;
787
}
788
 
789
 
790
/* Print list of slabs */
791
void slab_print_list(void)
792
{
793
	slab_cache_t *cache;
794
	link_t *cur;
783 palkovsky 795
	ipl_t ipl;
796
 
797
	ipl = interrupts_disable();
759 palkovsky 798
	spinlock_lock(&slab_cache_lock);
2052 decky 799
	printf("slab name        size     pages  obj/pg slabs  cached allocated ctl\n");
800
	printf("---------------- -------- ------ ------ ------ ------ --------- ---\n");
801
 
802
	for (cur = slab_cache_list.next; cur != &slab_cache_list; cur = cur->next) {
759 palkovsky 803
		cache = list_get_instance(cur, slab_cache_t, link);
2052 decky 804
 
805
		printf("%-16s %8zd %6zd %6zd %6zd %6zd %9zd %-3s\n", cache->name, cache->size, (1 << cache->order), cache->objects, atomic_get(&cache->allocated_slabs), atomic_get(&cache->cached_objs), atomic_get(&cache->allocated_objs), 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*),
1780 jermar 819
			   sizeof(uintptr_t),
759 palkovsky 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),
1780 jermar 826
			   sizeof(uintptr_t),
769 palkovsky 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             */
822 palkovsky 879
void * malloc(unsigned int size, int flags)
771 palkovsky 880
{
881
	int idx;
778 palkovsky 882
 
883
	ASSERT(_slab_initialized);
1288 jermar 884
	ASSERT(size && size <= (1 << SLAB_MAX_MALLOC_W));
771 palkovsky 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
 
822 palkovsky 894
void free(void *obj)
771 palkovsky 895
{
781 palkovsky 896
	slab_t *slab;
897
 
1950 jermar 898
	if (!obj)
899
		return;
781 palkovsky 900
 
901
	slab = obj2slab(obj);
771 palkovsky 902
	_slab_free(slab->cache, obj, slab);
903
}
1702 cejka 904
 
1757 jermar 905
/** @}
1702 cejka 906
 */