tcache.h revision 3541a904d6fb949f3f0aea05418ccce7cbd4b705 
1/******************************************************************************/
2#ifdef JEMALLOC_H_TYPES
3
4typedef struct tcache_bin_info_s tcache_bin_info_t;
5typedef struct tcache_bin_s tcache_bin_t;
6typedef struct tcache_s tcache_t;
7
8/*
9 * tcache pointers close to NULL are used to encode state information that is
10 * used for two purposes: preventing thread caching on a per thread basis and
11 * cleaning up during thread shutdown.
12 */
13#define	TCACHE_STATE_DISABLED		((tcache_t *)(uintptr_t)1)
14#define	TCACHE_STATE_REINCARNATED	((tcache_t *)(uintptr_t)2)
15#define	TCACHE_STATE_PURGATORY		((tcache_t *)(uintptr_t)3)
16#define	TCACHE_STATE_MAX		TCACHE_STATE_PURGATORY
17
18/*
19 * Absolute maximum number of cache slots for each small bin in the thread
20 * cache.  This is an additional constraint beyond that imposed as: twice the
21 * number of regions per run for this size class.
22 *
23 * This constant must be an even number.
24 */
25#define	TCACHE_NSLOTS_SMALL_MAX		200
26
27/* Number of cache slots for large size classes. */
28#define	TCACHE_NSLOTS_LARGE		20
29
30/* (1U << opt_lg_tcache_max) is used to compute tcache_maxclass. */
31#define	LG_TCACHE_MAXCLASS_DEFAULT	15
32
33/*
34 * TCACHE_GC_SWEEP is the approximate number of allocation events between
35 * full GC sweeps.  Integer rounding may cause the actual number to be
36 * slightly higher, since GC is performed incrementally.
37 */
38#define	TCACHE_GC_SWEEP			8192
39
40/* Number of tcache allocation/deallocation events between incremental GCs. */
41#define	TCACHE_GC_INCR							\
42    ((TCACHE_GC_SWEEP / NBINS) + ((TCACHE_GC_SWEEP / NBINS == 0) ? 0 : 1))
43
44#endif /* JEMALLOC_H_TYPES */
45/******************************************************************************/
46#ifdef JEMALLOC_H_STRUCTS
47
48typedef enum {
49	tcache_enabled_false   = 0, /* Enable cast to/from bool. */
50	tcache_enabled_true    = 1,
51	tcache_enabled_default = 2
52} tcache_enabled_t;
53
54/*
55 * Read-only information associated with each element of tcache_t's tbins array
56 * is stored separately, mainly to reduce memory usage.
57 */
58struct tcache_bin_info_s {
59	unsigned	ncached_max;	/* Upper limit on ncached. */
60};
61
62struct tcache_bin_s {
63	tcache_bin_stats_t tstats;
64	int		low_water;	/* Min # cached since last GC. */
65	unsigned	lg_fill_div;	/* Fill (ncached_max >> lg_fill_div). */
66	unsigned	ncached;	/* # of cached objects. */
67	void		**avail;	/* Stack of available objects. */
68};
69
70struct tcache_s {
71	ql_elm(tcache_t) link;		/* Used for aggregating stats. */
72	uint64_t	prof_accumbytes;/* Cleared after arena_prof_accum() */
73	arena_t		*arena;		/* This thread's arena. */
74	unsigned	ev_cnt;		/* Event count since incremental GC. */
75	unsigned	next_gc_bin;	/* Next bin to GC. */
76	tcache_bin_t	tbins[1];	/* Dynamically sized. */
77	/*
78	 * The pointer stacks associated with tbins follow as a contiguous
79	 * array.  During tcache initialization, the avail pointer in each
80	 * element of tbins is initialized to point to the proper offset within
81	 * this array.
82	 */
83};
84
85#endif /* JEMALLOC_H_STRUCTS */
86/******************************************************************************/
87#ifdef JEMALLOC_H_EXTERNS
88
89extern bool	opt_tcache;
90extern ssize_t	opt_lg_tcache_max;
91
92extern tcache_bin_info_t	*tcache_bin_info;
93
94/*
95 * Number of tcache bins.  There are NBINS small-object bins, plus 0 or more
96 * large-object bins.
97 */
98extern size_t			nhbins;
99
100/* Maximum cached size class. */
101extern size_t			tcache_maxclass;
102
103size_t	tcache_salloc(const void *ptr);
104void	tcache_event_hard(tcache_t *tcache);
105void	*tcache_alloc_small_hard(tcache_t *tcache, tcache_bin_t *tbin,
106    size_t binind);
107void	tcache_bin_flush_small(tcache_bin_t *tbin, size_t binind, unsigned rem,
108    tcache_t *tcache);
109void	tcache_bin_flush_large(tcache_bin_t *tbin, size_t binind, unsigned rem,
110    tcache_t *tcache);
111void	tcache_arena_associate(tcache_t *tcache, arena_t *arena);
112void	tcache_arena_dissociate(tcache_t *tcache);
113tcache_t *tcache_get_hard(tcache_t *tcache, bool create);
114tcache_t *tcache_create(arena_t *arena);
115void	tcache_destroy(tcache_t *tcache);
116void	tcache_thread_cleanup(void *arg);
117void	tcache_stats_merge(tcache_t *tcache, arena_t *arena);
118bool	tcache_boot0(void);
119bool	tcache_boot1(void);
120
121#endif /* JEMALLOC_H_EXTERNS */
122/******************************************************************************/
123#ifdef JEMALLOC_H_INLINES
124
125#ifndef JEMALLOC_ENABLE_INLINE
126malloc_tsd_protos(JEMALLOC_ATTR(unused), tcache, tcache_t *)
127malloc_tsd_protos(JEMALLOC_ATTR(unused), tcache_enabled, tcache_enabled_t)
128
129void	tcache_event(tcache_t *tcache);
130void	tcache_flush(void);
131bool	tcache_enabled_get(void);
132tcache_t *tcache_get(bool create);
133void	tcache_enabled_set(bool enabled);
134void	*tcache_alloc_easy(tcache_bin_t *tbin);
135void	*tcache_alloc_small(tcache_t *tcache, size_t size, bool zero);
136void	*tcache_alloc_large(tcache_t *tcache, size_t size, bool zero);
137void	tcache_dalloc_small(tcache_t *tcache, void *ptr, size_t binind);
138void	tcache_dalloc_large(tcache_t *tcache, void *ptr, size_t size);
139#endif
140
141#if (defined(JEMALLOC_ENABLE_INLINE) || defined(JEMALLOC_TCACHE_C_))
142/* Map of thread-specific caches. */
143malloc_tsd_externs(tcache, tcache_t *)
144malloc_tsd_funcs(JEMALLOC_ALWAYS_INLINE, tcache, tcache_t *, NULL,
145    tcache_thread_cleanup)
146/* Per thread flag that allows thread caches to be disabled. */
147malloc_tsd_externs(tcache_enabled, tcache_enabled_t)
148malloc_tsd_funcs(JEMALLOC_ALWAYS_INLINE, tcache_enabled, tcache_enabled_t,
149    tcache_enabled_default, malloc_tsd_no_cleanup)
150
151JEMALLOC_INLINE void
152tcache_flush(void)
153{
154	tcache_t *tcache;
155
156	cassert(config_tcache);
157
158	tcache = *tcache_tsd_get();
159	if ((uintptr_t)tcache <= (uintptr_t)TCACHE_STATE_MAX)
160		return;
161	tcache_destroy(tcache);
162	tcache = NULL;
163	tcache_tsd_set(&tcache);
164}
165
166JEMALLOC_INLINE bool
167tcache_enabled_get(void)
168{
169	tcache_enabled_t tcache_enabled;
170
171	cassert(config_tcache);
172
173	tcache_enabled = *tcache_enabled_tsd_get();
174	if (tcache_enabled == tcache_enabled_default) {
175		tcache_enabled = (tcache_enabled_t)opt_tcache;
176		tcache_enabled_tsd_set(&tcache_enabled);
177	}
178
179	return ((bool)tcache_enabled);
180}
181
182JEMALLOC_INLINE void
183tcache_enabled_set(bool enabled)
184{
185	tcache_enabled_t tcache_enabled;
186	tcache_t *tcache;
187
188	cassert(config_tcache);
189
190	tcache_enabled = (tcache_enabled_t)enabled;
191	tcache_enabled_tsd_set(&tcache_enabled);
192	tcache = *tcache_tsd_get();
193	if (enabled) {
194		if (tcache == TCACHE_STATE_DISABLED) {
195			tcache = NULL;
196			tcache_tsd_set(&tcache);
197		}
198	} else /* disabled */ {
199		if (tcache > TCACHE_STATE_MAX) {
200			tcache_destroy(tcache);
201			tcache = NULL;
202		}
203		if (tcache == NULL) {
204			tcache = TCACHE_STATE_DISABLED;
205			tcache_tsd_set(&tcache);
206		}
207	}
208}
209
210JEMALLOC_ALWAYS_INLINE tcache_t *
211tcache_get(bool create)
212{
213	tcache_t *tcache;
214
215	if (config_tcache == false)
216		return (NULL);
217	if (config_lazy_lock && isthreaded == false)
218		return (NULL);
219
220	tcache = *tcache_tsd_get();
221	if ((uintptr_t)tcache <= (uintptr_t)TCACHE_STATE_MAX) {
222		if (tcache == TCACHE_STATE_DISABLED)
223			return (NULL);
224		tcache = tcache_get_hard(tcache, create);
225	}
226
227	return (tcache);
228}
229
230JEMALLOC_ALWAYS_INLINE void
231tcache_event(tcache_t *tcache)
232{
233
234	if (TCACHE_GC_INCR == 0)
235		return;
236
237	tcache->ev_cnt++;
238	assert(tcache->ev_cnt <= TCACHE_GC_INCR);
239	if (tcache->ev_cnt == TCACHE_GC_INCR)
240		tcache_event_hard(tcache);
241}
242
243JEMALLOC_ALWAYS_INLINE void *
244tcache_alloc_easy(tcache_bin_t *tbin)
245{
246	void *ret;
247
248	if (tbin->ncached == 0) {
249		tbin->low_water = -1;
250		return (NULL);
251	}
252	tbin->ncached--;
253	if ((int)tbin->ncached < tbin->low_water)
254		tbin->low_water = tbin->ncached;
255	ret = tbin->avail[tbin->ncached];
256	return (ret);
257}
258
259JEMALLOC_ALWAYS_INLINE void *
260tcache_alloc_small(tcache_t *tcache, size_t size, bool zero)
261{
262	void *ret;
263	size_t binind;
264	tcache_bin_t *tbin;
265
266	binind = small_size2bin(size);
267	assert(binind < NBINS);
268	tbin = &tcache->tbins[binind];
269	size = small_bin2size(binind);
270	ret = tcache_alloc_easy(tbin);
271	if (ret == NULL) {
272		ret = tcache_alloc_small_hard(tcache, tbin, binind);
273		if (ret == NULL)
274			return (NULL);
275	}
276	assert(tcache_salloc(ret) == size);
277
278	if (zero == false) {
279		if (config_fill) {
280			if (opt_junk) {
281				arena_alloc_junk_small(ret,
282				    &arena_bin_info[binind], false);
283			} else if (opt_zero)
284				memset(ret, 0, size);
285		}
286	} else {
287		if (config_fill && opt_junk) {
288			arena_alloc_junk_small(ret, &arena_bin_info[binind],
289			    true);
290		}
291		memset(ret, 0, size);
292	}
293
294	if (config_stats)
295		tbin->tstats.nrequests++;
296	if (config_prof)
297		tcache->prof_accumbytes += size;
298	tcache_event(tcache);
299	return (ret);
300}
301
302JEMALLOC_ALWAYS_INLINE void *
303tcache_alloc_large(tcache_t *tcache, size_t size, bool zero)
304{
305	void *ret;
306	size_t binind;
307	tcache_bin_t *tbin;
308
309	size = PAGE_CEILING(size);
310	assert(size <= tcache_maxclass);
311	binind = NBINS + (size >> LG_PAGE) - 1;
312	assert(binind < nhbins);
313	tbin = &tcache->tbins[binind];
314	ret = tcache_alloc_easy(tbin);
315	if (ret == NULL) {
316		/*
317		 * Only allocate one large object at a time, because it's quite
318		 * expensive to create one and not use it.
319		 */
320		ret = arena_malloc_large(tcache->arena, size, zero);
321		if (ret == NULL)
322			return (NULL);
323	} else {
324		if (config_prof && size == PAGE) {
325			arena_chunk_t *chunk =
326			    (arena_chunk_t *)CHUNK_ADDR2BASE(ret);
327			size_t pageind = (((uintptr_t)ret - (uintptr_t)chunk) >>
328			    LG_PAGE);
329			arena_mapbits_large_binind_set(chunk, pageind,
330			    BININD_INVALID);
331		}
332		if (zero == false) {
333			if (config_fill) {
334				if (opt_junk)
335					memset(ret, 0xa5, size);
336				else if (opt_zero)
337					memset(ret, 0, size);
338			}
339		} else
340			memset(ret, 0, size);
341
342		if (config_stats)
343			tbin->tstats.nrequests++;
344		if (config_prof)
345			tcache->prof_accumbytes += size;
346	}
347
348	tcache_event(tcache);
349	return (ret);
350}
351
352JEMALLOC_ALWAYS_INLINE void
353tcache_dalloc_small(tcache_t *tcache, void *ptr, size_t binind)
354{
355	tcache_bin_t *tbin;
356	tcache_bin_info_t *tbin_info;
357
358	assert(tcache_salloc(ptr) <= SMALL_MAXCLASS);
359
360	if (config_fill && opt_junk)
361		arena_dalloc_junk_small(ptr, &arena_bin_info[binind]);
362
363	tbin = &tcache->tbins[binind];
364	tbin_info = &tcache_bin_info[binind];
365	if (tbin->ncached == tbin_info->ncached_max) {
366		tcache_bin_flush_small(tbin, binind, (tbin_info->ncached_max >>
367		    1), tcache);
368	}
369	assert(tbin->ncached < tbin_info->ncached_max);
370	tbin->avail[tbin->ncached] = ptr;
371	tbin->ncached++;
372
373	tcache_event(tcache);
374}
375
376JEMALLOC_ALWAYS_INLINE void
377tcache_dalloc_large(tcache_t *tcache, void *ptr, size_t size)
378{
379	size_t binind;
380	tcache_bin_t *tbin;
381	tcache_bin_info_t *tbin_info;
382
383	assert((size & PAGE_MASK) == 0);
384	assert(tcache_salloc(ptr) > SMALL_MAXCLASS);
385	assert(tcache_salloc(ptr) <= tcache_maxclass);
386
387	binind = NBINS + (size >> LG_PAGE) - 1;
388
389	if (config_fill && opt_junk)
390		memset(ptr, 0x5a, size);
391
392	tbin = &tcache->tbins[binind];
393	tbin_info = &tcache_bin_info[binind];
394	if (tbin->ncached == tbin_info->ncached_max) {
395		tcache_bin_flush_large(tbin, binind, (tbin_info->ncached_max >>
396		    1), tcache);
397	}
398	assert(tbin->ncached < tbin_info->ncached_max);
399	tbin->avail[tbin->ncached] = ptr;
400	tbin->ncached++;
401
402	tcache_event(tcache);
403}
404#endif
405
406#endif /* JEMALLOC_H_INLINES */
407/******************************************************************************/
408