tcache.c revision 1dcb4f86b23a5760f5a717ace716360b63b33fad 
1#define	JEMALLOC_TCACHE_C_
2#include "jemalloc/internal/jemalloc_internal.h"
3#ifdef JEMALLOC_TCACHE
4/******************************************************************************/
5/* Data. */
6
7bool	opt_tcache = true;
8ssize_t	opt_lg_tcache_max = LG_TCACHE_MAXCLASS_DEFAULT;
9ssize_t	opt_lg_tcache_gc_sweep = LG_TCACHE_GC_SWEEP_DEFAULT;
10
11tcache_bin_info_t	*tcache_bin_info;
12static unsigned		stack_nelms; /* Total stack elms per tcache. */
13
14/* Map of thread-specific caches. */
15#ifndef NO_TLS
16__thread tcache_t	*tcache_tls JEMALLOC_ATTR(tls_model("initial-exec"));
17#endif
18
19/*
20 * Same contents as tcache, but initialized such that the TSD destructor is
21 * called when a thread exits, so that the cache can be cleaned up.
22 */
23pthread_key_t		tcache_tsd;
24
25size_t				nhbins;
26size_t				tcache_maxclass;
27unsigned			tcache_gc_incr;
28
29/******************************************************************************/
30/* Function prototypes for non-inline static functions. */
31
32static void	tcache_thread_cleanup(void *arg);
33
34/******************************************************************************/
35
36void *
37tcache_alloc_small_hard(tcache_t *tcache, tcache_bin_t *tbin, size_t binind)
38{
39	void *ret;
40
41	arena_tcache_fill_small(tcache->arena, tbin, binind
42#ifdef JEMALLOC_PROF
43	    , tcache->prof_accumbytes
44#endif
45	    );
46#ifdef JEMALLOC_PROF
47	tcache->prof_accumbytes = 0;
48#endif
49	ret = tcache_alloc_easy(tbin);
50
51	return (ret);
52}
53
54void
55tcache_bin_flush_small(tcache_bin_t *tbin, size_t binind, unsigned rem
56#if (defined(JEMALLOC_STATS) || defined(JEMALLOC_PROF))
57    , tcache_t *tcache
58#endif
59    )
60{
61	void *ptr;
62	unsigned i, nflush, ndeferred;
63#ifdef JEMALLOC_STATS
64	bool merged_stats = false;
65#endif
66
67	assert(binind < nbins);
68	assert(rem <= tbin->ncached);
69
70	for (nflush = tbin->ncached - rem; nflush > 0; nflush = ndeferred) {
71		/* Lock the arena bin associated with the first object. */
72		arena_chunk_t *chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(
73		    tbin->avail[0]);
74		arena_t *arena = chunk->arena;
75		arena_bin_t *bin = &arena->bins[binind];
76
77#ifdef JEMALLOC_PROF
78		if (arena == tcache->arena) {
79			malloc_mutex_lock(&arena->lock);
80			arena_prof_accum(arena, tcache->prof_accumbytes);
81			malloc_mutex_unlock(&arena->lock);
82			tcache->prof_accumbytes = 0;
83		}
84#endif
85
86		malloc_mutex_lock(&bin->lock);
87#ifdef JEMALLOC_STATS
88		if (arena == tcache->arena) {
89			assert(merged_stats == false);
90			merged_stats = true;
91			bin->stats.nflushes++;
92			bin->stats.nrequests += tbin->tstats.nrequests;
93			tbin->tstats.nrequests = 0;
94		}
95#endif
96		ndeferred = 0;
97		for (i = 0; i < nflush; i++) {
98			ptr = tbin->avail[i];
99			assert(ptr != NULL);
100			chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
101			if (chunk->arena == arena) {
102				size_t pageind = ((uintptr_t)ptr -
103				    (uintptr_t)chunk) >> PAGE_SHIFT;
104				arena_chunk_map_t *mapelm =
105				    &chunk->map[pageind-map_bias];
106				arena_dalloc_bin(arena, chunk, ptr, mapelm);
107			} else {
108				/*
109				 * This object was allocated via a different
110				 * arena bin than the one that is currently
111				 * locked.  Stash the object, so that it can be
112				 * handled in a future pass.
113				 */
114				tbin->avail[ndeferred] = ptr;
115				ndeferred++;
116			}
117		}
118		malloc_mutex_unlock(&bin->lock);
119	}
120#ifdef JEMALLOC_STATS
121	if (merged_stats == false) {
122		/*
123		 * The flush loop didn't happen to flush to this thread's
124		 * arena, so the stats didn't get merged.  Manually do so now.
125		 */
126		arena_bin_t *bin = &tcache->arena->bins[binind];
127		malloc_mutex_lock(&bin->lock);
128		bin->stats.nflushes++;
129		bin->stats.nrequests += tbin->tstats.nrequests;
130		tbin->tstats.nrequests = 0;
131		malloc_mutex_unlock(&bin->lock);
132	}
133#endif
134
135	memmove(tbin->avail, &tbin->avail[tbin->ncached - rem],
136	    rem * sizeof(void *));
137	tbin->ncached = rem;
138	if ((int)tbin->ncached < tbin->low_water)
139		tbin->low_water = tbin->ncached;
140}
141
142void
143tcache_bin_flush_large(tcache_bin_t *tbin, size_t binind, unsigned rem
144#if (defined(JEMALLOC_STATS) || defined(JEMALLOC_PROF))
145    , tcache_t *tcache
146#endif
147    )
148{
149	void *ptr;
150	unsigned i, nflush, ndeferred;
151#ifdef JEMALLOC_STATS
152	bool merged_stats = false;
153#endif
154
155	assert(binind < nhbins);
156	assert(rem <= tbin->ncached);
157
158	for (nflush = tbin->ncached - rem; nflush > 0; nflush = ndeferred) {
159		/* Lock the arena associated with the first object. */
160		arena_chunk_t *chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(
161		    tbin->avail[0]);
162		arena_t *arena = chunk->arena;
163
164		malloc_mutex_lock(&arena->lock);
165#if (defined(JEMALLOC_PROF) || defined(JEMALLOC_STATS))
166		if (arena == tcache->arena) {
167#endif
168#ifdef JEMALLOC_PROF
169			arena_prof_accum(arena, tcache->prof_accumbytes);
170			tcache->prof_accumbytes = 0;
171#endif
172#ifdef JEMALLOC_STATS
173			merged_stats = true;
174			arena->stats.nrequests_large += tbin->tstats.nrequests;
175			arena->stats.lstats[binind - nbins].nrequests +=
176			    tbin->tstats.nrequests;
177			tbin->tstats.nrequests = 0;
178#endif
179#if (defined(JEMALLOC_PROF) || defined(JEMALLOC_STATS))
180		}
181#endif
182		ndeferred = 0;
183		for (i = 0; i < nflush; i++) {
184			ptr = tbin->avail[i];
185			assert(ptr != NULL);
186			chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
187			if (chunk->arena == arena)
188				arena_dalloc_large(arena, chunk, ptr);
189			else {
190				/*
191				 * This object was allocated via a different
192				 * arena than the one that is currently locked.
193				 * Stash the object, so that it can be handled
194				 * in a future pass.
195				 */
196				tbin->avail[ndeferred] = ptr;
197				ndeferred++;
198			}
199		}
200		malloc_mutex_unlock(&arena->lock);
201	}
202#ifdef JEMALLOC_STATS
203	if (merged_stats == false) {
204		/*
205		 * The flush loop didn't happen to flush to this thread's
206		 * arena, so the stats didn't get merged.  Manually do so now.
207		 */
208		arena_t *arena = tcache->arena;
209		malloc_mutex_lock(&arena->lock);
210		arena->stats.nrequests_large += tbin->tstats.nrequests;
211		arena->stats.lstats[binind - nbins].nrequests +=
212		    tbin->tstats.nrequests;
213		tbin->tstats.nrequests = 0;
214		malloc_mutex_unlock(&arena->lock);
215	}
216#endif
217
218	memmove(tbin->avail, &tbin->avail[tbin->ncached - rem],
219	    rem * sizeof(void *));
220	tbin->ncached = rem;
221	if ((int)tbin->ncached < tbin->low_water)
222		tbin->low_water = tbin->ncached;
223}
224
225tcache_t *
226tcache_create(arena_t *arena)
227{
228	tcache_t *tcache;
229	size_t size, stack_offset;
230	unsigned i;
231
232	size = offsetof(tcache_t, tbins) + (sizeof(tcache_bin_t) * nhbins);
233	/* Naturally align the pointer stacks. */
234	size = PTR_CEILING(size);
235	stack_offset = size;
236	size += stack_nelms * sizeof(void *);
237	/*
238	 * Round up to the nearest multiple of the cacheline size, in order to
239	 * avoid the possibility of false cacheline sharing.
240	 *
241	 * That this works relies on the same logic as in ipalloc(), but we
242	 * cannot directly call ipalloc() here due to tcache bootstrapping
243	 * issues.
244	 */
245	size = (size + CACHELINE_MASK) & (-CACHELINE);
246
247	if (size <= small_maxclass)
248		tcache = (tcache_t *)arena_malloc_small(arena, size, true);
249	else if (size <= tcache_maxclass)
250		tcache = (tcache_t *)arena_malloc_large(arena, size, true);
251	else
252		tcache = (tcache_t *)icalloc(size);
253
254	if (tcache == NULL)
255		return (NULL);
256
257#ifdef JEMALLOC_STATS
258	/* Link into list of extant tcaches. */
259	malloc_mutex_lock(&arena->lock);
260	ql_elm_new(tcache, link);
261	ql_tail_insert(&arena->tcache_ql, tcache, link);
262	malloc_mutex_unlock(&arena->lock);
263#endif
264
265	tcache->arena = arena;
266	assert((TCACHE_NSLOTS_SMALL_MAX & 1U) == 0);
267	for (i = 0; i < nhbins; i++) {
268		tcache->tbins[i].lg_fill_div = 1;
269		tcache->tbins[i].avail = (void **)((uintptr_t)tcache +
270		    (uintptr_t)stack_offset);
271		stack_offset += tcache_bin_info[i].ncached_max * sizeof(void *);
272	}
273
274	TCACHE_SET(tcache);
275
276	return (tcache);
277}
278
279void
280tcache_destroy(tcache_t *tcache)
281{
282	unsigned i;
283	size_t tcache_size;
284
285#ifdef JEMALLOC_STATS
286	/* Unlink from list of extant tcaches. */
287	malloc_mutex_lock(&tcache->arena->lock);
288	ql_remove(&tcache->arena->tcache_ql, tcache, link);
289	malloc_mutex_unlock(&tcache->arena->lock);
290	tcache_stats_merge(tcache, tcache->arena);
291#endif
292
293	for (i = 0; i < nbins; i++) {
294		tcache_bin_t *tbin = &tcache->tbins[i];
295		tcache_bin_flush_small(tbin, i, 0
296#if (defined(JEMALLOC_STATS) || defined(JEMALLOC_PROF))
297		    , tcache
298#endif
299		    );
300
301#ifdef JEMALLOC_STATS
302		if (tbin->tstats.nrequests != 0) {
303			arena_t *arena = tcache->arena;
304			arena_bin_t *bin = &arena->bins[i];
305			malloc_mutex_lock(&bin->lock);
306			bin->stats.nrequests += tbin->tstats.nrequests;
307			malloc_mutex_unlock(&bin->lock);
308		}
309#endif
310	}
311
312	for (; i < nhbins; i++) {
313		tcache_bin_t *tbin = &tcache->tbins[i];
314		tcache_bin_flush_large(tbin, i, 0
315#if (defined(JEMALLOC_STATS) || defined(JEMALLOC_PROF))
316		    , tcache
317#endif
318		    );
319
320#ifdef JEMALLOC_STATS
321		if (tbin->tstats.nrequests != 0) {
322			arena_t *arena = tcache->arena;
323			malloc_mutex_lock(&arena->lock);
324			arena->stats.nrequests_large += tbin->tstats.nrequests;
325			arena->stats.lstats[i - nbins].nrequests +=
326			    tbin->tstats.nrequests;
327			malloc_mutex_unlock(&arena->lock);
328		}
329#endif
330	}
331
332#ifdef JEMALLOC_PROF
333	if (tcache->prof_accumbytes > 0) {
334		malloc_mutex_lock(&tcache->arena->lock);
335		arena_prof_accum(tcache->arena, tcache->prof_accumbytes);
336		malloc_mutex_unlock(&tcache->arena->lock);
337	}
338#endif
339
340	tcache_size = arena_salloc(tcache);
341	if (tcache_size <= small_maxclass) {
342		arena_chunk_t *chunk = CHUNK_ADDR2BASE(tcache);
343		arena_t *arena = chunk->arena;
344		size_t pageind = ((uintptr_t)tcache - (uintptr_t)chunk) >>
345		    PAGE_SHIFT;
346		arena_chunk_map_t *mapelm = &chunk->map[pageind-map_bias];
347		arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
348		    (uintptr_t)((pageind - (mapelm->bits >> PAGE_SHIFT)) <<
349		    PAGE_SHIFT));
350		arena_bin_t *bin = run->bin;
351
352		malloc_mutex_lock(&bin->lock);
353		arena_dalloc_bin(arena, chunk, tcache, mapelm);
354		malloc_mutex_unlock(&bin->lock);
355	} else if (tcache_size <= tcache_maxclass) {
356		arena_chunk_t *chunk = CHUNK_ADDR2BASE(tcache);
357		arena_t *arena = chunk->arena;
358
359		malloc_mutex_lock(&arena->lock);
360		arena_dalloc_large(arena, chunk, tcache);
361		malloc_mutex_unlock(&arena->lock);
362	} else
363		idalloc(tcache);
364}
365
366static void
367tcache_thread_cleanup(void *arg)
368{
369	tcache_t *tcache = (tcache_t *)arg;
370
371	if (tcache == (void *)(uintptr_t)1) {
372		/*
373		 * The previous time this destructor was called, we set the key
374		 * to 1 so that other destructors wouldn't cause re-creation of
375		 * the tcache.  This time, do nothing, so that the destructor
376		 * will not be called again.
377		 */
378	} else if (tcache == (void *)(uintptr_t)2) {
379		/*
380		 * Another destructor called an allocator function after this
381		 * destructor was called.  Reset tcache to 1 in order to
382		 * receive another callback.
383		 */
384		TCACHE_SET((uintptr_t)1);
385	} else if (tcache != NULL) {
386		assert(tcache != (void *)(uintptr_t)1);
387		tcache_destroy(tcache);
388		TCACHE_SET((uintptr_t)1);
389	}
390}
391
392#ifdef JEMALLOC_STATS
393void
394tcache_stats_merge(tcache_t *tcache, arena_t *arena)
395{
396	unsigned i;
397
398	/* Merge and reset tcache stats. */
399	for (i = 0; i < nbins; i++) {
400		arena_bin_t *bin = &arena->bins[i];
401		tcache_bin_t *tbin = &tcache->tbins[i];
402		malloc_mutex_lock(&bin->lock);
403		bin->stats.nrequests += tbin->tstats.nrequests;
404		malloc_mutex_unlock(&bin->lock);
405		tbin->tstats.nrequests = 0;
406	}
407
408	for (; i < nhbins; i++) {
409		malloc_large_stats_t *lstats = &arena->stats.lstats[i - nbins];
410		tcache_bin_t *tbin = &tcache->tbins[i];
411		arena->stats.nrequests_large += tbin->tstats.nrequests;
412		lstats->nrequests += tbin->tstats.nrequests;
413		tbin->tstats.nrequests = 0;
414	}
415}
416#endif
417
418bool
419tcache_boot(void)
420{
421
422	if (opt_tcache) {
423		unsigned i;
424
425		/*
426		 * If necessary, clamp opt_lg_tcache_max, now that
427		 * small_maxclass and arena_maxclass are known.
428		 */
429		if (opt_lg_tcache_max < 0 || (1U <<
430		    opt_lg_tcache_max) < small_maxclass)
431			tcache_maxclass = small_maxclass;
432		else if ((1U << opt_lg_tcache_max) > arena_maxclass)
433			tcache_maxclass = arena_maxclass;
434		else
435			tcache_maxclass = (1U << opt_lg_tcache_max);
436
437		nhbins = nbins + (tcache_maxclass >> PAGE_SHIFT);
438
439		/* Initialize tcache_bin_info. */
440		tcache_bin_info = (tcache_bin_info_t *)base_alloc(nhbins *
441		    sizeof(tcache_bin_info_t));
442		if (tcache_bin_info == NULL)
443			return (true);
444		stack_nelms = 0;
445		for (i = 0; i < nbins; i++) {
446			if ((arena_bin_info[i].nregs << 1) <=
447			    TCACHE_NSLOTS_SMALL_MAX) {
448				tcache_bin_info[i].ncached_max =
449				    (arena_bin_info[i].nregs << 1);
450			} else {
451				tcache_bin_info[i].ncached_max =
452				    TCACHE_NSLOTS_SMALL_MAX;
453			}
454			stack_nelms += tcache_bin_info[i].ncached_max;
455		}
456		for (; i < nhbins; i++) {
457			tcache_bin_info[i].ncached_max = TCACHE_NSLOTS_LARGE;
458			stack_nelms += tcache_bin_info[i].ncached_max;
459		}
460
461		/* Compute incremental GC event threshold. */
462		if (opt_lg_tcache_gc_sweep >= 0) {
463			tcache_gc_incr = ((1U << opt_lg_tcache_gc_sweep) /
464			    nbins) + (((1U << opt_lg_tcache_gc_sweep) % nbins ==
465			    0) ? 0 : 1);
466		} else
467			tcache_gc_incr = 0;
468
469		if (pthread_key_create(&tcache_tsd, tcache_thread_cleanup) !=
470		    0) {
471			malloc_write(
472			    "<jemalloc>: Error in pthread_key_create()\n");
473			abort();
474		}
475	}
476
477	return (false);
478}
479/******************************************************************************/
480#endif /* JEMALLOC_TCACHE */
481