xref: /freebsd/contrib/jemalloc/src/large.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
1 #define JEMALLOC_LARGE_C_
2 #include "jemalloc/internal/jemalloc_preamble.h"
3 #include "jemalloc/internal/jemalloc_internal_includes.h"
4 
5 #include "jemalloc/internal/assert.h"
6 #include "jemalloc/internal/extent_mmap.h"
7 #include "jemalloc/internal/mutex.h"
8 #include "jemalloc/internal/rtree.h"
9 #include "jemalloc/internal/util.h"
10 
11 /******************************************************************************/
12 
13 void *
14 large_malloc(tsdn_t *tsdn, arena_t *arena, size_t usize, bool zero) {
15 	assert(usize == sz_s2u(usize));
16 
17 	return large_palloc(tsdn, arena, usize, CACHELINE, zero);
18 }
19 
20 void *
21 large_palloc(tsdn_t *tsdn, arena_t *arena, size_t usize, size_t alignment,
22     bool zero) {
23 	size_t ausize;
24 	extent_t *extent;
25 	bool is_zeroed;
26 	UNUSED bool idump JEMALLOC_CC_SILENCE_INIT(false);
27 
28 	assert(!tsdn_null(tsdn) || arena != NULL);
29 
30 	ausize = sz_sa2u(usize, alignment);
31 	if (unlikely(ausize == 0 || ausize > LARGE_MAXCLASS)) {
32 		return NULL;
33 	}
34 
35 	if (config_fill && unlikely(opt_zero)) {
36 		zero = true;
37 	}
38 	/*
39 	 * Copy zero into is_zeroed and pass the copy when allocating the
40 	 * extent, so that it is possible to make correct junk/zero fill
41 	 * decisions below, even if is_zeroed ends up true when zero is false.
42 	 */
43 	is_zeroed = zero;
44 	if (likely(!tsdn_null(tsdn))) {
45 		arena = arena_choose(tsdn_tsd(tsdn), arena);
46 	}
47 	if (unlikely(arena == NULL) || (extent = arena_extent_alloc_large(tsdn,
48 	    arena, usize, alignment, &is_zeroed)) == NULL) {
49 		return NULL;
50 	}
51 
52 	/* See comments in arena_bin_slabs_full_insert(). */
53 	if (!arena_is_auto(arena)) {
54 		/* Insert extent into large. */
55 		malloc_mutex_lock(tsdn, &arena->large_mtx);
56 		extent_list_append(&arena->large, extent);
57 		malloc_mutex_unlock(tsdn, &arena->large_mtx);
58 	}
59 	if (config_prof && arena_prof_accum(tsdn, arena, usize)) {
60 		prof_idump(tsdn);
61 	}
62 
63 	if (zero) {
64 		assert(is_zeroed);
65 	} else if (config_fill && unlikely(opt_junk_alloc)) {
66 		memset(extent_addr_get(extent), JEMALLOC_ALLOC_JUNK,
67 		    extent_usize_get(extent));
68 	}
69 
70 	arena_decay_tick(tsdn, arena);
71 	return extent_addr_get(extent);
72 }
73 
74 static void
75 large_dalloc_junk_impl(void *ptr, size_t size) {
76 	memset(ptr, JEMALLOC_FREE_JUNK, size);
77 }
78 large_dalloc_junk_t *JET_MUTABLE large_dalloc_junk = large_dalloc_junk_impl;
79 
80 static void
81 large_dalloc_maybe_junk_impl(void *ptr, size_t size) {
82 	if (config_fill && have_dss && unlikely(opt_junk_free)) {
83 		/*
84 		 * Only bother junk filling if the extent isn't about to be
85 		 * unmapped.
86 		 */
87 		if (opt_retain || (have_dss && extent_in_dss(ptr))) {
88 			large_dalloc_junk(ptr, size);
89 		}
90 	}
91 }
92 large_dalloc_maybe_junk_t *JET_MUTABLE large_dalloc_maybe_junk =
93     large_dalloc_maybe_junk_impl;
94 
95 static bool
96 large_ralloc_no_move_shrink(tsdn_t *tsdn, extent_t *extent, size_t usize) {
97 	arena_t *arena = extent_arena_get(extent);
98 	size_t oldusize = extent_usize_get(extent);
99 	extent_hooks_t *extent_hooks = extent_hooks_get(arena);
100 	size_t diff = extent_size_get(extent) - (usize + sz_large_pad);
101 
102 	assert(oldusize > usize);
103 
104 	if (extent_hooks->split == NULL) {
105 		return true;
106 	}
107 
108 	/* Split excess pages. */
109 	if (diff != 0) {
110 		extent_t *trail = extent_split_wrapper(tsdn, arena,
111 		    &extent_hooks, extent, usize + sz_large_pad,
112 		    sz_size2index(usize), false, diff, NSIZES, false);
113 		if (trail == NULL) {
114 			return true;
115 		}
116 
117 		if (config_fill && unlikely(opt_junk_free)) {
118 			large_dalloc_maybe_junk(extent_addr_get(trail),
119 			    extent_size_get(trail));
120 		}
121 
122 		arena_extents_dirty_dalloc(tsdn, arena, &extent_hooks, trail);
123 	}
124 
125 	arena_extent_ralloc_large_shrink(tsdn, arena, extent, oldusize);
126 
127 	return false;
128 }
129 
130 static bool
131 large_ralloc_no_move_expand(tsdn_t *tsdn, extent_t *extent, size_t usize,
132     bool zero) {
133 	arena_t *arena = extent_arena_get(extent);
134 	size_t oldusize = extent_usize_get(extent);
135 	extent_hooks_t *extent_hooks = extent_hooks_get(arena);
136 	size_t trailsize = usize - oldusize;
137 
138 	if (extent_hooks->merge == NULL) {
139 		return true;
140 	}
141 
142 	if (config_fill && unlikely(opt_zero)) {
143 		zero = true;
144 	}
145 	/*
146 	 * Copy zero into is_zeroed_trail and pass the copy when allocating the
147 	 * extent, so that it is possible to make correct junk/zero fill
148 	 * decisions below, even if is_zeroed_trail ends up true when zero is
149 	 * false.
150 	 */
151 	bool is_zeroed_trail = zero;
152 	bool commit = true;
153 	extent_t *trail;
154 	bool new_mapping;
155 	if ((trail = extents_alloc(tsdn, arena, &extent_hooks,
156 	    &arena->extents_dirty, extent_past_get(extent), trailsize, 0,
157 	    CACHELINE, false, NSIZES, &is_zeroed_trail, &commit)) != NULL
158 	    || (trail = extents_alloc(tsdn, arena, &extent_hooks,
159 	    &arena->extents_muzzy, extent_past_get(extent), trailsize, 0,
160 	    CACHELINE, false, NSIZES, &is_zeroed_trail, &commit)) != NULL) {
161 		if (config_stats) {
162 			new_mapping = false;
163 		}
164 	} else {
165 		if ((trail = extent_alloc_wrapper(tsdn, arena, &extent_hooks,
166 		    extent_past_get(extent), trailsize, 0, CACHELINE, false,
167 		    NSIZES, &is_zeroed_trail, &commit)) == NULL) {
168 			return true;
169 		}
170 		if (config_stats) {
171 			new_mapping = true;
172 		}
173 	}
174 
175 	if (extent_merge_wrapper(tsdn, arena, &extent_hooks, extent, trail)) {
176 		extent_dalloc_wrapper(tsdn, arena, &extent_hooks, trail);
177 		return true;
178 	}
179 	rtree_ctx_t rtree_ctx_fallback;
180 	rtree_ctx_t *rtree_ctx = tsdn_rtree_ctx(tsdn, &rtree_ctx_fallback);
181 	szind_t szind = sz_size2index(usize);
182 	extent_szind_set(extent, szind);
183 	rtree_szind_slab_update(tsdn, &extents_rtree, rtree_ctx,
184 	    (uintptr_t)extent_addr_get(extent), szind, false);
185 
186 	if (config_stats && new_mapping) {
187 		arena_stats_mapped_add(tsdn, &arena->stats, trailsize);
188 	}
189 
190 	if (zero) {
191 		if (config_cache_oblivious) {
192 			/*
193 			 * Zero the trailing bytes of the original allocation's
194 			 * last page, since they are in an indeterminate state.
195 			 * There will always be trailing bytes, because ptr's
196 			 * offset from the beginning of the extent is a multiple
197 			 * of CACHELINE in [0 .. PAGE).
198 			 */
199 			void *zbase = (void *)
200 			    ((uintptr_t)extent_addr_get(extent) + oldusize);
201 			void *zpast = PAGE_ADDR2BASE((void *)((uintptr_t)zbase +
202 			    PAGE));
203 			size_t nzero = (uintptr_t)zpast - (uintptr_t)zbase;
204 			assert(nzero > 0);
205 			memset(zbase, 0, nzero);
206 		}
207 		assert(is_zeroed_trail);
208 	} else if (config_fill && unlikely(opt_junk_alloc)) {
209 		memset((void *)((uintptr_t)extent_addr_get(extent) + oldusize),
210 		    JEMALLOC_ALLOC_JUNK, usize - oldusize);
211 	}
212 
213 	arena_extent_ralloc_large_expand(tsdn, arena, extent, oldusize);
214 
215 	return false;
216 }
217 
218 bool
219 large_ralloc_no_move(tsdn_t *tsdn, extent_t *extent, size_t usize_min,
220     size_t usize_max, bool zero) {
221 	size_t oldusize = extent_usize_get(extent);
222 
223 	/* The following should have been caught by callers. */
224 	assert(usize_min > 0 && usize_max <= LARGE_MAXCLASS);
225 	/* Both allocation sizes must be large to avoid a move. */
226 	assert(oldusize >= LARGE_MINCLASS && usize_max >= LARGE_MINCLASS);
227 
228 	if (usize_max > oldusize) {
229 		/* Attempt to expand the allocation in-place. */
230 		if (!large_ralloc_no_move_expand(tsdn, extent, usize_max,
231 		    zero)) {
232 			arena_decay_tick(tsdn, extent_arena_get(extent));
233 			return false;
234 		}
235 		/* Try again, this time with usize_min. */
236 		if (usize_min < usize_max && usize_min > oldusize &&
237 		    large_ralloc_no_move_expand(tsdn, extent, usize_min,
238 		    zero)) {
239 			arena_decay_tick(tsdn, extent_arena_get(extent));
240 			return false;
241 		}
242 	}
243 
244 	/*
245 	 * Avoid moving the allocation if the existing extent size accommodates
246 	 * the new size.
247 	 */
248 	if (oldusize >= usize_min && oldusize <= usize_max) {
249 		arena_decay_tick(tsdn, extent_arena_get(extent));
250 		return false;
251 	}
252 
253 	/* Attempt to shrink the allocation in-place. */
254 	if (oldusize > usize_max) {
255 		if (!large_ralloc_no_move_shrink(tsdn, extent, usize_max)) {
256 			arena_decay_tick(tsdn, extent_arena_get(extent));
257 			return false;
258 		}
259 	}
260 	return true;
261 }
262 
263 static void *
264 large_ralloc_move_helper(tsdn_t *tsdn, arena_t *arena, size_t usize,
265     size_t alignment, bool zero) {
266 	if (alignment <= CACHELINE) {
267 		return large_malloc(tsdn, arena, usize, zero);
268 	}
269 	return large_palloc(tsdn, arena, usize, alignment, zero);
270 }
271 
272 void *
273 large_ralloc(tsdn_t *tsdn, arena_t *arena, extent_t *extent, size_t usize,
274     size_t alignment, bool zero, tcache_t *tcache) {
275 	size_t oldusize = extent_usize_get(extent);
276 
277 	/* The following should have been caught by callers. */
278 	assert(usize > 0 && usize <= LARGE_MAXCLASS);
279 	/* Both allocation sizes must be large to avoid a move. */
280 	assert(oldusize >= LARGE_MINCLASS && usize >= LARGE_MINCLASS);
281 
282 	/* Try to avoid moving the allocation. */
283 	if (!large_ralloc_no_move(tsdn, extent, usize, usize, zero)) {
284 		return extent_addr_get(extent);
285 	}
286 
287 	/*
288 	 * usize and old size are different enough that we need to use a
289 	 * different size class.  In that case, fall back to allocating new
290 	 * space and copying.
291 	 */
292 	void *ret = large_ralloc_move_helper(tsdn, arena, usize, alignment,
293 	    zero);
294 	if (ret == NULL) {
295 		return NULL;
296 	}
297 
298 	size_t copysize = (usize < oldusize) ? usize : oldusize;
299 	memcpy(ret, extent_addr_get(extent), copysize);
300 	isdalloct(tsdn, extent_addr_get(extent), oldusize, tcache, NULL, true);
301 	return ret;
302 }
303 
304 /*
305  * junked_locked indicates whether the extent's data have been junk-filled, and
306  * whether the arena's large_mtx is currently held.
307  */
308 static void
309 large_dalloc_prep_impl(tsdn_t *tsdn, arena_t *arena, extent_t *extent,
310     bool junked_locked) {
311 	if (!junked_locked) {
312 		/* See comments in arena_bin_slabs_full_insert(). */
313 		if (!arena_is_auto(arena)) {
314 			malloc_mutex_lock(tsdn, &arena->large_mtx);
315 			extent_list_remove(&arena->large, extent);
316 			malloc_mutex_unlock(tsdn, &arena->large_mtx);
317 		}
318 		large_dalloc_maybe_junk(extent_addr_get(extent),
319 		    extent_usize_get(extent));
320 	} else {
321 		malloc_mutex_assert_owner(tsdn, &arena->large_mtx);
322 		if (!arena_is_auto(arena)) {
323 			extent_list_remove(&arena->large, extent);
324 		}
325 	}
326 	arena_extent_dalloc_large_prep(tsdn, arena, extent);
327 }
328 
329 static void
330 large_dalloc_finish_impl(tsdn_t *tsdn, arena_t *arena, extent_t *extent) {
331 	extent_hooks_t *extent_hooks = EXTENT_HOOKS_INITIALIZER;
332 	arena_extents_dirty_dalloc(tsdn, arena, &extent_hooks, extent);
333 }
334 
335 void
336 large_dalloc_prep_junked_locked(tsdn_t *tsdn, extent_t *extent) {
337 	large_dalloc_prep_impl(tsdn, extent_arena_get(extent), extent, true);
338 }
339 
340 void
341 large_dalloc_finish(tsdn_t *tsdn, extent_t *extent) {
342 	large_dalloc_finish_impl(tsdn, extent_arena_get(extent), extent);
343 }
344 
345 void
346 large_dalloc(tsdn_t *tsdn, extent_t *extent) {
347 	arena_t *arena = extent_arena_get(extent);
348 	large_dalloc_prep_impl(tsdn, arena, extent, false);
349 	large_dalloc_finish_impl(tsdn, arena, extent);
350 	arena_decay_tick(tsdn, arena);
351 }
352 
353 size_t
354 large_salloc(tsdn_t *tsdn, const extent_t *extent) {
355 	return extent_usize_get(extent);
356 }
357 
358 prof_tctx_t *
359 large_prof_tctx_get(tsdn_t *tsdn, const extent_t *extent) {
360 	return extent_prof_tctx_get(extent);
361 }
362 
363 void
364 large_prof_tctx_set(tsdn_t *tsdn, extent_t *extent, prof_tctx_t *tctx) {
365 	extent_prof_tctx_set(extent, tctx);
366 }
367 
368 void
369 large_prof_tctx_reset(tsdn_t *tsdn, extent_t *extent) {
370 	large_prof_tctx_set(tsdn, extent, (prof_tctx_t *)(uintptr_t)1U);
371 }
372