1/*
2 * Copyright (c) 2012-2013 Apple Inc. All rights reserved.
3 *
4 * @APPLE_APACHE_LICENSE_HEADER_START@
5 *
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 *     http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 *
18 * @APPLE_APACHE_LICENSE_HEADER_END@
19 */
20
21/*
22 * IMPORTANT: This header file describes INTERNAL interfaces to libdispatch
23 * which are subject to change in future releases of Mac OS X. Any applications
24 * relying on these interfaces WILL break.
25 */
26
27#ifndef __DISPATCH_ALLOCATOR_INTERNAL__
28#define __DISPATCH_ALLOCATOR_INTERNAL__
29
30#ifndef DISPATCH_ALLOCATOR
31#if TARGET_OS_MAC && (defined(__LP64__) || TARGET_OS_EMBEDDED)
32#define DISPATCH_ALLOCATOR 1
33#endif
34#endif
35
36#if TARGET_IPHONE_SIMULATOR && IPHONE_SIMULATOR_HOST_MIN_VERSION_REQUIRED < 1090
37#undef DISPATCH_USE_NANOZONE
38#define DISPATCH_USE_NANOZONE 0
39#endif
40#ifndef DISPATCH_USE_NANOZONE
41#if TARGET_OS_MAC && defined(__LP64__) && \
42		(__MAC_OS_X_VERSION_MIN_REQUIRED >= 1090 || \
43		__IPHONE_OS_VERSION_MIN_REQUIRED >= 70000)
44#define DISPATCH_USE_NANOZONE 1
45#endif
46#endif
47
48#ifndef DISPATCH_USE_MALLOCZONE
49#if (TARGET_OS_MAC && !DISPATCH_USE_NANOZONE) || \
50		(!TARGET_OS_MAC && HAVE_MALLOC_CREATE_ZONE)
51#define DISPATCH_USE_MALLOCZONE 1
52#endif
53#endif
54
55#ifndef DISPATCH_CONTINUATION_MALLOC
56#if DISPATCH_USE_NANOZONE || !DISPATCH_ALLOCATOR
57#define DISPATCH_CONTINUATION_MALLOC 1
58#endif
59#endif
60
61#if !DISPATCH_ALLOCATOR && !DISPATCH_CONTINUATION_MALLOC
62#error Invalid allocator configuration
63#endif
64
65#if DISPATCH_ALLOCATOR && DISPATCH_CONTINUATION_MALLOC
66#define DISPATCH_ALLOC_NOINLINE DISPATCH_NOINLINE
67#else
68#define DISPATCH_ALLOC_NOINLINE
69#endif
70
71#pragma mark -
72#pragma mark DISPATCH_ALLOCATOR
73
74#if DISPATCH_ALLOCATOR
75
76// Configuration here!
77#define NUM_CPU _dispatch_hw_config.cc_max_logical
78#define MAGAZINES_PER_HEAP (NUM_CPU)
79
80// Do you care about compaction or performance?
81#if TARGET_OS_EMBEDDED
82#define PACK_FIRST_PAGE_WITH_CONTINUATIONS 1
83#else
84#define PACK_FIRST_PAGE_WITH_CONTINUATIONS 0
85#endif
86
87#if TARGET_OS_EMBEDDED
88#define PAGES_PER_MAGAZINE 64
89#else
90#define PAGES_PER_MAGAZINE 512
91#endif
92
93// Use the largest type your platform is comfortable doing atomic ops with.
94#if defined(__x86_64__) // TODO: rdar://11477843
95typedef unsigned long bitmap_t;
96#define BYTES_PER_BITMAP 8
97#else
98typedef uint32_t bitmap_t;
99#define BYTES_PER_BITMAP 4
100#endif
101
102#define BITMAP_C(v) ((bitmap_t)(v))
103#define BITMAP_ALL_ONES (~BITMAP_C(0))
104
105// Stop configuring.
106
107#define CONTINUATIONS_PER_BITMAP (BYTES_PER_BITMAP * 8)
108#define BITMAPS_PER_SUPERMAP (BYTES_PER_SUPERMAP * 8)
109
110#define BYTES_PER_MAGAZINE (PAGES_PER_MAGAZINE * PAGE_SIZE)
111#define CONSUMED_BYTES_PER_BITMAP (BYTES_PER_BITMAP + \
112		(DISPATCH_CONTINUATION_SIZE * CONTINUATIONS_PER_BITMAP))
113
114#define BYTES_PER_SUPERMAP BYTES_PER_BITMAP
115#define CONSUMED_BYTES_PER_SUPERMAP (BYTES_PER_SUPERMAP + \
116		(BITMAPS_PER_SUPERMAP * CONSUMED_BYTES_PER_BITMAP))
117
118#define BYTES_PER_HEAP (BYTES_PER_MAGAZINE * MAGAZINES_PER_HEAP)
119
120#define BYTES_PER_PAGE PAGE_SIZE
121#define CONTINUATIONS_PER_PAGE (BYTES_PER_PAGE / DISPATCH_CONTINUATION_SIZE)
122#define BITMAPS_PER_PAGE (CONTINUATIONS_PER_PAGE / CONTINUATIONS_PER_BITMAP)
123
124// Assumption: metadata will be only in the first page.
125#define SUPERMAPS_PER_MAGAZINE ((BYTES_PER_MAGAZINE - BYTES_PER_PAGE) / \
126		CONSUMED_BYTES_PER_SUPERMAP)
127#define BITMAPS_PER_MAGAZINE (SUPERMAPS_PER_MAGAZINE * BITMAPS_PER_SUPERMAP)
128#define CONTINUATIONS_PER_MAGAZINE \
129		(BITMAPS_PER_MAGAZINE * CONTINUATIONS_PER_BITMAP)
130
131#define HEAP_MASK (~(uintptr_t)(BYTES_PER_HEAP - 1))
132#define MAGAZINE_MASK (~(uintptr_t)(BYTES_PER_MAGAZINE - 1))
133
134#define PADDING_TO_CONTINUATION_SIZE(x) (ROUND_UP_TO_CONTINUATION_SIZE(x) - (x))
135
136#if defined(__LP64__)
137#define SIZEOF_HEADER 16
138#else
139#define SIZEOF_HEADER 8
140#endif
141
142#define SIZEOF_SUPERMAPS (BYTES_PER_SUPERMAP * SUPERMAPS_PER_MAGAZINE)
143#define SIZEOF_MAPS (BYTES_PER_BITMAP * BITMAPS_PER_SUPERMAP * \
144		SUPERMAPS_PER_MAGAZINE)
145
146// header is expected to end on supermap's required alignment
147#define HEADER_TO_SUPERMAPS_PADDING 0
148#define SUPERMAPS_TO_MAPS_PADDING (PADDING_TO_CONTINUATION_SIZE( \
149		SIZEOF_SUPERMAPS + HEADER_TO_SUPERMAPS_PADDING + SIZEOF_HEADER))
150#define MAPS_TO_FPMAPS_PADDING (PADDING_TO_CONTINUATION_SIZE(SIZEOF_MAPS))
151
152#define BYTES_LEFT_IN_FIRST_PAGE (BYTES_PER_PAGE - \
153		(SIZEOF_HEADER + HEADER_TO_SUPERMAPS_PADDING + SIZEOF_SUPERMAPS + \
154		SUPERMAPS_TO_MAPS_PADDING + SIZEOF_MAPS + MAPS_TO_FPMAPS_PADDING))
155
156#if PACK_FIRST_PAGE_WITH_CONTINUATIONS
157
158#define FULL_BITMAPS_IN_FIRST_PAGE \
159		(BYTES_LEFT_IN_FIRST_PAGE / CONSUMED_BYTES_PER_BITMAP)
160#define REMAINDER_IN_FIRST_PAGE (BYTES_LEFT_IN_FIRST_PAGE - \
161		(FULL_BITMAPS_IN_FIRST_PAGE * CONSUMED_BYTES_PER_BITMAP) - \
162		(FULL_BITMAPS_IN_FIRST_PAGE ? 0 : ROUND_UP_TO_CONTINUATION_SIZE(BYTES_PER_BITMAP)))
163
164#define REMAINDERED_CONTINUATIONS_IN_FIRST_PAGE \
165		(REMAINDER_IN_FIRST_PAGE / DISPATCH_CONTINUATION_SIZE)
166#define CONTINUATIONS_IN_FIRST_PAGE (FULL_BITMAPS_IN_FIRST_PAGE * \
167		CONTINUATIONS_PER_BITMAP) + REMAINDERED_CONTINUATIONS_IN_FIRST_PAGE
168#define BITMAPS_IN_FIRST_PAGE (FULL_BITMAPS_IN_FIRST_PAGE + \
169		(REMAINDERED_CONTINUATIONS_IN_FIRST_PAGE == 0 ? 0 : 1))
170
171#define FPMAPS_TO_FPCONTS_PADDING (PADDING_TO_CONTINUATION_SIZE(\
172		BYTES_PER_BITMAP * BITMAPS_IN_FIRST_PAGE))
173
174#else // PACK_FIRST_PAGE_WITH_CONTINUATIONS
175
176#define MAPS_TO_CONTS_PADDING BYTES_LEFT_IN_FIRST_PAGE
177
178#endif // PACK_FIRST_PAGE_WITH_CONTINUATIONS
179
180#define AFTER_CONTS_PADDING (BYTES_PER_MAGAZINE - (BYTES_PER_PAGE + \
181		(DISPATCH_CONTINUATION_SIZE * CONTINUATIONS_PER_MAGAZINE)))
182
183// This is the object our allocator allocates: a chunk of memory rounded up
184// from sizeof(struct dispatch_continuation_s) to the cacheline size, so
185// unrelated continuations don't share cachelines. It'd be nice if
186// dispatch_continuation_s included this rounding/padding, but it doesn't.
187typedef char padded_continuation[DISPATCH_CONTINUATION_SIZE];
188
189// A dispatch_heap_t is the base address of an array of dispatch_magazine_s,
190// one magazine per CPU.
191typedef struct dispatch_magazine_s * dispatch_heap_t;
192
193struct dispatch_magazine_header_s {
194	// Link to the next heap in the chain. Only used in magazine 0's header
195	dispatch_heap_t dh_next;
196
197	// Points to the first bitmap in the page where this CPU succesfully
198	// allocated a continuation last time. Only used in the first heap.
199	bitmap_t *last_found_page;
200};
201
202// A magazine is a complex data structure. It must be exactly
203// PAGES_PER_MAGAZINE * PAGE_SIZE bytes long, and that value must be a
204// power of 2. (See magazine_for_continuation()).
205struct dispatch_magazine_s {
206	// See above.
207	struct dispatch_magazine_header_s header;
208
209	// Align supermaps as needed.
210#if HEADER_TO_SUPERMAPS_PADDING > 0
211	char _pad0[HEADER_TO_SUPERMAPS_PADDING];
212#endif
213
214	// Second-level bitmap; each set bit means a bitmap_t in maps[][]
215	// is completely full (and can be skipped while searching).
216	bitmap_t supermaps[SUPERMAPS_PER_MAGAZINE];
217
218	// Align maps to a cacheline.
219#if SUPERMAPS_TO_MAPS_PADDING > 0
220	char _pad1[SUPERMAPS_TO_MAPS_PADDING];
221#endif
222
223	// Each bit in maps[][] is the free/used state of a member of conts[][][].
224	bitmap_t maps[SUPERMAPS_PER_MAGAZINE][BITMAPS_PER_SUPERMAP];
225
226	// Align fp_maps to a cacheline.
227#if MAPS_TO_FPMAPS_PADDING > 0
228	char _pad2[MAPS_TO_FPMAPS_PADDING];
229#endif
230
231#if PACK_FIRST_PAGE_WITH_CONTINUATIONS
232	// Bitmaps for the continuations that live in the first page, which
233	// are treated specially (they have faster search code).
234	bitmap_t fp_maps[BITMAPS_IN_FIRST_PAGE];
235
236	// Align fp_conts to cacheline.
237#if FPMAPS_TO_FPCONTS_PADDING > 0
238	char _pad3[FPMAPS_TO_FPCONTS_PADDING];
239#endif
240
241	// Continuations that live in the first page.
242	padded_continuation fp_conts[CONTINUATIONS_IN_FIRST_PAGE];
243
244#else // PACK_FIRST_PAGE_WITH_CONTINUATIONS
245
246#if MAPS_TO_CONTS_PADDING > 0
247	char _pad4[MAPS_TO_CONTS_PADDING];
248#endif
249#endif // PACK_FIRST_PAGE_WITH_CONTINUATIONS
250
251	// This is the big array of continuations.
252	// This must start on a page boundary.
253	padded_continuation conts[SUPERMAPS_PER_MAGAZINE][BITMAPS_PER_SUPERMAP]
254			[CONTINUATIONS_PER_BITMAP];
255
256	// Fill the unused space to exactly BYTES_PER_MAGAZINE
257#if AFTER_CONTS_PADDING > 0
258	char _pad5[AFTER_CONTS_PADDING];
259#endif
260};
261
262#if DISPATCH_DEBUG
263#define DISPATCH_ALLOCATOR_SCRIBBLE ((uintptr_t)0xAFAFAFAFAFAFAFAF)
264#endif
265
266#endif // DISPATCH_ALLOCATOR
267
268#endif // __DISPATCH_ALLOCATOR_INTERNAL__
269