2 * sgen-internal.c: Internal lock-free memory allocator.
4 * Copyright (C) 2012 Xamarin Inc
6 * Licensed under the MIT license. See LICENSE file in the project root for full license information.
15 #include "mono/sgen/sgen-gc.h"
16 #include "mono/utils/lock-free-alloc.h"
17 #include "mono/sgen/sgen-memory-governor.h"
18 #include "mono/sgen/sgen-client.h"
21 * When allocating sgen memory we choose the allocator with the smallest slot size
22 * that can fit our requested size. These slots are allocated within a block that
23 * can contain at least 2 slots of the specific size.
25 * Currently, slots from 8 to 2044/2040 are allocated inside 4096 sized blocks,
26 * 2728 to 4092/4088 inside 8192 sized blocks, and higher inside 16384 sized
27 * blocks. We also need to make sure the slots are pointer size aligned so we
28 * don't allocate unaligned memory.
30 * The computation of these sizes spawns from two basic rules :
31 * - if we use slots of size s1 that fit n times in a block, it is illogical
32 * to use another slot of size s2 which also fits the same n times in a block.
33 * - if we use slots of size s1 that fit n times in a block, there is no
34 * s2 > s1 that can fit n times in the block. That would mean we are wasting memory
35 * when allocating size S where s1 < S <= s2.
37 #if SIZEOF_VOID_P == 4
38 static const int allocator_sizes [] = {
39 8, 16, 24, 32, 40, 48, 64, 80,
40 96, 124, 160, 192, 224, 252, 292, 340,
41 408, 452, 508, 584, 680, 816, 1020,
42 1364, 2044, 2728, 4092, 5460, 8188 };
44 static const int allocator_sizes [] = {
45 8, 16, 24, 32, 40, 48, 64, 80,
46 96, 128, 160, 192, 224, 248, 288, 336,
47 368, 448, 504, 584, 680, 816, 1016,
48 1360, 2040, 2728, 4088, 5456, 8184 };
51 #define NUM_ALLOCATORS (sizeof (allocator_sizes) / sizeof (int))
53 static int allocator_block_sizes [NUM_ALLOCATORS];
55 static MonoLockFreeAllocSizeClass size_classes [NUM_ALLOCATORS];
56 static MonoLockFreeAllocator allocators [NUM_ALLOCATORS];
58 #ifdef HEAVY_STATISTICS
59 static int allocator_sizes_stats [NUM_ALLOCATORS];
63 block_size (size_t slot_size)
65 static int pagesize = -1;
68 size_t aligned_slot_size = SGEN_ALIGN_UP_TO (slot_size, SIZEOF_VOID_P);
71 pagesize = mono_pagesize ();
73 for (size = pagesize; size < LOCK_FREE_ALLOC_SB_MAX_SIZE; size <<= 1) {
74 if (aligned_slot_size * 2 <= LOCK_FREE_ALLOC_SB_USABLE_SIZE (size))
77 return LOCK_FREE_ALLOC_SB_MAX_SIZE;
81 * Find the allocator index for memory chunks that can contain @size
85 index_for_size (size_t size)
88 /* do a binary search or lookup table later. */
89 for (slot = 0; slot < NUM_ALLOCATORS; ++slot) {
90 if (allocator_sizes [slot] >= size)
93 g_assert_not_reached ();
98 * Allocator indexes for the fixed INTERNAL_MEM_XXX types. -1 if that
101 static int fixed_type_allocator_indexes [INTERNAL_MEM_MAX];
104 sgen_register_fixed_internal_mem_type (int type, size_t size)
108 g_assert (type >= 0 && type < INTERNAL_MEM_MAX);
109 g_assert (size <= allocator_sizes [NUM_ALLOCATORS - 1]);
111 slot = index_for_size (size);
112 g_assert (slot >= 0);
114 if (fixed_type_allocator_indexes [type] == -1)
115 fixed_type_allocator_indexes [type] = slot;
117 if (fixed_type_allocator_indexes [type] != slot)
118 g_error ("Invalid double registration of type %d old slot %d new slot %d", type, fixed_type_allocator_indexes [type], slot);
123 description_for_type (int type)
126 case INTERNAL_MEM_PIN_QUEUE: return "pin-queue";
127 case INTERNAL_MEM_FRAGMENT: return "fragment";
128 case INTERNAL_MEM_SECTION: return "section";
129 case INTERNAL_MEM_SCAN_STARTS: return "scan-starts";
130 case INTERNAL_MEM_FIN_TABLE: return "fin-table";
131 case INTERNAL_MEM_FINALIZE_ENTRY: return "finalize-entry";
132 case INTERNAL_MEM_FINALIZE_READY: return "finalize-ready";
133 case INTERNAL_MEM_DISLINK_TABLE: return "dislink-table";
134 case INTERNAL_MEM_DISLINK: return "dislink";
135 case INTERNAL_MEM_ROOTS_TABLE: return "roots-table";
136 case INTERNAL_MEM_ROOT_RECORD: return "root-record";
137 case INTERNAL_MEM_STATISTICS: return "statistics";
138 case INTERNAL_MEM_STAT_PINNED_CLASS: return "pinned-class";
139 case INTERNAL_MEM_STAT_REMSET_CLASS: return "remset-class";
140 case INTERNAL_MEM_GRAY_QUEUE: return "gray-queue";
141 case INTERNAL_MEM_MS_TABLES: return "marksweep-tables";
142 case INTERNAL_MEM_MS_BLOCK_INFO: return "marksweep-block-info";
143 case INTERNAL_MEM_MS_BLOCK_INFO_SORT: return "marksweep-block-info-sort";
144 case INTERNAL_MEM_WORKER_DATA: return "worker-data";
145 case INTERNAL_MEM_THREAD_POOL_JOB: return "thread-pool-job";
146 case INTERNAL_MEM_BRIDGE_DATA: return "bridge-data";
147 case INTERNAL_MEM_OLD_BRIDGE_HASH_TABLE: return "old-bridge-hash-table";
148 case INTERNAL_MEM_OLD_BRIDGE_HASH_TABLE_ENTRY: return "old-bridge-hash-table-entry";
149 case INTERNAL_MEM_BRIDGE_HASH_TABLE: return "bridge-hash-table";
150 case INTERNAL_MEM_BRIDGE_HASH_TABLE_ENTRY: return "bridge-hash-table-entry";
151 case INTERNAL_MEM_TARJAN_BRIDGE_HASH_TABLE: return "tarjan-bridge-hash-table";
152 case INTERNAL_MEM_TARJAN_BRIDGE_HASH_TABLE_ENTRY: return "tarjan-bridge-hash-table-entry";
153 case INTERNAL_MEM_TARJAN_OBJ_BUCKET: return "tarjan-bridge-object-buckets";
154 case INTERNAL_MEM_BRIDGE_ALIVE_HASH_TABLE: return "bridge-alive-hash-table";
155 case INTERNAL_MEM_BRIDGE_ALIVE_HASH_TABLE_ENTRY: return "bridge-alive-hash-table-entry";
156 case INTERNAL_MEM_BRIDGE_DEBUG: return "bridge-debug";
157 case INTERNAL_MEM_TOGGLEREF_DATA: return "toggleref-data";
158 case INTERNAL_MEM_CARDTABLE_MOD_UNION: return "cardtable-mod-union";
159 case INTERNAL_MEM_BINARY_PROTOCOL: return "binary-protocol";
160 case INTERNAL_MEM_TEMPORARY: return "temporary";
161 case INTERNAL_MEM_LOG_ENTRY: return "log-entry";
162 case INTERNAL_MEM_COMPLEX_DESCRIPTORS: return "complex-descriptors";
164 const char *description = sgen_client_description_for_internal_mem_type (type);
165 SGEN_ASSERT (0, description, "Unknown internal mem type");
172 sgen_alloc_internal_dynamic (size_t size, int type, gboolean assert_on_failure)
177 if (size > allocator_sizes [NUM_ALLOCATORS - 1]) {
178 p = sgen_alloc_os_memory (size, (SgenAllocFlags)(SGEN_ALLOC_INTERNAL | SGEN_ALLOC_ACTIVATE), NULL, MONO_MEM_ACCOUNT_SGEN_INTERNAL);
180 sgen_assert_memory_alloc (NULL, size, description_for_type (type));
182 index = index_for_size (size);
184 #ifdef HEAVY_STATISTICS
185 ++ allocator_sizes_stats [index];
188 p = mono_lock_free_alloc (&allocators [index]);
190 sgen_assert_memory_alloc (NULL, size, description_for_type (type));
194 SGEN_ASSERT (0, !(((mword)p) & (sizeof(gpointer) - 1)), "Why do we allocate unaligned addresses ?");
199 sgen_free_internal_dynamic (void *addr, size_t size, int type)
204 if (size > allocator_sizes [NUM_ALLOCATORS - 1])
205 sgen_free_os_memory (addr, size, SGEN_ALLOC_INTERNAL, MONO_MEM_ACCOUNT_SGEN_INTERNAL);
207 mono_lock_free_free (addr, block_size (size));
211 sgen_alloc_internal (int type)
216 index = fixed_type_allocator_indexes [type];
217 g_assert (index >= 0 && index < NUM_ALLOCATORS);
219 #ifdef HEAVY_STATISTICS
220 ++ allocator_sizes_stats [index];
223 size = allocator_sizes [index];
225 p = mono_lock_free_alloc (&allocators [index]);
228 SGEN_ASSERT (0, !(((mword)p) & (sizeof(gpointer) - 1)), "Why do we allocate unaligned addresses ?");
234 sgen_free_internal (void *addr, int type)
241 index = fixed_type_allocator_indexes [type];
242 g_assert (index >= 0 && index < NUM_ALLOCATORS);
244 mono_lock_free_free (addr, allocator_block_sizes [index]);
248 sgen_dump_internal_mem_usage (FILE *heap_dump_file)
253 fprintf (heap_dump_file, "<other-mem-usage type=\"large-internal\" size=\"%lld\"/>\n", large_internal_bytes_alloced);
254 fprintf (heap_dump_file, "<other-mem-usage type=\"pinned-chunks\" size=\"%lld\"/>\n", pinned_chunk_bytes_alloced);
255 for (i = 0; i < INTERNAL_MEM_MAX; ++i) {
256 fprintf (heap_dump_file, "<other-mem-usage type=\"%s\" size=\"%ld\"/>\n",
257 description_for_type (i), unmanaged_allocator.small_internal_mem_bytes [i]);
263 sgen_report_internal_mem_usage (void)
266 #ifdef HEAVY_STATISTICS
267 printf ("size -> # allocations\n");
268 for (i = 0; i < NUM_ALLOCATORS; ++i)
269 printf ("%d -> %d\n", allocator_sizes [i], allocator_sizes_stats [i]);
274 sgen_init_internal_allocator (void)
278 for (i = 0; i < INTERNAL_MEM_MAX; ++i)
279 fixed_type_allocator_indexes [i] = -1;
281 for (i = 0; i < NUM_ALLOCATORS; ++i) {
282 allocator_block_sizes [i] = block_size (allocator_sizes [i]);
283 mono_lock_free_allocator_init_size_class (&size_classes [i], allocator_sizes [i], allocator_block_sizes [i]);
284 mono_lock_free_allocator_init_allocator (&allocators [i], &size_classes [i], MONO_MEM_ACCOUNT_SGEN_INTERNAL);
287 for (size = mono_pagesize (); size <= LOCK_FREE_ALLOC_SB_MAX_SIZE; size <<= 1) {
288 int max_size = (LOCK_FREE_ALLOC_SB_USABLE_SIZE (size) / 2) & ~(SIZEOF_VOID_P - 1);
290 * we assert that allocator_sizes contains the biggest possible object size
291 * per block which has to be an aligned address.
292 * (4K => 2040, 8k => 4088, 16k => 8184 on 64bits),
293 * so that we do not get different block sizes for sizes that should go to the same one
295 g_assert (allocator_sizes [index_for_size (max_size)] == max_size);
296 g_assert (block_size (max_size) == size);
297 if (size < LOCK_FREE_ALLOC_SB_MAX_SIZE)
298 g_assert (block_size (max_size + 1) == size << 1);