1 /* 2 * Copyright (c) 2019 Apple Inc. All rights reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23 24 /* 25 * Purgeable spelling rules 26 * It is believed that the correct spelling is 27 * { 'p', 'u', 'r', 'g', 'e', 'a', 'b', 'l', 'e' }. 28 * However, there is one published API that likes to spell it without the 29 * first 'e', vm_purgable_control(). Since we can't change that API, 30 * here are the rules. 31 * All qualifiers defined in vm_purgable.h are spelled without the e. 32 * All other qualifiers are spelled with the e. 33 * Right now, there are remains of the wrong spelling throughout the code, 34 * vm_object_t.purgable for example. We expect to change these on occasion. 35 */ 36 37 #ifndef __VM_PURGEABLE_INTERNAL__ 38 #define __VM_PURGEABLE_INTERNAL__ 39 40 #include <kern/queue.h> 41 #include <vm/vm_purgeable_xnu.h> 42 43 enum purgeable_q_type { 44 PURGEABLE_Q_TYPE_OBSOLETE, 45 PURGEABLE_Q_TYPE_FIFO, 46 PURGEABLE_Q_TYPE_LIFO, 47 PURGEABLE_Q_TYPE_MAX 48 }; 49 50 typedef uint32_t token_idx_t; 51 typedef uint32_t token_cnt_t; 52 #define TOKEN_COUNT_MAX UINT32_MAX 53 54 #define NUM_VOLATILE_GROUPS 8 55 struct purgeable_q { 56 token_idx_t token_q_head; /* first token */ 57 token_idx_t token_q_tail; /* last token */ 58 token_idx_t token_q_unripe; /* first token which is not ripe */ 59 int32_t new_pages; 60 queue_head_t objq[NUM_VOLATILE_GROUPS]; 61 enum purgeable_q_type type; 62 #if MACH_ASSERT 63 int debug_count_tokens; 64 int debug_count_objects; 65 #endif 66 }; 67 68 typedef struct purgeable_q * purgeable_q_t; 69 70 extern struct purgeable_q purgeable_queues[PURGEABLE_Q_TYPE_MAX]; 71 extern queue_head_t purgeable_nonvolatile_queue; 72 extern int purgeable_nonvolatile_count; 73 extern int32_t token_new_pagecount; 74 #define TOKEN_NEW_PAGECOUNT_MAX INT32_MAX 75 extern int available_for_purge; 76 77 78 /* 79 * Locking: 80 * the token counters are protected by the vm_page_queue_lock, since they're 81 * mostly used in that context and we don't want to do a lot of extra locking 82 * the purgeable page queues are protected by a separate lock since they're 83 * mostly used on a user context and we don't want any contention with the 84 * pageout daemon. 85 */ 86 decl_lck_mtx_data(extern, vm_purgeable_queue_lock); 87 88 /* add a new token to queue. called by vm_object_purgeable_control */ 89 /* enter with page queue locked */ 90 kern_return_t vm_purgeable_token_add(purgeable_q_t queue); 91 92 /* enter with page queue locked */ 93 void vm_purgeable_token_delete_first(purgeable_q_t queue); 94 void vm_purgeable_token_delete_last(purgeable_q_t queue); 95 96 /* 97 * decrement token counters. 98 * enter with page queue locked 99 */ 100 void vm_purgeable_q_advance_all(void); 101 102 /* purge all volatile objects now */ 103 void vm_purgeable_object_purge_all(void); 104 105 /* insert purgeable object into queue */ 106 void vm_purgeable_object_add(vm_object_t object, purgeable_q_t queue, int group); 107 108 /* look for object. If found, remove from purgeable queue. */ 109 purgeable_q_t vm_purgeable_object_remove(vm_object_t object); 110 111 void vm_purgeable_nonvolatile_enqueue(vm_object_t object, task_t task); 112 void vm_purgeable_nonvolatile_dequeue(vm_object_t object); 113 void vm_purgeable_accounting(vm_object_t object, 114 vm_purgable_t old_state); 115 void vm_object_owner_compressed_update(vm_object_t object, 116 int delta); 117 118 #define PURGEABLE_LOOP_MAX 64 119 120 #endif /* __VM_PURGEABLE_INTERNAL__ */ 121