xref: /xnu-8792.41.9/osfmk/vm/vm_reclaim_internal.h (revision 5c2921b07a2480ab43ec66f5b9e41cb872bc554f)
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28 
29 #ifndef __VM_RECLAIM_INTERNAL__
30 #define __VM_RECLAIM_INTERNAL__
31 
32 #if CONFIG_DEFERRED_RECLAIM
33 
34 #ifdef XNU_KERNEL_PRIVATE
35 
36 #include <mach/mach_types.h>
37 #include <mach/mach_vm.h>
38 
39 typedef struct vm_deferred_reclamation_metadata_s *vm_deferred_reclamation_metadata_t;
40 
41 kern_return_t vm_deferred_reclamation_buffer_init_internal(task_t task, user_addr_t address, mach_vm_size_t size, user_addr_t indices);
42 
43 /*
44  * Deallocate the kernel metadata associated with this reclamation buffer
45  * Note that this does NOT free the memory in the buffer.
46  * This is called from the task_destroy path, so we're about to reclaim all of the task's memory
47  * anyways.
48  */
49 void vm_deferred_reclamation_buffer_deallocate(vm_deferred_reclamation_metadata_t metadata);
50 
51 kern_return_t vm_deferred_reclamation_buffer_synchronize_internal(task_t task, size_t max_entries_to_reclaim);
52 
53 __enum_decl(vm_deferred_reclamation_action_t, uint32_t, {
54 	RECLAIM_TRIM, // Reclaim a bit of memory from everyone
55 	RECLAIM_FULL, // Fully drain every reclaim buffer
56 	RECLAIM_ASYNC, // Drain the async reclaim queue
57 });
58 
59 /*
60  * Ask the deferred reclamation subsystem to reclaim memory.
61  * See the documentation for vm_deferred_reclamation_action above.
62  */
63 void vm_deferred_reclamation_reclaim_memory(vm_deferred_reclamation_action_t action);
64 /*
65  * Equivalent to vm_deferred_reclamation_reclaim_memory(RECLAIM_FULL);
66  */
67 void vm_deferred_reclamation_reclaim_all_memory(void);
68 
69 bool vm_deferred_reclamation_reclaim_from_task_async(task_t task);
70 bool vm_deferred_reclamation_reclaim_from_task_sync(task_t task, size_t max_entries_to_reclaim);
71 
72 kern_return_t vm_deferred_reclamation_buffer_update_reclaimable_bytes_internal(
73 	task_t task, size_t reclaimable_bytes);
74 
75 /*
76  * Create a fork of the given reclamation buffer for a new task.
77  * Parent buffer must be locked and will be unlocked on return.
78  *
79  * This must be called when forking a task that has a reclamation buffer
80  * to ensure that the kernel knows about the child's reclamation buffer.
81  * The caller must lock the parent's reclamation buffer BEFORE forking
82  * the parent's vm_map. Otherwise the parent's buffer could get reclaimed
83  * in between the map fork and the buffer fork causing the child's
84  * data strucutres to be out of sync.
85  */
86 vm_deferred_reclamation_metadata_t vm_deferred_reclamation_buffer_fork(
87 	task_t task,
88 	vm_deferred_reclamation_metadata_t parent);
89 
90 void vm_deferred_reclamation_buffer_lock(vm_deferred_reclamation_metadata_t metadata);
91 void vm_deferred_reclamation_buffer_unlock(vm_deferred_reclamation_metadata_t metadata);
92 
93 #if DEVELOPMENT || DEBUG
94 /*
95  * Testing helpers
96  */
97 bool vm_deferred_reclamation_block_until_pid_has_been_reclaimed(int pid);
98 #endif /* DEVELOPMENT || DEBUG */
99 
100 #endif /* XNU_KERNEL_PRIVATE */
101 #endif /* CONFIG_DEFERRED_RECLAIM */
102 #endif /*__VM_RECLAIM_INTERNAL__ */
103