xref: /xnu-11417.101.15/osfmk/vm/vm_reclaim_xnu.h (revision e3723e1f17661b24996789d8afc084c0c3303b26)
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28 
29 #ifndef __VM_RECLAIM_XNU__
30 #define __VM_RECLAIM_XNU__
31 
32 #if XNU_KERNEL_PRIVATE
33 #if CONFIG_DEFERRED_RECLAIM
34 #include <mach/mach_types.h>
35 #if BSD_KERNEL_PRIVATE
36 #include <mach/mach_vm.h>
37 #else /* BSD_KERNEL_PRIVATE */
38 #include <mach/mach_vm_server.h>
39 #endif /* BSD_KERNEL_PRIVATE */
40 
41 typedef struct vm_deferred_reclamation_metadata_s *vm_deferred_reclamation_metadata_t;
42 
43 __enum_closed_decl(vm_deferred_reclamation_gc_action_t, uint8_t, {
44 	/* Trim all buffers */
45 	RECLAIM_GC_TRIM = 0,
46 	/* Fully drain all buffers */
47 	RECLAIM_GC_DRAIN = 1,
48 	/* Drain any buffers belonging to suspended tasks */
49 	RECLAIM_GC_SCAVENGE = 2,
50 });
51 
52 __options_closed_decl(vm_deferred_reclamation_options_t, uint8_t, {
53 	RECLAIM_OPTIONS_NONE = 0x00,
54 	/* Do not fault on the reclaim buffer if it is not resident */
55 	RECLAIM_NO_FAULT     = 0x01,
56 	/* Do not wait to acquire the buffer if it is owned by another thread */
57 	RECLAIM_NO_WAIT      = 0x02,
58 });
59 
60 /*
61  * Deallocate the kernel metadata associated with this reclamation buffer
62  * Note that this does NOT free the memory in the buffer.
63  * This is called from the task_destroy path, so we're about to reclaim all of the task's memory
64  * anyways.
65  */
66 void vm_deferred_reclamation_buffer_deallocate(vm_deferred_reclamation_metadata_t metadata);
67 
68 /*
69  * Synchronously drain all reclamation ring's belonging to a task.
70  */
71 kern_return_t vm_deferred_reclamation_task_drain(
72 	task_t                            task,
73 	vm_deferred_reclamation_options_t options);
74 
75 /*
76  * Return true if this task has a reclamation ring
77  */
78 bool vm_deferred_reclamation_task_has_ring(task_t task);
79 
80 /*
81  * Create a fork of the given reclamation buffer for a new task.
82  * Parent buffer must be locked and will be unlocked on return.
83  *
84  * This must be called when forking a task that has a reclamation buffer
85  * to duplicate the parent's buffer, and the new buffer must later be
86  * registered by vm_deferred_reclamation_task_fork_register.
87  *
88  * The caller must lock the parent's reclamation buffer BEFORE forking
89  * the parent's vm_map. Otherwise the parent's buffer could get reclaimed
90  * in between the map fork and the buffer fork causing the child's
91  * data strucutres to be out of sync.
92  */
93 vm_deferred_reclamation_metadata_t vm_deferred_reclamation_task_fork(
94 	task_t task,
95 	vm_deferred_reclamation_metadata_t parent);
96 
97 /*
98  * Add a reclamation buffer returned by vm_deferred_reclamation_task_fork to
99  * the global reclamation queues.
100  *
101  * The child task should call this to ensure that the kernel knows about its
102  * reclamation buffer. This must happen after the child's address space is
103  * fully initialized and able to recieve VM API calls.
104  */
105 void
106 vm_deferred_reclamation_task_fork_register(vm_deferred_reclamation_metadata_t metadata);
107 
108 /*
109  * Set the current thread as the owner of a reclaim buffer. May block. Will
110  * propagate priority. Should be called before forking the owning task.
111  */
112 void vm_deferred_reclamation_ring_own(vm_deferred_reclamation_metadata_t metadata);
113 
114 /*
115  * Release ownership of a reclaim buffer and wakeup any threads waiting for
116  * ownership. Must be called from the thread that acquired ownership.
117  */
118 void vm_deferred_reclamation_ring_disown(vm_deferred_reclamation_metadata_t metadata);
119 
120 /*
121  * Should be called when a task is suspended -- will trigger asynchronous
122  * reclamation of any reclaim rings owned by the task.
123  */
124 void vm_deferred_reclamation_task_suspend(task_t task);
125 
126 /*
127  * Perform Garbage Collection on all reclaim rings
128  */
129 void vm_deferred_reclamation_gc(vm_deferred_reclamation_gc_action_t action,
130     vm_deferred_reclamation_options_t options);
131 
132 #endif /* CONFIG_DEFERRED_RECLAIM */
133 #endif /* XNU_KERNEL_PRIVATE */
134 #endif  /* __VM_RECLAIM_XNU__ */
135