xref: /xnu-8020.101.4/osfmk/kern/priority_queue.h (revision e7776783b89a353188416a9a346c6cdb4928faad)
1*e7776783SApple OSS Distributions /*
2*e7776783SApple OSS Distributions  * Copyright (c) 2018 Apple Inc. All rights reserved.
3*e7776783SApple OSS Distributions  *
4*e7776783SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*e7776783SApple OSS Distributions  *
6*e7776783SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*e7776783SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*e7776783SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
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14*e7776783SApple OSS Distributions  *
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28*e7776783SApple OSS Distributions 
29*e7776783SApple OSS Distributions #ifndef _KERN_PRIORITY_QUEUE_H_
30*e7776783SApple OSS Distributions #define _KERN_PRIORITY_QUEUE_H_
31*e7776783SApple OSS Distributions 
32*e7776783SApple OSS Distributions #if KERNEL
33*e7776783SApple OSS Distributions #include <kern/kern_types.h>
34*e7776783SApple OSS Distributions #include <kern/macro_help.h>
35*e7776783SApple OSS Distributions #include <kern/assert.h>
36*e7776783SApple OSS Distributions #endif
37*e7776783SApple OSS Distributions 
38*e7776783SApple OSS Distributions #include <stdbool.h>
39*e7776783SApple OSS Distributions #include <sys/cdefs.h>
40*e7776783SApple OSS Distributions 
41*e7776783SApple OSS Distributions #pragma GCC visibility push(hidden)
42*e7776783SApple OSS Distributions 
43*e7776783SApple OSS Distributions __BEGIN_DECLS
44*e7776783SApple OSS Distributions 
45*e7776783SApple OSS Distributions /*
46*e7776783SApple OSS Distributions  * A generic priorty ordered queue implementation based on pairing heaps.
47*e7776783SApple OSS Distributions  *
48*e7776783SApple OSS Distributions  * Reference Papers:
49*e7776783SApple OSS Distributions  * - A Back-to-Basics Empirical Study of Priority Queues (https://arxiv.org/abs/1403.0252)
50*e7776783SApple OSS Distributions  * - The Pairing Heap: A New Form of Self-Adjusting Heap
51*e7776783SApple OSS Distributions  *   (https://www.cs.cmu.edu/~sleator/papers/pairing-heaps.pdf)
52*e7776783SApple OSS Distributions  *
53*e7776783SApple OSS Distributions  * The XNU implementation is a basic version of the pairing heap.
54*e7776783SApple OSS Distributions  * It allows for O(1) insertion and amortized O(log n) deletion.
55*e7776783SApple OSS Distributions  *
56*e7776783SApple OSS Distributions  * It is not a stable data structure by default since adding stability would
57*e7776783SApple OSS Distributions  * need more pointers and hence more memory.
58*e7776783SApple OSS Distributions  *
59*e7776783SApple OSS Distributions  * Type of queues
60*e7776783SApple OSS Distributions  *
61*e7776783SApple OSS Distributions  *         There are several types of priority queues, with types named:
62*e7776783SApple OSS Distributions  *
63*e7776783SApple OSS Distributions  *         struct priority_queue_<subtype>_<min|max>
64*e7776783SApple OSS Distributions  *
65*e7776783SApple OSS Distributions  *         In the rest of this header, `struct priority_queue` is used as
66*e7776783SApple OSS Distributions  *         a generic type to mean any priority_queue type.
67*e7776783SApple OSS Distributions  *
68*e7776783SApple OSS Distributions  *         min/max refers to whether the priority queue is a min or a max heap.
69*e7776783SApple OSS Distributions  *
70*e7776783SApple OSS Distributions  *         the subtype can be:
71*e7776783SApple OSS Distributions  *
72*e7776783SApple OSS Distributions  *         - sched, in which case the key is built in the linkage and assumed to
73*e7776783SApple OSS Distributions  *           be a scheduler priority.
74*e7776783SApple OSS Distributions  *
75*e7776783SApple OSS Distributions  *         - sched_stable, in which case the key is a combination of:
76*e7776783SApple OSS Distributions  *             * a scheduler priority
77*e7776783SApple OSS Distributions  *             * whether the entry was preempted or not
78*e7776783SApple OSS Distributions  *             * a timestamp.
79*e7776783SApple OSS Distributions  *
80*e7776783SApple OSS Distributions  *         - generic, in which case a comparison function must be passed to
81*e7776783SApple OSS Distributions  *           the priority_queue_init.
82*e7776783SApple OSS Distributions  *
83*e7776783SApple OSS Distributions  * Element Linkage:
84*e7776783SApple OSS Distributions  *
85*e7776783SApple OSS Distributions  *         Both types use a common queue head and linkage pattern.
86*e7776783SApple OSS Distributions  *         The head of a priority queue is declared as:
87*e7776783SApple OSS Distributions  *
88*e7776783SApple OSS Distributions  *              struct priority_queue_<subtype>_<min|max> pq_head;
89*e7776783SApple OSS Distributions  *
90*e7776783SApple OSS Distributions  *         Elements in this queue are linked together using one of the struct
91*e7776783SApple OSS Distributions  *         priority_queue_entry_<subtype> objects embedded within a structure:
92*e7776783SApple OSS Distributions  *
93*e7776783SApple OSS Distributions  *              struct some_data {
94*e7776783SApple OSS Distributions  *                      int field1;
95*e7776783SApple OSS Distributions  *                      int field2;
96*e7776783SApple OSS Distributions  *                      ...
97*e7776783SApple OSS Distributions  *                      struct priority_queue_entry link;
98*e7776783SApple OSS Distributions  *                      ...
99*e7776783SApple OSS Distributions  *                      int last_field;
100*e7776783SApple OSS Distributions  *              };
101*e7776783SApple OSS Distributions  *         struct some_data is referred to as the queue "element"
102*e7776783SApple OSS Distributions  *
103*e7776783SApple OSS Distributions  *         This method uses the next, prev and child pointers of the struct
104*e7776783SApple OSS Distributions  *         priority_queue_entry linkage object embedded in a queue element to
105*e7776783SApple OSS Distributions  *         point to other elements in the queue. The head of the priority queue
106*e7776783SApple OSS Distributions  *         (the priority_queue object) will point to the root of the pairing
107*e7776783SApple OSS Distributions  *         heap (NULL if heap is empty). This method allows multiple chains
108*e7776783SApple OSS Distributions  *         through a given object, by embedding multiple priority_queue_entry
109*e7776783SApple OSS Distributions  *         objects in the structure, while simultaneously providing fast removal
110*e7776783SApple OSS Distributions  *         and insertion into the heap using only priority_queue_entry object
111*e7776783SApple OSS Distributions  *         pointers.
112*e7776783SApple OSS Distributions  */
113*e7776783SApple OSS Distributions 
114*e7776783SApple OSS Distributions 
115*e7776783SApple OSS Distributions /*
116*e7776783SApple OSS Distributions  * Priority keys maintained by the data structure.
117*e7776783SApple OSS Distributions  * Since the priority is packed in the node itself, it restricts keys to be 16-bits only.
118*e7776783SApple OSS Distributions  */
119*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_KEY_NONE             0
120*e7776783SApple OSS Distributions typedef uint16_t priority_queue_key_t;
121*e7776783SApple OSS Distributions 
122*e7776783SApple OSS Distributions #ifdef __LP64__
123*e7776783SApple OSS Distributions 
124*e7776783SApple OSS Distributions /*
125*e7776783SApple OSS Distributions  * For 64-bit platforms, pack the priority key into the child pointer
126*e7776783SApple OSS Distributions  * The packing/unpacking is done using a compiler trick to sign extend long.
127*e7776783SApple OSS Distributions  * This avoids additional NULL checks which are needed in typical packing
128*e7776783SApple OSS Distributions  * implementation. The idea is to define the packed location as a long and
129*e7776783SApple OSS Distributions  * for unpacking simply cast it to a full pointer which sign extends it.
130*e7776783SApple OSS Distributions  */
131*e7776783SApple OSS Distributions #if CONFIG_KERNEL_TBI && KASAN_TBI
132*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_ENTRY_CHILD_BITS     44
133*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_ENTRY_TAG_BITS       4
134*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_ENTRY_KEY_BITS       16
135*e7776783SApple OSS Distributions #else /* CONFIG_KERNEL_TBI && KASAN_TBI */
136*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_ENTRY_CHILD_BITS     48
137*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_ENTRY_KEY_BITS       16
138*e7776783SApple OSS Distributions #endif /* CONFIG_KERNEL_TBI && KASAN_TBI */
139*e7776783SApple OSS Distributions 
140*e7776783SApple OSS Distributions typedef struct priority_queue_entry {
141*e7776783SApple OSS Distributions 	struct priority_queue_entry        *next;
142*e7776783SApple OSS Distributions 	struct priority_queue_entry        *prev;
143*e7776783SApple OSS Distributions 	long                                __key: PRIORITY_QUEUE_ENTRY_KEY_BITS;
144*e7776783SApple OSS Distributions #if CONFIG_KERNEL_TBI && KASAN_TBI
145*e7776783SApple OSS Distributions 	unsigned long                       tag: PRIORITY_QUEUE_ENTRY_TAG_BITS;
146*e7776783SApple OSS Distributions #endif /* CONFIG_KERNEL_TBI && KASAN_TBI */
147*e7776783SApple OSS Distributions 	long                                child: PRIORITY_QUEUE_ENTRY_CHILD_BITS;
148*e7776783SApple OSS Distributions } *priority_queue_entry_t;
149*e7776783SApple OSS Distributions 
150*e7776783SApple OSS Distributions typedef struct priority_queue_entry_deadline {
151*e7776783SApple OSS Distributions 	struct priority_queue_entry_deadline *next;
152*e7776783SApple OSS Distributions 	struct priority_queue_entry_deadline *prev;
153*e7776783SApple OSS Distributions 	long                                  __key: PRIORITY_QUEUE_ENTRY_KEY_BITS;
154*e7776783SApple OSS Distributions #if CONFIG_KERNEL_TBI && KASAN_TBI
155*e7776783SApple OSS Distributions 	unsigned long                         tag: PRIORITY_QUEUE_ENTRY_TAG_BITS;
156*e7776783SApple OSS Distributions #endif /* CONFIG_KERNEL_TBI && KASAN_TBI */
157*e7776783SApple OSS Distributions 	long                                  child: PRIORITY_QUEUE_ENTRY_CHILD_BITS;
158*e7776783SApple OSS Distributions 	uint64_t                              deadline;
159*e7776783SApple OSS Distributions } *priority_queue_entry_deadline_t;
160*e7776783SApple OSS Distributions 
161*e7776783SApple OSS Distributions typedef struct priority_queue_entry_sched {
162*e7776783SApple OSS Distributions 	struct priority_queue_entry_sched  *next;
163*e7776783SApple OSS Distributions 	struct priority_queue_entry_sched  *prev;
164*e7776783SApple OSS Distributions 	long                                key: PRIORITY_QUEUE_ENTRY_KEY_BITS;
165*e7776783SApple OSS Distributions #if CONFIG_KERNEL_TBI && KASAN_TBI
166*e7776783SApple OSS Distributions 	unsigned long                       tag: PRIORITY_QUEUE_ENTRY_TAG_BITS;
167*e7776783SApple OSS Distributions #endif /* CONFIG_KERNEL_TBI && KASAN_TBI */
168*e7776783SApple OSS Distributions 	long                                child: PRIORITY_QUEUE_ENTRY_CHILD_BITS;
169*e7776783SApple OSS Distributions } *priority_queue_entry_sched_t;
170*e7776783SApple OSS Distributions 
171*e7776783SApple OSS Distributions typedef struct priority_queue_entry_stable {
172*e7776783SApple OSS Distributions 	struct priority_queue_entry_stable *next;
173*e7776783SApple OSS Distributions 	struct priority_queue_entry_stable *prev;
174*e7776783SApple OSS Distributions 	long                                key: PRIORITY_QUEUE_ENTRY_KEY_BITS;
175*e7776783SApple OSS Distributions #if CONFIG_KERNEL_TBI && KASAN_TBI
176*e7776783SApple OSS Distributions 	unsigned long                       tag: PRIORITY_QUEUE_ENTRY_TAG_BITS;
177*e7776783SApple OSS Distributions #endif /* CONFIG_KERNEL_TBI && KASAN_TBI */
178*e7776783SApple OSS Distributions 	long                                child: PRIORITY_QUEUE_ENTRY_CHILD_BITS;
179*e7776783SApple OSS Distributions 	uint64_t                            stamp;
180*e7776783SApple OSS Distributions } *priority_queue_entry_stable_t;
181*e7776783SApple OSS Distributions 
182*e7776783SApple OSS Distributions #else /* __LP64__ */
183*e7776783SApple OSS Distributions 
184*e7776783SApple OSS Distributions typedef struct priority_queue_entry {
185*e7776783SApple OSS Distributions 	struct priority_queue_entry        *next;
186*e7776783SApple OSS Distributions 	struct priority_queue_entry        *prev;
187*e7776783SApple OSS Distributions 	long                                child;
188*e7776783SApple OSS Distributions } *priority_queue_entry_t;
189*e7776783SApple OSS Distributions 
190*e7776783SApple OSS Distributions typedef struct priority_queue_entry_deadline {
191*e7776783SApple OSS Distributions 	struct priority_queue_entry_deadline *next;
192*e7776783SApple OSS Distributions 	struct priority_queue_entry_deadline *prev;
193*e7776783SApple OSS Distributions 	long                                  child;
194*e7776783SApple OSS Distributions 	uint64_t                              deadline;
195*e7776783SApple OSS Distributions } *priority_queue_entry_deadline_t;
196*e7776783SApple OSS Distributions 
197*e7776783SApple OSS Distributions /*
198*e7776783SApple OSS Distributions  * For 32-bit platforms, use an extra field to store the key since child pointer packing
199*e7776783SApple OSS Distributions  * is not an option. The child is maintained as a long to use the same packing/unpacking
200*e7776783SApple OSS Distributions  * routines that work for 64-bit platforms.
201*e7776783SApple OSS Distributions  */
202*e7776783SApple OSS Distributions typedef struct priority_queue_entry_sched {
203*e7776783SApple OSS Distributions 	struct priority_queue_entry_sched  *next;
204*e7776783SApple OSS Distributions 	struct priority_queue_entry_sched  *prev;
205*e7776783SApple OSS Distributions 	long                                child;
206*e7776783SApple OSS Distributions 	priority_queue_key_t                key;
207*e7776783SApple OSS Distributions } *priority_queue_entry_sched_t;
208*e7776783SApple OSS Distributions 
209*e7776783SApple OSS Distributions typedef struct priority_queue_entry_stable {
210*e7776783SApple OSS Distributions 	struct priority_queue_entry_stable *next;
211*e7776783SApple OSS Distributions 	struct priority_queue_entry_stable *prev;
212*e7776783SApple OSS Distributions 	long                                child;
213*e7776783SApple OSS Distributions 	priority_queue_key_t                key;
214*e7776783SApple OSS Distributions 	uint64_t                            stamp;
215*e7776783SApple OSS Distributions } *priority_queue_entry_stable_t;
216*e7776783SApple OSS Distributions 
217*e7776783SApple OSS Distributions #endif /* __LP64__ */
218*e7776783SApple OSS Distributions 
219*e7776783SApple OSS Distributions /*
220*e7776783SApple OSS Distributions  * Comparator block prototype
221*e7776783SApple OSS Distributions  * Args:
222*e7776783SApple OSS Distributions  *      - elements to compare
223*e7776783SApple OSS Distributions  * Return:
224*e7776783SApple OSS Distributions  * comparision result to indicate relative ordering of elements according to the heap type
225*e7776783SApple OSS Distributions  */
226*e7776783SApple OSS Distributions typedef int (^priority_queue_compare_fn_t)(struct priority_queue_entry *e1,
227*e7776783SApple OSS Distributions     struct priority_queue_entry *e2);
228*e7776783SApple OSS Distributions 
229*e7776783SApple OSS Distributions #define priority_heap_compare_ints(a, b) ((a) < (b) ? 1 : -1)
230*e7776783SApple OSS Distributions 
231*e7776783SApple OSS Distributions #define priority_heap_make_comparator(name1, name2, type, field, ...) \
232*e7776783SApple OSS Distributions 	(^int(priority_queue_entry_t __e1, priority_queue_entry_t __e2){        \
233*e7776783SApple OSS Distributions 	    type *name1 = pqe_element_fast(__e1, type, field);                  \
234*e7776783SApple OSS Distributions 	    type *name2 = pqe_element_fast(__e2, type, field);                  \
235*e7776783SApple OSS Distributions 	    __VA_ARGS__;                                                        \
236*e7776783SApple OSS Distributions 	})
237*e7776783SApple OSS Distributions 
238*e7776783SApple OSS Distributions /*
239*e7776783SApple OSS Distributions  * Type for any priority queue, only used for documentation purposes.
240*e7776783SApple OSS Distributions  */
241*e7776783SApple OSS Distributions struct priority_queue;
242*e7776783SApple OSS Distributions 
243*e7776783SApple OSS Distributions /*
244*e7776783SApple OSS Distributions  * Type of generic heaps
245*e7776783SApple OSS Distributions  */
246*e7776783SApple OSS Distributions struct priority_queue_min {
247*e7776783SApple OSS Distributions 	struct priority_queue_entry *pq_root;
248*e7776783SApple OSS Distributions 	priority_queue_compare_fn_t  pq_cmp_fn;
249*e7776783SApple OSS Distributions };
250*e7776783SApple OSS Distributions struct priority_queue_max {
251*e7776783SApple OSS Distributions 	struct priority_queue_entry *pq_root;
252*e7776783SApple OSS Distributions 	priority_queue_compare_fn_t  pq_cmp_fn;
253*e7776783SApple OSS Distributions };
254*e7776783SApple OSS Distributions 
255*e7776783SApple OSS Distributions /*
256*e7776783SApple OSS Distributions  * Type of deadline heaps
257*e7776783SApple OSS Distributions  */
258*e7776783SApple OSS Distributions struct priority_queue_deadline_min {
259*e7776783SApple OSS Distributions 	struct priority_queue_entry_deadline *pq_root;
260*e7776783SApple OSS Distributions };
261*e7776783SApple OSS Distributions struct priority_queue_deadline_max {
262*e7776783SApple OSS Distributions 	struct priority_queue_entry_deadline *pq_root;
263*e7776783SApple OSS Distributions };
264*e7776783SApple OSS Distributions 
265*e7776783SApple OSS Distributions /*
266*e7776783SApple OSS Distributions  * Type of scheduler priority based heaps
267*e7776783SApple OSS Distributions  */
268*e7776783SApple OSS Distributions struct priority_queue_sched_min {
269*e7776783SApple OSS Distributions 	struct priority_queue_entry_sched *pq_root;
270*e7776783SApple OSS Distributions };
271*e7776783SApple OSS Distributions struct priority_queue_sched_max {
272*e7776783SApple OSS Distributions 	struct priority_queue_entry_sched *pq_root;
273*e7776783SApple OSS Distributions };
274*e7776783SApple OSS Distributions 
275*e7776783SApple OSS Distributions /*
276*e7776783SApple OSS Distributions  * Type of scheduler priority based stable heaps
277*e7776783SApple OSS Distributions  */
278*e7776783SApple OSS Distributions struct priority_queue_sched_stable_min {
279*e7776783SApple OSS Distributions 	struct priority_queue_entry_stable *pq_root;
280*e7776783SApple OSS Distributions };
281*e7776783SApple OSS Distributions struct priority_queue_sched_stable_max {
282*e7776783SApple OSS Distributions 	struct priority_queue_entry_stable *pq_root;
283*e7776783SApple OSS Distributions };
284*e7776783SApple OSS Distributions 
285*e7776783SApple OSS Distributions #pragma mark generic interface
286*e7776783SApple OSS Distributions 
287*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_INITIALIZER { .pq_root = NULL }
288*e7776783SApple OSS Distributions 
289*e7776783SApple OSS Distributions #define __pqueue_overloadable  __attribute__((overloadable))
290*e7776783SApple OSS Distributions 
291*e7776783SApple OSS Distributions #define priority_queue_is_min_heap(pq) _Generic(pq, \
292*e7776783SApple OSS Distributions 	struct priority_queue_min *: true, \
293*e7776783SApple OSS Distributions 	struct priority_queue_max *: false, \
294*e7776783SApple OSS Distributions 	struct priority_queue_deadline_min *: true, \
295*e7776783SApple OSS Distributions 	struct priority_queue_deadline_max *: false, \
296*e7776783SApple OSS Distributions 	struct priority_queue_sched_min *: true, \
297*e7776783SApple OSS Distributions 	struct priority_queue_sched_max *: false, \
298*e7776783SApple OSS Distributions 	struct priority_queue_sched_stable_min *: true, \
299*e7776783SApple OSS Distributions 	struct priority_queue_sched_stable_max *: false)
300*e7776783SApple OSS Distributions 
301*e7776783SApple OSS Distributions #define priority_queue_is_max_heap(pq) \
302*e7776783SApple OSS Distributions 	(!priority_queue_is_min_heap(pq))
303*e7776783SApple OSS Distributions 
304*e7776783SApple OSS Distributions /*
305*e7776783SApple OSS Distributions  *      Macro:          pqe_element_fast
306*e7776783SApple OSS Distributions  *      Function:
307*e7776783SApple OSS Distributions  *              Convert a priority_queue_entry_t to a queue element pointer.
308*e7776783SApple OSS Distributions  *              Get a pointer to the user-defined element containing
309*e7776783SApple OSS Distributions  *              a given priority_queue_entry_t
310*e7776783SApple OSS Distributions  *
311*e7776783SApple OSS Distributions  *              The fast variant assumes that `qe` is not NULL
312*e7776783SApple OSS Distributions  *      Header:
313*e7776783SApple OSS Distributions  *              pqe_element_fast(qe, type, field)
314*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> qe
315*e7776783SApple OSS Distributions  *                      <type> type of element in priority queue
316*e7776783SApple OSS Distributions  *                      <field> chain field in (*<type>)
317*e7776783SApple OSS Distributions  *      Returns:
318*e7776783SApple OSS Distributions  *              <type *> containing qe
319*e7776783SApple OSS Distributions  */
320*e7776783SApple OSS Distributions #define pqe_element_fast(qe, type, field)  __container_of(qe, type, field)
321*e7776783SApple OSS Distributions 
322*e7776783SApple OSS Distributions /*
323*e7776783SApple OSS Distributions  *      Macro:          pqe_element
324*e7776783SApple OSS Distributions  *      Function:
325*e7776783SApple OSS Distributions  *              Convert a priority_queue_entry_t to a queue element pointer.
326*e7776783SApple OSS Distributions  *              Get a pointer to the user-defined element containing
327*e7776783SApple OSS Distributions  *              a given priority_queue_entry_t
328*e7776783SApple OSS Distributions  *
329*e7776783SApple OSS Distributions  *              The non fast variant handles NULL `qe`
330*e7776783SApple OSS Distributions  *      Header:
331*e7776783SApple OSS Distributions  *              pqe_element(qe, type, field)
332*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> qe
333*e7776783SApple OSS Distributions  *                      <type> type of element in priority queue
334*e7776783SApple OSS Distributions  *                      <field> chain field in (*<type>)
335*e7776783SApple OSS Distributions  *      Returns:
336*e7776783SApple OSS Distributions  *              <type *> containing qe
337*e7776783SApple OSS Distributions  */
338*e7776783SApple OSS Distributions #define pqe_element(qe, type, field)  ({                                        \
339*e7776783SApple OSS Distributions 	__auto_type _tmp_entry = (qe);                                          \
340*e7776783SApple OSS Distributions 	_tmp_entry ? pqe_element_fast(_tmp_entry, type, field) : ((type *)NULL);\
341*e7776783SApple OSS Distributions })
342*e7776783SApple OSS Distributions 
343*e7776783SApple OSS Distributions /*
344*e7776783SApple OSS Distributions  * Priority Queue functionality routines
345*e7776783SApple OSS Distributions  */
346*e7776783SApple OSS Distributions 
347*e7776783SApple OSS Distributions /*
348*e7776783SApple OSS Distributions  *      Macro:          priority_queue_empty
349*e7776783SApple OSS Distributions  *      Function:
350*e7776783SApple OSS Distributions  *              Tests whether a priority queue is empty.
351*e7776783SApple OSS Distributions  *      Header:
352*e7776783SApple OSS Distributions  *              boolean_t priority_queue_empty(pq)
353*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
354*e7776783SApple OSS Distributions  */
355*e7776783SApple OSS Distributions #define priority_queue_empty(pq)         ((pq)->pq_root == NULL)
356*e7776783SApple OSS Distributions 
357*e7776783SApple OSS Distributions /*
358*e7776783SApple OSS Distributions  *      Macro:          priority_queue_init
359*e7776783SApple OSS Distributions  *      Function:
360*e7776783SApple OSS Distributions  *              Initialize a <struct priority_queue *>.
361*e7776783SApple OSS Distributions  *      Header:
362*e7776783SApple OSS Distributions  *              priority_queue_init(pq)
363*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
364*e7776783SApple OSS Distributions  *                      (optional) <cmp_fn> comparator function
365*e7776783SApple OSS Distributions  *      Returns:
366*e7776783SApple OSS Distributions  *              None
367*e7776783SApple OSS Distributions  */
368*e7776783SApple OSS Distributions __pqueue_overloadable
369*e7776783SApple OSS Distributions extern void
370*e7776783SApple OSS Distributions priority_queue_init(struct priority_queue *pq, ...);
371*e7776783SApple OSS Distributions 
372*e7776783SApple OSS Distributions /*
373*e7776783SApple OSS Distributions  *      Macro:          priority_queue_entry_init
374*e7776783SApple OSS Distributions  *      Function:
375*e7776783SApple OSS Distributions  *              Initialize a priority_queue_entry_t
376*e7776783SApple OSS Distributions  *      Header:
377*e7776783SApple OSS Distributions  *              priority_queue_entry_init(qe)
378*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> qe
379*e7776783SApple OSS Distributions  *      Returns:
380*e7776783SApple OSS Distributions  *              None
381*e7776783SApple OSS Distributions  */
382*e7776783SApple OSS Distributions #define priority_queue_entry_init(qe) \
383*e7776783SApple OSS Distributions 	__builtin_bzero(qe, sizeof(*(qe)))
384*e7776783SApple OSS Distributions 
385*e7776783SApple OSS Distributions /*
386*e7776783SApple OSS Distributions  *      Macro:          priority_queue_destroy
387*e7776783SApple OSS Distributions  *      Function:
388*e7776783SApple OSS Distributions  *              Destroy a priority queue safely. This routine accepts a callback
389*e7776783SApple OSS Distributions  *              to handle any cleanup for elements in the priority queue. The queue does
390*e7776783SApple OSS Distributions  *              not maintain its invariants while getting destroyed. The priority queue and
391*e7776783SApple OSS Distributions  *              the linkage nodes need to be re-initialized before re-using them.
392*e7776783SApple OSS Distributions  *      Header:
393*e7776783SApple OSS Distributions  *              priority_queue_destroy(pq, type, field, callback)
394*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
395*e7776783SApple OSS Distributions  *                      <callback> callback for each element
396*e7776783SApple OSS Distributions  *
397*e7776783SApple OSS Distributions  *      Returns:
398*e7776783SApple OSS Distributions  *              None
399*e7776783SApple OSS Distributions  */
400*e7776783SApple OSS Distributions #define priority_queue_destroy(pq, type, field, callback)                       \
401*e7776783SApple OSS Distributions MACRO_BEGIN                                                                     \
402*e7776783SApple OSS Distributions 	void (^__callback)(type *) = (callback); /* type check */               \
403*e7776783SApple OSS Distributions 	_priority_queue_destroy(pq, offsetof(type, field),                      \
404*e7776783SApple OSS Distributions 	    (void (^)(void *))(__callback));                                    \
405*e7776783SApple OSS Distributions MACRO_END
406*e7776783SApple OSS Distributions 
407*e7776783SApple OSS Distributions /*
408*e7776783SApple OSS Distributions  *      Macro:          priority_queue_min
409*e7776783SApple OSS Distributions  *      Function:
410*e7776783SApple OSS Distributions  *              Lookup the minimum in a min-priority queue.
411*e7776783SApple OSS Distributions  *
412*e7776783SApple OSS Distributions  *      Header:
413*e7776783SApple OSS Distributions  *              priority_queue_min(pq, type, field)
414*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
415*e7776783SApple OSS Distributions  *                      <type> type of element in priority queue
416*e7776783SApple OSS Distributions  *                      <field> chain field in (*<type>)
417*e7776783SApple OSS Distributions  *      Returns:
418*e7776783SApple OSS Distributions  *              <type *> root element
419*e7776783SApple OSS Distributions  */
420*e7776783SApple OSS Distributions #define priority_queue_min(pq, type, field) ({                                  \
421*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_min_heap(pq), "queue is min heap");     \
422*e7776783SApple OSS Distributions 	pqe_element((pq)->pq_root, type, field);                                \
423*e7776783SApple OSS Distributions })
424*e7776783SApple OSS Distributions 
425*e7776783SApple OSS Distributions /*
426*e7776783SApple OSS Distributions  *      Macro:          priority_queue_max
427*e7776783SApple OSS Distributions  *      Function:
428*e7776783SApple OSS Distributions  *              Lookup the maximum element in a max-priority queue.
429*e7776783SApple OSS Distributions  *
430*e7776783SApple OSS Distributions  *      Header:
431*e7776783SApple OSS Distributions  *              priority_queue_max(pq, type, field)
432*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
433*e7776783SApple OSS Distributions  *                      <type> type of element in priority queue
434*e7776783SApple OSS Distributions  *                      <field> chain field in (*<type>)
435*e7776783SApple OSS Distributions  *      Returns:
436*e7776783SApple OSS Distributions  *              <type *> root element
437*e7776783SApple OSS Distributions  */
438*e7776783SApple OSS Distributions #define priority_queue_max(pq, type, field) ({                                  \
439*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_max_heap(pq), "queue is max heap");     \
440*e7776783SApple OSS Distributions 	pqe_element((pq)->pq_root, type, field);                                \
441*e7776783SApple OSS Distributions })
442*e7776783SApple OSS Distributions 
443*e7776783SApple OSS Distributions /*
444*e7776783SApple OSS Distributions  *      Macro:          priority_queue_insert
445*e7776783SApple OSS Distributions  *      Function:
446*e7776783SApple OSS Distributions  *              Insert an element into the priority queue
447*e7776783SApple OSS Distributions  *
448*e7776783SApple OSS Distributions  *              The caller must have set the key prio to insertion
449*e7776783SApple OSS Distributions  *
450*e7776783SApple OSS Distributions  *      Header:
451*e7776783SApple OSS Distributions  *              priority_queue_insert(pq, elt, new_key)
452*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
453*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> elt
454*e7776783SApple OSS Distributions  *      Returns:
455*e7776783SApple OSS Distributions  *              Whether the inserted element became the new root
456*e7776783SApple OSS Distributions  */
457*e7776783SApple OSS Distributions extern bool
458*e7776783SApple OSS Distributions priority_queue_insert(struct priority_queue *pq,
459*e7776783SApple OSS Distributions     struct priority_queue_entry *elt) __pqueue_overloadable;
460*e7776783SApple OSS Distributions 
461*e7776783SApple OSS Distributions /*
462*e7776783SApple OSS Distributions  *      Macro:          priority_queue_remove_min
463*e7776783SApple OSS Distributions  *      Function:
464*e7776783SApple OSS Distributions  *              Remove the minimum element in a min-heap priority queue.
465*e7776783SApple OSS Distributions  *      Header:
466*e7776783SApple OSS Distributions  *              priority_queue_remove_min(pq, type, field)
467*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
468*e7776783SApple OSS Distributions  *                      <type> type of element in priority queue
469*e7776783SApple OSS Distributions  *                      <field> chain field in (*<type>)
470*e7776783SApple OSS Distributions  *      Returns:
471*e7776783SApple OSS Distributions  *              <type *> max element
472*e7776783SApple OSS Distributions  */
473*e7776783SApple OSS Distributions #define priority_queue_remove_min(pq, type, field) ({                           \
474*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_min_heap(pq), "queue is min heap");     \
475*e7776783SApple OSS Distributions 	pqe_element(_priority_queue_remove_root(pq), type, field);              \
476*e7776783SApple OSS Distributions })
477*e7776783SApple OSS Distributions 
478*e7776783SApple OSS Distributions /*
479*e7776783SApple OSS Distributions  *      Macro:          priority_queue_remove_max
480*e7776783SApple OSS Distributions  *      Function:
481*e7776783SApple OSS Distributions  *              Remove the maximum element in a max-heap priority queue.
482*e7776783SApple OSS Distributions  *      Header:
483*e7776783SApple OSS Distributions  *              priority_queue_remove_max(pq, type, field)
484*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
485*e7776783SApple OSS Distributions  *                      <type> type of element in priority queue
486*e7776783SApple OSS Distributions  *                      <field> chain field in (*<type>)
487*e7776783SApple OSS Distributions  *      Returns:
488*e7776783SApple OSS Distributions  *              <type *> max element
489*e7776783SApple OSS Distributions  */
490*e7776783SApple OSS Distributions #define priority_queue_remove_max(pq, type, field) ({                           \
491*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_max_heap(pq), "queue is max heap");     \
492*e7776783SApple OSS Distributions 	pqe_element(_priority_queue_remove_root(pq), type, field);              \
493*e7776783SApple OSS Distributions })
494*e7776783SApple OSS Distributions 
495*e7776783SApple OSS Distributions /*
496*e7776783SApple OSS Distributions  *      Macro:          priority_queue_remove
497*e7776783SApple OSS Distributions  *      Function:
498*e7776783SApple OSS Distributions  *              Removes an element from the priority queue
499*e7776783SApple OSS Distributions  *      Header:
500*e7776783SApple OSS Distributions  *              priority_queue_remove(pq, elt)
501*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
502*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> elt
503*e7776783SApple OSS Distributions  *      Returns:
504*e7776783SApple OSS Distributions  *              Whether the removed element was the root
505*e7776783SApple OSS Distributions  */
506*e7776783SApple OSS Distributions extern bool
507*e7776783SApple OSS Distributions priority_queue_remove(struct priority_queue *pq,
508*e7776783SApple OSS Distributions     struct priority_queue_entry *elt) __pqueue_overloadable;
509*e7776783SApple OSS Distributions 
510*e7776783SApple OSS Distributions 
511*e7776783SApple OSS Distributions /*
512*e7776783SApple OSS Distributions  *      Macro:          priority_queue_entry_decreased
513*e7776783SApple OSS Distributions  *
514*e7776783SApple OSS Distributions  *      Function:
515*e7776783SApple OSS Distributions  *              Signal the priority queue that the entry priority has decreased.
516*e7776783SApple OSS Distributions  *
517*e7776783SApple OSS Distributions  *              The new value for the element priority must have been set
518*e7776783SApple OSS Distributions  *              prior to calling this function.
519*e7776783SApple OSS Distributions  *
520*e7776783SApple OSS Distributions  *      Header:
521*e7776783SApple OSS Distributions  *              priority_queue_entry_decreased(pq, elt)
522*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
523*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> elt
524*e7776783SApple OSS Distributions  *      Returns:
525*e7776783SApple OSS Distributions  *              Whether the update caused the root or its key to change.
526*e7776783SApple OSS Distributions  */
527*e7776783SApple OSS Distributions extern bool
528*e7776783SApple OSS Distributions priority_queue_entry_decreased(struct priority_queue *pq,
529*e7776783SApple OSS Distributions     struct priority_queue_entry *elt) __pqueue_overloadable;
530*e7776783SApple OSS Distributions 
531*e7776783SApple OSS Distributions /*
532*e7776783SApple OSS Distributions  *      Macro:          priority_queue_entry_increased
533*e7776783SApple OSS Distributions  *
534*e7776783SApple OSS Distributions  *      Function:
535*e7776783SApple OSS Distributions  *              Signal the priority queue that the entry priority has increased.
536*e7776783SApple OSS Distributions  *
537*e7776783SApple OSS Distributions  *              The new value for the element priority must have been set
538*e7776783SApple OSS Distributions  *              prior to calling this function.
539*e7776783SApple OSS Distributions  *
540*e7776783SApple OSS Distributions  *      Header:
541*e7776783SApple OSS Distributions  *              priority_queue_entry_increased(pq, elt, new_key)
542*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
543*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> elt
544*e7776783SApple OSS Distributions  *      Returns:
545*e7776783SApple OSS Distributions  *              Whether the update caused the root or its key to change.
546*e7776783SApple OSS Distributions  */
547*e7776783SApple OSS Distributions extern bool
548*e7776783SApple OSS Distributions priority_queue_entry_increased(struct priority_queue *pq,
549*e7776783SApple OSS Distributions     struct priority_queue_entry *elt) __pqueue_overloadable;
550*e7776783SApple OSS Distributions 
551*e7776783SApple OSS Distributions 
552*e7776783SApple OSS Distributions #pragma mark priority_queue_sched_*
553*e7776783SApple OSS Distributions 
554*e7776783SApple OSS Distributions __enum_decl(priority_queue_entry_sched_modifier_t, uint8_t, {
555*e7776783SApple OSS Distributions 	PRIORITY_QUEUE_ENTRY_NONE      = 0,
556*e7776783SApple OSS Distributions 	PRIORITY_QUEUE_ENTRY_PREEMPTED = 1,
557*e7776783SApple OSS Distributions });
558*e7776783SApple OSS Distributions 
559*e7776783SApple OSS Distributions #define priority_queue_is_sched_heap(pq) _Generic(pq, \
560*e7776783SApple OSS Distributions 	struct priority_queue_sched_min *: true, \
561*e7776783SApple OSS Distributions 	struct priority_queue_sched_max *: true, \
562*e7776783SApple OSS Distributions 	struct priority_queue_sched_stable_min *: true, \
563*e7776783SApple OSS Distributions 	struct priority_queue_sched_stable_max *: true, \
564*e7776783SApple OSS Distributions 	default: false)
565*e7776783SApple OSS Distributions 
566*e7776783SApple OSS Distributions /*
567*e7776783SApple OSS Distributions  *      Macro:          priority_queue_entry_set_sched_pri
568*e7776783SApple OSS Distributions  *
569*e7776783SApple OSS Distributions  *      Function:
570*e7776783SApple OSS Distributions  *              Sets the scheduler priority on an entry supporting this concept.
571*e7776783SApple OSS Distributions  *
572*e7776783SApple OSS Distributions  *              The priority is expected to fit on 8 bits.
573*e7776783SApple OSS Distributions  *              An optional sorting modifier.
574*e7776783SApple OSS Distributions  *
575*e7776783SApple OSS Distributions  *      Header:
576*e7776783SApple OSS Distributions  *              priority_queue_entry_set_sched_pri(pq, elt, pri, modifier)
577*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
578*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> elt
579*e7776783SApple OSS Distributions  *                      <uint8_t> pri
580*e7776783SApple OSS Distributions  *                      <priority_queue_entry_sched_modifier_t> modifier
581*e7776783SApple OSS Distributions  */
582*e7776783SApple OSS Distributions #define priority_queue_entry_set_sched_pri(pq, elt, pri, modifier)              \
583*e7776783SApple OSS Distributions MACRO_BEGIN                                                                     \
584*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_sched_heap(pq), "is a sched heap");     \
585*e7776783SApple OSS Distributions 	(elt)->key = (priority_queue_key_t)(((pri) << 8) + (modifier));         \
586*e7776783SApple OSS Distributions MACRO_END
587*e7776783SApple OSS Distributions 
588*e7776783SApple OSS Distributions /*
589*e7776783SApple OSS Distributions  *      Macro:          priority_queue_entry_sched_pri
590*e7776783SApple OSS Distributions  *
591*e7776783SApple OSS Distributions  *      Function:
592*e7776783SApple OSS Distributions  *              Return the scheduler priority on an entry supporting this
593*e7776783SApple OSS Distributions  *              concept.
594*e7776783SApple OSS Distributions  *
595*e7776783SApple OSS Distributions  *      Header:
596*e7776783SApple OSS Distributions  *              priority_queue_entry_sched_pri(pq, elt)
597*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
598*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> elt
599*e7776783SApple OSS Distributions  *
600*e7776783SApple OSS Distributions  *      Returns:
601*e7776783SApple OSS Distributions  *              The scheduler priority of this entry
602*e7776783SApple OSS Distributions  */
603*e7776783SApple OSS Distributions #define priority_queue_entry_sched_pri(pq, elt) ({                              \
604*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_sched_heap(pq), "is a sched heap");     \
605*e7776783SApple OSS Distributions 	(priority_queue_key_t)((elt)->key >> 8);                                \
606*e7776783SApple OSS Distributions })
607*e7776783SApple OSS Distributions 
608*e7776783SApple OSS Distributions /*
609*e7776783SApple OSS Distributions  *      Macro:          priority_queue_entry_sched_modifier
610*e7776783SApple OSS Distributions  *
611*e7776783SApple OSS Distributions  *      Function:
612*e7776783SApple OSS Distributions  *              Return the scheduler modifier on an entry supporting this
613*e7776783SApple OSS Distributions  *              concept.
614*e7776783SApple OSS Distributions  *
615*e7776783SApple OSS Distributions  *      Header:
616*e7776783SApple OSS Distributions  *              priority_queue_entry_sched_modifier(pq, elt)
617*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
618*e7776783SApple OSS Distributions  *                      <priority_queue_entry_t> elt
619*e7776783SApple OSS Distributions  *
620*e7776783SApple OSS Distributions  *      Returns:
621*e7776783SApple OSS Distributions  *              The scheduler priority of this entry
622*e7776783SApple OSS Distributions  */
623*e7776783SApple OSS Distributions #define priority_queue_entry_sched_modifier(pq, elt) ({                         \
624*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_sched_heap(pq), "is a sched heap");     \
625*e7776783SApple OSS Distributions 	(priority_queue_entry_sched_modifier_t)(elt)->key;                      \
626*e7776783SApple OSS Distributions })
627*e7776783SApple OSS Distributions 
628*e7776783SApple OSS Distributions /*
629*e7776783SApple OSS Distributions  *      Macro:          priority_queue_min_sched_pri
630*e7776783SApple OSS Distributions  *
631*e7776783SApple OSS Distributions  *      Function:
632*e7776783SApple OSS Distributions  *              Return the scheduler priority of the minimum element
633*e7776783SApple OSS Distributions  *              of a scheduler priority queue.
634*e7776783SApple OSS Distributions  *
635*e7776783SApple OSS Distributions  *      Header:
636*e7776783SApple OSS Distributions  *              priority_queue_min_sched_pri(pq)
637*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
638*e7776783SApple OSS Distributions  *
639*e7776783SApple OSS Distributions  *      Returns:
640*e7776783SApple OSS Distributions  *              The scheduler priority of this entry
641*e7776783SApple OSS Distributions  */
642*e7776783SApple OSS Distributions #define priority_queue_min_sched_pri(pq) ({                                     \
643*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_min_heap(pq), "queue is min heap");     \
644*e7776783SApple OSS Distributions 	priority_queue_entry_sched_pri(pq, (pq)->pq_root);                      \
645*e7776783SApple OSS Distributions })
646*e7776783SApple OSS Distributions 
647*e7776783SApple OSS Distributions /*
648*e7776783SApple OSS Distributions  *      Macro:          priority_queue_max_sched_pri
649*e7776783SApple OSS Distributions  *
650*e7776783SApple OSS Distributions  *      Function:
651*e7776783SApple OSS Distributions  *              Return the scheduler priority of the maximum element
652*e7776783SApple OSS Distributions  *              of a scheduler priority queue.
653*e7776783SApple OSS Distributions  *
654*e7776783SApple OSS Distributions  *      Header:
655*e7776783SApple OSS Distributions  *              priority_queue_max_sched_pri(pq)
656*e7776783SApple OSS Distributions  *                      <struct priority_queue *> pq
657*e7776783SApple OSS Distributions  *
658*e7776783SApple OSS Distributions  *      Returns:
659*e7776783SApple OSS Distributions  *              The scheduler priority of this entry
660*e7776783SApple OSS Distributions  */
661*e7776783SApple OSS Distributions #define priority_queue_max_sched_pri(pq) ({                                     \
662*e7776783SApple OSS Distributions 	static_assert(priority_queue_is_max_heap(pq), "queue is max heap");     \
663*e7776783SApple OSS Distributions 	priority_queue_entry_sched_pri(pq, (pq)->pq_root);                      \
664*e7776783SApple OSS Distributions })
665*e7776783SApple OSS Distributions 
666*e7776783SApple OSS Distributions 
667*e7776783SApple OSS Distributions #pragma mark implementation details
668*e7776783SApple OSS Distributions 
669*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_MAKE_BASE(pqueue_t, pqelem_t) \
670*e7776783SApple OSS Distributions                                                                                 \
671*e7776783SApple OSS Distributions __pqueue_overloadable extern void                                               \
672*e7776783SApple OSS Distributions _priority_queue_destroy(pqueue_t pq, uintptr_t offset, void (^cb)(void *));     \
673*e7776783SApple OSS Distributions                                                                                 \
674*e7776783SApple OSS Distributions __pqueue_overloadable extern bool                                               \
675*e7776783SApple OSS Distributions priority_queue_insert(pqueue_t que, pqelem_t elt);                              \
676*e7776783SApple OSS Distributions                                                                                 \
677*e7776783SApple OSS Distributions __pqueue_overloadable extern pqelem_t                                           \
678*e7776783SApple OSS Distributions _priority_queue_remove_root(pqueue_t que);                                      \
679*e7776783SApple OSS Distributions                                                                                 \
680*e7776783SApple OSS Distributions __pqueue_overloadable extern bool                                               \
681*e7776783SApple OSS Distributions priority_queue_remove(pqueue_t que, pqelem_t elt);                              \
682*e7776783SApple OSS Distributions                                                                                 \
683*e7776783SApple OSS Distributions __pqueue_overloadable extern bool                                               \
684*e7776783SApple OSS Distributions priority_queue_entry_decreased(pqueue_t que, pqelem_t elt);                     \
685*e7776783SApple OSS Distributions                                                                                 \
686*e7776783SApple OSS Distributions __pqueue_overloadable extern bool                                               \
687*e7776783SApple OSS Distributions priority_queue_entry_increased(pqueue_t que, pqelem_t elt)
688*e7776783SApple OSS Distributions 
689*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_MAKE(pqueue_t, pqelem_t) \
690*e7776783SApple OSS Distributions __pqueue_overloadable                                                           \
691*e7776783SApple OSS Distributions static inline void                                                              \
692*e7776783SApple OSS Distributions priority_queue_init(pqueue_t que)                                               \
693*e7776783SApple OSS Distributions {                                                                               \
694*e7776783SApple OSS Distributions 	__builtin_bzero(que, sizeof(*que));                                     \
695*e7776783SApple OSS Distributions }                                                                               \
696*e7776783SApple OSS Distributions                                                                                 \
697*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE_BASE(pqueue_t, pqelem_t)
698*e7776783SApple OSS Distributions 
699*e7776783SApple OSS Distributions #define PRIORITY_QUEUE_MAKE_CB(pqueue_t, pqelem_t) \
700*e7776783SApple OSS Distributions __pqueue_overloadable                                                           \
701*e7776783SApple OSS Distributions static inline void                                                              \
702*e7776783SApple OSS Distributions priority_queue_init(pqueue_t pq, priority_queue_compare_fn_t cmp_fn)            \
703*e7776783SApple OSS Distributions {                                                                               \
704*e7776783SApple OSS Distributions 	pq->pq_root = NULL;                                                     \
705*e7776783SApple OSS Distributions 	pq->pq_cmp_fn = cmp_fn;                                                 \
706*e7776783SApple OSS Distributions }                                                                               \
707*e7776783SApple OSS Distributions                                                                                 \
708*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE_BASE(pqueue_t, pqelem_t)
709*e7776783SApple OSS Distributions 
710*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE_CB(struct priority_queue_min *, priority_queue_entry_t);
711*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE_CB(struct priority_queue_max *, priority_queue_entry_t);
712*e7776783SApple OSS Distributions 
713*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE(struct priority_queue_deadline_min *, priority_queue_entry_deadline_t);
714*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE(struct priority_queue_deadline_max *, priority_queue_entry_deadline_t);
715*e7776783SApple OSS Distributions 
716*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE(struct priority_queue_sched_min *, priority_queue_entry_sched_t);
717*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE(struct priority_queue_sched_max *, priority_queue_entry_sched_t);
718*e7776783SApple OSS Distributions 
719*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE(struct priority_queue_sched_stable_min *, priority_queue_entry_stable_t);
720*e7776783SApple OSS Distributions PRIORITY_QUEUE_MAKE(struct priority_queue_sched_stable_max *, priority_queue_entry_stable_t);
721*e7776783SApple OSS Distributions 
722*e7776783SApple OSS Distributions __END_DECLS
723*e7776783SApple OSS Distributions 
724*e7776783SApple OSS Distributions #pragma GCC visibility pop
725*e7776783SApple OSS Distributions 
726*e7776783SApple OSS Distributions #endif /* _KERN_PRIORITY_QUEUE_H_ */
727