1/*
2 * Copyright 2010-2015 Samy Al Bahra.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#ifndef CK_HP_H
28#define CK_HP_H
29
30#include <ck_cc.h>
31#include <ck_md.h>
32#include <ck_pr.h>
33#include <ck_stack.h>
34
35#ifndef CK_HP_CACHE
36#define CK_HP_CACHE 512
37#endif
38
39struct ck_hp_hazard;
40typedef void (*ck_hp_destructor_t)(void *);
41
42struct ck_hp {
43	ck_stack_t subscribers;
44	unsigned int n_subscribers;
45	unsigned int n_free;
46	unsigned int threshold;
47	unsigned int degree;
48	ck_hp_destructor_t destroy;
49};
50typedef struct ck_hp ck_hp_t;
51
52struct ck_hp_hazard {
53	void *pointer;
54	void *data;
55	ck_stack_entry_t pending_entry;
56};
57typedef struct ck_hp_hazard ck_hp_hazard_t;
58
59enum {
60	CK_HP_USED = 0,
61	CK_HP_FREE = 1
62};
63
64struct ck_hp_record {
65	int state;
66	void **pointers;
67	void *cache[CK_HP_CACHE];
68	struct ck_hp *global;
69	ck_stack_t pending;
70	unsigned int n_pending;
71	ck_stack_entry_t global_entry;
72	unsigned int n_peak;
73	uint64_t n_reclamations;
74} CK_CC_CACHELINE;
75typedef struct ck_hp_record ck_hp_record_t;
76
77CK_CC_INLINE static void
78ck_hp_set(struct ck_hp_record *record, unsigned int i, void *pointer)
79{
80
81	ck_pr_store_ptr(&record->pointers[i], pointer);
82	return;
83}
84
85CK_CC_INLINE static void
86ck_hp_set_fence(struct ck_hp_record *record, unsigned int i, void *pointer)
87{
88
89#ifdef CK_MD_TSO
90	ck_pr_fas_ptr(&record->pointers[i], pointer);
91#else
92	ck_pr_store_ptr(&record->pointers[i], pointer);
93	ck_pr_fence_memory();
94#endif
95
96	return;
97}
98
99CK_CC_INLINE static void
100ck_hp_clear(struct ck_hp_record *record)
101{
102	void **pointers = record->pointers;
103	unsigned int i;
104
105	for (i = 0; i < record->global->degree; i++)
106		*pointers++ = NULL;
107
108	return;
109}
110
111void ck_hp_init(ck_hp_t *, unsigned int, unsigned int, ck_hp_destructor_t);
112void ck_hp_set_threshold(ck_hp_t *, unsigned int);
113void ck_hp_register(ck_hp_t *, ck_hp_record_t *, void **);
114void ck_hp_unregister(ck_hp_record_t *);
115ck_hp_record_t *ck_hp_recycle(ck_hp_t *);
116void ck_hp_reclaim(ck_hp_record_t *);
117void ck_hp_free(ck_hp_record_t *, ck_hp_hazard_t *, void *, void *);
118void ck_hp_retire(ck_hp_record_t *, ck_hp_hazard_t *, void *, void *);
119void ck_hp_purge(ck_hp_record_t *);
120
121#endif /* CK_HP_H */
122