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_STACK_H
28#define CK_HP_STACK_H
29
30#include <ck_cc.h>
31#include <ck_hp.h>
32#include <ck_pr.h>
33#include <ck_stack.h>
34#include <ck_stddef.h>
35
36#define CK_HP_STACK_SLOTS_COUNT 1
37#define CK_HP_STACK_SLOTS_SIZE  sizeof(void *)
38
39CK_CC_INLINE static void
40ck_hp_stack_push_mpmc(struct ck_stack *target, struct ck_stack_entry *entry)
41{
42
43	ck_stack_push_upmc(target, entry);
44	return;
45}
46
47CK_CC_INLINE static bool
48ck_hp_stack_trypush_mpmc(struct ck_stack *target, struct ck_stack_entry *entry)
49{
50
51	return ck_stack_trypush_upmc(target, entry);
52}
53
54CK_CC_INLINE static struct ck_stack_entry *
55ck_hp_stack_pop_mpmc(ck_hp_record_t *record, struct ck_stack *target)
56{
57	struct ck_stack_entry *entry, *update;
58
59	do {
60		entry = ck_pr_load_ptr(&target->head);
61		if (entry == NULL)
62			return NULL;
63
64		ck_hp_set_fence(record, 0, entry);
65	} while (entry != ck_pr_load_ptr(&target->head));
66
67	while (ck_pr_cas_ptr_value(&target->head, entry, entry->next, &entry) == false) {
68		if (entry == NULL)
69			return NULL;
70
71		ck_hp_set_fence(record, 0, entry);
72
73		update = ck_pr_load_ptr(&target->head);
74		while (entry != update) {
75			ck_hp_set_fence(record, 0, update);
76			entry = update;
77			update = ck_pr_load_ptr(&target->head);
78			if (update == NULL)
79				return NULL;
80		}
81	}
82
83	return entry;
84}
85
86CK_CC_INLINE static bool
87ck_hp_stack_trypop_mpmc(ck_hp_record_t *record, struct ck_stack *target, struct ck_stack_entry **r)
88{
89	struct ck_stack_entry *entry;
90
91	entry = ck_pr_load_ptr(&target->head);
92	if (entry == NULL)
93		return false;
94
95	ck_hp_set_fence(record, 0, entry);
96	if (entry != ck_pr_load_ptr(&target->head))
97		goto leave;
98
99	if (ck_pr_cas_ptr_value(&target->head, entry, entry->next, &entry) == false)
100		goto leave;
101
102	*r = entry;
103	return true;
104
105leave:
106	ck_hp_set(record, 0, NULL);
107	return false;
108}
109
110#endif /* CK_HP_STACK_H */
111