xref: /freebsd/sys/sys/pctrie.h (revision 3b7ffacd)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2013 EMC Corp.
5  * Copyright (c) 2011 Jeffrey Roberson <jeff@freebsd.org>
6  * Copyright (c) 2008 Mayur Shardul <mayur.shardul@gmail.com>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #ifndef _SYS_PCTRIE_H_
32 #define _SYS_PCTRIE_H_
33 
34 #include <sys/_pctrie.h>
35 #include <sys/_smr.h>
36 
37 #ifdef _KERNEL
38 
39 #define	PCTRIE_DEFINE_SMR(name, type, field, allocfn, freefn, smr)	\
40     PCTRIE_DEFINE(name, type, field, allocfn, freefn)			\
41 									\
42 static __inline struct type *						\
43 name##_PCTRIE_LOOKUP_UNLOCKED(struct pctrie *ptree, uint64_t key)	\
44 {									\
45 									\
46 	return name##_PCTRIE_VAL2PTR(pctrie_lookup_unlocked(ptree,	\
47 	    key, (smr)));						\
48 }									\
49 
50 #define	PCTRIE_DEFINE(name, type, field, allocfn, freefn)		\
51 									\
52 CTASSERT(sizeof(((struct type *)0)->field) == sizeof(uint64_t));	\
53 /*									\
54  * XXX This assert protects flag bits, it does not enforce natural	\
55  * alignment.  32bit architectures do not naturally align 64bit fields.	\
56  */									\
57 CTASSERT((__offsetof(struct type, field) & (sizeof(uint32_t) - 1)) == 0); \
58 									\
59 static __inline struct type *						\
60 name##_PCTRIE_VAL2PTR(uint64_t *val)					\
61 {									\
62 									\
63 	if (val == NULL)						\
64 		return (NULL);						\
65 	return (struct type *)						\
66 	    ((uintptr_t)val - __offsetof(struct type, field));		\
67 }									\
68 									\
69 static __inline uint64_t *						\
70 name##_PCTRIE_PTR2VAL(struct type *ptr)					\
71 {									\
72 									\
73 	return &ptr->field;						\
74 }									\
75 									\
76 static __inline int							\
77 name##_PCTRIE_INSERT(struct pctrie *ptree, struct type *ptr)		\
78 {									\
79 	struct pctrie_node *parent;					\
80 	void *parentp;							\
81 	uint64_t *val = name##_PCTRIE_PTR2VAL(ptr);			\
82 									\
83 	parentp = pctrie_insert_lookup(ptree, val);			\
84 	if (parentp == NULL)						\
85 		return (0);						\
86 	parent = allocfn(ptree);					\
87 	if (parent == NULL)						\
88 		return (ENOMEM);					\
89 	pctrie_insert_node(parentp, parent, val);			\
90 	return (0);							\
91 }									\
92 									\
93 static __inline __unused struct type *					\
94 name##_PCTRIE_LOOKUP(struct pctrie *ptree, uint64_t key)		\
95 {									\
96 									\
97 	return name##_PCTRIE_VAL2PTR(pctrie_lookup(ptree, key));	\
98 }									\
99 									\
100 static __inline __unused struct type *					\
101 name##_PCTRIE_LOOKUP_LE(struct pctrie *ptree, uint64_t key)		\
102 {									\
103 									\
104 	return name##_PCTRIE_VAL2PTR(pctrie_lookup_le(ptree, key));	\
105 }									\
106 									\
107 static __inline __unused struct type *					\
108 name##_PCTRIE_LOOKUP_GE(struct pctrie *ptree, uint64_t key)		\
109 {									\
110 									\
111 	return name##_PCTRIE_VAL2PTR(pctrie_lookup_ge(ptree, key));	\
112 }									\
113 									\
114 static __inline __unused void						\
115 name##_PCTRIE_RECLAIM(struct pctrie *ptree)				\
116 {									\
117 	struct pctrie_node *freenode, *node;				\
118 									\
119 	for (freenode = pctrie_reclaim_begin(&node, ptree);		\
120 	    freenode != NULL;						\
121 	    freenode = pctrie_reclaim_resume(&node))			\
122 		freefn(ptree, freenode);				\
123 }									\
124 									\
125 static __inline __unused struct type *					\
126 name##_PCTRIE_REPLACE(struct pctrie *ptree, struct type *ptr)		\
127 {									\
128 									\
129 	return name##_PCTRIE_VAL2PTR(					\
130 	    pctrie_replace(ptree, name##_PCTRIE_PTR2VAL(ptr)));		\
131 }									\
132 									\
133 static __inline __unused void						\
134 name##_PCTRIE_REMOVE(struct pctrie *ptree, uint64_t key)		\
135 {									\
136 	uint64_t *val;							\
137 	struct pctrie_node *freenode;					\
138 									\
139 	val = pctrie_remove_lookup(ptree, key, &freenode);		\
140 	if (val == NULL)						\
141 		panic("%s: key not found", __func__);			\
142 	if (freenode != NULL)						\
143 		freefn(ptree, freenode);				\
144 }									\
145 									\
146 static __inline __unused struct type *					\
147 name##_PCTRIE_REMOVE_LOOKUP(struct pctrie *ptree, uint64_t key)		\
148 {									\
149 	uint64_t *val;							\
150 	struct pctrie_node *freenode;					\
151 									\
152 	val = pctrie_remove_lookup(ptree, key, &freenode);		\
153 	if (freenode != NULL)						\
154 		freefn(ptree, freenode);				\
155 	return name##_PCTRIE_VAL2PTR(val);				\
156 }
157 
158 void		*pctrie_insert_lookup(struct pctrie *ptree, uint64_t *val);
159 void		pctrie_insert_node(void *parentp,
160 		    struct pctrie_node *parent, uint64_t *val);
161 uint64_t	*pctrie_lookup(struct pctrie *ptree, uint64_t key);
162 uint64_t	*pctrie_lookup_ge(struct pctrie *ptree, uint64_t key);
163 uint64_t	*pctrie_lookup_le(struct pctrie *ptree, uint64_t key);
164 uint64_t	*pctrie_lookup_unlocked(struct pctrie *ptree, uint64_t key,
165 		    smr_t smr);
166 struct pctrie_node *pctrie_reclaim_begin(struct pctrie_node **pnode,
167 		    struct pctrie *ptree);
168 struct pctrie_node *pctrie_reclaim_resume(struct pctrie_node **pnode);
169 uint64_t	*pctrie_remove_lookup(struct pctrie *ptree, uint64_t index,
170 		    struct pctrie_node **killnode);
171 uint64_t	*pctrie_replace(struct pctrie *ptree, uint64_t *newval);
172 size_t		pctrie_node_size(void);
173 int		pctrie_zone_init(void *mem, int size, int flags);
174 
175 /*
176  * Each search path in the trie terminates at a leaf, which is a pointer to a
177  * value marked with a set 1-bit.  A leaf may be associated with a null pointer
178  * to indicate no value there.
179  */
180 #define	PCTRIE_ISLEAF	0x1
181 #define PCTRIE_NULL (struct pctrie_node *)PCTRIE_ISLEAF
182 
183 static __inline void
pctrie_init(struct pctrie * ptree)184 pctrie_init(struct pctrie *ptree)
185 {
186 	ptree->pt_root = PCTRIE_NULL;
187 }
188 
189 static __inline bool
pctrie_is_empty(struct pctrie * ptree)190 pctrie_is_empty(struct pctrie *ptree)
191 {
192 	return (ptree->pt_root == PCTRIE_NULL);
193 }
194 
195 /* Set of all flag bits stored in node pointers. */
196 #define	PCTRIE_FLAGS	(PCTRIE_ISLEAF)
197 /* Minimum align parameter for uma_zcreate. */
198 #define	PCTRIE_PAD	PCTRIE_FLAGS
199 
200 /*
201  * These widths should allow the pointers to a node's children to fit within
202  * a single cache line.  The extra levels from a narrow width should not be
203  * a problem thanks to path compression.
204  */
205 #ifdef __LP64__
206 #define	PCTRIE_WIDTH	4
207 #else
208 #define	PCTRIE_WIDTH	3
209 #endif
210 
211 #define	PCTRIE_COUNT	(1 << PCTRIE_WIDTH)
212 
213 #endif /* _KERNEL */
214 #endif /* !_SYS_PCTRIE_H_ */
215