xref: /freebsd/sys/dev/isci/scil/sci_pool.h (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
3  *
4  * This file is provided under a dual BSD/GPLv2 license.  When using or
5  * redistributing this file, you may do so under either license.
6  *
7  * GPL LICENSE SUMMARY
8  *
9  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of version 2 of the GNU General Public License as
13  * published by the Free Software Foundation.
14  *
15  * This program is distributed in the hope that it will be useful, but
16  * WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
23  * The full GNU General Public License is included in this distribution
24  * in the file called LICENSE.GPL.
25  *
26  * BSD LICENSE
27  *
28  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
29  * All rights reserved.
30  *
31  * Redistribution and use in source and binary forms, with or without
32  * modification, are permitted provided that the following conditions
33  * are met:
34  *
35  *   * Redistributions of source code must retain the above copyright
36  *     notice, this list of conditions and the following disclaimer.
37  *   * Redistributions in binary form must reproduce the above copyright
38  *     notice, this list of conditions and the following disclaimer in
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40  *     distribution.
41  *
42  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
43  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
44  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
45  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
46  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
47  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
48  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
49  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
50  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
51  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
52  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
53  */
54 /**
55  * @file
56  *
57  * @brief This file contains the interface to the pool class.
58  *        This class allows two different two different priority tasks to
59  *        insert and remove items from the free pool. The user of the pool
60  *        is expected to evaluate the pool condition empty before a get
61  *        operation and pool condition full before a put operation.
62  *        Methods Provided:
63  *        - sci_pool_create()
64  *        - sci_pool_initialize()
65  *        - sci_pool_empty()
66  *        - sci_pool_full()
67  *        - sci_pool_get()
68  *        - sci_pool_put()
69  */
70 
71 #ifndef _SCI_POOL_H_
72 #define _SCI_POOL_H_
73 
74 #include <dev/isci/types.h>
75 
76 /**
77  * Private operation for the pool
78  */
79 #define SCI_POOL_INCREMENT(this_pool, index) \
80   (((index) + 1) == (this_pool).size ? 0 : (index) + 1)
81 
82 /**
83  * This creates a pool structure of pool_name. The members in the pool are
84  * of type with number of elements equal to size.
85  */
86 #define SCI_POOL_CREATE(pool_name, type, pool_size) \
87 struct \
88 { \
89    U32 size; \
90    U32 get; \
91    U32 put; \
92    type array[(pool_size) + 1]; \
93 } pool_name
94 
95 
96 /**
97  * This macro evaluates the pool and returns TRUE if the pool is empty.
98  * If the pool is empty the user should not perform any get operation on
99  * the pool.
100  */
101 #define sci_pool_empty(this_pool) \
102    ((this_pool).get == (this_pool).put)
103 
104 /**
105  * This macro evaluates the pool and returns TRUE if the pool is full.  If
106  * the pool is full the user should not perform any put operation.
107  */
108 #define sci_pool_full(this_pool) \
109    (SCI_POOL_INCREMENT(this_pool, (this_pool).put) == (this_pool).get)
110 
111 /**
112  * This macro returns the size of the pool created.  The internal size
113  * of the pool is actually 1 larger then necessary in order to ensure
114  * get and put pointers can be written simultaneously by different
115  * users.  As a result, this macro subtracts 1 from the internal size
116  */
117 #define sci_pool_size(this_pool) \
118    ((this_pool).size - 1)
119 
120 /**
121  * This macro indicates the number of elements currently contained in the
122  * pool.
123  */
124 #define sci_pool_count(this_pool) \
125    ( \
126       sci_pool_empty((this_pool)) \
127       ? 0 \
128       : ( \
129            sci_pool_full((this_pool)) \
130            ? sci_pool_size((this_pool)) \
131            : ( \
132                 (this_pool).get > (this_pool).put \
133                 ? ((this_pool).size - (this_pool).get + (this_pool).put) \
134                 : ((this_pool).put - (this_pool).get) \
135              ) \
136         ) \
137    )
138 
139 /**
140  * This macro initializes the pool to an empty condition.
141  */
142 #define sci_pool_initialize(this_pool) \
143 { \
144    (this_pool).size = (sizeof((this_pool).array) / sizeof((this_pool).array[0])); \
145    (this_pool).get = 0; \
146    (this_pool).put = 0; \
147 }
148 
149 /**
150  * This macro will get the next free element from the pool.
151  * This should only be called if the pool is not empty.
152  */
153 #define sci_pool_get(this_pool, my_value) \
154 { \
155    (my_value) = (this_pool).array[(this_pool).get]; \
156    (this_pool).get = SCI_POOL_INCREMENT((this_pool), (this_pool).get); \
157 }
158 
159 /**
160  * This macro will put the value into the pool.
161  * This should only be called if the pool is not full.
162  */
163 #define sci_pool_put(this_pool, the_value) \
164 { \
165    (this_pool).array[(this_pool).put] = (the_value); \
166    (this_pool).put = SCI_POOL_INCREMENT((this_pool), (this_pool).put); \
167 }
168 
169 /**
170  * This macro will search the pool and remove any elements in the pool
171  * matching the supplied value.
172  * @note This method can only be utilized on pools
173  */
174 #define sci_pool_erase(this_pool, type, the_value) \
175 { \
176    type tmp_value; \
177    U32 index; \
178    U32 element_count = sci_pool_count((this_pool)); \
179  \
180    for (index = 0; index < element_count; index++) \
181    { \
182       sci_pool_get((this_pool), tmp_value); \
183       if (tmp_value != (the_value)) \
184          sci_pool_put((this_pool), tmp_value); \
185    } \
186 }
187 
188 #endif // _SCI_POOL_H_
189