xref: /wlan-driver/qca-wifi-host-cmn/qdf/inc/qdf_flex_mem.h (revision 5113495b16420b49004c444715d2daae2066e7dc)
1*5113495bSYour Name /*
2*5113495bSYour Name  * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
3*5113495bSYour Name  * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
4*5113495bSYour Name  *
5*5113495bSYour Name  * Permission to use, copy, modify, and/or distribute this software for
6*5113495bSYour Name  * any purpose with or without fee is hereby granted, provided that the
7*5113495bSYour Name  * above copyright notice and this permission notice appear in all
8*5113495bSYour Name  * copies.
9*5113495bSYour Name  *
10*5113495bSYour Name  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
11*5113495bSYour Name  * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
12*5113495bSYour Name  * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
13*5113495bSYour Name  * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
14*5113495bSYour Name  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
15*5113495bSYour Name  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
16*5113495bSYour Name  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17*5113495bSYour Name  * PERFORMANCE OF THIS SOFTWARE.
18*5113495bSYour Name  */
19*5113495bSYour Name 
20*5113495bSYour Name /**
21*5113495bSYour Name  * DOC: qdf_flex_mem (flexibly sized memory allocator)
22*5113495bSYour Name  * QCA driver framework (QDF) flex mem APIs
23*5113495bSYour Name  *
24*5113495bSYour Name  * A flex memory allocator is a memory pool which not only dynamically expands,
25*5113495bSYour Name  * but also dynamically reduces as well. Benefits over full dynamic memory
26*5113495bSYour Name  * allocation are amoritized allocation cost, and reduced memory fragmentation.
27*5113495bSYour Name  *
28*5113495bSYour Name  * The allocator consists of 3 parts: the pool, segments, and items. Items are
29*5113495bSYour Name  * the smallest chunks of memory that are handed out via the alloc call, and
30*5113495bSYour Name  * are all of a uniform size. Segments are groups of items, representing the
31*5113495bSYour Name  * smallest amount of memory that can be dynamically allocated or freed. A pool
32*5113495bSYour Name  * is simply a collection of segments.
33*5113495bSYour Name  */
34*5113495bSYour Name 
35*5113495bSYour Name #ifndef __QDF_FLEX_MEM_H
36*5113495bSYour Name #define __QDF_FLEX_MEM_H
37*5113495bSYour Name 
38*5113495bSYour Name #include "qdf_list.h"
39*5113495bSYour Name #include "qdf_lock.h"
40*5113495bSYour Name 
41*5113495bSYour Name #define QDF_FM_BITMAP uint32_t
42*5113495bSYour Name #define QDF_FM_BITMAP_BITS (sizeof(QDF_FM_BITMAP) * 8)
43*5113495bSYour Name 
44*5113495bSYour Name /**
45*5113495bSYour Name  * struct qdf_flex_mem_pool - a pool of memory segments
46*5113495bSYour Name  * @seg_list: the list containing the memory segments
47*5113495bSYour Name  * @lock: spinlock for protecting internal data structures
48*5113495bSYour Name  * @reduction_limit: the minimum number of segments to keep during reduction
49*5113495bSYour Name  * @item_size: the size of the items the pool will allocate
50*5113495bSYour Name  */
51*5113495bSYour Name struct qdf_flex_mem_pool {
52*5113495bSYour Name 	qdf_list_t seg_list;
53*5113495bSYour Name 	struct qdf_spinlock lock;
54*5113495bSYour Name 	uint16_t reduction_limit;
55*5113495bSYour Name 	uint16_t item_size;
56*5113495bSYour Name };
57*5113495bSYour Name 
58*5113495bSYour Name /**
59*5113495bSYour Name  * struct qdf_flex_mem_segment - a memory pool segment
60*5113495bSYour Name  * @node: the list node for membership in the memory pool
61*5113495bSYour Name  * @dynamic: true if this segment was dynamically allocated
62*5113495bSYour Name  * @used_bitmap: bitmap for tracking which items in the segment are in use
63*5113495bSYour Name  * @bytes: raw memory for allocating items from
64*5113495bSYour Name  */
65*5113495bSYour Name struct qdf_flex_mem_segment {
66*5113495bSYour Name 	qdf_list_node_t node;
67*5113495bSYour Name 	bool dynamic;
68*5113495bSYour Name 	QDF_FM_BITMAP used_bitmap;
69*5113495bSYour Name 	uint8_t *bytes;
70*5113495bSYour Name };
71*5113495bSYour Name 
72*5113495bSYour Name /**
73*5113495bSYour Name  * DEFINE_QDF_FLEX_MEM_POOL() - define a new flex mem pool with one segment
74*5113495bSYour Name  * @name: the name of the pool variable
75*5113495bSYour Name  * @size_of_item: size of the items the pool will allocate
76*5113495bSYour Name  * @rm_limit: min number of segments to keep during reduction
77*5113495bSYour Name  */
78*5113495bSYour Name #define DEFINE_QDF_FLEX_MEM_POOL(name, size_of_item, rm_limit) \
79*5113495bSYour Name 	struct qdf_flex_mem_pool name; \
80*5113495bSYour Name 	uint8_t __ ## name ## _head_bytes[QDF_FM_BITMAP_BITS * (size_of_item)];\
81*5113495bSYour Name 	struct qdf_flex_mem_segment __ ## name ## _head = { \
82*5113495bSYour Name 		.node = QDF_LIST_NODE_INIT_SINGLE( \
83*5113495bSYour Name 			QDF_LIST_ANCHOR(name.seg_list)), \
84*5113495bSYour Name 		.bytes = __ ## name ## _head_bytes, \
85*5113495bSYour Name 	}; \
86*5113495bSYour Name 	struct qdf_flex_mem_pool name = { \
87*5113495bSYour Name 		.seg_list = QDF_LIST_INIT_SINGLE(__ ## name ## _head.node), \
88*5113495bSYour Name 		.reduction_limit = (rm_limit), \
89*5113495bSYour Name 		.item_size = (size_of_item), \
90*5113495bSYour Name 	}
91*5113495bSYour Name 
92*5113495bSYour Name /**
93*5113495bSYour Name  * qdf_flex_mem_init() - initialize a qdf_flex_mem_pool
94*5113495bSYour Name  * @pool: the pool to initialize
95*5113495bSYour Name  *
96*5113495bSYour Name  * Return: None
97*5113495bSYour Name  */
98*5113495bSYour Name void qdf_flex_mem_init(struct qdf_flex_mem_pool *pool);
99*5113495bSYour Name 
100*5113495bSYour Name /**
101*5113495bSYour Name  * qdf_flex_mem_deinit() - deinitialize a qdf_flex_mem_pool
102*5113495bSYour Name  * @pool: the pool to deinitialize
103*5113495bSYour Name  *
104*5113495bSYour Name  * Return: None
105*5113495bSYour Name  */
106*5113495bSYour Name void qdf_flex_mem_deinit(struct qdf_flex_mem_pool *pool);
107*5113495bSYour Name 
108*5113495bSYour Name /**
109*5113495bSYour Name  * qdf_flex_mem_alloc() - logically allocate memory from the pool
110*5113495bSYour Name  * @pool: the pool to allocate from
111*5113495bSYour Name  *
112*5113495bSYour Name  * This function returns any unused item from any existing segment in the pool.
113*5113495bSYour Name  * If there are no unused items in the pool, a new segment is dynamically
114*5113495bSYour Name  * allocated to service the request. The size of the allocated memory is the
115*5113495bSYour Name  * size originally used to create the pool.
116*5113495bSYour Name  *
117*5113495bSYour Name  * Return: Point to newly allocated memory, NULL on failure
118*5113495bSYour Name  */
119*5113495bSYour Name void *qdf_flex_mem_alloc(struct qdf_flex_mem_pool *pool);
120*5113495bSYour Name 
121*5113495bSYour Name /**
122*5113495bSYour Name  * qdf_flex_mem_free() - logically frees @ptr from the pool
123*5113495bSYour Name  * @pool: the pool to return the memory to
124*5113495bSYour Name  * @ptr: a pointer received via a call to qdf_flex_mem_alloc()
125*5113495bSYour Name  *
126*5113495bSYour Name  * This function marks the item corresponding to @ptr as unused. If that item
127*5113495bSYour Name  * was the last used item in the segment it belongs to, and the segment was
128*5113495bSYour Name  * dynamically allocated, the segment will be freed.
129*5113495bSYour Name  *
130*5113495bSYour Name  * Return: None
131*5113495bSYour Name  */
132*5113495bSYour Name void qdf_flex_mem_free(struct qdf_flex_mem_pool *pool, void *ptr);
133*5113495bSYour Name 
134*5113495bSYour Name #endif /* __QDF_FLEX_MEM_H */
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