1 /* 2 * Copyright 2016 Advanced Micro Devices, Inc. 3 * All Rights Reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining 6 * a copy of this software and associated documentation files (the 7 * "Software"), to deal in the Software without restriction, including 8 * without limitation the rights to use, copy, modify, merge, publish, 9 * distribute, sub license, and/or sell copies of the Software, and to 10 * permit persons to whom the Software is furnished to do so, subject to 11 * the following conditions: 12 * 13 * The above copyright notice and this permission notice (including the 14 * next paragraph) shall be included in all copies or substantial portions 15 * of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 19 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 20 * NON-INFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS, AUTHORS 21 * AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 23 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 24 * USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 */ 27 28 /** 29 * \file 30 * 31 * Helper library for carving out smaller allocations (called "(slab) entries") 32 * from larger buffers (called "slabs"). 33 * 34 * The library supports maintaining separate heaps (e.g. VRAM vs. GTT). The 35 * meaning of each heap is treated as opaque by this library. 36 * 37 * The library allows delaying the re-use of an entry, i.e. an entry may be 38 * freed by calling \ref pb_slab_free even while the corresponding buffer 39 * region is still in use by the GPU. A callback function is called to 40 * determine when it is safe to allocate the entry again; the user of this 41 * library is expected to maintain the required fences or similar. 42 */ 43 44 #ifndef PB_SLAB_H 45 #define PB_SLAB_H 46 47 #include "pb_buffer.h" 48 #include "util/list.h" 49 #include "os/os_thread.h" 50 51 struct pb_slab; 52 struct pb_slabs; 53 struct pb_slab_group; 54 55 /* Descriptor of a slab entry. 56 * 57 * The user of this utility library is expected to embed this in a larger 58 * structure that describes a buffer object. 59 */ 60 struct pb_slab_entry 61 { 62 struct list_head head; 63 struct pb_slab *slab; /* the slab that contains this buffer */ 64 unsigned group_index; /* index into pb_slabs::groups */ 65 }; 66 67 /* Descriptor of a slab from which many entries are carved out. 68 * 69 * The user of this utility library is expected to embed this in a larger 70 * structure that describes a buffer object. 71 */ 72 struct pb_slab 73 { 74 struct list_head head; 75 76 struct list_head free; /* list of free pb_slab_entry structures */ 77 unsigned num_free; /* number of entries in free list */ 78 unsigned num_entries; /* total number of entries */ 79 }; 80 81 /* Callback function that is called when a new slab needs to be allocated 82 * for fulfilling allocation requests of the given size from the given heap. 83 * 84 * The callback must allocate a pb_slab structure and the desired number 85 * of entries. All entries that belong to the slab must be added to the free 86 * list. Entries' pb_slab_entry structures must be initialized with the given 87 * group_index. 88 * 89 * The callback may call pb_slab functions. 90 */ 91 typedef struct pb_slab *(slab_alloc_fn)(void *priv, 92 unsigned heap, 93 unsigned entry_size, 94 unsigned group_index); 95 96 /* Callback function that is called when all entries of a slab have been freed. 97 * 98 * The callback must free the slab and all its entries. It must not call any of 99 * the pb_slab functions, or a deadlock (recursive mutex lock) may occur. 100 */ 101 typedef void (slab_free_fn)(void *priv, struct pb_slab *); 102 103 /* Callback function to determine whether a given entry can already be reused. 104 */ 105 typedef bool (slab_can_reclaim_fn)(void *priv, struct pb_slab_entry *); 106 107 /* Manager of slab allocations. The user of this utility library should embed 108 * this in a structure somewhere and call pb_slab_init/deinit at init/shutdown 109 * time. 110 */ 111 struct pb_slabs 112 { 113 mtx_t mutex; 114 115 unsigned min_order; 116 unsigned num_orders; 117 unsigned num_heaps; 118 119 /* One group per (heap, order) pair. */ 120 struct pb_slab_group *groups; 121 122 /* List of entries waiting to be reclaimed, i.e. they have been passed to 123 * pb_slab_free, but may not be safe for re-use yet. The tail points at 124 * the most-recently freed entry. 125 */ 126 struct list_head reclaim; 127 128 void *priv; 129 slab_can_reclaim_fn *can_reclaim; 130 slab_alloc_fn *slab_alloc; 131 slab_free_fn *slab_free; 132 }; 133 134 struct pb_slab_entry * 135 pb_slab_alloc(struct pb_slabs *slabs, unsigned size, unsigned heap); 136 137 void 138 pb_slab_free(struct pb_slabs* slabs, struct pb_slab_entry *entry); 139 140 void 141 pb_slabs_reclaim(struct pb_slabs *slabs); 142 143 bool 144 pb_slabs_init(struct pb_slabs *slabs, 145 unsigned min_order, unsigned max_order, 146 unsigned num_heaps, 147 void *priv, 148 slab_can_reclaim_fn *can_reclaim, 149 slab_alloc_fn *slab_alloc, 150 slab_free_fn *slab_free); 151 152 void 153 pb_slabs_deinit(struct pb_slabs *slabs); 154 155 #endif 156