src/util/disk_cache.h

   1 /*
   2  * Copyright © 2014 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 #ifndef DISK_CACHE_H
  25 #define DISK_CACHE_H
  26
  27 #ifdef ENABLE_SHADER_CACHE
  28 #include <dlfcn.h>
  29 #endif
  30 #include <stdint.h>
  31 #include <stdbool.h>
  32 #include <sys/stat.h>
  33
  34 #ifdef __cplusplus
  35 extern "C" {
  36 #endif
  37
  38 /* Size of cache keys in bytes. */
  39 #define CACHE_KEY_SIZE 20
  40
  41 typedef uint8_t cache_key[CACHE_KEY_SIZE];
  42
  43 struct disk_cache;
  44
  45 static inline bool
  46 disk_cache_get_function_timestamp(void *ptr, uint32_t* timestamp)
  47 {
  48 #ifdef ENABLE_SHADER_CACHE
  49    Dl_info info;
  50    struct stat st;
  51    if (!dladdr(ptr, &info) || !info.dli_fname) {
  52       return false;
  53    }
  54    if (stat(info.dli_fname, &st)) {
  55       return false;
  56    }
  57    *timestamp = st.st_mtime;
  58    return true;
  59 #else
  60    return false;
  61 #endif
  62 }
  63
  64 /* Provide inlined stub functions if the shader cache is disabled. */
  65
  66 #ifdef ENABLE_SHADER_CACHE
  67
  68 /**
  69  * Create a new cache object.
  70  *
  71  * This function creates the handle necessary for all subsequent cache_*
  72  * functions.
  73  *
  74  * This cache provides two distinct operations:
  75  *
  76  *   o Storage and retrieval of arbitrary objects by cryptographic
  77  *     name (or "key").  This is provided via disk_cache_put() and
  78  *     disk_cache_get().
  79  *
  80  *   o The ability to store a key alone and check later whether the
  81  *     key was previously stored. This is provided via disk_cache_put_key()
  82  *     and disk_cache_has_key().
  83  *
  84  * The put_key()/has_key() operations are conceptually identical to
  85  * put()/get() with no data, but are provided separately to allow for
  86  * a more efficient implementation.
  87  *
  88  * In all cases, the keys are sequences of 20 bytes. It is anticipated
  89  * that callers will compute appropriate SHA-1 signatures for keys,
  90  * (though nothing in this implementation directly relies on how the
  91  * names are computed). See mesa-sha1.h and _mesa_sha1_compute for
  92  * assistance in computing SHA-1 signatures.
  93  */
  94 struct disk_cache *
  95 disk_cache_create(const char *gpu_name, const char *timestamp);
  96
  97 /**
  98  * Destroy a cache object, (freeing all associated resources).
  99  */
 100 void
 101 disk_cache_destroy(struct disk_cache *cache);
 102
 103 /**
 104  * Remove the item in the cache under the name \key.
 105  */
 106 void
 107 disk_cache_remove(struct disk_cache *cache, const cache_key key);
 108
 109 /**
 110  * Store an item in the cache under the name \key.
 111  *
 112  * The item can be retrieved later with disk_cache_get(), (unless the item has
 113  * been evicted in the interim).
 114  *
 115  * Any call to disk_cache_put() may cause an existing, random item to be
 116  * evicted from the cache.
 117  */
 118 void
 119 disk_cache_put(struct disk_cache *cache, const cache_key key,
 120                const void *data, size_t size);
 121
 122 /**
 123  * Retrieve an item previously stored in the cache with the name <key>.
 124  *
 125  * The item must have been previously stored with a call to disk_cache_put().
 126  *
 127  * If \size is non-NULL, then, on successful return, it will be set to the
 128  * size of the object.
 129  *
 130  * \return A pointer to the stored object if found. NULL if the object
 131  * is not found, or if any error occurs, (memory allocation failure,
 132  * filesystem error, etc.). The returned data is malloc'ed so the
 133  * caller should call free() it when finished.
 134  */
 135 void *
 136 disk_cache_get(struct disk_cache *cache, const cache_key key, size_t *size);
 137
 138 /**
 139  * Store the name \key within the cache, (without any associated data).
 140  *
 141  * Later this key can be checked with disk_cache_has_key(), (unless the key
 142  * has been evicted in the interim).
 143  *
 144  * Any call to cache_record() may cause an existing, random key to be
 145  * evicted from the cache.
 146  */
 147 void
 148 disk_cache_put_key(struct disk_cache *cache, const cache_key key);
 149
 150 /**
 151  * Test whether the name \key was previously recorded in the cache.
 152  *
 153  * Return value: True if disk_cache_put_key() was previously called with
 154  * \key, (and the key was not evicted in the interim).
 155  *
 156  * Note: disk_cache_has_key() will only return true for keys passed to
 157  * disk_cache_put_key(). Specifically, a call to disk_cache_put() will not cause
 158  * disk_cache_has_key() to return true for the same key.
 159  */
 160 bool
 161 disk_cache_has_key(struct disk_cache *cache, const cache_key key);
 162
 163 #else
 164
 165 static inline struct disk_cache *
 166 disk_cache_create(const char *gpu_name, const char *timestamp)
 167 {
 168    return NULL;
 169 }
 170
 171 static inline void
 172 disk_cache_destroy(struct disk_cache *cache) {
 173    return;
 174 }
 175
 176 static inline void
 177 disk_cache_put(struct disk_cache *cache, const cache_key key,
 178           const void *data, size_t size)
 179 {
 180    return;
 181 }
 182
 183 static inline void
 184 disk_cache_remove(struct disk_cache *cache, const cache_key key)
 185 {
 186    return;
 187 }
 188
 189 static inline uint8_t *
 190 disk_cache_get(struct disk_cache *cache, const cache_key key, size_t *size)
 191 {
 192    return NULL;
 193 }
 194
 195 static inline void
 196 disk_cache_put_key(struct disk_cache *cache, const cache_key key)
 197 {
 198    return;
 199 }
 200
 201 static inline bool
 202 disk_cache_has_key(struct disk_cache *cache, const cache_key key)
 203 {
 204    return false;
 205 }
 206
 207 #endif /* ENABLE_SHADER_CACHE */
 208
 209 #ifdef __cplusplus
 210 }
 211 #endif
 212
 213 #endif /* CACHE_H */