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 <assert.h>
  31 #include <stdint.h>
  32 #include <stdbool.h>
  33 #include <sys/stat.h>
  34
  35 #ifdef __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 /* Size of cache keys in bytes. */
  40 #define CACHE_KEY_SIZE 20
  41
  42 typedef uint8_t cache_key[CACHE_KEY_SIZE];
  43
  44 struct disk_cache;
  45
  46 static inline bool
  47 disk_cache_get_function_timestamp(void *ptr, uint32_t* timestamp)
  48 {
  49 #ifdef ENABLE_SHADER_CACHE
  50    Dl_info info;
  51    struct stat st;
  52    if (!dladdr(ptr, &info) || !info.dli_fname) {
  53       return false;
  54    }
  55    if (stat(info.dli_fname, &st)) {
  56       return false;
  57    }
  58    *timestamp = st.st_mtime;
  59    return true;
  60 #else
  61    return false;
  62 #endif
  63 }
  64
  65 /* Provide inlined stub functions if the shader cache is disabled. */
  66
  67 #ifdef ENABLE_SHADER_CACHE
  68
  69 /**
  70  * Create a new cache object.
  71  *
  72  * This function creates the handle necessary for all subsequent cache_*
  73  * functions.
  74  *
  75  * This cache provides two distinct operations:
  76  *
  77  *   o Storage and retrieval of arbitrary objects by cryptographic
  78  *     name (or "key").  This is provided via disk_cache_put() and
  79  *     disk_cache_get().
  80  *
  81  *   o The ability to store a key alone and check later whether the
  82  *     key was previously stored. This is provided via disk_cache_put_key()
  83  *     and disk_cache_has_key().
  84  *
  85  * The put_key()/has_key() operations are conceptually identical to
  86  * put()/get() with no data, but are provided separately to allow for
  87  * a more efficient implementation.
  88  *
  89  * In all cases, the keys are sequences of 20 bytes. It is anticipated
  90  * that callers will compute appropriate SHA-1 signatures for keys,
  91  * (though nothing in this implementation directly relies on how the
  92  * names are computed). See mesa-sha1.h and _mesa_sha1_compute for
  93  * assistance in computing SHA-1 signatures.
  94  */
  95 struct disk_cache *
  96 disk_cache_create(const char *gpu_name, const char *timestamp);
  97
  98 /**
  99  * Destroy a cache object, (freeing all associated resources).
 100  */
 101 void
 102 disk_cache_destroy(struct disk_cache *cache);
 103
 104 /**
 105  * Remove the item in the cache under the name \key.
 106  */
 107 void
 108 disk_cache_remove(struct disk_cache *cache, const cache_key key);
 109
 110 /**
 111  * Store an item in the cache under the name \key.
 112  *
 113  * The item can be retrieved later with disk_cache_get(), (unless the item has
 114  * been evicted in the interim).
 115  *
 116  * Any call to disk_cache_put() may cause an existing, random item to be
 117  * evicted from the cache.
 118  */
 119 void
 120 disk_cache_put(struct disk_cache *cache, const cache_key key,
 121                const void *data, size_t size);
 122
 123 /**
 124  * Retrieve an item previously stored in the cache with the name <key>.
 125  *
 126  * The item must have been previously stored with a call to disk_cache_put().
 127  *
 128  * If \size is non-NULL, then, on successful return, it will be set to the
 129  * size of the object.
 130  *
 131  * \return A pointer to the stored object if found. NULL if the object
 132  * is not found, or if any error occurs, (memory allocation failure,
 133  * filesystem error, etc.). The returned data is malloc'ed so the
 134  * caller should call free() it when finished.
 135  */
 136 void *
 137 disk_cache_get(struct disk_cache *cache, const cache_key key, size_t *size);
 138
 139 /**
 140  * Store the name \key within the cache, (without any associated data).
 141  *
 142  * Later this key can be checked with disk_cache_has_key(), (unless the key
 143  * has been evicted in the interim).
 144  *
 145  * Any call to cache_record() may cause an existing, random key to be
 146  * evicted from the cache.
 147  */
 148 void
 149 disk_cache_put_key(struct disk_cache *cache, const cache_key key);
 150
 151 /**
 152  * Test whether the name \key was previously recorded in the cache.
 153  *
 154  * Return value: True if disk_cache_put_key() was previously called with
 155  * \key, (and the key was not evicted in the interim).
 156  *
 157  * Note: disk_cache_has_key() will only return true for keys passed to
 158  * disk_cache_put_key(). Specifically, a call to disk_cache_put() will not cause
 159  * disk_cache_has_key() to return true for the same key.
 160  */
 161 bool
 162 disk_cache_has_key(struct disk_cache *cache, const cache_key key);
 163
 164 /**
 165  * Compute the name \key from \data of given \size.
 166  */
 167 void
 168 disk_cache_compute_key(struct disk_cache *cache, const void *data, size_t size,
 169                        cache_key key);
 170
 171 #else
 172
 173 static inline struct disk_cache *
 174 disk_cache_create(const char *gpu_name, const char *timestamp)
 175 {
 176    return NULL;
 177 }
 178
 179 static inline void
 180 disk_cache_destroy(struct disk_cache *cache) {
 181    return;
 182 }
 183
 184 static inline void
 185 disk_cache_put(struct disk_cache *cache, const cache_key key,
 186           const void *data, size_t size)
 187 {
 188    return;
 189 }
 190
 191 static inline void
 192 disk_cache_remove(struct disk_cache *cache, const cache_key key)
 193 {
 194    return;
 195 }
 196
 197 static inline uint8_t *
 198 disk_cache_get(struct disk_cache *cache, const cache_key key, size_t *size)
 199 {
 200    return NULL;
 201 }
 202
 203 static inline void
 204 disk_cache_put_key(struct disk_cache *cache, const cache_key key)
 205 {
 206    return;
 207 }
 208
 209 static inline bool
 210 disk_cache_has_key(struct disk_cache *cache, const cache_key key)
 211 {
 212    return false;
 213 }
 214
 215 static inline void
 216 disk_cache_compute_key(struct disk_cache *cache, const void *data, size_t size,
 217                        const cache_key key)
 218 {
 219    return;
 220 }
 221
 222 #endif /* ENABLE_SHADER_CACHE */
 223
 224 #ifdef __cplusplus
 225 }
 226 #endif
 227
 228 #endif /* CACHE_H */