diff options
| -rw-r--r-- | src/gallium/auxiliary/util/u_cache.c | 40 |
1 files changed, 35 insertions, 5 deletions
diff --git a/src/gallium/auxiliary/util/u_cache.c b/src/gallium/auxiliary/util/u_cache.c index acc82bac0ff..c748cb99dd0 100644 --- a/src/gallium/auxiliary/util/u_cache.c +++ b/src/gallium/auxiliary/util/u_cache.c @@ -73,19 +73,29 @@ struct util_cache /** Destroy a (key, value) pair */ void (*destroy)(void *key, void *value); + /** Max entries in the cache */ uint32_t size; + /** Array [size] of entries */ struct util_cache_entry *entries; + /** Number of entries in the cache */ unsigned count; + + /** Head of list, sorted from Least-recently used to Most-recently used */ struct util_cache_entry lru; }; + static void ensure_sanity(const struct util_cache *cache); #define CACHE_DEFAULT_ALPHA 2 +/** + * Create a new cache with 'size' entries. Also provide functions for + * hashing keys, comparing keys and destroying (key,value) pairs. + */ struct util_cache * util_cache_create(uint32_t (*hash)(const void *key), int (*compare)(const void *key1, const void *key2), @@ -108,7 +118,7 @@ util_cache_create(uint32_t (*hash)(const void *key), cache->size = size; cache->entries = CALLOC(size, sizeof(struct util_cache_entry)); - if(!cache->entries) { + if (!cache->entries) { FREE(cache); return NULL; } @@ -118,6 +128,9 @@ util_cache_create(uint32_t (*hash)(const void *key), } +/** + * Try to find a cache entry, given the key and hash of the key. + */ static struct util_cache_entry * util_cache_entry_get(struct util_cache *cache, uint32_t hash, @@ -169,7 +182,7 @@ util_cache_entry_destroy(struct util_cache *cache, remove_from_list(entry); cache->count--; - if(cache->destroy) + if (cache->destroy) cache->destroy(key, value); entry->state = DELETED; @@ -177,6 +190,9 @@ util_cache_entry_destroy(struct util_cache *cache, } +/** + * Insert an entry in the cache, given the key and value. + */ void util_cache_set(struct util_cache *cache, void *key, @@ -213,6 +229,10 @@ util_cache_set(struct util_cache *cache, } +/** + * Search the cache for an entry with the given key. Return the corresponding + * value or NULL if not found. + */ void * util_cache_get(struct util_cache *cache, const void *key) @@ -235,6 +255,10 @@ util_cache_get(struct util_cache *cache, } +/** + * Remove all entries from the cache. The 'destroy' function will be called + * for each entry's (key, value). + */ void util_cache_clear(struct util_cache *cache) { @@ -244,7 +268,7 @@ util_cache_clear(struct util_cache *cache) if (!cache) return; - for(i = 0; i < cache->size; ++i) { + for (i = 0; i < cache->size; ++i) { util_cache_entry_destroy(cache, &cache->entries[i]); cache->entries[i].state = EMPTY; } @@ -255,6 +279,9 @@ util_cache_clear(struct util_cache *cache) } +/** + * Destroy the cache and all entries. + */ void util_cache_destroy(struct util_cache *cache) { @@ -263,12 +290,12 @@ util_cache_destroy(struct util_cache *cache) return; #ifdef DEBUG - if(cache->count >= 20*cache->size) { + if (cache->count >= 20*cache->size) { /* Normal approximation of the Poisson distribution */ double mean = (double)cache->count/(double)cache->size; double stddev = sqrt(mean); unsigned i; - for(i = 0; i < cache->size; ++i) { + for (i = 0; i < cache->size; ++i) { double z = fabs(cache->entries[i].count - mean)/stddev; /* This assert should not fail 99.9999998027% of the times, unless * the hash function is a poor one */ @@ -284,6 +311,9 @@ util_cache_destroy(struct util_cache *cache) } +/** + * Remove the cache entry which matches the given key. + */ void util_cache_remove(struct util_cache *cache, const void *key) |