diff options
| -rw-r--r-- | src/vppinfra/bihash_template.c | 27 | ||||
| -rw-r--r-- | src/vppinfra/bihash_template.h | 72 |
2 files changed, 58 insertions, 41 deletions
diff --git a/src/vppinfra/bihash_template.c b/src/vppinfra/bihash_template.c index e3a5759d766..b5eb379a0f5 100644 --- a/src/vppinfra/bihash_template.c +++ b/src/vppinfra/bihash_template.c @@ -135,8 +135,9 @@ BV (make_working_copy) (BVT (clib_bihash) * h, BVT (clib_bihash_bucket) * b) clib_mem_set_heap (oldheap); - /* Turn off the cache */ - BV (clib_bihash_cache_enable_disable) (b, 0); + /* Lock the bucket... */ + while (BV (clib_bihash_lock_bucket) (b) == 0) + ; v = BV (clib_bihash_get_value) (h, b->offset); @@ -416,7 +417,7 @@ expand_ok: unlock: BV (clib_bihash_reset_cache) (b); - BV (clib_bihash_cache_enable_disable) (b, 1 /* enable */ ); + BV (clib_bihash_unlock_bucket) (b); CLIB_MEMORY_BARRIER (); h->writer_lock[0] = 0; return rv; @@ -444,7 +445,7 @@ int BV (clib_bihash_search) return -1; /* Check the cache, if currently enabled */ - if (PREDICT_TRUE (b->cache_lru & (1 << 15))) + if (PREDICT_TRUE ((b->cache_lru & (1 << 15)) == 0)) { limit = BIHASH_KVP_CACHE_SIZE; kvp = b->cache; @@ -475,16 +476,16 @@ int BV (clib_bihash_search) *valuep = v->kvp[i]; /* Shut off the cache */ - BV (clib_bihash_cache_enable_disable) (b, 0); - CLIB_MEMORY_BARRIER (); - - cache_slot = BV (clib_bihash_get_lru) (b); - b->cache[cache_slot] = v->kvp[i]; - BV (clib_bihash_update_lru) (b, cache_slot); + if (BV (clib_bihash_lock_bucket) (b)) + { + cache_slot = BV (clib_bihash_get_lru) (b); + b->cache[cache_slot] = v->kvp[i]; + BV (clib_bihash_update_lru) (b, cache_slot); - /* Reenable the cache */ - BV (clib_bihash_cache_enable_disable) (b, 1); - h->cache_misses++; + /* Reenable the cache */ + BV (clib_bihash_unlock_bucket) (b); + h->cache_misses++; + } return 0; } } diff --git a/src/vppinfra/bihash_template.h b/src/vppinfra/bihash_template.h index feb6fb68797..3d9c59cb933 100644 --- a/src/vppinfra/bihash_template.h +++ b/src/vppinfra/bihash_template.h @@ -182,13 +182,29 @@ static inline void BV (clib_bihash_reset_cache) (BVT (clib_bihash_bucket) * b) b->cache_lru = initial_lru_value; } -static inline void BV (clib_bihash_cache_enable_disable) - (BVT (clib_bihash_bucket) * b, u8 enable) +static inline int BV (clib_bihash_lock_bucket) (BVT (clib_bihash_bucket) * b) { BVT (clib_bihash_bucket) tmp_b; + u64 rv; + + tmp_b.as_u64 = 0; + tmp_b.cache_lru = 1 << 15; + + rv = __sync_fetch_and_or (&b->as_u64, tmp_b.as_u64); + tmp_b.as_u64 = rv; + /* Was already locked? */ + if (tmp_b.cache_lru & (1 << 15)) + return 0; + return 1; +} + +static inline void BV (clib_bihash_unlock_bucket) + (BVT (clib_bihash_bucket) * b) +{ + BVT (clib_bihash_bucket) tmp_b; + tmp_b.as_u64 = b->as_u64; - tmp_b.cache_lru &= 0x7FFF; - tmp_b.cache_lru |= enable << 15; + tmp_b.cache_lru &= ~(1 << 15); b->as_u64 = tmp_b.as_u64; } @@ -249,8 +265,8 @@ static inline int BV (clib_bihash_search_inline) if (b->offset == 0) return -1; - /* Check the cache, if currently enabled */ - if (PREDICT_TRUE (b->cache_lru & (1 << 15))) + /* Check the cache, if not currently locked */ + if (PREDICT_TRUE ((b->cache_lru & (1 << 15)) == 0)) { limit = BIHASH_KVP_CACHE_SIZE; kvp = b->cache; @@ -282,17 +298,17 @@ static inline int BV (clib_bihash_search_inline) u8 cache_slot; *key_result = v->kvp[i]; - /* Shut off the cache */ - BV (clib_bihash_cache_enable_disable) (b, 0); - CLIB_MEMORY_BARRIER (); - - cache_slot = BV (clib_bihash_get_lru) (b); - b->cache[cache_slot] = v->kvp[i]; - BV (clib_bihash_update_lru) (b, cache_slot); + /* Try to lock the bucket */ + if (BV (clib_bihash_lock_bucket) (b)) + { + cache_slot = BV (clib_bihash_get_lru) (b); + b->cache[cache_slot] = v->kvp[i]; + BV (clib_bihash_update_lru) (b, cache_slot); - /* Reenable the cache */ - BV (clib_bihash_cache_enable_disable) (b, 1); - h->cache_misses++; + /* Unlock the bucket */ + BV (clib_bihash_unlock_bucket) (b); + h->cache_misses++; + } return 0; } } @@ -320,8 +336,8 @@ static inline int BV (clib_bihash_search_inline_2) if (b->offset == 0) return -1; - /* Check the cache, if currently enabled */ - if (PREDICT_TRUE (b->cache_lru & (1 << 15))) + /* Check the cache, if currently unlocked */ + if (PREDICT_TRUE ((b->cache_lru & (1 << 15)) == 0)) { limit = BIHASH_KVP_CACHE_SIZE; kvp = b->cache; @@ -352,17 +368,17 @@ static inline int BV (clib_bihash_search_inline_2) u8 cache_slot; *valuep = v->kvp[i]; - /* Shut off the cache */ - BV (clib_bihash_cache_enable_disable) (b, 0); - CLIB_MEMORY_BARRIER (); - - cache_slot = BV (clib_bihash_get_lru) (b); - b->cache[cache_slot] = v->kvp[i]; - BV (clib_bihash_update_lru) (b, cache_slot); + /* Try to lock the bucket */ + if (BV (clib_bihash_lock_bucket) (b)) + { + cache_slot = BV (clib_bihash_get_lru) (b); + b->cache[cache_slot] = v->kvp[i]; + BV (clib_bihash_update_lru) (b, cache_slot); - /* Reenable the cache */ - BV (clib_bihash_cache_enable_disable) (b, 1); - h->cache_misses++; + /* Reenable the cache */ + BV (clib_bihash_unlock_bucket) (b); + h->cache_misses++; + } return 0; } } |