X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=lib%2Flibrte_hash%2Frte_cuckoo_hash.c;h=87a4c01f2f9eb64ace1afa210894aba7603ddd56;hb=fbda9f1459271435df3ea2575ca5845d04733466;hp=a3ac2feadd45b6e18edd8daa0f458ce94a256295;hpb=4d9ca3ed213320eaef0d8a7e95b3b00c2d70800b;p=dpdk.git

diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
index a3ac2feadd..87a4c01f2f 100644
--- a/lib/librte_hash/rte_cuckoo_hash.c
+++ b/lib/librte_hash/rte_cuckoo_hash.c
@@ -570,7 +570,6 @@ __hash_rw_reader_unlock(const struct rte_hash *h)
 void
 rte_hash_reset(struct rte_hash *h)
 {
-	void *ptr;
 	uint32_t tot_ring_cnt, i;
 
 	if (h == NULL)
@@ -581,16 +580,14 @@ rte_hash_reset(struct rte_hash *h)
 	memset(h->key_store, 0, h->key_entry_size * (h->entries + 1));
 	*h->tbl_chng_cnt = 0;
 
-	/* clear the free ring */
-	while (rte_ring_dequeue(h->free_slots, &ptr) == 0)
-		continue;
+	/* reset the free ring */
+	rte_ring_reset(h->free_slots);
 
-	/* clear free extendable bucket ring and memory */
+	/* flush free extendable bucket ring and memory */
 	if (h->ext_table_support) {
 		memset(h->buckets_ext, 0, h->num_buckets *
 						sizeof(struct rte_hash_bucket));
-		while (rte_ring_dequeue(h->free_ext_bkts, &ptr) == 0)
-			continue;
+		rte_ring_reset(h->free_ext_bkts);
 	}
 
 	/* Repopulate the free slots ring. Entry zero is reserved for key misses */
@@ -650,9 +647,11 @@ search_and_update(const struct rte_hash *h, void *data, const void *key,
 			k = (struct rte_hash_key *) ((char *)keys +
 					bkt->key_idx[i] * h->key_entry_size);
 			if (rte_hash_cmp_eq(key, k->key, h) == 0) {
-				/* 'pdata' acts as the synchronization point
-				 * when an existing hash entry is updated.
-				 * Key is not updated in this case.
+				/* The store to application data at *data
+				 * should not leak after the store to pdata
+				 * in the key store. i.e. pdata is the guard
+				 * variable. Release the application data
+				 * to the readers.
 				 */
 				__atomic_store_n(&k->pdata,
 					data,
@@ -712,11 +711,10 @@ rte_hash_cuckoo_insert_mw(const struct rte_hash *h,
 		/* Check if slot is available */
 		if (likely(prim_bkt->key_idx[i] == EMPTY_SLOT)) {
 			prim_bkt->sig_current[i] = sig;
-			/* Key can be of arbitrary length, so it is
-			 * not possible to store it atomically.
-			 * Hence the new key element's memory stores
-			 * (key as well as data) should be complete
-			 * before it is referenced.
+			/* Store to signature and key should not
+			 * leak after the store to key_idx. i.e.
+			 * key_idx is the guard variable for signature
+			 * and key.
 			 */
 			__atomic_store_n(&prim_bkt->key_idx[i],
 					 new_idx,
@@ -991,17 +989,15 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 
 	new_k = RTE_PTR_ADD(keys, (uintptr_t)slot_id * h->key_entry_size);
 	new_idx = (uint32_t)((uintptr_t) slot_id);
-	/* Copy key */
-	memcpy(new_k->key, key, h->key_len);
-	/* Key can be of arbitrary length, so it is not possible to store
-	 * it atomically. Hence the new key element's memory stores
-	 * (key as well as data) should be complete before it is referenced.
-	 * 'pdata' acts as the synchronization point when an existing hash
-	 * entry is updated.
+	/* The store to application data (by the application) at *data should
+	 * not leak after the store of pdata in the key store. i.e. pdata is
+	 * the guard variable. Release the application data to the readers.
 	 */
 	__atomic_store_n(&new_k->pdata,
 		data,
 		__ATOMIC_RELEASE);
+	/* Copy key */
+	memcpy(new_k->key, key, h->key_len);
 
 	/* Find an empty slot and insert */
 	ret = rte_hash_cuckoo_insert_mw(h, prim_bkt, sec_bkt, key, data,
@@ -1065,8 +1061,10 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 			/* Check if slot is available */
 			if (likely(cur_bkt->key_idx[i] == EMPTY_SLOT)) {
 				cur_bkt->sig_current[i] = short_sig;
-				/* Store to signature should not leak after
-				 * the store to key_idx
+				/* Store to signature and key should not
+				 * leak after the store to key_idx. i.e.
+				 * key_idx is the guard variable for signature
+				 * and key.
 				 */
 				__atomic_store_n(&cur_bkt->key_idx[i],
 						 new_idx,
@@ -1088,8 +1086,9 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 	bkt_id = (uint32_t)((uintptr_t)ext_bkt_id) - 1;
 	/* Use the first location of the new bucket */
 	(h->buckets_ext[bkt_id]).sig_current[0] = short_sig;
-	/* Store to signature should not leak after
-	 * the store to key_idx
+	/* Store to signature and key should not leak after
+	 * the store to key_idx. i.e. key_idx is the guard variable
+	 * for signature and key.
 	 */
 	__atomic_store_n(&(h->buckets_ext[bkt_id]).key_idx[0],
 			 new_idx,
@@ -1185,7 +1184,6 @@ search_one_bucket_lf(const struct rte_hash *h, const void *key, uint16_t sig,
 {
 	int i;
 	uint32_t key_idx;
-	void *pdata;
 	struct rte_hash_key *k, *keys = h->key_store;
 
 	for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
@@ -1202,12 +1200,13 @@ search_one_bucket_lf(const struct rte_hash *h, const void *key, uint16_t sig,
 			if (key_idx != EMPTY_SLOT) {
 				k = (struct rte_hash_key *) ((char *)keys +
 						key_idx * h->key_entry_size);
-				pdata = __atomic_load_n(&k->pdata,
-						__ATOMIC_ACQUIRE);
 
 				if (rte_hash_cmp_eq(key, k->key, h) == 0) {
-					if (data != NULL)
-						*data = pdata;
+					if (data != NULL) {
+						*data = __atomic_load_n(
+							&k->pdata,
+							__ATOMIC_ACQUIRE);
+					}
 					/*
 					 * Return index where key is stored,
 					 * subtracting the first dummy index
@@ -1905,7 +1904,6 @@ __rte_hash_lookup_bulk_lf(const struct rte_hash *h, const void **keys,
 	uint32_t prim_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
 	uint32_t sec_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
 	struct rte_hash_bucket *cur_bkt, *next_bkt;
-	void *pdata[RTE_HASH_LOOKUP_BULK_MAX];
 	uint32_t cnt_b, cnt_a;
 
 	/* Prefetch first keys */
@@ -2007,10 +2005,6 @@ __rte_hash_lookup_bulk_lf(const struct rte_hash *h, const void **keys,
 					(const char *)h->key_store +
 					key_idx * h->key_entry_size);
 
-				if (key_idx != EMPTY_SLOT)
-					pdata[i] = __atomic_load_n(
-							&key_slot->pdata,
-							__ATOMIC_ACQUIRE);
 				/*
 				 * If key index is 0, do not compare key,
 				 * as it is checking the dummy slot
@@ -2019,7 +2013,9 @@ __rte_hash_lookup_bulk_lf(const struct rte_hash *h, const void **keys,
 					!rte_hash_cmp_eq(
 						key_slot->key, keys[i], h)) {
 					if (data != NULL)
-						data[i] = pdata[i];
+						data[i] = __atomic_load_n(
+							&key_slot->pdata,
+							__ATOMIC_ACQUIRE);
 
 					hits |= 1ULL << i;
 					positions[i] = key_idx - 1;
@@ -2041,10 +2037,6 @@ __rte_hash_lookup_bulk_lf(const struct rte_hash *h, const void **keys,
 					(const char *)h->key_store +
 					key_idx * h->key_entry_size);
 
-				if (key_idx != EMPTY_SLOT)
-					pdata[i] = __atomic_load_n(
-							&key_slot->pdata,
-							__ATOMIC_ACQUIRE);
 				/*
 				 * If key index is 0, do not compare key,
 				 * as it is checking the dummy slot
@@ -2054,7 +2046,9 @@ __rte_hash_lookup_bulk_lf(const struct rte_hash *h, const void **keys,
 					!rte_hash_cmp_eq(
 						key_slot->key, keys[i], h)) {
 					if (data != NULL)
-						data[i] = pdata[i];
+						data[i] = __atomic_load_n(
+							&key_slot->pdata,
+							__ATOMIC_ACQUIRE);
 
 					hits |= 1ULL << i;
 					positions[i] = key_idx - 1;