From: Elza Mathew <elza.mathew@intel.com>
Date: Mon, 6 Nov 2017 18:04:02 +0000 (-0800)
Subject: hash: select cuckoo function at run-time
X-Git-Tag: spdx-start~135
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=3a47be9abbb64e44c85a689024a8de78a938e0c3;p=dpdk.git

hash: select cuckoo function at run-time

Compile-time function selection can potentially lead to
lower performance on generic builds done by distros.
Replaced compile time flag checks with run-time function
selection.

Signed-off-by: Elza Mathew <elza.mathew@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
---

diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
index 8bd3e6fc45..9b1387b5e8 100644
--- a/lib/librte_hash/rte_cuckoo_hash.c
+++ b/lib/librte_hash/rte_cuckoo_hash.c
@@ -95,6 +95,7 @@ rte_hash_create(const struct rte_hash_parameters *params)
 	unsigned num_key_slots;
 	unsigned hw_trans_mem_support = 0;
 	unsigned i;
+	rte_hash_function default_hash_func = (rte_hash_function)rte_jhash;
 
 	hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
 
@@ -238,6 +239,13 @@ rte_hash_create(const struct rte_hash_parameters *params)
 				RTE_CACHE_LINE_SIZE, params->socket_id);
 	}
 
+	/* Default hash function */
+#if defined(RTE_ARCH_X86)
+	default_hash_func = (rte_hash_function)rte_hash_crc;
+#elif defined(RTE_ARCH_ARM64)
+	if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_CRC32))
+		default_hash_func = (rte_hash_function)rte_hash_crc;
+#endif
 	/* Setup hash context */
 	snprintf(h->name, sizeof(h->name), "%s", params->name);
 	h->entries = params->entries;
@@ -249,7 +257,7 @@ rte_hash_create(const struct rte_hash_parameters *params)
 	h->bucket_bitmask = h->num_buckets - 1;
 	h->buckets = buckets;
 	h->hash_func = (params->hash_func == NULL) ?
-		DEFAULT_HASH_FUNC : params->hash_func;
+		default_hash_func : params->hash_func;
 	h->key_store = k;
 	h->free_slots = r;
 	h->hw_trans_mem_support = hw_trans_mem_support;
diff --git a/lib/librte_hash/rte_cuckoo_hash.h b/lib/librte_hash/rte_cuckoo_hash.h
index 658471a714..7a54e55575 100644
--- a/lib/librte_hash/rte_cuckoo_hash.h
+++ b/lib/librte_hash/rte_cuckoo_hash.h
@@ -28,14 +28,8 @@
 #define RETURN_IF_TRUE(cond, retval)
 #endif
 
-/* Hash function used if none is specified */
-#if defined(RTE_ARCH_X86) || defined(RTE_MACHINE_CPUFLAG_CRC32)
 #include <rte_hash_crc.h>
-#define DEFAULT_HASH_FUNC       rte_hash_crc
-#else
 #include <rte_jhash.h>
-#define DEFAULT_HASH_FUNC       rte_jhash
-#endif
 
 #if defined(RTE_ARCH_X86) || defined(RTE_ARCH_ARM64)
 /*