[dpdk-stable] patch 'hash: fix ring size' has been queued to stable release 16.07.1

[dpdk-stable] patch 'hash: fix ring size' has been queued to stable release 16.07.1

[Yuanhan Liu]

Hi,

FYI, your patch has been queued to stable release 16.07.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable
yet. It will be pushed if I get no objections before this Friday.
So please shutout if anyone has objections.

Thanks.

	--yliu

---
>From ee457d2e0b289d1798e2210263458b34f938b500 Mon Sep 17 00:00:00 2001
From: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Date: Fri, 26 Aug 2016 22:30:07 +0100
Subject: [PATCH] hash: fix ring size

[ upstream commit 1621f69abb6cc9db3047ee77835a44f68678d4a2 ]

Ring stores the free slots available to be used in the key table.
The ring size was being increased by 1, because of the dummy slot,
used for key misses, but this is not actually stored in the ring,
so there is no need to increase it.

Fixes: 5915699153d7 ("hash: fix scaling by reducing contention")

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Saikrishna Edupuganti <saikrishna.edupuganti@intel.com>
---
 lib/librte_hash/rte_cuckoo_hash.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
index 26e54f6..63fa036 100644
--- a/lib/librte_hash/rte_cuckoo_hash.c
+++ b/lib/librte_hash/rte_cuckoo_hash.c
@@ -159,7 +159,8 @@ rte_hash_create(const struct rte_hash_parameters *params)
 		num_key_slots = params->entries + 1;
 
 	snprintf(ring_name, sizeof(ring_name), "HT_%s", params->name);
-	r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots),
+	/* Create ring (Dummy slot index is not enqueued) */
+	r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots - 1),
 			params->socket_id, 0);
 	if (r == NULL) {
 		RTE_LOG(ERR, HASH, "memory allocation failed\n");
-- 
1.9.0