From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerin Jacob Subject: [PATCH] ethdev: fix a regression due to cache alignment issue Date: Sat, 10 Feb 2018 15:12:20 +0530 Message-ID: <20180210094220.16201-1-jerin.jacob@caviumnetworks.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Jerin Jacob , Matan Azrad , Thomas Monjalon , Konstantin Ananyev , Pavan Nikhilesh To: dev@dpdk.org Return-path: Received: from NAM03-DM3-obe.outbound.protection.outlook.com (mail-dm3nam03on0089.outbound.protection.outlook.com [104.47.41.89]) by dpdk.org (Postfix) with ESMTP id 8620A1B62B for ; Sat, 10 Feb 2018 10:43:12 +0100 (CET) List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Prior to "ethdev: add port ownership" change, the fast path structure struct rte_eth_dev->data was cache aligned due to the fact that eth_dev_data was allocated from rte_malloc with cache aligned attribute. "ethdev: add port ownership" change set introduced a rte_eth_dev_shared_data container for port ownership change, This resulted in rte_eth_dev->data memory as cache unaligned. Added a compiler alignment attribute to make sure rte_eth_dev->data always cache aligned and hence compiler can load/store the elements in struct rte_eth_dev_data as naturally aligned. Some platform like thunderx + l3fwd showed 1% regression in the performance with the offending changeset. Fixes: 5b7ba31148a8 ("ethdev: add port ownership") Cc: Matan Azrad Cc: Thomas Monjalon Cc: Konstantin Ananyev Signed-off-by: Jerin Jacob Signed-off-by: Pavan Nikhilesh --- lib/librte_ether/rte_ethdev_core.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/librte_ether/rte_ethdev_core.h b/lib/librte_ether/rte_ethdev_core.h index 315b31723..e5681e466 100644 --- a/lib/librte_ether/rte_ethdev_core.h +++ b/lib/librte_ether/rte_ethdev_core.h @@ -601,7 +601,7 @@ struct rte_eth_dev_data { struct rte_vlan_filter_conf vlan_filter_conf; /**< VLAN filter configuration. */ struct rte_eth_dev_owner owner; /**< The port owner. */ -}; +} __rte_cache_aligned; /** * @internal -- 2.16.1