From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 8799FB39C for ; Wed, 3 Sep 2014 17:45:43 +0200 (CEST) Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga102.fm.intel.com with ESMTP; 03 Sep 2014 08:49:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,458,1406617200"; d="scan'208";a="585697549" Received: from irvmail001.ir.intel.com ([163.33.26.43]) by fmsmga001.fm.intel.com with ESMTP; 03 Sep 2014 08:49:40 -0700 Received: from sivswdev02.ir.intel.com (sivswdev02.ir.intel.com [10.237.217.46]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id s83Fndfq025417; Wed, 3 Sep 2014 16:49:39 +0100 Received: from sivswdev02.ir.intel.com (localhost [127.0.0.1]) by sivswdev02.ir.intel.com with ESMTP id s83FndKF010426; Wed, 3 Sep 2014 16:49:39 +0100 Received: (from bricha3@localhost) by sivswdev02.ir.intel.com with id s83FndLX010421; Wed, 3 Sep 2014 16:49:39 +0100 From: Bruce Richardson To: dev@dpdk.org Date: Wed, 3 Sep 2014 16:49:27 +0100 Message-Id: <1409759378-10113-3-git-send-email-bruce.richardson@intel.com> X-Mailer: git-send-email 1.7.0.7 In-Reply-To: <1409759378-10113-1-git-send-email-bruce.richardson@intel.com> References: <1409759378-10113-1-git-send-email-bruce.richardson@intel.com> Subject: [dpdk-dev] [PATCH 02/13] mbuf: reorder fields by time of use X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 Sep 2014 15:45:44 -0000 * Reorder the fields in the mbuf so that we have fields that are used$ together side-by-side in the structure. This means that we have a$ contiguous block of 8-bytes in the mbuf which are used to reset an mbuf$ of descriptor rearm, and a block of 16-bytes of data (excluding flags) which are set on RX from the received packet descriptor. * Use dummy fields as appropraite to ensure alignment or to reserve gaps for later field additions. * Place most items which are not used by fast-path RX separately at the end of the structure so they can later be moved to a separate cache line. [The l2/l3 length fields are not moved at this stage as doing so will cause overflow to the next cache line]. Signed-off-by: Bruce Richardson --- lib/librte_mbuf/rte_mbuf.h | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h index 669e7f5..f136d37 100644 --- a/lib/librte_mbuf/rte_mbuf.h +++ b/lib/librte_mbuf/rte_mbuf.h @@ -115,16 +115,12 @@ extern "C" { * The generic rte_mbuf, containing a packet mbuf. */ struct rte_mbuf { - struct rte_mempool *pool; /**< Pool from which mbuf was allocated. */ void *buf_addr; /**< Virtual address of segment buffer. */ phys_addr_t buf_physaddr; /**< Physical address of segment buffer. */ - uint16_t buf_len; /**< Length of segment buffer. */ - /* valid for any segment */ - struct rte_mbuf *next; /**< Next segment of scattered packet. */ + /* next 8 bytes are initialised on RX descriptor rearm */ + uint16_t buf_len; /**< Length of segment buffer. */ uint16_t data_off; - uint16_t data_len; /**< Amount of data in segment buffer. */ - uint32_t pkt_len; /**< Total pkt len: sum of all segments. */ #ifdef RTE_MBUF_REFCNT /** @@ -142,14 +138,17 @@ struct rte_mbuf { #else uint16_t refcnt_reserved; /**< Do not use this field */ #endif - uint16_t reserved; /**< Unused field. Required for padding */ - uint16_t ol_flags; /**< Offload features. */ - - /* these fields are valid for first segment only */ uint8_t nb_segs; /**< Number of segments. */ uint8_t port; /**< Input port. */ - /* offload features, valid for first segment only */ + uint16_t ol_flags; /**< Offload features. */ + uint16_t reserved0; /**< Unused field. Required for padding */ + uint32_t reserved1; /**< Unused field. Required for padding */ + + /* remaining bytes are set on RX when pulling packet from descriptor */ + uint16_t reserved2; /**< Unused field. Required for padding */ + uint16_t data_len; /**< Amount of data in segment buffer. */ + uint32_t pkt_len; /**< Total pkt len: sum of all segments. */ uint16_t l3_len:9; /**< L3 (IP) Header Length. */ uint16_t l2_len:7; /**< L2 (MAC) Header Length. */ uint16_t vlan_tci; /**< VLAN Tag Control Identifier (CPU order). */ @@ -162,6 +161,10 @@ struct rte_mbuf { uint32_t sched; /**< Hierarchical scheduler */ } hash; /**< hash information */ + /* fields only used in slow path or on TX */ + struct rte_mempool *pool; /**< Pool from which mbuf was allocated. */ + struct rte_mbuf *next; /**< Next segment of scattered packet. */ + union { uint8_t metadata[0]; uint16_t metadata16[0]; -- 1.9.3