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 392022716 for ; Fri, 23 Sep 2016 06:13:01 +0200 (CEST) Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga102.fm.intel.com with ESMTP; 22 Sep 2016 21:13:00 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.30,380,1470726000"; d="scan'208";a="12384569" Received: from yliu-dev.sh.intel.com ([10.239.67.162]) by fmsmga005.fm.intel.com with ESMTP; 22 Sep 2016 21:12:59 -0700 From: Yuanhan Liu To: dev@dpdk.org Cc: Maxime Coquelin , Yuanhan Liu Date: Fri, 23 Sep 2016 12:13:20 +0800 Message-Id: <1474604007-5221-1-git-send-email-yuanhan.liu@linux.intel.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1471939839-29778-1-git-send-email-yuanhan.liu@linux.intel.com> References: <1471939839-29778-1-git-send-email-yuanhan.liu@linux.intel.com> Subject: [dpdk-dev] [PATCH v2 0/7] vhost: add dequeue zero copy support 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: Fri, 23 Sep 2016 04:13:01 -0000 v2: - renamed "tx zero copy" to "dequeue zero copy", to reduce confusions. - hnadle the case that a desc buf might across 2 host phys pages - use MAP_POPULATE to let kernel populate the page tables - updated release note - doc-ed the limitations for the vm2nic case - merge 2 continuous guest phys memory region - and few more trivial changes, please see them in the corresponding patches This patch set enables vhost dequeue zero copy. The majority work goes to patch 4: "vhost: add dequeue zero copy". The basic idea of dequeue zero copy is, instead of copying data from the desc buf, here we let the mbuf reference the desc buf addr directly. The major issue behind that is how and when to update the used ring. You could check the commit log of patch 4 for more details. Patch 5 introduces a new flag, RTE_VHOST_USER_DEQUEUE_ZERO_COPY, to enable dequeue zero copy, which is disabled by default. The performance gain is quite impressive. For a simple dequeue workload (running rxonly in vhost-pmd and runnin txonly in guest testpmd), it yields 50+% performance boost for packet size 1500B. For VM2VM iperf test case, it's even better: about 70% boost. For small packets, the performance is worse (it's expected, as the extra overhead introduced by zero copy outweighs the benefits from saving few bytes copy). --- Yuanhan Liu (7): vhost: simplify memory regions handling vhost: get guest/host physical address mappings vhost: introduce last avail idx for dequeue vhost: add dequeue zero copy vhost: add a flag to enable dequeue zero copy examples/vhost: add an option to enable dequeue zero copy net/vhost: add an option to enable dequeue zero copy doc/guides/prog_guide/vhost_lib.rst | 35 +++- doc/guides/rel_notes/release_16_11.rst | 11 ++ drivers/net/vhost/rte_eth_vhost.c | 13 ++ examples/vhost/main.c | 19 +- lib/librte_vhost/rte_virtio_net.h | 1 + lib/librte_vhost/socket.c | 5 + lib/librte_vhost/vhost.c | 12 ++ lib/librte_vhost/vhost.h | 102 ++++++++--- lib/librte_vhost/vhost_user.c | 315 ++++++++++++++++++++++----------- lib/librte_vhost/virtio_net.c | 192 +++++++++++++++++--- 10 files changed, 543 insertions(+), 162 deletions(-) -- 1.9.0