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{
    "id": 81856,
    "url": "https://patches.dpdk.org/api/covers/81856/?format=api",
    "web_url": "https://patches.dpdk.org/project/dpdk/cover/20201023044343.13462-1-honnappa.nagarahalli@arm.com/",
    "project": {
        "id": 1,
        "url": "https://patches.dpdk.org/api/projects/1/?format=api",
        "name": "DPDK",
        "link_name": "dpdk",
        "list_id": "dev.dpdk.org",
        "list_email": "dev@dpdk.org",
        "web_url": "http://core.dpdk.org",
        "scm_url": "git://dpdk.org/dpdk",
        "webscm_url": "http://git.dpdk.org/dpdk",
        "list_archive_url": "https://inbox.dpdk.org/dev",
        "list_archive_url_format": "https://inbox.dpdk.org/dev/{}",
        "commit_url_format": ""
    },
    "msgid": "<20201023044343.13462-1-honnappa.nagarahalli@arm.com>",
    "list_archive_url": "https://inbox.dpdk.org/dev/20201023044343.13462-1-honnappa.nagarahalli@arm.com",
    "date": "2020-10-23T04:43:38",
    "name": "[v3,0/5] lib/ring: add zero copy APIs",
    "submitter": {
        "id": 1045,
        "url": "https://patches.dpdk.org/api/people/1045/?format=api",
        "name": "Honnappa Nagarahalli",
        "email": "honnappa.nagarahalli@arm.com"
    },
    "mbox": "https://patches.dpdk.org/project/dpdk/cover/20201023044343.13462-1-honnappa.nagarahalli@arm.com/mbox/",
    "series": [
        {
            "id": 13245,
            "url": "https://patches.dpdk.org/api/series/13245/?format=api",
            "web_url": "https://patches.dpdk.org/project/dpdk/list/?series=13245",
            "date": "2020-10-23T04:43:38",
            "name": "lib/ring: add zero copy APIs",
            "version": 3,
            "mbox": "https://patches.dpdk.org/series/13245/mbox/"
        }
    ],
    "comments": "https://patches.dpdk.org/api/covers/81856/comments/",
    "headers": {
        "Return-Path": "<dev-bounces@dpdk.org>",
        "X-Original-To": "patchwork@inbox.dpdk.org",
        "Delivered-To": "patchwork@inbox.dpdk.org",
        "Received": [
            "from dpdk.org (dpdk.org [92.243.14.124])\n\tby inbox.dpdk.org (Postfix) with ESMTP id 42390A04DE;\n\tFri, 23 Oct 2020 06:44:05 +0200 (CEST)",
            "from [92.243.14.124] (localhost [127.0.0.1])\n\tby dpdk.org (Postfix) with ESMTP id DA2066966;\n\tFri, 23 Oct 2020 06:44:03 +0200 (CEST)",
            "from foss.arm.com (foss.arm.com [217.140.110.172])\n by dpdk.org (Postfix) with ESMTP id 1D40F677C\n for <dev@dpdk.org>; Fri, 23 Oct 2020 06:44:02 +0200 (CEST)",
            "from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14])\n by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8B800101E;\n Thu, 22 Oct 2020 21:44:00 -0700 (PDT)",
            "from qc2400f-1.austin.arm.com (qc2400f-1.austin.arm.com\n [10.118.12.27])\n by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7EFBB3F66B;\n Thu, 22 Oct 2020 21:44:00 -0700 (PDT)"
        ],
        "From": "Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>",
        "To": "dev@dpdk.org, honnappa.nagarahalli@arm.com, konstantin.ananyev@intel.com",
        "Cc": "olivier.matz@6wind.com, david.marchand@redhat.com,\n dharmik.thakkar@arm.com,\n ruifeng.wang@arm.com, nd@arm.com",
        "Date": "Thu, 22 Oct 2020 23:43:38 -0500",
        "Message-Id": "<20201023044343.13462-1-honnappa.nagarahalli@arm.com>",
        "X-Mailer": "git-send-email 2.17.1",
        "In-Reply-To": "<20200224203931.21256-1-honnappa.nagarahalli@arm.com>",
        "References": "<20200224203931.21256-1-honnappa.nagarahalli@arm.com>",
        "Subject": "[dpdk-dev] [PATCH v3 0/5] lib/ring: add zero copy APIs",
        "X-BeenThere": "dev@dpdk.org",
        "X-Mailman-Version": "2.1.15",
        "Precedence": "list",
        "List-Id": "DPDK patches and discussions <dev.dpdk.org>",
        "List-Unsubscribe": "<https://mails.dpdk.org/options/dev>,\n <mailto:dev-request@dpdk.org?subject=unsubscribe>",
        "List-Archive": "<http://mails.dpdk.org/archives/dev/>",
        "List-Post": "<mailto:dev@dpdk.org>",
        "List-Help": "<mailto:dev-request@dpdk.org?subject=help>",
        "List-Subscribe": "<https://mails.dpdk.org/listinfo/dev>,\n <mailto:dev-request@dpdk.org?subject=subscribe>",
        "Errors-To": "dev-bounces@dpdk.org",
        "Sender": "\"dev\" <dev-bounces@dpdk.org>"
    },
    "content": "It is pretty common for the DPDK applications to be deployed in\nsemi-pipeline model. In these models, a small number of cores\n(typically 1) are designated as I/O cores. The I/O cores work\non receiving and transmitting packets from the NIC and several\npacket processing cores. The IO core and the packet processing\ncores exchange the packets over a ring. Typically, such applications\nreceive the mbufs in a temporary array and copy the mbufs on\nto the ring. Depending on the requirements the packets\ncould be copied in batches of 32, 64 etc resulting in 256B,\n512B etc memory copy.\n\nThe zero copy APIs help avoid intermediate copies by exposing\nthe space on the ring directly to the application.\n\nv3:\n1) Changed the name of the APIs to 'zero-copy (zc)'\n2) Made the address calculation simpler\n3) Structure to return the data to the user is aligned on\n   cache line boundary.\n4) Added functional and stress test cases\n\nv2: changed the patch to use the SP-SC and HTS modes\n\nv1: Initial version\n\nHonnappa Nagarahalli (5):\n  test/ring: fix the memory dump size\n  lib/ring: add zero copy APIs\n  test/ring: move common function to header file\n  test/ring: add functional tests for zero copy APIs\n  test/ring: add stress tests for zero copy APIs\n\n app/test/meson.build                   |   2 +\n app/test/test_ring.c                   | 207 +++++++++-\n app/test/test_ring.h                   |  53 +++\n app/test/test_ring_mt_peek_stress_zc.c |  56 +++\n app/test/test_ring_st_peek_stress_zc.c |  65 +++\n app/test/test_ring_stress.c            |   6 +\n app/test/test_ring_stress.h            |   2 +\n app/test/test_ring_stress_impl.h       |   2 +-\n lib/librte_ring/meson.build            |   1 +\n lib/librte_ring/rte_ring_elem.h        |   1 +\n lib/librte_ring/rte_ring_peek_zc.h     | 542 +++++++++++++++++++++++++\n 11 files changed, 925 insertions(+), 12 deletions(-)\n create mode 100644 app/test/test_ring_mt_peek_stress_zc.c\n create mode 100644 app/test/test_ring_st_peek_stress_zc.c\n create mode 100644 lib/librte_ring/rte_ring_peek_zc.h"
}