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{
    "id": 54419,
    "url": "http://patches.dpdk.org/api/covers/54419/?format=api",
    "web_url": "http://patches.dpdk.org/cover/54419/",
    "project": {
        "id": 1,
        "url": "http://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"
    },
    "msgid": "<1559750328-22377-1-git-send-email-phil.yang@arm.com>",
    "date": "2019-06-05T15:58:45",
    "name": "[v1,0/3] MCS queued lock implementation",
    "submitter": {
        "id": 833,
        "url": "http://patches.dpdk.org/api/people/833/?format=api",
        "name": "Phil Yang",
        "email": "phil.yang@arm.com"
    },
    "mbox": "http://patches.dpdk.org/cover/54419/mbox/",
    "series": [
        {
            "id": 4910,
            "url": "http://patches.dpdk.org/api/series/4910/?format=api",
            "web_url": "http://patches.dpdk.org/project/dpdk/list/?series=4910",
            "date": "2019-06-05T15:58:45",
            "name": "MCS queued lock implementation",
            "version": 1,
            "mbox": "http://patches.dpdk.org/series/4910/mbox/"
        }
    ],
    "comments": "http://patches.dpdk.org/api/covers/54419/comments/",
    "headers": {
        "X-Mailer": "git-send-email 2.7.4",
        "List-Id": "DPDK patches and discussions <dev.dpdk.org>",
        "From": "Phil Yang <phil.yang@arm.com>",
        "List-Help": "<mailto:dev-request@dpdk.org?subject=help>",
        "Date": "Wed,  5 Jun 2019 23:58:45 +0800",
        "X-BeenThere": "dev@dpdk.org",
        "X-Mailman-Version": "2.1.15",
        "Delivered-To": "patchwork@dpdk.org",
        "Cc": "thomas@monjalon.net, jerinj@marvell.com, hemant.agrawal@nxp.com,\n\tHonnappa.Nagarahalli@arm.com, gavin.hu@arm.com, phil.yang@arm.com,\n\tnd@arm.com",
        "To": "dev@dpdk.org",
        "Errors-To": "dev-bounces@dpdk.org",
        "Sender": "\"dev\" <dev-bounces@dpdk.org>",
        "Return-Path": "<dev-bounces@dpdk.org>",
        "List-Subscribe": "<https://mails.dpdk.org/listinfo/dev>,\n\t<mailto:dev-request@dpdk.org?subject=subscribe>",
        "List-Post": "<mailto:dev@dpdk.org>",
        "Received": [
            "from [92.243.14.124] (localhost [127.0.0.1])\n\tby dpdk.org (Postfix) with ESMTP id A8D7C1BBB4;\n\tWed,  5 Jun 2019 17:59:41 +0200 (CEST)",
            "from foss.arm.com (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70])\n\tby dpdk.org (Postfix) with ESMTP id 7D44B1BBA1\n\tfor <dev@dpdk.org>; Wed,  5 Jun 2019 17:59:40 +0200 (CEST)",
            "from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249])\n\tby usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 90373374;\n\tWed,  5 Jun 2019 08:59:39 -0700 (PDT)",
            "from phil-VirtualBox.shanghai.arm.com (unknown [10.171.20.59])\n\tby usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id\n\t124083F246; Wed,  5 Jun 2019 08:59:37 -0700 (PDT)"
        ],
        "List-Archive": "<http://mails.dpdk.org/archives/dev/>",
        "Subject": "[dpdk-dev] [PATCH v1 0/3] MCS queued lock implementation",
        "Message-Id": "<1559750328-22377-1-git-send-email-phil.yang@arm.com>",
        "Precedence": "list",
        "List-Unsubscribe": "<https://mails.dpdk.org/options/dev>,\n\t<mailto:dev-request@dpdk.org?subject=unsubscribe>",
        "X-Original-To": "patchwork@dpdk.org"
    },
    "content": "This patch set added MCS lock library and its unit test.\n\nThe MCS lock (proposed by JOHN M. MELLOR-CRUMMEY and MICHAEL L. SCOTT) provides\nscalability by spinning on a CPU/thread local variable which avoids expensive\ncache bouncings. It provides fairness by maintaining a list of acquirers and\npassing the lock to each CPU/thread in the order they acquired the lock.\n\nReferences:\n1. http://web.mit.edu/6.173/www/currentsemester/readings/R06-scalable-synchronization-1991.pdf\n2. https://lwn.net/Articles/590243/\n\nMirco-benchmarking result:\n------------------------------------------------------------------------------------------------\nMCS lock                      | spinlock                       | ticket lock\n------------------------------+--------------------------------+--------------------------------\nTest with lock on 13 cores... |  Test with lock on 14 cores... |  Test with lock on 14 cores...\nCore [15] Cost Time = 22426 us|  Core [14] Cost Time = 47974 us|  Core [14] cost time = 66761 us\nCore [16] Cost Time = 22382 us|  Core [15] Cost Time = 46979 us|  Core [15] cost time = 66766 us\nCore [17] Cost Time = 22294 us|  Core [16] Cost Time = 46044 us|  Core [16] cost time = 66761 us\nCore [18] Cost Time = 22412 us|  Core [17] Cost Time = 28793 us|  Core [17] cost time = 66767 us\nCore [19] Cost Time = 22407 us|  Core [18] Cost Time = 48349 us|  Core [18] cost time = 66758 us\nCore [20] Cost Time = 22436 us|  Core [19] Cost Time = 19381 us|  Core [19] cost time = 66766 us\nCore [21] Cost Time = 22414 us|  Core [20] Cost Time = 47914 us|  Core [20] cost time = 66763 us\nCore [22] Cost Time = 22405 us|  Core [21] Cost Time = 48333 us|  Core [21] cost time = 66766 us\nCore [23] Cost Time = 22435 us|  Core [22] Cost Time = 38900 us|  Core [22] cost time = 66749 us\nCore [24] Cost Time = 22401 us|  Core [23] Cost Time = 45374 us|  Core [23] cost time = 66765 us\nCore [25] Cost Time = 22408 us|  Core [24] Cost Time = 16121 us|  Core [24] cost time = 66762 us\nCore [26] Cost Time = 22380 us|  Core [25] Cost Time = 42731 us|  Core [25] cost time = 66768 us\nCore [27] Cost Time = 22395 us|  Core [26] Cost Time = 29439 us|  Core [26] cost time = 66768 us\n                              |  Core [27] Cost Time = 38071 us|  Core [27] cost time = 66767 us\n------------------------------+--------------------------------+--------------------------------\nTotal Cost Time = 291195 us   |  Total Cost Time = 544403 us   |  Total cost time = 934687 us\n------------------------------------------------------------------------------------------------\n\n\nPhil Yang (3):\n  eal/mcslock: add mcs queued lock implementation\n  eal/mcslock: use generic msc queued lock on all arch\n  test/mcslock: add mcs queued lock unit test\n\n MAINTAINERS                                        |   5 +\n app/test/Makefile                                  |   1 +\n app/test/autotest_data.py                          |   6 +\n app/test/autotest_test_funcs.py                    |  32 +++\n app/test/meson.build                               |   2 +\n app/test/test_mcslock.c                            | 248 +++++++++++++++++++++\n doc/api/doxy-api-index.md                          |   1 +\n doc/guides/rel_notes/release_19_08.rst             |   6 +\n lib/librte_eal/common/Makefile                     |   2 +-\n .../common/include/arch/arm/rte_mcslock.h          |  23 ++\n .../common/include/arch/ppc_64/rte_mcslock.h       |  19 ++\n .../common/include/arch/x86/rte_mcslock.h          |  19 ++\n .../common/include/generic/rte_mcslock.h           | 169 ++++++++++++++\n lib/librte_eal/common/meson.build                  |   1 +\n 14 files changed, 533 insertions(+), 1 deletion(-)\n create mode 100644 app/test/test_mcslock.c\n create mode 100644 lib/librte_eal/common/include/arch/arm/rte_mcslock.h\n create mode 100644 lib/librte_eal/common/include/arch/ppc_64/rte_mcslock.h\n create mode 100644 lib/librte_eal/common/include/arch/x86/rte_mcslock.h\n create mode 100644 lib/librte_eal/common/include/generic/rte_mcslock.h"
}