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{ "id": 69843, "url": "https://patches.dpdk.org/api/covers/69843/?format=api", "web_url": "https://patches.dpdk.org/project/dpdk/cover/1588778884-13047-1-git-send-email-phil.yang@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": "<1588778884-13047-1-git-send-email-phil.yang@arm.com>", "list_archive_url": "https://inbox.dpdk.org/dev/1588778884-13047-1-git-send-email-phil.yang@arm.com", "date": "2020-05-06T15:27:58", "name": "[v6,0/6] use c11 atomics for service core lib", "submitter": { "id": 833, "url": "https://patches.dpdk.org/api/people/833/?format=api", "name": "Phil Yang", "email": "phil.yang@arm.com" }, "mbox": "https://patches.dpdk.org/project/dpdk/cover/1588778884-13047-1-git-send-email-phil.yang@arm.com/mbox/", "series": [ { "id": 9877, "url": "https://patches.dpdk.org/api/series/9877/?format=api", "web_url": "https://patches.dpdk.org/project/dpdk/list/?series=9877", "date": "2020-05-06T15:27:58", "name": "use c11 atomics for service core lib", "version": 6, "mbox": "https://patches.dpdk.org/series/9877/mbox/" } ], "comments": "https://patches.dpdk.org/api/covers/69843/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 4258FA034F;\n\tWed, 6 May 2020 17:28:49 +0200 (CEST)", "from [92.243.14.124] (localhost [127.0.0.1])\n\tby dpdk.org (Postfix) with ESMTP id C91B61D942;\n\tWed, 6 May 2020 17:28:48 +0200 (CEST)", "from foss.arm.com (foss.arm.com [217.140.110.172])\n by dpdk.org (Postfix) with ESMTP id C56331D939\n for <dev@dpdk.org>; Wed, 6 May 2020 17:28:47 +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 40208D6E;\n Wed, 6 May 2020 08:28:47 -0700 (PDT)", "from localhost.localdomain (unknown [172.31.20.19])\n by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 0151E3F68F;\n Wed, 6 May 2020 08:28:40 -0700 (PDT)" ], "From": "Phil Yang <phil.yang@arm.com>", "To": "dev@dpdk.org,\n\tharry.van.haaren@intel.com", "Cc": "thomas@monjalon.net, david.marchand@redhat.com,\n konstantin.ananyev@intel.com, jerinj@marvell.com, hemant.agrawal@nxp.com,\n gage.eads@intel.com, bruce.richardson@intel.com,\n Honnappa.Nagarahalli@arm.com, nd@arm.com", "Date": "Wed, 6 May 2020 23:27:58 +0800", "Message-Id": "<1588778884-13047-1-git-send-email-phil.yang@arm.com>", "X-Mailer": "git-send-email 2.7.4", "In-Reply-To": "<1588760683-11027-1-git-send-email-phil.yang@arm.com>", "References": "<1588760683-11027-1-git-send-email-phil.yang@arm.com>", "Subject": "[dpdk-dev] [PATCH v6 0/6] use c11 atomics for service core lib", "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": "The rte_atomic ops and rte_smp barriers enforce DMB barriers on aarch64.\nUsing c11 atomics with explicit memory ordering instead of the rte_atomic\nops and rte_smp barriers for inter-threads synchronization can uplift the\nperformance on aarch64 and no performance loss on x86.\n\nThis patchset contains:\n1) fix race condition for MT unsafe service.\n2) clean up redundant code.\n3) use c11 atomics for service core lib to avoid unnecessary barriers.\n\nv2:\nStill waiting on Harry for the final solution on the MT unsafe race\ncondition issue. But I have incorporated the comments so far.\n1. add 'Fixes' tag for bug-fix patches.\n2. remove 'Fixes' tag for code cleanup patches.\n3. remove unused parameter for service_dump_one function.\n4. replace the execute_lock atomic CAS operation to spinlock_try_lock.\n5. use c11 atomics with RELAXED memory ordering for num_mapped_cores.\n6. relax barriers for guard variables runstate, comp_runstate and\n app_runstate with c11 one-way barriers.\n\nv3:\nSending this version since Phil is on holiday.\n1. Updated the API documentation to indicate how the locking\n can be avoided.\n\nv4:\n1. Fix the nits in 2/6 commit message and comments in code.\n\nv5:\n1. Remove redundant libatomic clang dependency claim code as it has been\nadded in global. (The commit da4eae278b56)\n\nv6:\n1. Fix coding style issue. Remove illegal Change-ID tag in patch 5/6.\n\nHonnappa Nagarahalli (2):\n service: fix race condition for MT unsafe service\n service: fix identification of service running on other lcore\n\nPhil Yang (4):\n service: remove rte prefix from static functions\n service: remove redundant code\n service: optimize with c11 atomics\n service: relax barriers with C11 atomics\n\n lib/librte_eal/common/rte_service.c | 234 +++++++++++++------------\n lib/librte_eal/include/rte_service.h | 8 +-\n lib/librte_eal/include/rte_service_component.h | 6 +-\n 3 files changed, 137 insertions(+), 111 deletions(-)" }