From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by dpdk.org (Postfix) with ESMTP id 22C8C2C24 for ; Fri, 15 Mar 2019 12:41:20 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Mar 2019 04:41:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,482,1544515200"; d="scan'208";a="125721297" Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by orsmga008.jf.intel.com with ESMTP; 15 Mar 2019 04:41:17 -0700 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.210]) by IRSMSX152.ger.corp.intel.com ([169.254.6.139]) with mapi id 14.03.0415.000; Fri, 15 Mar 2019 11:41:16 +0000 From: "Ananyev, Konstantin" To: Joyce Kong , "dev@dpdk.org" CC: "nd@arm.com" , Gavin Hu , "jerinj@marvell.com" , "chaozhu@linux.vnet.ibm.com" , "Richardson, Bruce" , "thomas@monjalon.net" , "hemant.agrawal@nxp.com" , "honnappa.nagarahalli@arm.com" Thread-Topic: [PATCH v3 1/3] rwlock: reimplement with atomic builtins Thread-Index: AQHU2mgNs4dKxYvszEmkdD/Te6SCrqYMkpYg Date: Fri, 15 Mar 2019 11:41:16 +0000 Message-ID: <2601191342CEEE43887BDE71AB977258013655BF2A@irsmsx105.ger.corp.intel.com> References: <1544672265-219262-2-git-send-email-joyce.kong@arm.com> <1552569304-74817-2-git-send-email-joyce.kong@arm.com> In-Reply-To: <1552569304-74817-2-git-send-email-joyce.kong@arm.com> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNzdkMDYzNWUtN2M3NS00YThmLThjNjAtNjcxZWUxNDFjODhhIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoiTHpmSzEwSlBza3RZb0prcnlZZmtSajF1SU5VcmdkODNqdnJ5TmJxaEhWamFcL0pWckhKbEhsRitvSlRkYWtvdTIifQ== x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.0.400.15 dlp-reaction: no-action x-originating-ip: [163.33.239.182] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v3 1/3] rwlock: reimplement with atomic builtins X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Mar 2019 11:41:21 -0000 Hi, > The __sync builtin based implementation generates full memory > barriers ('dmb ish') on Arm platforms. Using C11 atomic builtins > to generate one way barriers. >=20 > Here is the assembly code of __sync_compare_and_swap builtin. > __sync_bool_compare_and_swap(dst, exp, src); > 0x000000000090f1b0 <+16>: e0 07 40 f9 ldr x0, [sp, #8] > 0x000000000090f1b4 <+20>: e1 0f 40 79 ldrh w1, [sp, #6] > 0x000000000090f1b8 <+24>: e2 0b 40 79 ldrh w2, [sp, #4] > 0x000000000090f1bc <+28>: 21 3c 00 12 and w1, w1, #0xffff > 0x000000000090f1c0 <+32>: 03 7c 5f 48 ldxrh w3, [x0] > 0x000000000090f1c4 <+36>: 7f 00 01 6b cmp w3, w1 > 0x000000000090f1c8 <+40>: 61 00 00 54 b.ne 0x90f1d4 > // b.any > 0x000000000090f1cc <+44>: 02 fc 04 48 stlxrh w4, w2, [x0] > 0x000000000090f1d0 <+48>: 84 ff ff 35 cbnz w4, 0x90f1c0 > > 0x000000000090f1d4 <+52>: bf 3b 03 d5 dmb ish > 0x000000000090f1d8 <+56>: e0 17 9f 1a cset w0, eq // eq =3D non= e >=20 > Signed-off-by: Gavin Hu > Tested-by: Joyce Kong > Acked-by: Jerin Jacob > --- Wouldn't it be plausible to change _try_ functions to use __atomic too (for= consistency)? Apart from that looks good to me. Konstantin From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by dpdk.space (Postfix) with ESMTP id 576C2A0096 for ; Fri, 15 Mar 2019 12:41:25 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id C98AC2C28; Fri, 15 Mar 2019 12:41:22 +0100 (CET) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by dpdk.org (Postfix) with ESMTP id 22C8C2C24 for ; Fri, 15 Mar 2019 12:41:20 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Mar 2019 04:41:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,482,1544515200"; d="scan'208";a="125721297" Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by orsmga008.jf.intel.com with ESMTP; 15 Mar 2019 04:41:17 -0700 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.210]) by IRSMSX152.ger.corp.intel.com ([169.254.6.139]) with mapi id 14.03.0415.000; Fri, 15 Mar 2019 11:41:16 +0000 From: "Ananyev, Konstantin" To: Joyce Kong , "dev@dpdk.org" CC: "nd@arm.com" , Gavin Hu , "jerinj@marvell.com" , "chaozhu@linux.vnet.ibm.com" , "Richardson, Bruce" , "thomas@monjalon.net" , "hemant.agrawal@nxp.com" , "honnappa.nagarahalli@arm.com" Thread-Topic: [PATCH v3 1/3] rwlock: reimplement with atomic builtins Thread-Index: AQHU2mgNs4dKxYvszEmkdD/Te6SCrqYMkpYg Date: Fri, 15 Mar 2019 11:41:16 +0000 Message-ID: <2601191342CEEE43887BDE71AB977258013655BF2A@irsmsx105.ger.corp.intel.com> References: <1544672265-219262-2-git-send-email-joyce.kong@arm.com> <1552569304-74817-2-git-send-email-joyce.kong@arm.com> In-Reply-To: <1552569304-74817-2-git-send-email-joyce.kong@arm.com> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNzdkMDYzNWUtN2M3NS00YThmLThjNjAtNjcxZWUxNDFjODhhIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoiTHpmSzEwSlBza3RZb0prcnlZZmtSajF1SU5VcmdkODNqdnJ5TmJxaEhWamFcL0pWckhKbEhsRitvSlRkYWtvdTIifQ== x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.0.400.15 dlp-reaction: no-action x-originating-ip: [163.33.239.182] Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v3 1/3] rwlock: reimplement with atomic builtins X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Message-ID: <20190315114116.Cy6kf6_UdpCKJ788quMxUghXPyx1u3CsMX6sN5fLz3U@z> Hi, > The __sync builtin based implementation generates full memory > barriers ('dmb ish') on Arm platforms. Using C11 atomic builtins > to generate one way barriers. >=20 > Here is the assembly code of __sync_compare_and_swap builtin. > __sync_bool_compare_and_swap(dst, exp, src); > 0x000000000090f1b0 <+16>: e0 07 40 f9 ldr x0, [sp, #8] > 0x000000000090f1b4 <+20>: e1 0f 40 79 ldrh w1, [sp, #6] > 0x000000000090f1b8 <+24>: e2 0b 40 79 ldrh w2, [sp, #4] > 0x000000000090f1bc <+28>: 21 3c 00 12 and w1, w1, #0xffff > 0x000000000090f1c0 <+32>: 03 7c 5f 48 ldxrh w3, [x0] > 0x000000000090f1c4 <+36>: 7f 00 01 6b cmp w3, w1 > 0x000000000090f1c8 <+40>: 61 00 00 54 b.ne 0x90f1d4 > // b.any > 0x000000000090f1cc <+44>: 02 fc 04 48 stlxrh w4, w2, [x0] > 0x000000000090f1d0 <+48>: 84 ff ff 35 cbnz w4, 0x90f1c0 > > 0x000000000090f1d4 <+52>: bf 3b 03 d5 dmb ish > 0x000000000090f1d8 <+56>: e0 17 9f 1a cset w0, eq // eq =3D non= e >=20 > Signed-off-by: Gavin Hu > Tested-by: Joyce Kong > Acked-by: Jerin Jacob > --- Wouldn't it be plausible to change _try_ functions to use __atomic too (for= consistency)? Apart from that looks good to me. Konstantin