From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <konstantin.ananyev@intel.com> Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id 1C4F21B6DB for <dev@dpdk.org>; Mon, 26 Nov 2018 10:34:02 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Nov 2018 01:34:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,281,1539673200"; d="scan'208";a="111527722" Received: from irsmsx105.ger.corp.intel.com ([163.33.3.28]) by orsmga002.jf.intel.com with ESMTP; 26 Nov 2018 01:34:00 -0800 Received: from irsmsx106.ger.corp.intel.com ([169.254.8.8]) by irsmsx105.ger.corp.intel.com ([169.254.7.144]) with mapi id 14.03.0415.000; Mon, 26 Nov 2018 09:33:59 +0000 From: "Ananyev, Konstantin" <konstantin.ananyev@intel.com> To: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>, "Varghese, Vipin" <vipin.varghese@intel.com>, Stephen Hemminger <stephen@networkplumber.org> CC: "Pattan, Reshma" <reshma.pattan@intel.com>, "dev@dpdk.org" <dev@dpdk.org>, "thomas@monjalon.net" <thomas@monjalon.net>, "Mcnamara, John" <john.mcnamara@intel.com>, "Byrne, Stephen1" <stephen1.byrne@intel.com>, "Glynn, Michael J" <michael.j.glynn@intel.com>, "Patel, Amol" <amol.patel@intel.com> Thread-Topic: [PATCH v4 5/9] app/procinfo: add support for show tm Thread-Index: AQHUhT7DxSutPQTiRki7qeUOKBTbk6VhycOwgAABymA= Date: Mon, 26 Nov 2018 09:33:59 +0000 Message-ID: <2601191342CEEE43887BDE71AB977258010CEBC50B@IRSMSX106.ger.corp.intel.com> References: <20181106124912.40700-1-vipin.varghese@intel.com> <20181106124912.40700-5-vipin.varghese@intel.com> <3AEA2BF9852C6F48A459DA490692831F2A3D58A3@irsmsx110.ger.corp.intel.com> <4C9E0AB70F954A408CC4ADDBF0F8FA7D4D2C1435@BGSMSX101.gar.corp.intel.com> <3AEA2BF9852C6F48A459DA490692831F2A3D61A6@irsmsx110.ger.corp.intel.com> <4C9E0AB70F954A408CC4ADDBF0F8FA7D4D2C1A45@BGSMSX101.gar.corp.intel.com> <3AEA2BF9852C6F48A459DA490692831F2A3D6264@irsmsx110.ger.corp.intel.com> <4C9E0AB70F954A408CC4ADDBF0F8FA7D4D2C1A79@BGSMSX101.gar.corp.intel.com> <3AEA2BF9852C6F48A459DA490692831F2A3D62FB@irsmsx110.ger.corp.intel.com> <4C9E0AB70F954A408CC4ADDBF0F8FA7D4D2C1B26@BGSMSX101.gar.corp.intel.com> <20181123092215.50d299ae@xeon-e3> <4C9E0AB70F954A408CC4ADDBF0F8FA7D4D2C1FD9@BGSMSX101.gar.corp.intel.com> <2601191342CEEE43887BDE71AB977258010CEBC4DC@IRSMSX106.ger.corp.intel.com> In-Reply-To: <2601191342CEEE43887BDE71AB977258010CEBC4DC@IRSMSX106.ger.corp.intel.com> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiZjM4MzQyYTctNmQyNy00YmE1LTk0YzYtMTRiYzU3N2IxYzVlIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoiVm1CTHRsa21IOG9hUE4xMldpR09mMzJrWENPeVRoa3ZNaGY1UlZ6dmVrMHFGcmdBVXh6QUQyc1I3TlR4Z3lvKyJ9 x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.0.400.15 dlp-reaction: no-action x-originating-ip: [163.33.239.180] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v4 5/9] app/procinfo: add support for show tm 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>, <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>, <mailto:dev-request@dpdk.org?subject=subscribe> X-List-Received-Date: Mon, 26 Nov 2018 09:34:03 -0000 > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Ananyev, Konstantin > Sent: Monday, November 26, 2018 9:28 AM > To: Varghese, Vipin <vipin.varghese@intel.com>; Stephen Hemminger <stephe= n@networkplumber.org> > Cc: Pattan, Reshma <reshma.pattan@intel.com>; dev@dpdk.org; thomas@monjal= on.net; Mcnamara, John <john.mcnamara@intel.com>; > Byrne, Stephen1 <stephen1.byrne@intel.com>; Glynn, Michael J <michael.j.g= lynn@intel.com>; Patel, Amol <amol.patel@intel.com> > Subject: Re: [dpdk-dev] [PATCH v4 5/9] app/procinfo: add support for show= tm >=20 >=20 >=20 > > -----Original Message----- > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Varghese, Vipin > > Sent: Monday, November 26, 2018 4:15 AM > > To: Stephen Hemminger <stephen@networkplumber.org> > > Cc: Pattan, Reshma <reshma.pattan@intel.com>; dev@dpdk.org; thomas@monj= alon.net; Mcnamara, John > <john.mcnamara@intel.com>; > > Byrne, Stephen1 <stephen1.byrne@intel.com>; Glynn, Michael J <michael.j= .glynn@intel.com>; Patel, Amol <amol.patel@intel.com> > > Subject: Re: [dpdk-dev] [PATCH v4 5/9] app/procinfo: add support for sh= ow tm > > > > Hi Stephen, > > > > snipped > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > + if ((ret) | (!is_leaf)) > > > > > > > > > > > > + > > > > > > > > > > > > > > > > > > > > > > Is the operator here should be || ? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Check is done for 'if either ret is not 0 or if it ret = is > > > > > > > > > > 0 but not leaf' we skip leaf details print. If 'ret is = 0 and is leaf' > > > > > > > > > > we skip continue to print > > > > > > > > > leaf details. > > > > > > > > > > > > > > > > > > IMO, using logical operator over bitwise operator is good > > > > > > > > > here in if statement > > > > > > > > . > > > > > > > > > Like below.? > > > > > > > > > > > > > > > > > > If (ret || (is_leaf =3D=3D 0 )) > > > > > > > > > > > > > > > > Thanks for the information, if the logic is correct do I ne= ed > > > > > > > > to change for v6 > > > > > > > > > > > > > > > > > > > > > > OK in v6, but you can wait to hear more comments from others = if > > > > > > > any before sending v6 . > > > > > > > > > > > > Ok thanks Reshma, but can you tell me how the earlier logic fai= ls > > > > > > and runs slow compared to logical or? > > > > > > > > > > Not about faster or slower. > > > > > > > > Now I see, I was wondering the suggestion was for improvement for > > > performance. > > > > > > > > > > > > > > Logical operators are commonly used in decision making in C progr= amming. > > > > > Bitwise operators are used in C programming to perform bit-level = operations. > > > > > > > > > > > > > Agreed > > > > > > > > > Since , above if condition is for decision making here logical || > > > > > operator will fit , so I am suggesting to use that. > > > > > > > > > > > > > But bitwise OR is not wrong right? > > > > > > > > > We don't need to do any bitwise manipulation in if condition to > > > > > make the decision, so bitwise | operator is not needed > > > > > > > > We can correct this in next patch set not v6 if this is only change= for 'show tm' > > > > > > It could be that compiler might optimize logical into bitwise operati= on to avoid > > > cost of conditional branch (if there are no side effects). > > > > > > Checking with 'EXTRA_CFLAGS=3D-g' we get the code generated as > > > > """ > > if ((ret) | (!is_leaf)) > > 9a512: 8b 85 28 fd ff ff mov eax,DWORD PTR [rbp-0x2d8= ] > > 9a518: 85 c0 test eax,eax > > 9a51a: 0f 94 c0 sete al > > 9a51d: 0f b6 c0 movzx eax,al > > 9a520: 0b 85 3c fd ff ff or eax,DWORD PTR [rbp-0x2c4= ] > > 9a526: 85 c0 test eax,eax > > 9a528: 75 74 jne 9a59e <show_tm+0x73e> > > continue; > > """ > > > > Looks like the is_leaf is picked assembly 'test' is done then byte is s= et to 1 based on flags. This is then or with 'ret'. I think your observatio= n > is > > correct 'compiler is remapping to or' >=20 > If the operator is '|' what else except of 'OR' you expect it to be remap= ped? BTW, I am agree with Reshma it has to be '||' here.