From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 905D21B1CE for ; Mon, 15 Apr 2019 14:24:52 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Apr 2019 05:24:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,353,1549958400"; d="scan'208";a="149546344" Received: from irsmsx103.ger.corp.intel.com ([163.33.3.157]) by FMSMGA003.fm.intel.com with ESMTP; 15 Apr 2019 05:24:50 -0700 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.31]) by IRSMSX103.ger.corp.intel.com ([169.254.3.30]) with mapi id 14.03.0415.000; Mon, 15 Apr 2019 13:24:47 +0100 From: "Ananyev, Konstantin" To: Stephen Hemminger , Honnappa Nagarahalli CC: "paulmck@linux.ibm.com" , "Kovacevic, Marko" , "dev@dpdk.org" , "Gavin Hu (Arm Technology China)" , Dharmik Thakkar , Malvika Gupta , nd Thread-Topic: [PATCH v5 1/3] rcu: add RCU library supporting QSBR mechanism Thread-Index: AQHU8W09YQlYNBQMIUeythDpmiY2L6Y5BHAAgAAFAYCAAAupgIAEE9Rg Date: Mon, 15 Apr 2019 12:24:47 +0000 Message-ID: <2601191342CEEE43887BDE71AB9772580148A97E53@irsmsx105.ger.corp.intel.com> References: <20181122033055.3431-1-honnappa.nagarahalli@arm.com> <20190412202039.46902-1-honnappa.nagarahalli@arm.com> <20190412202039.46902-2-honnappa.nagarahalli@arm.com> <20190412150650.3709358e@shemminger-XPS-13-9360> <20190412160629.670eacd1@shemminger-XPS-13-9360> In-Reply-To: <20190412160629.670eacd1@shemminger-XPS-13-9360> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNzUxNjcyNDYtYTVlZS00M2Q4LWE1NjQtZmQ2NGJjZDBkMDU3IiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoiUlRxVWtDTGk0Zmp0Mk12OUdZeTdrWXp5bFhTQ2cyOE1oZ2VLem9zUlpnZGxxWEcrNGs3bG9aRnd5Q3RmM1wvY2IifQ== x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.0.600.7 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 v5 1/3] rcu: add RCU library supporting QSBR mechanism 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: Mon, 15 Apr 2019 12:24:53 -0000 > -----Original Message----- > From: Stephen Hemminger [mailto:stephen@networkplumber.org] > Sent: Saturday, April 13, 2019 12:06 AM > To: Honnappa Nagarahalli > Cc: Ananyev, Konstantin ; paulmck@linux.ibm= .com; Kovacevic, Marko ; > dev@dpdk.org; Gavin Hu (Arm Technology China) ; Dharmik= Thakkar ; Malvika Gupta > ; nd > Subject: Re: [PATCH v5 1/3] rcu: add RCU library supporting QSBR mechanis= m >=20 > On Fri, 12 Apr 2019 22:24:45 +0000 > Honnappa Nagarahalli wrote: >=20 > > > > > > On Fri, 12 Apr 2019 15:20:37 -0500 > > > Honnappa Nagarahalli wrote: > > > > > > > Add RCU library supporting quiescent state based memory reclamation > > > method. > > > > This library helps identify the quiescent state of the reader threa= ds > > > > so that the writers can free the memory associated with the lock le= ss > > > > data structures. > > > > > > > > Signed-off-by: Honnappa Nagarahalli > > > > Reviewed-by: Steve Capper > > > > Reviewed-by: Gavin Hu > > > > Reviewed-by: Ola Liljedahl > > > > Acked-by: Konstantin Ananyev > > > > > > After evaluating long term API/ABI issues, I think you need to get ri= d of almost > > > all use of inline and visible structures. Yes it might be marginally = slower, but > > > you thank me the first time you have to fix something. > > > > > Agree, I was planning on another version to address this (I am yet to t= ake a look at your patch addressing the ABI). > > The structure visibility definitely needs to be addressed. > > For the inline functions, is the plan to convert all the inline functio= ns in DPDK? If yes, I think we need to consider the performance > difference. May be consider L3-fwd application, change all the inline fun= ctions in its path and run a test? >=20 > Every function that is not in the direct datapath should not be inline. > Exceptions or things like rx/tx burst, ring enqueue/dequeue, and packet a= lloc/free Plus synchronization routines: spin/rwlock/barrier, etc. I think rcu should be one of such exceptions - it is just another synchroni= zation mechanism after all (just a bit more sophisticated). 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 26703A00E6 for ; Mon, 15 Apr 2019 14:24:55 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 04EC31B1EA; Mon, 15 Apr 2019 14:24:54 +0200 (CEST) Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 905D21B1CE for ; Mon, 15 Apr 2019 14:24:52 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Apr 2019 05:24:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,353,1549958400"; d="scan'208";a="149546344" Received: from irsmsx103.ger.corp.intel.com ([163.33.3.157]) by FMSMGA003.fm.intel.com with ESMTP; 15 Apr 2019 05:24:50 -0700 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.31]) by IRSMSX103.ger.corp.intel.com ([169.254.3.30]) with mapi id 14.03.0415.000; Mon, 15 Apr 2019 13:24:47 +0100 From: "Ananyev, Konstantin" To: Stephen Hemminger , Honnappa Nagarahalli CC: "paulmck@linux.ibm.com" , "Kovacevic, Marko" , "dev@dpdk.org" , "Gavin Hu (Arm Technology China)" , Dharmik Thakkar , Malvika Gupta , nd Thread-Topic: [PATCH v5 1/3] rcu: add RCU library supporting QSBR mechanism Thread-Index: AQHU8W09YQlYNBQMIUeythDpmiY2L6Y5BHAAgAAFAYCAAAupgIAEE9Rg Date: Mon, 15 Apr 2019 12:24:47 +0000 Message-ID: <2601191342CEEE43887BDE71AB9772580148A97E53@irsmsx105.ger.corp.intel.com> References: <20181122033055.3431-1-honnappa.nagarahalli@arm.com> <20190412202039.46902-1-honnappa.nagarahalli@arm.com> <20190412202039.46902-2-honnappa.nagarahalli@arm.com> <20190412150650.3709358e@shemminger-XPS-13-9360> <20190412160629.670eacd1@shemminger-XPS-13-9360> In-Reply-To: <20190412160629.670eacd1@shemminger-XPS-13-9360> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNzUxNjcyNDYtYTVlZS00M2Q4LWE1NjQtZmQ2NGJjZDBkMDU3IiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoiUlRxVWtDTGk0Zmp0Mk12OUdZeTdrWXp5bFhTQ2cyOE1oZ2VLem9zUlpnZGxxWEcrNGs3bG9aRnd5Q3RmM1wvY2IifQ== x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.0.600.7 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 v5 1/3] rcu: add RCU library supporting QSBR mechanism 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: <20190415122447.Voz1DjkmWgNypVT7fWZuVgkoc9mVcVDISRNDnB5v3KU@z> > -----Original Message----- > From: Stephen Hemminger [mailto:stephen@networkplumber.org] > Sent: Saturday, April 13, 2019 12:06 AM > To: Honnappa Nagarahalli > Cc: Ananyev, Konstantin ; paulmck@linux.ibm= .com; Kovacevic, Marko ; > dev@dpdk.org; Gavin Hu (Arm Technology China) ; Dharmik= Thakkar ; Malvika Gupta > ; nd > Subject: Re: [PATCH v5 1/3] rcu: add RCU library supporting QSBR mechanis= m >=20 > On Fri, 12 Apr 2019 22:24:45 +0000 > Honnappa Nagarahalli wrote: >=20 > > > > > > On Fri, 12 Apr 2019 15:20:37 -0500 > > > Honnappa Nagarahalli wrote: > > > > > > > Add RCU library supporting quiescent state based memory reclamation > > > method. > > > > This library helps identify the quiescent state of the reader threa= ds > > > > so that the writers can free the memory associated with the lock le= ss > > > > data structures. > > > > > > > > Signed-off-by: Honnappa Nagarahalli > > > > Reviewed-by: Steve Capper > > > > Reviewed-by: Gavin Hu > > > > Reviewed-by: Ola Liljedahl > > > > Acked-by: Konstantin Ananyev > > > > > > After evaluating long term API/ABI issues, I think you need to get ri= d of almost > > > all use of inline and visible structures. Yes it might be marginally = slower, but > > > you thank me the first time you have to fix something. > > > > > Agree, I was planning on another version to address this (I am yet to t= ake a look at your patch addressing the ABI). > > The structure visibility definitely needs to be addressed. > > For the inline functions, is the plan to convert all the inline functio= ns in DPDK? If yes, I think we need to consider the performance > difference. May be consider L3-fwd application, change all the inline fun= ctions in its path and run a test? >=20 > Every function that is not in the direct datapath should not be inline. > Exceptions or things like rx/tx burst, ring enqueue/dequeue, and packet a= lloc/free Plus synchronization routines: spin/rwlock/barrier, etc. I think rcu should be one of such exceptions - it is just another synchroni= zation mechanism after all (just a bit more sophisticated). Konstantin