From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by dpdk.org (Postfix) with ESMTP id 6ED341B5F9 for ; Thu, 2 Nov 2017 15:19:42 +0100 (CET) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP; 02 Nov 2017 07:19:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.44,334,1505804400"; d="scan'208";a="916722475" Received: from fmsmsx105.amr.corp.intel.com ([10.18.124.203]) by FMSMGA003.fm.intel.com with ESMTP; 02 Nov 2017 07:19:38 -0700 Received: from fmsmsx101.amr.corp.intel.com ([169.254.1.172]) by FMSMSX105.amr.corp.intel.com ([169.254.4.92]) with mapi id 14.03.0319.002; Thu, 2 Nov 2017 07:19:38 -0700 From: "Eads, Gage" To: Jerin Jacob CC: "dev@dpdk.org" , "Richardson, Bruce" , "Van Haaren, Harry" , Hemant Agrawal , Nipun Gupta , "Rao, Nikhil" , Pavan Nikhilesh , Thomas Monjalon Thread-Topic: [dpdk-dev] [PATCH] eventdev: remove experimental label Thread-Index: AQHTRmpTRlK6K7CWvkG/Xm4GCmCXCqL8vwomgAPVuh+AAKlSgA== Date: Thu, 2 Nov 2017 14:19:37 +0000 Message-ID: <9184057F7FC11744A2107296B6B8EB1E2BAE099E@fmsmsx101.amr.corp.intel.com> References: <20171016103255.16322-1-jerin.jacob@caviumnetworks.com> <9184057F7FC11744A2107296B6B8EB1E1400BE33@FMSMSX108.amr.corp.intel.com> <20171030173803.GA9123@jerin> <9184057F7FC11744A2107296B6B8EB1E1400FA36@FMSMSX108.amr.corp.intel.com> <20171102041152.GA2107@jerin> In-Reply-To: <20171102041152.GA2107@jerin> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiMDc5MDU2ZmUtZGMzOC00NzQ1LTgxYTctZDg1M2VlNGMyMzZkIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE2LjUuOS4zIiwiVHJ1c3RlZExhYmVsSGFzaCI6Im9pb0FZMjZqV1JZdmNCemVMdUZNc29jaHBJNDZVT0dzZWNVamlBOHU4TU09In0= x-ctpclassification: CTP_IC dlp-product: dlpe-windows dlp-version: 11.0.0.116 dlp-reaction: no-action x-originating-ip: [10.1.200.106] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH] eventdev: remove experimental label 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: Thu, 02 Nov 2017 14:19:43 -0000 > -----Original Message----- > From: Jerin Jacob [mailto:jerin.jacob@caviumnetworks.com] > Sent: Wednesday, November 1, 2017 11:12 PM > To: Eads, Gage > Cc: dev@dpdk.org; Richardson, Bruce ; Van > Haaren, Harry ; Hemant Agrawal > ; Nipun Gupta ; Rao, > Nikhil ; Pavan Nikhilesh > ; Thomas Monjalon > > Subject: Re: [dpdk-dev] [PATCH] eventdev: remove experimental label >=20 > -----Original Message----- > > Date: Wed, 1 Nov 2017 14:12:59 +0000 > > From: "Eads, Gage" > > To: Jerin Jacob > > CC: "dev@dpdk.org" , "Richardson, Bruce" > > , "Van Haaren, Harry" > > , Hemant Agrawal > > , Nipun Gupta , "Rao, > > Nikhil" , Pavan Nikhilesh > > , Thomas Monjalon > > > > Subject: RE: [dpdk-dev] [PATCH] eventdev: remove experimental label > > > > > > > > > -----Original Message----- > > > From: Jerin Jacob [mailto:jerin.jacob@caviumnetworks.com] > > > Sent: Monday, October 30, 2017 12:38 PM > > > To: Eads, Gage > > > Cc: dev@dpdk.org; Richardson, Bruce ; > > > Van Haaren, Harry ; Hemant Agrawal > > > ; Nipun Gupta ; Rao, > > > Nikhil ; Pavan Nikhilesh > > > ; Thomas Monjalon > > > > > > Subject: Re: [dpdk-dev] [PATCH] eventdev: remove experimental label > > > > > > -----Original Message----- > > > > Date: Mon, 23 Oct 2017 18:27:52 +0000 > > > > From: "Eads, Gage" > > > > To: Jerin Jacob , "dev@dpdk.org" > > > > > > > > CC: "Richardson, Bruce" , "Van Haaren, > Harry" > > > > , Hemant Agrawal > > > > , Nipun Gupta , > > > > "Rao, Nikhil" , Pavan Nikhilesh > > > > , Thomas Monjalon > > > > > > > > Subject: RE: [dpdk-dev] [PATCH] eventdev: remove experimental > > > > label > > > > > > > > Hi Jerin, > > > > > > Hi Gage, > > > > > > > > > > > I have one concern with the API that may delay changing the label. > > > > > > > > The implicit release that in rte_event_dequeue_burst() is a > > > > problem when using > > > asynchronous/look-aside hardware, like a cryptodev. For instance, > > > let's say in pipeline stage N the worker takes the event's mbuf and > > > places it in a per-worker crypto request queue. When the worker next > > > calls rte_event_dequeue_burst(), that function will release the > > > previous event which could cause the flow to migrate to another worke= r, > and this could result in packet reordering. > > > > > > > > To prevent this, the worker can't call dequeue until the > > > > look-aside operation > > > completes...in effect treating the asynchronous/look-aside hardware > > > as synchronous. Another option is to feed stage N's queue to a > > > single port to avoid the flow migration, but that port may become a > bottleneck. > > > > > > > > We could remove the implicit release functionality or add a port > > > > configuration > > > flag to disable it, so the default behavior is unchanged. Removing > > > it will completely will likely require changes in existing code, but > > > it simplifies the usage model (all dequeued events must be either > > > forwarded or released) and the PMD's dequeue code. This > > > functionality could be removed from the software eventdev fairly easi= ly, but > I haven't looked into the hardware PMDs. > > > > > > > > > > > > The HW implementations, I know, it does the implicit release. > > > Otherwise it will result in deadlock because it cannot hold > > > reordering metadata for the longtime(SRAM is limited etc) > > > > > > Coming back to cryptodev use case, if I understand it correctly, > > > before application enqueues to crypto queue, the application will > > > change the tag and submit to ATOMIC queue. So as long as crypto > > > queue competes for the crypto work in order then the order will be > maintained. > > > > > > In typical outbound IPSec use case, > > > - Stage 1 will be processed in ORDERED where application does the SA > > > lookup > > > - Once SA found, application enqueue to ATOMIC stage with SA as flow_= id. > > > - When the event comes from the ATOMIC queue, it in ingress order and > > > then it submits to the crypto queue > > > - Crypto queue maintains the FIFO order. > > > - On IPSec crypto work competition, packets will come in Stage 3. > > > - So at Stage 3, packets are in ingress order for the given SA flow i= d. > > > > > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > > > > > Having said that, If SW implementation needs to do differently for > > > performance reasons then we will end up in capability as HW > > > implementation works in the implicit release. May we can sort out > > > through capability or separate adapter for crypto case. But I think, > > > those will be new additions to the API.So removing the experimental t= ags > may be OK. > > > But if you have strong opinion on keeping the experimental tag till > > > we address the crypto use case then I am fine with that. > > > > > > Thoughts? > > > > Ok, agreed, no need to keep the tag for this concern. The capability id= ea is > intriguing -- I'll chew on this and we can tackle it at a later point. >=20 > OK. Please add Acked-by: >=20 Sure. Acked-by: Gage Eads > > > > Thanks, > > Gage > > > > > > > > Jerin > > > > > > > > > > > > > > Thanks, > > > > Gage > > > >