From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 60871A0535; Tue, 4 Feb 2020 16:06:09 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 6CA101C1EA; Tue, 4 Feb 2020 16:06:08 +0100 (CET) Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) by dpdk.org (Postfix) with ESMTP id 7BED554AE for ; Tue, 4 Feb 2020 16:06:06 +0100 (CET) Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.nyi.internal (Postfix) with ESMTP id 0C3E322011; Tue, 4 Feb 2020 10:06:06 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute1.internal (MEProxy); Tue, 04 Feb 2020 10:06:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s=mesmtp; bh=dKR5zQusCPKtcLV8ppvj15GDVe5rXFZMHa77VzlsPa0=; b=S1M13XYw/87z 5Nkr7+j7LSMkcLf5pr8Fi6eCk37nd4OK4lECu5NG3iMzRxp7YqS/9/CtbNX2Sbta yCt7JfQ+9nw7/LF3qANUqFfJKgNwyMaemCG4zCVd3h2wh1JDjCweaO4vVVo8LyPQ GvGlI5cenhl/txXU51fzykl/lzjfZeg= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm1; bh=dKR5zQusCPKtcLV8ppvj15GDVe5rXFZMHa77VzlsP a0=; b=N/SnNEbNvB9EuYj4J/F5aLlsQxHu9keQb7L/hY7bOVpQq+3g+jA7xgRnf Rh54TInrD5bE67M+L8SyI+8IIggd/fOsRIseRVHwygCBgOACoV2QBmobeog29FBX pbo+jDv0CZkTx7lJZCITEor/qcwO2UTgax1BcqR6IsX6ucYTsk0K/aAYNPHrASKG XlEN9rup9S4kjumG9m5I/jQXO7It5nMUa2p/YUkBNmosq0leMl6yjRNTpjRa0cR8 2Cfaq4o2IxczXDIbRILMBkuSD8PlX8GK674HvnHJHw6GYHsPeBsIsGbAjeAySnVF E7Vx9kSbPXsL8THe7lLIY/Ir8H88Q== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedugedrgeelgdejudcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkjghfggfgtgesthfuredttddtvdenucfhrhhomhepvfhhohhmrghs ucfoohhnjhgrlhhonhcuoehthhhomhgrshesmhhonhhjrghlohhnrdhnvghtqeenucffoh hmrghinhepughpughkrdhorhhgnecukfhppeejjedrudefgedrvddtfedrudekgeenucev lhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehthhhomhgrsh esmhhonhhjrghlohhnrdhnvght X-ME-Proxy: Received: from xps.localnet (184.203.134.77.rev.sfr.net [77.134.203.184]) by mail.messagingengine.com (Postfix) with ESMTPA id E75B930606E9; Tue, 4 Feb 2020 10:06:04 -0500 (EST) From: Thomas Monjalon To: Pavan Nikhilesh Bhagavatula , Gaetan Rivet , Vamsi Krishna Attunuru Cc: David Marchand , dev@dpdk.org, Jerin Jacob Kollanukkaran Date: Tue, 04 Feb 2020 16:06:03 +0100 Message-ID: <4205291.LvFx2qVVIh@xps> In-Reply-To: References: <3503128.aV6nBDHxoP@xps> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [PATCH v7] eal: add manual probing option 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" 04/02/2020 13:43, Gaetan Rivet: > On 04/02/2020 12:07, Thomas Monjalon wrote: > > 04/02/2020 11:03, Gaetan Rivet: > >> On 03/02/2020 23:21, Thomas Monjalon wrote: > >>> 03/02/2020 06:16, Pavan Nikhilesh Bhagavatula: > >>>> @David Marchand @thomas@monjalon.net > >>>> > >>>> Ping? > >>>> > >>>> Are there any more changes required for this patch? It's been in queue since last October. > >>> > >>> Sorry we have not decided whether it is a good idea or not. > >>> > >>> All changes related to probing are very sensitive, > >>> and we know a big refactoring would be better than stacking > >>> more and more options and corner cases. > >>> > >>> As we are busy with ABI stability stuff, we did not allocate > >>> enough time to properly think about this feature. > >>> Please accept our apologies, and let's consider it as > >>> a high priority for 20.05 cycle. > >>> > >> > >> Hello Thomas, > >> > >> This is unfortunate. I pushed Pavan to accept an alternative implementation of this functionality that was less obtrusive, to make the integration smoother. I took care to alleviate those risks from the common path. > >> > >> The big refactoring is needed yes, but considering the current path I'm not seeing it happen in 20.05. If that means taking this patch as-is in 20.05 for Marvell users, I'm not sure much is gained from waiting 3 months, except minimal risk avoidance. > > > > > > Yes, life is full of bad decisions and consequences. > > > Ah, yes, but I stand by my initial opinion, the first implementation [1] was riskier and less useful. > > > > > I still think there is a risk in adding new user expectations, > > and maintaining some code to workaround unknown issues. > > > > The real question here is to know why this patch? > > Is it to workaround a broken driver? > > Or to workaround a broken design in EAL and bus drivers? > > Two birds - one stone here: OVS needed a way to disable automatic probing cleanly (current workaround seen in multiple deployment is to add a dummy whitelisted device, which will be ignored by the PCI bus --> it sets the bus in whitelist mode but avoid probing anything), and as a bonus this option allows using devices that depends on other devices being probed already (LAG, representors, failsafe, etc). > > I'm not sure having a dependent-probe by default is good, and that would be a big change. > > If we are doing the genesis of this patch, the initial motivation should be asked for more details from Marvell people and David for the OVS side. > > [1]: First proposal: > http://mails.dpdk.org/archives/dev/2019-September/144166.html > My arguments: > http://mails.dpdk.org/archives/dev/2019-September/144564.html OK so there are two needs: 1/ Better control whitelist/blacklist mode. We already know that a rework is needed here. Unfortunately neither you or me had time to work on it, and others who were interested disappeared. 2/ Associate ports with equivalent properties in applications. This must be done in applications. Tweaking the probe order is a hack.