From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id B9D6A488F2; Thu, 9 Oct 2025 16:59:00 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 4F729402A0; Thu, 9 Oct 2025 16:59:00 +0200 (CEST) Received: from fhigh-b8-smtp.messagingengine.com (fhigh-b8-smtp.messagingengine.com [202.12.124.159]) by mails.dpdk.org (Postfix) with ESMTP id CB9D340267; Thu, 9 Oct 2025 16:58:58 +0200 (CEST) Received: from phl-compute-05.internal (phl-compute-05.internal [10.202.2.45]) by mailfhigh.stl.internal (Postfix) with ESMTP id C09CA7A0110; Thu, 9 Oct 2025 10:58:57 -0400 (EDT) Received: from phl-mailfrontend-02 ([10.202.2.163]) by phl-compute-05.internal (MEProxy); Thu, 09 Oct 2025 10:58:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= cc:cc:content-transfer-encoding:content-type:content-type:date :date:from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to; s=fm2; t=1760021937; x=1760108337; bh=PHgOIdqk8yDxbpPdT9vjkLWkz3i5pZpW1vBPFFCzfp8=; b= H6VrFir3sPOl2shJ1eWDnI5DmmPu8Qc3lWeOnaOuva7PlP2qeDz9EwH3/iX5ETUh dbVvc0SLjETcK70UpWmQFykZabX3SGDlTcSPMiBR3Ip800ixNpmFWw3/RZV4yctX YCr140WpvuqVr1t4mgn12b93Ifinj/GAb5qv8y/nqgIrKyuW7xLhH7c5U3xDpN1J 9KMryNrGn0mxTQxHE2xEU509nH9vdDTBQjUegrpvgI9tGxai3jcVdHEqulwY/t5X 1XyzzC76jOn+zWgDfhSmIsJwN9HMMjcgR0bKRiLQkCUKsXwNILGuriwa6z+YMFMX UCEh6EjluSSZvaEIeBpODw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:content-type:date:date:feedback-id:feedback-id :from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm2; t=1760021937; x= 1760108337; bh=PHgOIdqk8yDxbpPdT9vjkLWkz3i5pZpW1vBPFFCzfp8=; b=l StkgyAywXDwSIlBc+YfHO/KDl2NfDr6MJdhDeRunJePHV2FqRxpRS2pNiqI/2Y9i S7mEEBSx/vMHiTsLpR+sbL1DnV8rttFvuTRZCMdg0SI2ddZHoDQP5FSNTFdPvIG+ EgJKr65xk3xyDVr1EFvEMZIkKauqO934AGPzuw0cR6ADd6yzZYxlQFv3l0GAUGI+ yvY7Cff35EKa9YZ9nXl8mdLUIAO6YFpAjANelt26KxWjyyM7kvge5ydFPzIed2RG 9IIS4yZuUJTovCOD5ZRjm8ZU1XWw/uJDTlI1rVngxmGeRWVKfzJ3TAnF3Lhe/VRy 4X/ZCPM2cYMbzBnKKlT8Q== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtdeggddutdeigeekucetufdoteggodetrf dotffvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfurfetoffkrfgpnffqhgenuceu rghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujf gurhephffvvefufffkjghfggfgtgesthfuredttddtjeenucfhrhhomhepvfhhohhmrghs ucfoohhnjhgrlhhonhcuoehthhhomhgrshesmhhonhhjrghlohhnrdhnvghtqeenucggtf frrghtthgvrhhnpeejudevheeiveduuddtveffgfdtgeekueevjeffjeegtdeggeekgfdv uefgfeekjeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhroh hmpehthhhomhgrshesmhhonhhjrghlohhnrdhnvghtpdhnsggprhgtphhtthhopeehpdhm ohguvgepshhmthhpohhuthdprhgtphhtthhopegsrhhutggvrdhrihgthhgrrhgushhonh esihhnthgvlhdrtghomhdprhgtphhtthhopegtihgrrhgrrdhlohhfthhushesihhnthgv lhdrtghomhdprhgtphhtthhopehtvggthhgsohgrrhguseguphgukhdrohhrghdprhgtph htthhopeguvghvseguphgukhdrohhrghdprhgtphhtthhopehtihhmohhthhihrdhmihhs khgvlhhlsehinhhtvghlrdgtohhm X-ME-Proxy: Feedback-ID: i47234305:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 9 Oct 2025 10:58:56 -0400 (EDT) From: Thomas Monjalon To: "Richardson, Bruce" , "Loftus, Ciara" Cc: "techboard@dpdk.org" , "dev@dpdk.org" , "Miskell, Timothy" Subject: Re: [PATCH 1/2] net/iavf: support VF initiated resets Date: Thu, 09 Oct 2025 16:58:54 +0200 Message-ID: <2774555.irdbgypaU6@thomas> In-Reply-To: References: <20250929143039.547207-1-ciara.loftus@intel.com> <3977268.0vhOF50zNu@thomas> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org 09/10/2025 12:30, Loftus, Ciara: > > > > 03/10/2025 12:29, Loftus, Ciara: > > > > > > Introduce a function that allows a VF to request the PF to reset itself. > > > > > > This is useful for example when the application detects that one of the > > > > > > queues have hung or any event where a reset is required and the PF is > > > > > > unlikely to trigger it. > > > > > > > > [...] > > > > > > > > > > In general, I'm not a huge fan of adding driver-specific functions and I > > > > > feel like this should fit under the existing reset APIs in some way. That > > > > > should avoid the need to update (or such a big update) to testpmd, for > > > > > example. > > > > > Some thoughts here: > > > > > > > > > > 1. we could add a devarg to the driver to adjust whether reset does a > > > > > "softer" reset of the VF just resetting itself, or a "hard" reset where the > > > > > PF does a fuller reset of the VF. > > > > > 2. rather than a devarg, would do use a driver-specific function to adjust > > > > > this behaviour. The difference here would be that the driver-specific > > > > > function would be an init-time one rather than runtime, so the runtime > > of > > > > > the app, like testpmd, would be generic. > > > > > 3. the most generic solution would be to add an additional parameter to > > the > > > > > reset() function itself to specify a hard or soft reset. This would mean > > > > > updating all drivers to handle the new parameter (shouldn't be hard, > > since > > > > > it would be __rte_unused in all cases by default). This also opens up > > > > > the possibility of other drivers - especially VFs - using it in the same > > > > > way. We could actually document that the "hard" option "may be used > > by > > > > VF > > > > > drivers to request a full reset of the VF by the PF". > > > > > > > > Hi Bruce, > > > > > > > > I did not make it clear in my commit messages the full purpose of this new > > API. > > > > Along with resetting the VF, the VF is also reconfigured and restarted > > > > transparently, using the existing iavf_handle_hw_reset implementation. > > > > While there is probably merit in extending the reset API to include a > > soft/hard > > > > reset flag, I would still need this new API to fulfil the purpose described > > above. > > > > If we wanted to make this generic I see two options: > > > > 1. extend the reset API to optionally reconfigure and restart > > > > 2. introduce a new generic API that performs a reset followed by a > > reconfigure > > > > and restart. > > > > > > I've submitted a v2 and renamed the function to "restore" instead of "reset" > > to > > > better describe the behaviour of the function - not just resetting, but also > > > restoring configuration afterwards and restarting the device. > > > > > > I agree that it would be best to avoid a driver-specific function like this. After > > some > > > thought I don't think we can extend the reset API to include this behaviour, > > the > > > reset API should probably leave the device in a reset state. > > > > > > I'm wondering if the community would be in favour of creating a new ethdev > > API > > > for restoring/reinitialising a device. It would essentially comprise of reset, > > > reconfigure and queue setup, and optionally device start? > > > > It is confusing to add an API if it is a perfect overlap > > of what exists already. > > If you want to add a new API, you need to explain how it is different > > of a combination of reset/configure/start. > > Apologies for any confusion. > The new API would perform only the necessary reconfiguration > and setup steps under-the-hood and use the existing device > configuration. This would differ from a combination of > reset/reconfigure/start in two ways: > 1. In some cases (at least in the case of the iavf driver), a > full rte_eth_dev_configure is not required after an rte_eth_dev_reset. > So the new API could just call the device callbacks for those functions, > rather than forcing the user to call the ethdev functions and perform > some unnecessary reconfiguration steps. > 2. It takes the burden off the user to build up the device configuration > again after the reset. Any pertinent configuration can be stored before > the reset and used to reconfigure the device transparently. All the user > needs to supply is the port id. > > Anyway, I've submitted a v3 of the non-generic version of this for the > iavf driver, so if there is no appetite for the generic approach I'll > continue to pursue the driver-specific one. A generic API is way better. I'm trying to understand what is missing in the current API. I think what you want to achieve is RTE_ETH_ERROR_HANDLE_MODE_PROACTIVE. What is missing exactly to implement it with the generic API?