From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E901C43334 for ; Thu, 21 Jul 2022 11:30:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233161AbiGULaf (ORCPT ); Thu, 21 Jul 2022 07:30:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229866AbiGULad (ORCPT ); Thu, 21 Jul 2022 07:30:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7AFC2CE24 for ; Thu, 21 Jul 2022 04:30:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 52F1361AAC for ; Thu, 21 Jul 2022 11:30:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3EB09C3411E; Thu, 21 Jul 2022 11:30:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1658403031; bh=gIU05DjFlkodFloAR0LapBs8EY/oYW4Iwpe7LC1pqac=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IZLO9qZOzZQ2f8axx0+Wh0wpg9T8anGP6Mym+njmlF2fBkHNS8f8V/rdQtsxtzcRa MtPqMFL8z22wwfxOCdjj+dwwSuhhg8ogObkzHbhS5RoOhe7pMUYdh2yOMYJWY1ZQZI aOGuA4IRA6O8SDAAnSqxGOSHgeNtQia9A9CcqKjmGvZ1LFoFrRSXyINTjicUiAAzS1 Kaw1Bb43dB05oOsNcbiRlZuIsWLzdKXBNP6sJ6ywyjUXW5Y7fsdmEZQ+3F2kU8PcAf OE9YoWviYYqcnhK4mbiWHf6wguhvr+/A20/zoiiDbhg0Le0G6RK3UgSvxHGCDIbs3Q lm74OjMMtUeBw== Date: Thu, 21 Jul 2022 12:30:18 +0100 From: Lee Jones To: "Russell King (Oracle)" Cc: Sudeep Holla , Saravana Kannan , Philipp Zabel , Rob Herring , Ulf Hansson , Linus Walleij , Nicolas Saenz Julienne , Geert Uytterhoeven , Marek Szyprowski , Kefeng Wang , Greg Kroah-Hartman , kernel-team@android.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5] amba: Remove deferred device addition Message-ID: References: <20220719182010.637337-1-saravanak@google.com> <20220720131221.azqfidkry3cwiarw@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 21 Jul 2022, Russell King (Oracle) wrote: > On Wed, Jul 20, 2022 at 02:12:21PM +0100, Sudeep Holla wrote: > > On Tue, Jul 19, 2022 at 11:20:10AM -0700, Saravana Kannan wrote: > > > The uevents generated for an amba device need PID and CID information > > > that's available only when the amba device is powered on, clocked and > > > out of reset. So, if those resources aren't available, the information > > > can't be read to generate the uevents. To workaround this requirement, > > > if the resources weren't available, the device addition was deferred and > > > retried periodically. > > > > > > However, this deferred addition retry isn't based on resources becoming > > > available. Instead, it's retried every 5 seconds and causes arbitrary > > > probe delays for amba devices and their consumers. > > > > > > Also, maintaining a separate deferred-probe like mechanism is > > > maintenance headache. > > > > > > With this commit, instead of deferring the device addition, we simply > > > defer the generation of uevents for the device and probing of the device > > > (because drivers needs PID and CID to match) until the PID and CID > > > information can be read. This allows us to delete all the amba specific > > > deferring code and also avoid the arbitrary probing delays. > > > > > > Cc: Rob Herring > > > Cc: Ulf Hansson > > > Cc: Saravana Kannan > > > Cc: Linus Walleij > > > Cc: Sudeep Holla > > > > Tested-by: Sudeep Holla > > > > on Juno with linux-next(which had the reported issue [1]) + this patch(which > > fixes the issue) > > Ok, but this patch needs to end up in the patch system for me to apply > it. Can someone please add "KernelVersion: 5.19-rc7" or whatever version > the patch was generated against (just the tagged version is sufficient) > somewhere in the email, and send it to patches@armlinu.org.uk. If this is a part of the submission process for the subsystems/files you maintain, do you think it would be worth while adding this address to MAINTAINERS to make it easier for future contributors?