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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F3CBC433FE for ; Fri, 19 Nov 2021 16:11:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0989261B27 for ; Fri, 19 Nov 2021 16:11:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236264AbhKSQOO (ORCPT ); Fri, 19 Nov 2021 11:14:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234964AbhKSQON (ORCPT ); Fri, 19 Nov 2021 11:14:13 -0500 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC478C061574 for ; Fri, 19 Nov 2021 08:11:11 -0800 (PST) Received: by mail-ed1-x529.google.com with SMTP id r25so7822277edq.7 for ; Fri, 19 Nov 2021 08:11:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:mail-followup-to:references :mime-version:content-disposition:in-reply-to; bh=KIgonA2EFTJLKTGv6+UD7Og9LS6eD0ftI5Kt9N5ampc=; b=dgWOaaq8yzIV1gHvfhemyZzO0QeUnPQPv8uVRZXUwjLioj3Hwn6siTvzHlaMIZ+M10 7tJHjRqw94twP/WJGnDKvc9Tmz0Fn6Yc9Vvt+pm9yC4Sy11voNWpvPXPuV5NiIR23tEp 5UPYM6qyrV8lv4YGUd8iuMlwg7TcUyXij0cLY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id :mail-followup-to:references:mime-version:content-disposition :in-reply-to; bh=KIgonA2EFTJLKTGv6+UD7Og9LS6eD0ftI5Kt9N5ampc=; b=TL7tXxgd+6g/M44KfK/o4yIJwGgabgsDml8VY0xeT676klb7sSZjSx6TWGJpx86DQN cgBsYORjAGoMkBq/0NUcdIqmPpmzfn+IpoesHsA6+JpXWUQUcQBpG/2HFg8Pc4IdhjLc Hs8KJtPn9NG0aOrbRIEOdFO2MVqmy4Fx1bJkSDdrgz9hW6ouCELDcusChSplepzfROSx /IQPwA5vZIc0F0dK1KuVi665xoC0ccNtEHlj50q7y9HzFmRjRVGgRGYqL8H19+PTH1bU 9/R8bQFQRcTWQlPg6bYMjoOT5qDtt4uXXmaQrLAsbTSsr6bbdlFPBs9zaMPAhtbdg63v BJbw== X-Gm-Message-State: AOAM532voxHbzm/9pLCG5M1L+ucd0H2EiLcCtyzuCCJ3cydJPRYuUWWo ufXkocZ6d2hD4BvFeNJsteBqZA== X-Google-Smtp-Source: ABdhPJxdLdSV5agM8x3vcedpr+NqChZx9RvCft+FI62Knox080qmHnRF7sNgy7+mWO4QtRIMEi9PDQ== X-Received: by 2002:a05:6402:268d:: with SMTP id w13mr26820359edd.257.1637338270326; Fri, 19 Nov 2021 08:11:10 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id u16sm128924ejy.16.2021.11.19.08.11.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Nov 2021 08:11:09 -0800 (PST) Date: Fri, 19 Nov 2021 17:11:07 +0100 From: Daniel Vetter To: Simon Ser Cc: Daniel Vetter , Pekka Paalanen , Rob Clark , Brian Norris , Andrzej Hajda , David Airlie , Dmitry Torokhov , Linux Kernel Mailing List , dri-devel , Doug Anderson , "open list:ARM/Rockchip SoC..." , "Kristian H . Kristensen" , Thomas Zimmermann , linux-input@vger.kernel.org Subject: Re: [PATCH v2 1/2] drm/input_helper: Add new input-handling helper Message-ID: Mail-Followup-To: Simon Ser , Pekka Paalanen , Rob Clark , Brian Norris , Andrzej Hajda , David Airlie , Dmitry Torokhov , Linux Kernel Mailing List , dri-devel , Doug Anderson , "open list:ARM/Rockchip SoC..." , "Kristian H . Kristensen" , Thomas Zimmermann , linux-input@vger.kernel.org References: <20211117224841.3442482-1-briannorris@chromium.org> <20211117144807.v2.1.I09b516eff75ead160a6582dd557e7e7e900c9e8e@changeid> <20211118123928.545dec8a@eldfell> <20211119115419.505155b5@eldfell> <98236dpcx39iOz8xAYrwGLfiLdwgUlljrbBgHL3wd8A0Wz4KzRk3PR8s_tb5Rxu4eScKI4483kB6Vhv-T64CJYOeQqwXlqo2c-64HvoS5cg=@emersion.fr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <98236dpcx39iOz8xAYrwGLfiLdwgUlljrbBgHL3wd8A0Wz4KzRk3PR8s_tb5Rxu4eScKI4483kB6Vhv-T64CJYOeQqwXlqo2c-64HvoS5cg=@emersion.fr> X-Operating-System: Linux phenom 5.10.0-8-amd64 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 19, 2021 at 04:04:28PM +0000, Simon Ser wrote: > On Friday, November 19th, 2021 at 16:53, Daniel Vetter wrote: > > > Random idea ... should we perhaps let userspace connect the boosting? I.e. > > we do a bunch of standardized boost targets (render clocks, display sr > > exit), and userspace can then connect it to whichever input device it > > wants to? > > On IRC we discussed having user-space hand over a FD to the kernel. When the FD > becomes readable, the kernel triggers the boost. > > This would let user-space use e.g. an input device, an eventfd, or an epoll FD > with any combination of these as the boost signal. Can userspace filter eventfd appropriately like we do here? And can they get at that maybe 2nd eventfd from logind or whatever there is on distros where /dev access is locked down for compositors/users. I do agree that if we can do this generically maybe we should, but also the use-case for input boosting is pretty well defined. I think it's just about making sure that compositors is in control, and that we don't make it worse (e.g. with the sr exit adding latency when the compositor can redraw quickly enough). -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch