From nobody Wed Jan 05 19:19:37 2022 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 232E8192616D; Wed, 5 Jan 2022 19:19:40 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from smtp.freebsd.org (smtp.freebsd.org [96.47.72.83]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "smtp.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4JTfSC73jrz4Z46; Wed, 5 Jan 2022 19:19:39 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from [10.0.1.4] (ralph.baldwin.cx [66.234.199.215]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) (Authenticated sender: jhb) by smtp.freebsd.org (Postfix) with ESMTPSA id 41CE95A3; Wed, 5 Jan 2022 19:19:39 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Message-ID: <76cbd1de-3a05-b64f-57e7-6189182c1129@FreeBSD.org> Date: Wed, 5 Jan 2022 11:19:37 -0800 List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-main@freebsd.org X-BeenThere: dev-commits-src-main@freebsd.org MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:91.0) Gecko/20100101 Thunderbird/91.4.1 Content-Language: en-US To: Warner Losh , Alexander Motin Cc: src-committers , dev-commits-src-all@freebsd.org, dev-commits-src-main@freebsd.org References: <202201051641.205GfWZV041757@gitrepo.freebsd.org> From: John Baldwin Subject: Re: git: 9e007a88d65b - main - atkbd: Reduce polling rate from 10Hz to ~1Hz. In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1641410380; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NmD/otZWZliz066gfm8ZiAN+irrbUJW4Na0elRt1ZgU=; b=ZdJ/EPRotm/nUIFHAavefL8jQ2U904QtrkQFq3M70rP+o9C4XmCeMQzGgPfQLhbiXJjSKB f9AZ2i5j/SOW8Y6flOOOkCqy7DOFDuLXDUyvEzX3FZwxp4stcUnTyw5KyCBr8jCHWTv6h+ SIf6PMiuknjpbHCIlCMI3Gm29U8SUCMrzDV2XTwbx0zA3K+myass8WTFnktlMw3A9SMqs0 hbrJT/dg7rQdXkoBC711C9FD2cMYE4mulUjK9+VDQAxMKfd8Nx3hRE4ssBuU0ULQggPmN8 66rCMGsA/5SorhEyHkKBqJ5gn9WvK65fxmumsIBuGkYdSv2fcVWWTNI4WnIa0A== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1641410380; a=rsa-sha256; cv=none; b=DtFOM/Rdfl04FPUNTt4kWF8B0DsNo6lLfIz6xo8Ufb+EPUWSWonuubTcjYx9d4fVFmXC2Y 7S2B84QK66iaOw2hxv8DkXNQKkgjcSGn5HhklQBggGtn1TPNtCxUCYmzbsetJqLvJgUedB dwkXZp+Z2yyGoI/CHRWh+mndgCRuqm7uy20RdjCN8iEFfkNqt4Hh3pyErncn1WfEiai2V2 ZpOR4+mokRt4YRuOvt1kFHZOjNmYqYdYQ9O6jdBEBouW8cPAcVjKodNFCvi/EY+l82noEH xlIS8qk/YKCuz1tU7hsAkRw3gc5isJtNON7YuNwVSNuEWO12G6K32FksSA3pGQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none X-ThisMailContainsUnwantedMimeParts: N On 1/5/22 9:26 AM, Warner Losh wrote: > Maybe we default hw.atkbd.hz to 0. That will give us more info if this is > even a thing still. And it would give users hit by this a no recompile fix > and give us feedback as to how often this happens. > > We used to miss ISA interrupts in the early SMPNG days, and that's the time > this change was introduced. The PIC does a good job of latching the state > and we have no other drivers that have this workaround absent issues with > the device itself. This is much older than SMPng. The original commit to add this is: commit 10661203e7e5727c16d3ecbb15c819837d6ad176 Author: Søren Schmidt Date: Mon Nov 4 21:01:08 1996 +0000 Fix the hanging keyboard problem under Xaccel. Apprently we are loosing an interrupt somewhere. The solution here is to check for keyboard input each time the screen update timer ticks. Not pretty, but works. ISA interrupts have always been edge triggered, though in theory even in pre-SMPng we should have set a bit in the mask of pending hardware interrupts and re-ran the interrupt handler after it returned anytime an interrupt arrived while the handler was running (if I understand the pre-SMPng interrupt management correctly). That said, I somewhat doubt that this is still an actual bug today. I think you could just leave this set to 0 by default. -- John Baldwin