From owner-svn-src-all@freebsd.org Thu Jul 23 23:47:40 2020 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D39B23676C3; Thu, 23 Jul 2020 23:47:40 +0000 (UTC) (envelope-from mjguzik@gmail.com) Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4BCTXX5JNRz4JvS; Thu, 23 Jul 2020 23:47:40 +0000 (UTC) (envelope-from mjguzik@gmail.com) Received: by mail-wr1-x444.google.com with SMTP id b6so6692707wrs.11; Thu, 23 Jul 2020 16:47:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=GB8C7WKLa0GBJSBhu7Jpio9r5sGKZGUC/oyWAjSBxdw=; b=QrRTfFEuNrGrfHYVHbMMytnlaIx8qN3uh+hIlc5si8wlrEis0BwUTk7T+y7t2hzlwW +1jrMk+X+zmgs/Tj2YixvkD5Aj3IuX7Qe9yUmZDDjnmUYLYZkdvunsHqEX9b+3O7Z3Yv 02WT+ihTVUoXIuwOyvn31GRn8YYKSVDYWNAK5X+a1+ujGXMrPuJ6fLLWIka4ig1IXcU9 IvAx274Og8PSWTyk3S170cIxW0/dJp8pUN26e2bFMcJFjLa7TnRbejaq4Gg2qhesFiPt D/DV4JjdzOBYBbq30K39yIuLx6SWxeqGUyJs4/+y5aVtYNSw+/ipzGVW1DZAUnzKFsgs 1ttA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=GB8C7WKLa0GBJSBhu7Jpio9r5sGKZGUC/oyWAjSBxdw=; b=maouhb948eNOMdTI71K0dxIeJGN/TpgOlNShYm/lHl0Kjk/ffoR+OmWtaWVGqYYVAo vsSSsP2Lb/GxYS0cHnkXWckDmGGV55E07aVBZhWr5fc3e+38d/voZHVDZf/h9cc3b6Mf TFx4FV9Ft+pJ8mi1f4Cza2u272NkaVtZC5MrcS3Xj7yf2eZDToX2roQq6dE+y+7T2I38 M/EWma4I5f/mZNnjuwdGi/2moF2mi7reU9jdPOQdrSp+N2+dAou4ovJ5znjrL8fEoyPt pGce3ohbSIoPOQi5Df2ToqS8r7VCXHGsU9FDbfeHLbfXc+GazY+CzZM5RXsGEycOj+eG bF+A== X-Gm-Message-State: AOAM5315KXM3B03aIAQLYd1Uj2Rpbt/NcHxF0by9349hA//ksspZS9PD eIr6D/jzZ2OThHu8uYndSohW3IzHvIqU3Qe6vZ5d9A== X-Google-Smtp-Source: ABdhPJyFx6gsYaGL05OM9oqZutLv5+/9R7U0bjqO9M2O4z+TUhESi3yEota3Rizf1m35qhBrBzGZYTjZEOAU//Md0eU= X-Received: by 2002:adf:82b2:: with SMTP id 47mr5857210wrc.17.1595548059237; Thu, 23 Jul 2020 16:47:39 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a5d:614c:0:0:0:0:0 with HTTP; Thu, 23 Jul 2020 16:47:38 -0700 (PDT) In-Reply-To: References: <202007141811.06EIB6b3008168@repo.freebsd.org> <70e7319b-93d6-a9d2-cf70-73a6a26616a5@FreeBSD.org> From: Mateusz Guzik Date: Fri, 24 Jul 2020 01:47:38 +0200 Message-ID: Subject: Re: svn commit: r363188 - in head: lib/libpmc sys/dev/hwpmc To: Alexander Motin Cc: John Baldwin , src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 4BCTXX5JNRz4JvS X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; REPLY(-4.00)[] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Jul 2020 23:47:40 -0000 I don't think that's worth the effort. However, versioning would be nice. Then tooling could nicely crap out immediately instead of giving funny results (or no results). On 7/24/20, Alexander Motin wrote: > On 23.07.2020 19:15, John Baldwin wrote: >> On 7/14/20 11:11 AM, Alexander Motin wrote: >>> Author: mav >>> Date: Tue Jul 14 18:11:05 2020 >>> New Revision: 363188 >>> URL: https://svnweb.freebsd.org/changeset/base/363188 >>> >>> Log: >>> Add stepping to the kern.hwpmc.cpuid string on x86. >>> >>> It follows the equivalent Linux change to be able to differentiate >>> skylakex and cascadelakex, sharing the same model but not stepping. >>> >>> This fixes skylakex handling broken by r363144. >> >> Unfortunately this breaks compatibility meaning you can't use an older >> libpmc with a newer kernel module after this change. Perhaps we don't >> consider libpmc stable, but this was really annoying as I booted a test >> kernel today on an older Haswell box whose world is from before this >> change and pmc doesn't work at all. (pmccontrol -L doesn't list any >> valid counters as the older libpmc presumably chokes on the additional >> suffix and doesn't match anything) > > Unfortunately so. I've added other way compatibility, but can't change > the past. Do you think it is critical enough to add more compat shims, > like extra sysctls? > > -- > Alexander Motin > -- Mateusz Guzik