Date: Thu, 23 Jul 2020 17:02:12 -0700 From: John Baldwin <jhb@FreeBSD.org> To: Alexander Motin <mav@FreeBSD.org>, src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r363188 - in head: lib/libpmc sys/dev/hwpmc Message-ID: <f14bcec8-972e-a108-cce7-04bb7e0d5e0f@FreeBSD.org> In-Reply-To: <e74fefad-64bf-97bd-d0b4-8f1ac0466a30@FreeBSD.org> References: <202007141811.06EIB6b3008168@repo.freebsd.org> <70e7319b-93d6-a9d2-cf70-73a6a26616a5@FreeBSD.org> <e74fefad-64bf-97bd-d0b4-8f1ac0466a30@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On 7/23/20 4:44 PM, 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? I don't see a viable way to do it non-terribly. Assuming you've already MFC'd this it might warrant a line in the release notes for 12.2. -- John Baldwin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?f14bcec8-972e-a108-cce7-04bb7e0d5e0f>