From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Williams Subject: Re: [PATCH v2 16/17] x86/insn: remove pcommit Date: Fri, 22 Jul 2016 17:54:46 -0700 Message-ID: References: <146812106839.32932.2870621200867047059.stgit@dwillia2-desk3.amr.corp.intel.com> <146812115425.32932.3314855641604340233.stgit@dwillia2-desk3.amr.corp.intel.com> <20160712145757.GV30909@twins.programming.kicks-ass.net> <20160722165246.GA24884@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <20160722165246.GA24884@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org To: Ingo Molnar Cc: Peter Zijlstra , linux-nvdimm , Xiao Guangrong , Josh Poimboeuf , Linux ACPI , "linux-kernel@vger.kernel.org" , X86 ML , Adrian Hunter , Arnaldo Carvalho de Melo , Christoph Hellwig , Alexander Shishkin , Ingo Molnar , Andy Lutomirski , "H. Peter Anvin" , linux-fsdevel , Thomas Gleixner , Borislav Petkov , Ross Zwisler List-Id: linux-acpi@vger.kernel.org On Fri, Jul 22, 2016 at 9:52 AM, Ingo Molnar wrote: > > * Dan Williams wrote: > >> On Tue, Jul 12, 2016 at 3:12 PM, Dan Williams wrote: >> > On Tue, Jul 12, 2016 at 7:57 AM, Peter Zijlstra wrote: >> >> On Sat, Jul 09, 2016 at 08:25:54PM -0700, Dan Williams wrote: >> >>> The pcommit instruction is being deprecated in favor of either ADR >> >>> (asynchronous DRAM refresh: flush-on-power-fail) at the platform level, or >> >>> posted-write-queue flush addresses as defined by the ACPI 6.x NFIT (NVDIMM >> >>> Firmware Interface Table). >> >> >> >>> arch/x86/include/asm/cpufeatures.h | 1 >> >>> arch/x86/include/asm/special_insns.h | 46 -------------------- >> >>> arch/x86/lib/x86-opcode-map.txt | 2 - >> >>> tools/objtool/arch/x86/insn/x86-opcode-map.txt | 2 - >> >>> tools/perf/arch/x86/tests/insn-x86-dat-32.c | 2 - >> >>> tools/perf/arch/x86/tests/insn-x86-dat-64.c | 2 - >> >>> tools/perf/arch/x86/tests/insn-x86-dat-src.c | 4 -- >> >> >> >> Just deprecated, or is it completely eradicated, removed from history, >> >> will never ever happen and we'll reissue the opcode for something else? >> >> >> >> Because if its only deprecated then removing it from the instruction >> >> decoders seems wrong, old binaries might still contain the opcode. >> > >> > Eradicated. >> > >> > "The new instructions like CLWB and CLFLUSHOPT will be rolled into the >> > SDM but PCOMMIT will be removed from the Extensions doc and not rolled >> > into the SDM." [1] >> > >> > Existing binaries are already gating their usage on the presence of >> > the cpu id flag, that flag and the instruction opcode are reserved >> > going forward. >> > >> > [1]: https://lists.01.org/pipermail/linux-nvdimm/2016-June/005923.html >> >> x86 maintainers, I have the other patches in this series queued in -next. Please >> ack this one and I'll add it for v4.8-rc1, or otherwise let me know how you want >> to handle this patch. > > Since it's just a removal AFAICS that the rest of your series should not depend > on, can you submit it to the x86 tree? This patch depends on the previous patches in the series removing calls to pcommit_sfence().