Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761144AbcKDKwk (ORCPT ); Fri, 4 Nov 2016 06:52:40 -0400 Received: from mail.skyhub.de ([78.46.96.112]:50043 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754700AbcKDKwj (ORCPT ); Fri, 4 Nov 2016 06:52:39 -0400 Date: Fri, 4 Nov 2016 11:52:35 +0100 From: Borislav Petkov To: He Chen Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Luwei Kang , Piotr Luc Subject: Re: [PATCH v3] x86/cpuid: expose AVX512_4VNNIW and AVX512_4FMAPS features to kvm guest Message-ID: <20161104105235.qbqvmsv4ikajvjtu@pd.tnic> References: <1478243239-15586-1-git-send-email-he.chen@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1478243239-15586-1-git-send-email-he.chen@linux.intel.com> User-Agent: NeoMutt/20161014 (1.7.1) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3937 Lines: 139 Please CC me on your future submissions, thanks. On Fri, Nov 04, 2016 at 03:07:19PM +0800, He Chen wrote: > The spec can be found in Intel Software Developer Manual or in > Instruction Set Extensions Programming Reference. This commit message is completely useless. Write commit messages in the way as if you're explaining to another person *why* this change is needed and that other person doesn't have an idea what you're doing. > Signed-off-by: Luwei Kang > Signed-off-by: He Chen This SOB chain means what exactly? > --- > Changes in v3: > * add a helper in scattered.c to get scattered leaf. The modification to scattered et al without the kvm use should be a separate patch. > * Capabilities of Intel PT hardware, such as number of address bits or > * supported output schemes, are cached and exported to userspace as "caps" > diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h > index 984a7bf..47978b7 100644 > --- a/arch/x86/include/asm/processor.h > +++ b/arch/x86/include/asm/processor.h > @@ -137,6 +137,13 @@ struct cpuinfo_x86 { > u32 microcode; > }; > > +enum cpuid_regs_idx { cpuid_regs was just fine. > + CR_EAX = 0, > + CR_ECX, > + CR_EDX, > + CR_EBX > +}; > + > #define X86_VENDOR_INTEL 0 > #define X86_VENDOR_CYRIX 1 > #define X86_VENDOR_AMD 2 > @@ -178,6 +185,8 @@ extern void identify_secondary_cpu(struct cpuinfo_x86 *); > extern void print_cpu_info(struct cpuinfo_x86 *); > void print_cpu_msr(struct cpuinfo_x86 *); > extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c); > +extern u32 get_scattered_cpuid_leaf(unsigned int level, > + unsigned int sub_leaf, enum cpuid_regs_idx reg); Align arguments on the opening brace like this: extern u32 get_scattered_cpuid_leaf(unsigned int level, unsigned int sub_leaf, enum cpuid_regs_idx reg); > extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c); > extern void init_amd_cacheinfo(struct cpuinfo_x86 *c); > > diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c > index 1db8dc4..ca3c605 100644 > --- a/arch/x86/kernel/cpu/scattered.c > +++ b/arch/x86/kernel/cpu/scattered.c > @@ -17,11 +17,17 @@ struct cpuid_bit { > u32 sub_leaf; > }; > > -enum cpuid_regs { > - CR_EAX = 0, > - CR_ECX, > - CR_EDX, > - CR_EBX > +/* Please keep the leaf sorted. */ ... by cpuid_bit.level for faster search. */ > +static const struct cpuid_bit cpuid_bits[] = { > + { X86_FEATURE_APERFMPERF, CR_ECX, 0, 0x00000006, 0 }, > + { X86_FEATURE_EPB, CR_ECX, 3, 0x00000006, 0 }, > + { X86_FEATURE_INTEL_PT, CR_EBX, 25, 0x00000007, 0 }, > + { X86_FEATURE_AVX512_4VNNIW, CR_EDX, 2, 0x00000007, 0 }, > + { X86_FEATURE_AVX512_4FMAPS, CR_EDX, 3, 0x00000007, 0 }, > + { X86_FEATURE_HW_PSTATE, CR_EDX, 7, 0x80000007, 0 }, > + { X86_FEATURE_CPB, CR_EDX, 9, 0x80000007, 0 }, > + { X86_FEATURE_PROC_FEEDBACK, CR_EDX, 11, 0x80000007, 0 }, > + { 0, 0, 0, 0, 0 } > }; ... > @@ -57,3 +51,27 @@ void init_scattered_cpuid_features(struct cpuinfo_x86 *c) > set_cpu_cap(c, cb->feature); > } > } > + > +u32 get_scattered_cpuid_leaf(unsigned int level, unsigned int sub_leaf, > + enum cpuid_regs_idx reg) Align arguments on the opening brace. > +{ > + u32 cpuid_val = 0; > + const struct cpuid_bit *cb; Please sort function local variables declaration in a reverse christmas tree order: longest_variable_name; shorter_var_name; even_shorter; i; > + > + for (cb = cpuid_bits; cb->feature; cb++) { > + > + if (level > cb->level) > + continue; > + > + if (level < cb->level) > + break; > + > + if (reg == cb->reg && sub_leaf == cb->sub_leaf) { > + if (cpu_has(&boot_cpu_data, cb->feature)) > + cpuid_val |= BIT(cb->bit); > + } > + } > + > + return cpuid_val; > +} -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.