From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A520C19F2D for ; Thu, 4 Aug 2022 08:49:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236085AbiHDItZ (ORCPT ); Thu, 4 Aug 2022 04:49:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52958 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232080AbiHDItV (ORCPT ); Thu, 4 Aug 2022 04:49:21 -0400 Received: from mail-pf1-x429.google.com (mail-pf1-x429.google.com [IPv6:2607:f8b0:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AB58EC3F; Thu, 4 Aug 2022 01:49:17 -0700 (PDT) Received: by mail-pf1-x429.google.com with SMTP id 17so18824906pfy.0; Thu, 04 Aug 2022 01:49:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=YuZgAf9eJDiIQ1pfzGSgYaDFUDPS+whO4VhSlSI0bQI=; b=Nmc3YZfbiVDljfe1S3Nnwdzg+Heu9NiAzb8XYTDkWy//pJAFpCxwgfFeLQf2ohvT/e mFW7ObPEdj0F3bnRJeesXm2sulwWEH/fC4xRE1xeyPCZApTHvR1I+OV17k7a/gAJ/1m8 6mZ+FkdlsDjiA7CatUJuQmtJaC0KKnO/koGR5mJOLAS942loviG+34p3x7vSykD4xFlJ fTqe49yQlWYEfucrNvf1To1zhNLim+Q2z8++lkfY0C+d+++st5vFrouiFj39nqKn0hGs zrErSeX9TCxrqnrEcxd7WK7KfJd9y6v7+2Jh/DrFSyMglhHV/7Qh7XCcxMd6YMHqS+t5 eGXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=YuZgAf9eJDiIQ1pfzGSgYaDFUDPS+whO4VhSlSI0bQI=; b=b3Axv2Eng02YYx8gZi54WVuEjncGMpz3Qbk3mPAoua9OGPw/dCrblNNZ+Hyi69RiW8 GMQL6egs8rPCtZ4wn4wFqAyfwNq35klYVVilXqmLlYcq8zQRa/IgREQ8F7cVb1aZduVE OO5LAzLc0JQ5LPHXgkjhL82650pB0zaZi5NIEVtBpNVnOiW7bh3Q93DYjhszaOVVyxwA xWj9VQLyNgTGoSAf3ZiPScbddFv1EwDHKeDiONCM1cyFoYkJNeixFNWj/rG0KBROI8Sc lb6PwWt7hU7Q+ppsuAAzBU1zI3RoSFdYvMq61P7bK6XPrrmwq6B/7UOxjE5r0xUWFpvv ketA== X-Gm-Message-State: ACgBeo01Ds+uPTLUn2RMx5TvrAfS1AZniJKI6Xd2EspeZWUYyxv83Fdj H2uIMWqrs+3M+AWkGQbY/J4= X-Google-Smtp-Source: AA6agR6f3u0cPfCCQAl+H1d7gVecNdB5HL/YM90VhrCkP10fYBmef0cMO23jtPBYj2yRVDo6s4uuhg== X-Received: by 2002:a63:fd0b:0:b0:415:f76b:a2cd with SMTP id d11-20020a63fd0b000000b00415f76ba2cdmr816661pgh.440.1659602957225; Thu, 04 Aug 2022 01:49:17 -0700 (PDT) Received: from [192.168.255.10] ([103.7.29.32]) by smtp.gmail.com with ESMTPSA id z4-20020a170902ccc400b0016be9d498d0sm283814ple.211.2022.08.04.01.49.14 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 04 Aug 2022 01:49:16 -0700 (PDT) Message-ID: Date: Thu, 4 Aug 2022 16:49:08 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH v2 2/7] perf/x86/core: Remove unnecessary stubs provided for KVM-only helpers Content-Language: en-US To: Sean Christopherson Cc: Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Paolo Bonzini , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo References: <20220803192658.860033-1-seanjc@google.com> <20220803192658.860033-3-seanjc@google.com> From: Like Xu In-Reply-To: <20220803192658.860033-3-seanjc@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 4/8/2022 3:26 am, Sean Christopherson wrote: > Remove CONFIG_PERF_EVENT=n stubs for functions that are effectively > KVM-only. KVM selects PERF_EVENT and will never consume the stubs. > Dropping the unnecessary stubs will allow simplifying x86_perf_get_lbr() Giggling, I used to have a similar cleanup patch sitting in a corner somewhere. > by getting rid of the impossible-to-hit error path (which KVM doesn't > even check). > > Opportunstically reorganize the declarations to collapse multiple > CONFIG_PERF_EVENTS #ifdefs. > > Signed-off-by: Sean Christopherson > --- > arch/x86/include/asm/perf_event.h | 53 ++++++++----------------------- > 1 file changed, 13 insertions(+), 40 deletions(-) > > diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h > index cc47044401ff..aba196172500 100644 > --- a/arch/x86/include/asm/perf_event.h > +++ b/arch/x86/include/asm/perf_event.h > @@ -509,46 +509,18 @@ extern u64 perf_get_hw_event_config(int hw_event); > extern void perf_check_microcode(void); > extern void perf_clear_dirty_counters(void); > extern int x86_perf_rdpmc_index(struct perf_event *event); > -#else > -static inline void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap) > -{ > - memset(cap, 0, sizeof(*cap)); > -} > > -static inline u64 perf_get_hw_event_config(int hw_event) > -{ > - return 0; > -} > - > -static inline void perf_events_lapic_init(void) { } > -static inline void perf_check_microcode(void) { } > -#endif > - > -#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL) > +#ifdef CONFIG_CPU_SUP_INTEL > extern struct perf_guest_switch_msr *perf_guest_get_msrs(int *nr, void *data); > extern int x86_perf_get_lbr(struct x86_pmu_lbr *lbr); > -#else > -struct perf_guest_switch_msr *perf_guest_get_msrs(int *nr, void *data); > -static inline int x86_perf_get_lbr(struct x86_pmu_lbr *lbr) > -{ > - return -1; > -} > -#endif > +extern void intel_pt_handle_vmx(int on); > +#endif /* CONFIG_CPU_SUP_INTEL */ > > -#ifdef CONFIG_CPU_SUP_INTEL > - extern void intel_pt_handle_vmx(int on); > -#else > -static inline void intel_pt_handle_vmx(int on) > -{ > +#ifdef CONFIG_CPU_SUP_AMD > +extern void amd_pmu_enable_virt(void); > +extern void amd_pmu_disable_virt(void); > > -} > -#endif > - > -#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD) > - extern void amd_pmu_enable_virt(void); > - extern void amd_pmu_disable_virt(void); > - > -#if defined(CONFIG_PERF_EVENTS_AMD_BRS) > +#ifdef CONFIG_PERF_EVENTS_AMD_BRS > > #define PERF_NEEDS_LOPWR_CB 1 > > @@ -566,12 +538,13 @@ static inline void perf_lopwr_cb(bool lopwr_in) > static_call_mod(perf_lopwr_cb)(lopwr_in); > } > > -#endif /* PERF_NEEDS_LOPWR_CB */ Oops, now the definition of PERF_NEEDS_LOPWR_CB will not be unset. This is not mentioned in the commit message and may cause trouble. > +#endif /* CONFIG_PERF_EVENTS_AMD_BRS */ > +#endif /* CONFIG_CPU_SUP_AMD */ > > -#else > - static inline void amd_pmu_enable_virt(void) { } > - static inline void amd_pmu_disable_virt(void) { } > -#endif > +#else /* !CONFIG_PERF_EVENTS */ > +static inline void perf_events_lapic_init(void) { } > +static inline void perf_check_microcode(void) { } > +#endif /* CONFIG_PERF_EVENTS */ > > #define arch_perf_out_copy_user copy_from_user_nmi >