Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751883AbbHRJ03 (ORCPT ); Tue, 18 Aug 2015 05:26:29 -0400 Received: from mail-oi0-f43.google.com ([209.85.218.43]:34557 "EHLO mail-oi0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750770AbbHRJ01 (ORCPT ); Tue, 18 Aug 2015 05:26:27 -0400 MIME-Version: 1.0 In-Reply-To: <20150818083127.GB10301@arm.com> References: <=fu.wei@linaro.org> <1439555753-11974-1-git-send-email-fu.wei@linaro.org> <20150817100109.GE1688@arm.com> <55D26BF1.5090203@codeaurora.org> <20150818083127.GB10301@arm.com> Date: Tue, 18 Aug 2015 17:26:26 +0800 Message-ID: Subject: Re: [PATCH] acpi, apei, arm64: APEI initial support for aarch64. From: Fu Wei To: Will Deacon Cc: "Zhang, Jonathan Zhixiong" , "harba@codeaurora.org" , "linaro-acpi@lists.linaro.org" , "linux-kernel@vger.kernel.org" , "matt.fleming@intel.com" , "tekkamanninja@gmail.com" , "graeme.gregory@linaro.org" , "al.stone@linaro.org" , "hanjun.guo@linaro.org" , "jcm@redhat.com" , Mark Rutland , Catalin Marinas , "rjw@rjwysocki.net" , "bp@alien8.de" , Tomasz Nowicki Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3482 Lines: 94 Hi On 18 August 2015 at 16:31, Will Deacon wrote: > On Tue, Aug 18, 2015 at 12:19:13AM +0100, Zhang, Jonathan Zhixiong wrote: >> On 8/17/2015 3:01 AM, Will Deacon wrote: >> > On Fri, Aug 14, 2015 at 01:35:53PM +0100, fu.wei@linaro.org wrote: >> >> diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h >> >> index a17b623..ced6e25 100644 >> >> --- a/arch/arm64/include/asm/acpi.h >> >> +++ b/arch/arm64/include/asm/acpi.h >> >> @@ -22,6 +22,7 @@ >> >> #ifdef CONFIG_ACPI_APEI >> >> #include >> >> #include >> >> +#include >> >> #endif >> >> >> >> /* Macros for consistency checks of the GICC subtable of MADT */ >> >> @@ -52,6 +53,9 @@ typedef u64 phys_cpuid_t; >> >> extern int acpi_disabled; >> >> extern int acpi_noirq; >> >> extern int acpi_pci_disabled; >> >> +#ifdef CONFIG_ACPI_APEI >> >> +extern int acpi_disable_cmcff; >> >> +#endif >> >> >> >> static inline void disable_acpi(void) >> >> { >> >> @@ -89,6 +93,13 @@ static inline bool acpi_has_cpu_in_madt(void) >> >> static inline void arch_fix_phys_package_id(int num, u32 slot) { } >> >> void __init acpi_init_cpus(void); >> >> >> >> +#ifdef CONFIG_ACPI_APEI >> >> +static inline void arch_apei_flush_tlb_one(unsigned long addr) >> >> +{ >> >> + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); >> >> +} >> >> +#endif >> > >> > Looking at the callers of this function, I suspect we could downgrade it >> > to a local CPU invalidation if we wanted. However, this isn't a hot-path >> > so it's fine to stay like it is for now. >> I suppose if we run "tlbi vae1" instead of "tlbi vae1is", it will be >> more efficient without side effect, since both ghes_ioremap_pfn_irq() >> and ghes_iounmap_irq() happen in same atomic context. However, today >> arch/arm64/include/asm/tlbflush.h does not have a function tailored for >> such performance optimization. Does it make sense to add a parameter to >> flush_tlb_kernel_range() to allow caller to make a choice? >> static inline void flush_tlb_kernel_range(unsigned long start, >> unsigned long end, bool local) >> There are only two others callers of flush_tlb_kernel_range(). > > I've already got some patches to add things like local_flush_tlb_all, > which I'll post after the merge window (I'm currently rewriting a bunch > of the switch_mm code to try to reduce the TLBI traffic). If I understand correctly, these patches add new functions, instead of changing the existent one. I thinks this way is better. If we have new patch for optimizing TLB flushing, we can make a new patchset for this in the future. Because this patch is only for enabling APEI on aarch64. > > If this isn't a hotpath (I don't think it is), then it's probably not > worth making the optimisation without a system to benchmark it on. agree. But please let me know if you have any suggestion on this patch. is this patch OK for you? > > Will -- Best regards, Fu Wei Software Engineer Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch Ph: +86 21 61221326(direct) Ph: +86 186 2020 4684 (mobile) Room 1512, Regus One Corporate Avenue,Level 15, One Corporate Avenue,222 Hubin Road,Huangpu District, Shanghai,China 200021 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/