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From:   Muchun Song <songmuchun@bytedance.com>
Date:   Tue, 5 Jul 2022 17:12:14 +0800
Message-ID: <CAMZfGtVQnxEr1gqfMgU1YzFsPXA08aOnR-mu-8cKnuS=LUyLKg@mail.gmail.com>
Subject: Re: [PATCH V4 4/4] LoongArch: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Huacai Chen <chenhuacai@kernel.org>,
        Huacai Chen <chenhuacai@loongson.cn>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, loongarch@lists.linux.dev,
        linux-arch <linux-arch@vger.kernel.org>,
        Xuefeng Li <lixuefeng@loongson.cn>,
        Guo Ren <guoren@kernel.org>, Xuerui Wang <kernel@xen0n.name>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux-MM <linux-mm@kvack.org>,
        "open list:BROADCOM NVRAM DRIVER" <linux-mips@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Feiyang Chen <chenfeiyang@loongson.cn>
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On Tue, Jul 5, 2022 at 4:46 PM Arnd Bergmann <arnd@arndb.de> wrote:
>
> On Tue, Jul 5, 2022 at 10:38 AM Muchun Song <songmuchun@bytedance.com> wrote:
> > On Tue, Jul 5, 2022 at 4:06 PM Arnd Bergmann <arnd@arndb.de> wrote:
> > > On Tue, Jul 5, 2022 at 9:51 AM Muchun Song <songmuchun@bytedance.com> wrote:
> >
> > How about including the static key header in the scope of
> > CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP?
>
> That helps a little, but it means we still pay for it on x86 and
> arm64, which are the
> most common architectures.

Alright. Make sense.

>
>        Arnd