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Date:   Wed, 15 Nov 2023 13:37:43 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Ryan Roberts <ryan.roberts@arm.com>
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Ard Biesheuvel <ardb@kernel.org>,
        Marc Zyngier <maz@kernel.org>,
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        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Zenghui Yu <yuzenghui@huawei.com>,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        Alexander Potapenko <glider@google.com>,
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        Dmitry Vyukov <dvyukov@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Matthew Wilcox <willy@infradead.org>,
        Yu Zhao <yuzhao@google.com>,
        Mark Rutland <mark.rutland@arm.com>,
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        Kefeng Wang <wangkefeng.wang@huawei.com>,
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        linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 01/14] mm: Batch-copy PTE ranges during fork()
Message-Id: <20231115133743.674690dc78041768b79fadd9@linux-foundation.org>
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On Wed, 15 Nov 2023 16:30:05 +0000 Ryan Roberts <ryan.roberts@arm.com> wrote:

> However, the primary motivation for this change is to reduce the number
> of tlb maintenance operations that the arm64 backend has to perform
> during fork

Do you have a feeling for how much performance improved due to this? 

Are there other architectures which might similarly benefit?  By
implementing ptep_set_wrprotects(), it appears.  If so, what sort of
gains might they see?