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Date:   Thu, 22 Aug 2019 10:11:53 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Atish Patra <atish.patra@wdc.com>
Cc:     linux-kernel@vger.kernel.org, Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv@lists.infradead.org,
        Palmer Dabbelt <palmer@sifive.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Christoph Hellwig <hch@lst.de>, Anup Patel <Anup.Patel@wdc.com>
Subject: Re: [PATCH v4 3/3] RISC-V: Issue a tlb page flush if possible
Message-ID: <20190822081153.GC17573@lst.de>
References: <20190822075151.24838-1-atish.patra@wdc.com> <20190822075151.24838-4-atish.patra@wdc.com>
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On Thu, Aug 22, 2019 at 12:51:51AM -0700, Atish Patra wrote:
> If tlbflush request is for page only, there is no need to do a
> complete local tlb shootdown.
> 
> Just do a local tlb flush for the given address.

Looks good, although I suspect in many cases even doing multiple
single-page sfence.vma calls might be cheaper than the global one.

But I think that is worth a ѕeparate discussion, preferably with actual
numbers.

Reviewed-by: Christoph Hellwig <hch@lst.de>