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Date:   Tue, 4 Dec 2018 14:49:42 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Josef Bacik <josef@toxicpanda.com>
Cc:     kernel-team@fb.com, hannes@cmpxchg.org,
        linux-kernel@vger.kernel.org, tj@kernel.org, david@fromorbit.com,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, riel@redhat.com,
        jack@suse.cz
Subject: Re: [PATCH 1/4] mm: infrastructure for page fault page caching
Message-Id: <20181204144942.63c98a3147071f054d77427d@linux-foundation.org>
In-Reply-To: <20181130195812.19536-2-josef@toxicpanda.com>
References: <20181130195812.19536-1-josef@toxicpanda.com>
        <20181130195812.19536-2-josef@toxicpanda.com>
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On Fri, 30 Nov 2018 14:58:09 -0500 Josef Bacik <josef@toxicpanda.com> wrote:

> We want to be able to cache the result of a previous loop of a page
> fault in the case that we use VM_FAULT_RETRY,

Please explain here why we want to do that.

> so introduce
> handle_mm_fault_cacheable that will take a struct vm_fault directly, add
> a ->cached_page field to vm_fault, and add helpers to init/cleanup the
> struct vm_fault.
> 
> I've converted x86, other arch's can follow suit if they so wish, it's
> relatively straightforward.
>