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Date:   Mon, 27 Sep 2021 12:11:43 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Nadav Amit <nadav.amit@gmail.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Peter Xu <peterx@redhat.com>,
        Nadav Amit <namit@vmware.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Minchan Kim <minchan@kernel.org>,
        Colin Cross <ccross@google.com>,
        Suren Baghdasarya <surenb@google.com>,
        Mike Rapoport <rppt@linux.vnet.ibm.com>
Subject: Re: [RFC PATCH 2/8] mm/madvise: remove unnecessary check on
 madvise_dontneed_free()
Message-ID: <20210927091143.tn6ediykqycu6rtu@box.shutemov.name>
References: <20210926161259.238054-1-namit@vmware.com>
 <20210926161259.238054-3-namit@vmware.com>
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On Sun, Sep 26, 2021 at 09:12:53AM -0700, Nadav Amit wrote:
> From: Nadav Amit <namit@vmware.com>
> 
> madvise_dontneed_free() is called only from madvise_vma() and the
> behavior is always either MADV_FREE or MADV_DONTNEED. There is no need
> to check again in madvise_dontneed_free() if the behavior is any
> different.

So what. The check is free. Compiler should be clever enough to eliminate
the additional check. If there's a new MADV_DONTNEED flavour, the change
would have to be effectively reverted.

NAK.

-- 
 Kirill A. Shutemov