Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 18 Jan 2022 13:27:37 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Charan Teja Kalla <quic_charante@quicinc.com>
Cc:     Mark Hemment <markhemm@googlemail.com>, hughd@google.com,
        Andrew Morton <akpm@linux-foundation.org>, vbabka@suse.cz,
        rientjes@google.com, mhocko@suse.com, surenb@google.com,
        shakeelb@google.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Charan Teja Reddy <charante@codeaurora.org>
Subject: Re: [PATCH v3 RESEND] mm: shmem: implement
 POSIX_FADV_[WILL|DONT]NEED for shmem
Message-ID: <YebASTShsELnoiVj@casper.infradead.org>
References: <1641488717-13865-1-git-send-email-quic_charante@quicinc.com>
 <CANe_+UipVZRZeWqzXezacPaVb9UeC6a_ZhQp8GkrvftbRktotg@mail.gmail.com>
 <2c66ba2e-1c65-3bdd-b91e-eb8391ec6dbf@quicinc.com>
 <61212ffd-3505-04d7-5403-932a10d676e7@quicinc.com>
 <Yd7VZId4IlKd4VpC@casper.infradead.org>
 <eb056201-a6e2-a58e-dd77-666f124d1896@quicinc.com>
 <a31bdd1a-0fd8-7303-dc97-a2cf156f1d83@quicinc.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <a31bdd1a-0fd8-7303-dc97-a2cf156f1d83@quicinc.com>
Precedence: bulk

On Tue, Jan 18, 2022 at 05:05:40PM +0530, Charan Teja Kalla wrote:
> Hello Matthew,
> 
> > Yes.  This should obviously be an xa_for_each() loop.
> 
> In one of your patch[1], where we used xarray iterator, though most of
> the entries found requires to call xas_pause() but still endup in using
> xas_for_each() rather than xa_for_each(). Then, Should this code be
> changed to use xa_for_each()? The documentation also says that "The
> xas_for_each() iterator will expand into more inline code than
> xa_for_each()."
> 
> [1]https://patchwork.kernel.org/project/linux-mm/patch/20200819184850.24779-4-willy@infradead.org/

How do you know the distribution of swap and non-swap entries in that
region of that xarray?