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Date:   Fri, 2 Sep 2022 11:39:34 +0800
From:   Baoquan He <bhe@redhat.com>
To:     Uladzislau Rezki <urezki@gmail.com>
Cc:     Song Liu <song@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux-MM <linux-mm@kvack.org>,
        open list <linux-kernel@vger.kernel.org>,
        Song Liu <songliubraving@fb.com>
Subject: Re: [PATCH] mm/vmalloc: Extend find_vmap_lowest_match_check with
 extra arguments
Message-ID: <YxF69izHufARLKqA@MiWiFi-R3L-srv>
References: <20220831052734.3423079-1-song@kernel.org>
 <20220831160111.a6e7d17785ca21ce7c43981c@linux-foundation.org>
 <CAPhsuW4SGguyoFKpN8S=jFCWfLiDM-f5QwV7UPwkQ=LjQEXaNg@mail.gmail.com>
 <CA+KHdyUDGkUBtnAcvu+NB=S7chp_1N3XviTkkMoP-8LrLJQgbg@mail.gmail.com>
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On 09/01/22 at 02:16pm, Uladzislau Rezki wrote:
> This is only for debug purpose.
> 
> Even without this patch, the debug path would work correctly. The
> difference is just only in
> whether roots are hardcoded or passed over function paramter.

Calling find_vmap_lowest_match() inside find_vmap_lowest_match_check()
will fail compilation because the function interface has been changed.

> 
> On Thu, Sep 1, 2022 at 2:47 AM Song Liu <song@kernel.org> wrote:
> >
> > On Wed, Aug 31, 2022 at 4:01 PM Andrew Morton <akpm@linux-foundation.org> wrote:
> > >
> > > On Tue, 30 Aug 2022 22:27:34 -0700 Song Liu <song@kernel.org> wrote:
> > >
> > > > find_vmap_lowest_match() is now able to handle different roots. Make
> > > > similar changes to find_vmap_lowest_match_check() and
> > > > find_vmap_lowest_linear_match() to handle different trees.
> > >
> > > What are the runtime effects of this change?
> >
> > The code is gated by DEBUG_AUGMENT_LOWEST_MATCH_CHECK. It
> > is only compiled when the developer enables it explicitly. Therefore,
> > there isn't
> > any runtime effect.
> >
> > Thanks,
> > Song
> 
> 
> 
> -- 
> Uladzislau Rezki
>