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Date:   Tue, 19 May 2020 05:54:15 -0700
From:   Michel Lespinasse <walken@google.com>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-mm <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Laurent Dufour <ldufour@linux.ibm.com>,
        Matthew Wilcox <willy@infradead.org>,
        Liam Howlett <Liam.Howlett@oracle.com>,
        Jerome Glisse <jglisse@redhat.com>,
        Davidlohr Bueso <dave@stgolabs.net>,
        David Rientjes <rientjes@google.com>,
        Hugh Dickins <hughd@google.com>, Ying Han <yinghan@google.com>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Daniel Jordan <daniel.m.jordan@oracle.com>
Subject: Re: [PATCH v5 06/10] mmap locking API: convert nested write lock
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On Mon, May 18, 2020 at 12:32:03PM +0200, Vlastimil Babka wrote:
> On 4/22/20 2:14 AM, Michel Lespinasse wrote:
> > Add API for nested write locks and convert the few call sites doing that.
> > 
> > Signed-off-by: Michel Lespinasse <walken@google.com>
> > Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
> 
> Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
> 
> Perhaps we could even move SINGLE_DEPTH_NESTING into the wrapper? It's unlikely
> there will be a new user with a different subclass?

I think I'll leave it in the API for now. I don't foresee new uses
being added as long as we stick to coarse mmap locking, but if
extending the api to support range locking it'd become more likely
that we'd want to lock multiple ranges for mremap...

-- 
Michel "Walken" Lespinasse
A program is never fully debugged until the last user dies.