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Date:   Mon, 21 Jan 2019 21:51:47 +0000
From:   Christopher Lameter <cl@linux.com>
To:     Davidlohr Bueso <dave@stgolabs.net>
cc:     akpm@linux-foundation.org, dledford@redhat.com, jgg@mellanox.com,
        jack@suse.de, ira.weiny@intel.com, linux-rdma@vger.kernel.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Davidlohr Bueso <dbueso@suse.de>
Subject: Re: [PATCH 1/6] mm: make mm->pinned_vm an atomic64 counter
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References: <20190121174220.10583-1-dave@stgolabs.net> <20190121174220.10583-2-dave@stgolabs.net>
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On Mon, 21 Jan 2019, Davidlohr Bueso wrote
> Taking a sleeping lock to _only_ increment a variable is quite the
> overkill, and pretty much all users do this. Furthermore, some drivers
> (ie: infiniband and scif) that need pinned semantics can go to quite
> some trouble to actually delay via workqueue (un)accounting for pinned
> pages when not possible to acquire it.

Reviewed-by: Christoph Lameter <cl@linux.com>