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Date: Sun, 1 May 2016 10:01:20 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Muhammad Falak R Wani <falakreyaz@gmail.com>, paulmck@linux.vnet.ibm.com
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>,
        target-devel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] target: use RCU_INIT_POINTER() when NULLing.
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On Sun, May 01, 2016 at 06:22:01PM +0530, Muhammad Falak R Wani wrote:
> It is safe to use RCU_INIT_POINTER() to NULL, instead of
> rcu_assign_pointer().
> This results in slightly smaller/faster code.

If this is indeed the case, rcu_assign_pointer should simply check
for NULL using __builtin_constant_p and do the right thing transparently
instead of burdening it on every user.