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Date: Thu, 20 Aug 2015 20:29:03 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Kevin Hao <haokexin@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@lists.ozlabs.org,
 linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
 Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH 1/8] jump_label: no need to acquire the jump_label_mutex
 in jump_lable_init()
Message-ID: <20150820182903.GA3161@worktop.event.rightround.com>
References: <1440072876-8321-1-git-send-email-haokexin@gmail.com>
 <1440072876-8321-2-git-send-email-haokexin@gmail.com>
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On Thu, Aug 20, 2015 at 08:14:29PM +0800, Kevin Hao wrote:
> The jump_label_init() run in a very early stage, even before the
> sched_init(). So there is no chance for concurrent access of the
> jump label table.

It also doesn't hurt to have it. Its better to be consistent and
conservative with locking unless there is a pressing need.