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Date: Tue, 18 Jun 2013 19:28:05 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Kirill Tkhai <tkhai@yandex.ru>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>, Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH 1/2] sched: Add schedule_(raw_)spin_unlock and
 schedule_(raw_)spin_unlock_irq
Message-ID: <20130618172805.GC16094@twins.programming.kicks-ass.net>
References: <1981131371569812@web20h.yandex.ru>
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On Tue, Jun 18, 2013 at 07:36:52PM +0400, Kirill Tkhai wrote:
> Helpers for replacement repeating patterns:
> 
> 1)spin_unlock(lock);
>   schedule();
> 2)spin_unlock_irq(lock);
>   schedule();
> 

I just noticed this; the existing schedule_preempt_disabled() is
equivalent to:

  preempt_enable()
  schedule()
  preempt_disable()

So I somewhat expected these new primitives to be:

  spin_unlock()
  schedule()
  spin_lock()

Now I haven't actually looked at the usage patch to see what the
converted sites look like (thanks for adding that one though!).

My OCD just triggered on the preemption and locked schedule calls having
different semantics.