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Date: Fri, 1 Jul 2016 08:55:42 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "T.Zhou" <t1zhou@163.com>
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched: Assign !p->on_cpu to the second parameter of
 smp_cond_load_acquire()
Message-ID: <20160701065542.GJ30921@twins.programming.kicks-ass.net>
References: <20160701030801.GA15593@root>
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On Fri, Jul 01, 2016 at 11:08:01AM +0800, T.Zhou wrote:

> -	smp_cond_load_acquire(&p->on_cpu, !VAL);
> +	smp_cond_load_acquire(&p->on_cpu, !p->on_cpu);

Huh, what?! No, the second parameter should very much include VAL, which
gets assigned the value of *(&p->on_cpu).

Go read the macro, it even has a comment on.