Re: [PATCH 4/4] ARM: mmp: add SMP support for pxa988

From: Haojian Zhuang
Date: Fri Apr 19 2013 - 11:42:58 EST


On Fri, Apr 19, 2013 at 10:09 PM, Russell King - ARM Linux
<linux@xxxxxxxxxxxxxxxx> wrote:
> On Sat, Apr 13, 2013 at 09:08:12PM +0800, Haojian Zhuang wrote:
>> On Thu, Apr 11, 2013 at 11:39 AM, Neil Zhang <zhangwm@xxxxxxxxxxx> wrote:
>> > + /*
>> > + * Synchronise with the boot thread.
>> > + */
>> > + spin_lock(&boot_lock);
>> > + spin_unlock(&boot_lock);
>> Lock & unlock without protecting anything. If so, you can remove this.
>
> ... which means you don't understand what is going on in this code,
> and probably didn't read the comment above this fragment. The above
> is to synchronise with the code below - again, read the comment at
> the spin unlock in this function, remembering that the above code
> and the code below runs concurrently on two different CPUs:
>
Yes, I misunderstood it. Thanks for your correction.

Regards
Haojian
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