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Date: Fri, 21 Dec 2012 22:44:31 -0500
From: Rik van Riel <riel@redhat.com>
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To: Eric Dumazet <eric.dumazet@gmail.com>
CC: linux-kernel@vger.kernel.org, aquini@redhat.com, walken@google.com,
        lwoodman@redhat.com, jeremy@goop.org,
        Jan Beulich <JBeulich@novell.com>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [RFC PATCH 3/3 -v2] x86,smp: auto tune spinlock backoff delay
 factor
References: <20121221184940.103c31ad@annuminas.surriel.com>  <20121221185147.4ae48ab5@annuminas.surriel.com>  <20121221185613.1f4c9523@annuminas.surriel.com> <1356146982.21834.8321.camel@edumazet-glaptop>
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On 12/21/2012 10:29 PM, Eric Dumazet wrote:
> On Fri, 2012-12-21 at 18:56 -0500, Rik van Riel wrote:
>> +	int *delay_ptr = &per_cpu(spinlock_delay, smp_processor_id());
>> +	int delay = *delay_ptr;
>
> int delay = __this_cpu_read(spinlock_delay);
>
>>   	}
>> +	*delay_ptr = delay;
>
> __this_cpu_write(spinlock_delay, delay);

Thanks for that cleanup. I have applied it to my code.