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Date: Mon, 11 Feb 2013 01:00:02 +0530
From: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
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To: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH v5 05/45] percpu_rwlock: Make percpu-rwlocks IRQ-safe,
 optimally
References: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com>
 <20130122073400.13822.52336.stgit@srivatsabhat.in.ibm.com>
 <20130210184209.GA3041@redhat.com>
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On 02/11/2013 12:12 AM, Oleg Nesterov wrote:
> only one cosmetic nit...
> 
> On 01/22, Srivatsa S. Bhat wrote:
>>
>> +#define READER_PRESENT		(1UL << 16)
>> +#define READER_REFCNT_MASK	(READER_PRESENT - 1)
>> +
>>  #define reader_uses_percpu_refcnt(pcpu_rwlock, cpu)			\
>>  		(ACCESS_ONCE(per_cpu(*((pcpu_rwlock)->reader_refcnt), cpu)))
>>
>>  #define reader_nested_percpu(pcpu_rwlock)				\
>> -			(__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) > 1)
>> +	(__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) & READER_REFCNT_MASK)
>>
>>  #define writer_active(pcpu_rwlock)					\
>>  			(__this_cpu_read(*((pcpu_rwlock)->writer_signal)))
> 
> I think this all can go to lib/percpu-rwlock.c. Nobody needs to know
> these implementation details.
> 

Ok, will move them.
 
Regards,
Srivatsa S. Bhat