Message-ID: <4889205C.9080806@sgi.com>
Date: Thu, 24 Jul 2008 17:37:48 -0700
From: Mike Travis <travis@sgi.com>
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To: Rusty Russell <rusty@rustcorp.com.au>
CC: Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>,
       "H. Peter Anvin" <hpa@zytor.com>, Jack Steiner <steiner@sgi.com>,
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Subject: Re: [PATCH 1/1] cpumask: Change cpumask_of_cpu to use cpumask_of_cpu_map
References: <20080723171841.815234000@polaris-admin.engr.sgi.com> <20080723171841.997896000@polaris-admin.engr.sgi.com> <200807241245.17239.rusty@rustcorp.com.au> <4888C232.4090906@sgi.com>
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Mike Travis wrote:
> Rusty Russell wrote:
>> On Thursday 24 July 2008 03:18:42 Mike Travis wrote:
>>>     Note that the declaration of cpumask_of_cpu_map[] is initialized
>>>     so that cpumask_of_cpu(0) is defined early.  This assumes that
>>>     cpu 0 is the boot cpu.
>> Hi Mike,
>>
>>    Make this statically initialized please.  That almost guarantees there'll
>> be no problems.  It's a little tricky to do, but possible.  Patch below
>> tested on 32 bit x86 only.
> 
> I thought about it, but it didn't seem to be worth the effort.  One problem
> though, the cpumask bits are such that the LSB of the last word is cpu 0.
> So your initializer sets it up in reverse order.  I'll see if I can't
> figure out how to invert it (very tricky coding btw... ;-)

I thought since the cpumask_scnprintf prints out the bit map with the LSB
being cpu 0 that the bit layout was the same.  Further examination reveals
I was wrong about that.

The updated patchset to follow shortly after a bit more testing...

Thanks,
Mike
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