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Date: Mon, 22 Sep 2008 08:44:53 -0700
From: Mike Travis <travis@sgi.com>
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To: Ingo Molnar <mingo@elte.hu>
CC: Rusty Russell <rusty@rustcorp.com.au>, Dean Nelson <dcn@sgi.com>,
       "Eric W. Biederman" <ebiederm@xmission.com>,
       "H. Peter Anvin" <hpa@zytor.com>, Jack Steiner <steiner@sgi.com>,
       Alan Mayer <ajm@sgi.com>, jeremy@goop.org, suresh.b.siddha@intel.com,
       torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
       Thomas Gleixner <tglx@linutronix.de>, Yinghai Lu <Yinghai.lu@amd.com>
Subject: Re: [PATCH 1/3] switch vector_irq[] from irq number to irq_desc	pointer
 v2
References: <20080919200212.GA6528@sgi.com> <20080919200449.GB6528@sgi.com> <48D40A97.2000402@sgi.com> <20080922110542.GD5987@elte.hu> <48D7B5F8.9020300@sgi.com>
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Mike Travis wrote:
> Ingo Molnar wrote:
>> * Mike Travis <travis@sgi.com> wrote:
>>
>>> Hi Ingo,
>>>
>>> Note that my recent patch from a couple of weeks ago, stripped almost 
>>> all of the cpumask_t's from the io_apic functions.  Any chance we can 
>>> apply them before we add more?
>>>
>>> I'd be willing to merge in Dean's patch over the top of mine (or 
>>> vice-versa).
>> i'm really looking forwards to Rusty's 'get-rid-of-cpumask_t use' 
>> patchset, which would solve such cpumask_t proliferation issues once and 
>> for all.
>>
>> 	Ingo
> 
> Hi Ingo,
> 
> The net effect of the "getting rid of cpumask_t's" will be the same.  This
> patch reduces considerably the amount of stack space being required right
> now.  

Btw, my patch will still be useful even after cpumask's are passed by reference
in that it optimizes the cpumask's that are being used.  For example, in one
function 3 cpumask_t's become 1.  In some others, 2 were reduced to 1.  Since
the new cpumask approach will require temp cpumask's, this cuts down on the
number of temp cpumask's required.

Thanks,
Mike