From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Date: Tue, 20 Oct 2009 07:12:13 +0000
Subject: Re: Commit 34d76c41 causes linker errors on ia64 with NR_CPUS=4096
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To: Ingo Molnar <mingo@elte.hu>
Cc: Jiri Kosina <jkosina@suse.cz>, Jeff Mahoney <jeffm@suse.com>, Peter Zijlstra <peterz@infradead.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Tony Luck <tony.luck@intel.com>, Fenghua Yu <fenghua.yu@intel.com>, linux-ia64@vger.kernel.org

Hello,

Ingo Molnar wrote:
> Still looks like a bug if it causes a breakage (linker error) on IA64, 

In a sense, yes.

> and if the 'fix' (i'd call it a workaround) causes a (small but nonzero) 
> performance regression on other architectures.

Yeah, by small amount but also reduces memory usage quite a bit.  For
this case, I think dynamic allocation is actually the right thing to
do.

Extending the first chunk size shouldn't be difficult on ia64 but
other than this, there still is a lot of room left with the current
64k limit, so I think we should be safe for a while.  BTW, I also am
curious how lockdep has been coping with the limit.

Thanks.

-- 
tejun