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Date: Mon, 14 Apr 2003 14:58:52 -0700
From: Andrew Morton <akpm@digeo.com>
To: Andi Kleen <ak@suse.de>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] blockgroup_lock: hashed spinlocks for ext2 and ext3
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Andi Kleen <ak@suse.de> wrote:
>
> > 
> > And this hashed lock is not a per-cpu thing.  (No locks are!) It just uses
> > NR_CPUS to decide how big the hash should be.
> 
> Isn't that what the IBM kmalloc_per_cpu() was for ? (I think the patch
> was from Dipankar) 

This is not a per-cpu data structure.

It is a hashed spinlock which uses NR_CPUS as a sizing hint.