From: Jaco Kroon <jaco@kroon.co.za>
Date: Mon, 16 Apr 2007 14:12:34 +0000
Subject: [KJ] possible power of two cleanup?
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To: kernel-janitors@vger.kernel.org

Hi guys,

Just stumbled upon this in include/linux/blockgroup_lock.h

It looks like it essentially does a round up to the nearest power of two 
of NR_CPUS * 4?  Is this a potential cleanup?  Prevent breakage when we 
start having more than 64 CPUs in a machine?

/*
  * We want a power-of-two.  Is there a better way than this?
  */

#if NR_CPUS >= 32
#define NR_BG_LOCKS 128
#elif NR_CPUS >= 16
#define NR_BG_LOCKS 64
#elif NR_CPUS >= 8
#define NR_BG_LOCKS 32
#elif NR_CPUS >= 4
#define NR_BG_LOCKS 16
#elif NR_CPUS >= 2
#define NR_BG_LOCKS 8
#else
#define NR_BG_LOCKS 4
#endif

Jaco
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