From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hideo AOKI <haoki@redhat.com>
Subject: Re: [PATCH 2/5] accounting unit and variable
Date: Tue, 13 Nov 2007 22:27:13 -0500
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References: <47264E2D.4080109@redhat.com> <47264F3E.3080306@redhat.com> <20071109123420.GD27984@gondor.apana.org.au>
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Cc: David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	Satoshi Oshima <satoshi.oshima.fk@hitachi.com>,
	Andi Kleen <andi@firstfloor.org>,
	Stephen Hemminger <shemminger@linux-foundation.org>,
	Evgeniy Polyakov <johnpol@2ka.mipt.ru>,
	yoshfuji@linux-ipv6.org,
	Yumiko Sugita <yumiko.sugita.yf@hitachi.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
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Hello,

Herbert Xu wrote:
> On Mon, Oct 29, 2007 at 05:23:10PM -0400, Hideo AOKI wrote:
>>  
>> +#define SK_DATAGRAM_MEM_QUANTUM ((int)PAGE_SIZE)
>> +
>> +static inline int sk_datagram_pages(int amt)
>> +{
>> +	return DIV_ROUND_UP(amt, SK_DATAGRAM_MEM_QUANTUM);
>> +}
> 
> Does this really have to be int? Unsigned would let the compiler
> optimise this to a simple shift.

Thank you for the comment.

This inline function is used to calculate the first argument of atomic_add()
and atomic_sub(). Since the argument is int, I believe that using int is
better than using unsigned int.

Best regards,
Hideo

--
Hitachi Computer Products (America) Inc.