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From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
To: Paul Mackerras <paulus@samba.org>
Subject: Re: [PATCH -V3 10/11] arch/powerpc: Use 32bit array for slb cache
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Date: Mon, 23 Jul 2012 13:55:31 +0530
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Paul Mackerras <paulus@samba.org> writes:

> On Mon, Jul 09, 2012 at 06:43:40PM +0530, Aneesh Kumar K.V wrote:
>> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
>> 
>> With larger vsid we need to track more bits of ESID in slb cache
>> for slb invalidate.
>> 
>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
>
> Minor comment below, but apart from that...
>
> Reviewed-by: Paul Mackerras <paulus@samba.org>
>
>> -	sldi	r11,r3,1		/* r11 = offset * sizeof(u16) */
>> -	rldicl	r10,r10,36,28		/* get low 16 bits of the ESID */
>> -	add	r11,r11,r13		/* r11 = (u16 *)paca + offset */
>> -	sth	r10,PACASLBCACHE(r11)	/* paca->slb_cache[offset] = esid */
>> +	sldi	r11,r3,2		/* r11 = offset * sizeof(u32) */
>> +	rldicl	r10,r10,36,28		/* get the 36 bits of the ESID */
>
> You're correct that the rldicl instruction produces 36 bits of result,
> and in fact it is equivalent to srdi r10,r10,28.  If you're changing
> the line you might as well change the instruction to the simpler form
> too.

done.

-aneesh