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From: Stefan Roscher <ossrosch@linux.vnet.ibm.com>
To: michael <michael@evidence.eu.com>
Subject: Re: [PATCH 1/3] IB/ehca: Replace vmalloc with kmalloc
Date: Wed, 22 Apr 2009 18:00:41 +0200
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Cc: Roland Dreier <rdreier@cisco.com>, fenkes@de.ibm.com,
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On Wednesday 22 April 2009 04:10:18 pm michael wrote:
> Hi,
> 

> I don't take the point, if it is not import use the vmalloc. Why you try 
> with a kmalloc
> alloc first? and why do not use kzalloc?

Because kmalloc() is faster than vmalloc() causing a huge performance win
when someone allocates a large number of queue pairs. We fall back to
vmalloc() only if kmalloc() can't deliver the memory chunk.
We don't need kzalloc because we fill the list right after the alloc.

regards Stefan