From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH] NUMA aware allocation of transmit and receive buffers
 for e1000
Date: Wed, 18 May 2005 13:42:50 -0700
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To: Ganesh Venkatesan <ganesh.venkatesan@gmail.com>
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Ganesh Venkatesan <ganesh.venkatesan@gmail.com> wrote:
>
> On 5/17/05, Andrew Morton <akpm@osdl.org> wrote:
> > I think the e1000 driver is being a bit insane there.  I figure that
> Do you mean insane to use vmalloc?
> 
> > sizeof(struct e1000_buffer) is 28 on 64-bit, so even with 4k pagesize we'll
> > always succeed in being able to support a 32k/32 = 1024-entry Tx ring.
> > 
> > Is there any real-world reason for wanting larger ring sizes than that?
> > 
> > 
> We have had cases where allocation of 32K of memory (via kmalloc) fails. 
> 

Are you sure?  The current page allocator will infinitely loop until
success for <=32k GFP_KERNEL allocations - the only way it can fail is if
the calling process gets oom-killed.