Date: Mon, 30 Oct 2006 12:42:30 -0800 (PST)
From: Zwane Mwaikambo <zwane@infradead.org>
Subject: Re: [PATCH] vmalloc : optimization, cleanup, bugfixes
In-reply-to: <453C87A6.4060602@yahoo.com.au>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Eric Dumazet <dada1@cosmosbay.com>, Andrew Morton <akpm@osdl.org>,
       linux-kernel@vger.kernel.org
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On Mon, 23 Oct 2006, Nick Piggin wrote:

> Eric Dumazet wrote:
> > [PATCH] vmalloc : optimization, cleanup, bugfixes
> > 
> > This patch does three things
> > 
> > 1) reorder 'struct vm_struct' to speedup lookups on CPUS with small cache
> > lines. The fields 'next,addr,size' should be now in the same cache line, to
> > speedup lookups.
> > 
> > 2) One minor cleanup in __get_vm_area_node()
> > 
> > 3) Bugfixes in vmalloc_user() and vmalloc_32_user()
> > NULL returns from __vmalloc() and __find_vm_area() were not tested.
> 
> Hmm, so they weren't. As far as testing the return of __find_vm_area,
> you can just turn that into a BUG_ON(!area), because at that point,
> we've established that the vmalloc succeeded.

No need for a BUG_ON it'll simply be a NULL dereference, at which point 
we're back to the original code.

	Zwane

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