From: Arnd Bergmann <arnd@arndb.de>
To: "Guan Xuetao" <gxt@mprc.pku.edu.cn>
Subject: Re: [PATCH] unicore32 framebuffer driver fix: make videomemory kmalloc-ed and floatable
Date: Wed, 30 Mar 2011 08:54:05 +0200
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Cc: "'Paul Mundt'" <lethal@linux-sh.org>, linux-kernel@vger.kernel.org,
        linux-fbdev@vger.kernel.org
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On Wednesday 30 March 2011 03:39:26 Guan Xuetao wrote:
> > How does this work? UNIFB_MEMSIZE seems to be 4 MB, much more than the
> > maximum of 128 KB that kmalloc can allocate.
> > 
> > Shouldn't this use get_free_pages() instead of kmalloc?
> > 
> 
> When using SLUB allocator, if required memory size  is larger
> than 2*PAGE_SIZE, kmalloc_large is called,
> and eventually __get_free_pages will  be called.
> So,  it would be the same as __get_free_pages.

Ok, I see. It's probably still better to use __get_free_pages directly,
because it's possible to select a different allocator that does not
do this itself.

	Arnd
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