Re: [PATCH 2/3] mips:powertv: Make kernel command line size configurable (resend)

[David VomLehn <dvomlehn@cisco.com>]

On Wed, May 06, 2009 at 02:27:36PM -0400, Jon Fraser wrote:
> 
> 
> On Wed, 2009-05-06 at 11:24 -0700, David Daney wrote:
> > David VomLehn wrote:
> > > On Wed, May 06, 2009 at 05:35:18PM +0100, Ralf Baechle wrote:
> > >> On Mon, May 04, 2009 at 03:57:19PM -0700, David VomLehn wrote:
> > >>
> > >>> Most platforms can get by perfectly well with the default command line 
> > >>> size,
> > >>> but some platforms need more. This patch allows the command line size to
> > >>> be configured for those platforms that need it. The default remains 256
> > >>> characters.
> > >>>
> > >>> Signed-off-by: David VomLehn <dvomlehn@cisco.com>
> > >> How big of a command line do you need?  For no scientific reason other
> > >> than there not being any obvious need for a larger size MIPS is using 256
> > >> and I think unless you're asking for a huge number it will be better to
> > >> just raise that constant.
> > > 
> > > The answer depends on the platform, but it's at 438 characters on a 
> > > typical
> > > platform. If I *had* to pick a number, I'd probably go for 512 
> > > characters; I
> > > just hate to force others to use memory they aren't going to use.
> > > 
> > 
> > I wonder if the memory could be dynamically allocated.  It would of 
> > course be a much larger patch.
> > 
> > David Daney
> 
> A bit of a chicken and egg problem if your command line arguments
> set the memory configuration.
> 
> Jon Fraser

You could wait for a final copy of the command line until *after* you have at
least the boot memory allocator working. Then other buffers used to hold
the command line would be __initdata.  Sounds like a bit of work, though, and
it might be kind of fragile for such a small gain in memory.

David VomLehn