Date: Fri, 28 Sep 2007 12:27:15 -0700
From: Greg KH <greg@kroah.com>
To: Denys Vlasenko <vda.linux@googlemail.com>
Cc: tapio.laxstrom@iptime.fi, linux-kernel@vger.kernel.org
Subject: Re: drivers/usb/misc/emi*.c have the biggest data objects in the
	whole tree
Message-ID: <20070928192715.GC8385@kroah.com>
References: <200709141135.35239.vda.linux@googlemail.com> <20070928044111.GB24458@kroah.com> <200709281234.29646.vda.linux@googlemail.com>
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On Fri, Sep 28, 2007 at 12:34:29PM +0100, Denys Vlasenko wrote:
> On Friday 28 September 2007 05:41, Greg KH wrote:
> > On Fri, Sep 14, 2007 at 11:35:34AM +0100, Denys Vlasenko wrote:
> > > Hi Tapio,
> > > 
> > > You are the author of these files. Are you still maintaining them?
> > > If not, do you know who is the current maintainer?
> > > 
> > > These two object files hold the biggest data objects in the whole Linux kernel
> > > after lockdep:
> > > 
> > >    text    data     bss     dec     hex filename
> > >    1258  160516       0  161774   277ee ./drivers/usb/misc/emi26.o
> > >    1504  209296       0  210800   33770 ./drivers/usb/misc/emi62.o
> > > 
> > > Basically, these are big arrays of the following structures:
> > > 
> > > typedef struct _INTEL_HEX_RECORD
> > > {
> > >         __u32   length;
> > >         __u32   address;
> > >         __u32   type;
> > >         __u8    data[MAX_INTEL_HEX_RECORD_LENGTH];
> > > } INTEL_HEX_RECORD;
> > > 
> > > I suggest the following optimizations:
> > > 
> > > Change structure to
> > > 
> > > typedef struct _INTEL_HEX_RECORD
> > > {
> > >         __u8   type;
> > >         __u8   length;
> > >         __u16   address;
> > >         __u8    data[MAX_INTEL_HEX_RECORD_LENGTH];
> > > } INTEL_HEX_RECORD __attribute__((__packed__));
> > 
> > Only if you redo the whole firmware image too :)
> 
> I did. It wasn't hard.

Great, send me a patch then :)

> > What is this really hurting?  It's only relevant if you load the
> > specific module
> 
> By this logic, no space wastage in modules is worth fixing.

No, that's not true.  Be realistic here please.

thanks,

greg k-h
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