[U-Boot] [PATCH] Reduce build times

[Graeme Russ <graeme.russ@gmail.com>]

Hi Wolfgang,

On 02/11/11 17:54, Wolfgang Denk wrote:
> U-Boot Makefiles contain a number of tests for compiler features etc.
> which so far are executed again and again.  On some architectures
> (especially ARM) this results in a large number of calls to gcc.
> 
> This patch makes sure to run such tests only once, thus largely
> reducing the number of "execve" system calls.
> 
> Example: number of "execve" system calls for building the "P2020DS"
> (Power Architecture) and "qong" (ARM) boards, measured as:
> 	-> strace -f -e trace=execve -o /tmp/foo ./MAKEALL <board>
> 	-> grep execve /tmp/foo | wc -l
> 
> 	Before: After:	Reduction:
> ==================================
> P2020DS 20555	15205	-26%
> qong	31692	14490	-54%
> 
> As a result, built times are significantly reduced, typically by
> 30...50%.
> 
> Signed-off-by: Wolfgang Denk <wd@denx.de>
> Cc: Andy Fleming <afleming@gmail.com>
> Cc: Kumar Gala <galak@kernel.crashing.org>
> Cc: Albert Aribaud <albert.aribaud@free.fr>
> cc: Graeme Russ <graeme.russ@gmail.com>
> cc: Mike Frysinger <vapier@gentoo.org>
> ---

Tested on x86, does what is written on the box ;)

Tested-by: Graeme Russ <graeme.russ@gmail.com>

Regards,

Graeme