Reduce build times
authorWolfgang Denk <wd@denx.de>
Tue, 1 Nov 2011 20:54:02 +0000 (20:54 +0000)
committerWolfgang Denk <wd@denx.de>
Thu, 3 Nov 2011 19:44:58 +0000 (20:44 +0100)
commitcca4e4aec1fe52e5ecd15e3cebdbb36e2f254220
tree58737a4eeeedb099b8a71f8dfacb11a810e1d4fb
parent4d6402b012b074f4658785773c97745963c52dc5
Reduce build times

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-by: Graeme Russ <graeme.russ@gmail.com>
Tested-by: Matthias Weisser <weisserm@arcor.de>
Tested-by: Sanjeev Premi <premi@ti.com>
Tested-by: Simon Glass <sjg@chromium.org>
Tested-by: Macpaul Lin <macpaul@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
25 files changed:
Makefile
arch/arm/config.mk
arch/arm/cpu/arm1136/config.mk
arch/arm/cpu/arm1176/config.mk
arch/arm/cpu/arm1176/s3c64xx/config.mk
arch/arm/cpu/arm720t/config.mk
arch/arm/cpu/arm920t/config.mk
arch/arm/cpu/arm925t/config.mk
arch/arm/cpu/arm926ejs/at91/config.mk
arch/arm/cpu/arm926ejs/config.mk
arch/arm/cpu/arm946es/config.mk
arch/arm/cpu/arm_intcm/config.mk
arch/arm/cpu/armv7/config.mk
arch/arm/cpu/armv7/omap-common/config.mk
arch/arm/cpu/ixp/config.mk
arch/arm/cpu/lh7a40x/config.mk
arch/arm/cpu/pxa/config.mk
arch/arm/cpu/s3c44b0/config.mk
arch/arm/cpu/sa1100/config.mk
arch/powerpc/cpu/mpc824x/Makefile
arch/powerpc/cpu/mpc85xx/config.mk
arch/x86/config.mk
board/siemens/SCM/Makefile
config.mk
examples/standalone/Makefile