[PATCH u-boot v2.1 38/38] ARM: enable LTO for some boards

Marek Behun marek.behun at nic.cz
Fri Mar 12 18:36:05 CET 2021 

On Fri, 12 Mar 2021 18:19:08 +0100
Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:

> On 12.03.21 18:03, Marek Behun wrote:
> > On Fri, 12 Mar 2021 08:34:41 -0800
> > Tim Harvey <tharvey at gateworks.com> wrote:
> >  
> >> On Fri, Mar 12, 2021 at 5:47 AM Marek Behún <marek.behun at nic.cz> wrote:  
> >>>
> >>> Enable LTO for some boards that were tested by people on U-Boot Mailing
> >>> List.
> >>>
> >>> Signed-off-by: Marek Behún <marek.behun at nic.cz>
> >>> Tested-by: Adam Ford <aford173 at gmail.com>
> >>> Tested-by: Pali Rohár <pali at kernel.org>
> >>> Tested-by: Tim Harvey <tharvey at gateworks.com>
> >>> ---
> >>>  configs/am3517_evm_defconfig          | 1 +
> >>>  configs/da850evm_defconfig            | 1 +
> >>>  configs/da850evm_direct_nor_defconfig | 1 +
> >>>  configs/da850evm_nand_defconfig       | 1 +
> >>>  configs/imx6q_logic_defconfig         | 1 +
> >>>  configs/imx8mm_beacon_defconfig       | 1 +
> >>>  configs/imx8mm_venice_defconfig       | 1 +
> >>>  configs/imx8mn_beacon_2g_defconfig    | 1 +
> >>>  configs/imx8mn_beacon_defconfig       | 1 +
> >>>  configs/nokia_rx51_defconfig          | 1 +
> >>>  configs/omap3_logic_defconfig         | 1 +
> >>>  configs/r8a774a1_beacon_defconfig     | 1 +
> >>>  configs/r8a774b1_beacon_defconfig     | 1 +
> >>>  configs/r8a774e1_beacon_defconfig     | 1 +
> >>>  configs/turris_mox_defconfig          | 1 +
> >>>  configs/turris_omnia_defconfig        | 1 +
> >>>  16 files changed, 16 insertions(+)
> >>>
> >>> diff --git a/configs/am3517_evm_defconfig b/configs/am3517_evm_defconfig
> >>> index bae0e0af35..d61eec94a4 100644
> >>> --- a/configs/am3517_evm_defconfig
> >>> +++ b/configs/am3517_evm_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  # CONFIG_SPL_USE_ARCH_MEMCPY is not set
> >>>  # CONFIG_SPL_USE_ARCH_MEMSET is not set
> >>> diff --git a/configs/da850evm_defconfig b/configs/da850evm_defconfig
> >>> index 26e76a2929..6ff5e21bc6 100644
> >>> --- a/configs/da850evm_defconfig
> >>> +++ b/configs/da850evm_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_SYS_THUMB_BUILD=y
> >>>  CONFIG_ARCH_DAVINCI=y
> >>> diff --git a/configs/da850evm_direct_nor_defconfig b/configs/da850evm_direct_nor_defconfig
> >>> index d3860a963d..06c7ce7c47 100644
> >>> --- a/configs/da850evm_direct_nor_defconfig
> >>> +++ b/configs/da850evm_direct_nor_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_CPU_INIT=y
> >>>  CONFIG_ARCH_DAVINCI=y
> >>> diff --git a/configs/da850evm_nand_defconfig b/configs/da850evm_nand_defconfig
> >>> index 0d0e9a148d..be737564e1 100644
> >>> --- a/configs/da850evm_nand_defconfig
> >>> +++ b/configs/da850evm_nand_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_SYS_THUMB_BUILD=y
> >>>  CONFIG_ARCH_DAVINCI=y
> >>> diff --git a/configs/imx6q_logic_defconfig b/configs/imx6q_logic_defconfig
> >>> index 36dc24d080..0f8aea6983 100644
> >>> --- a/configs/imx6q_logic_defconfig
> >>> +++ b/configs/imx6q_logic_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_MX6=y
> >>>  CONFIG_SYS_TEXT_BASE=0x17800000
> >>> diff --git a/configs/imx8mm_beacon_defconfig b/configs/imx8mm_beacon_defconfig
> >>> index 045b19f4f3..e8bb44eea6 100644
> >>> --- a/configs/imx8mm_beacon_defconfig
> >>> +++ b/configs/imx8mm_beacon_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_IMX8M=y
> >>>  CONFIG_SYS_TEXT_BASE=0x40200000
> >>> diff --git a/configs/imx8mm_venice_defconfig b/configs/imx8mm_venice_defconfig
> >>> index a15c3641f6..dff8f64540 100644
> >>> --- a/configs/imx8mm_venice_defconfig
> >>> +++ b/configs/imx8mm_venice_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_IMX8M=y
> >>>  CONFIG_SYS_TEXT_BASE=0x40200000
> >>> diff --git a/configs/imx8mn_beacon_2g_defconfig b/configs/imx8mn_beacon_2g_defconfig
> >>> index 58b8e49486..1c8cbc2c89 100644
> >>> --- a/configs/imx8mn_beacon_2g_defconfig
> >>> +++ b/configs/imx8mn_beacon_2g_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_IMX8M=y
> >>>  CONFIG_SYS_TEXT_BASE=0x40200000
> >>> diff --git a/configs/imx8mn_beacon_defconfig b/configs/imx8mn_beacon_defconfig
> >>> index d6a3385d8d..6457b9409a 100644
> >>> --- a/configs/imx8mn_beacon_defconfig
> >>> +++ b/configs/imx8mn_beacon_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_IMX8M=y
> >>>  CONFIG_SYS_TEXT_BASE=0x40200000
> >>> diff --git a/configs/nokia_rx51_defconfig b/configs/nokia_rx51_defconfig
> >>> index 312ca3a1a9..85ca627790 100644
> >>> --- a/configs/nokia_rx51_defconfig
> >>> +++ b/configs/nokia_rx51_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  # CONFIG_SYS_THUMB_BUILD is not set
> >>>  CONFIG_ARCH_OMAP2PLUS=y
> >>> diff --git a/configs/omap3_logic_defconfig b/configs/omap3_logic_defconfig
> >>> index 4e37237b86..cc4b727a2c 100644
> >>> --- a/configs/omap3_logic_defconfig
> >>> +++ b/configs/omap3_logic_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  # CONFIG_SPL_USE_ARCH_MEMCPY is not set
> >>>  # CONFIG_SPL_USE_ARCH_MEMSET is not set
> >>> diff --git a/configs/r8a774a1_beacon_defconfig b/configs/r8a774a1_beacon_defconfig
> >>> index 2f45edd92e..9dd5d9192e 100644
> >>> --- a/configs/r8a774a1_beacon_defconfig
> >>> +++ b/configs/r8a774a1_beacon_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_RMOBILE=y
> >>>  CONFIG_SYS_TEXT_BASE=0x50000000
> >>> diff --git a/configs/r8a774b1_beacon_defconfig b/configs/r8a774b1_beacon_defconfig
> >>> index ca514bb1aa..b7d7f23f5a 100644
> >>> --- a/configs/r8a774b1_beacon_defconfig
> >>> +++ b/configs/r8a774b1_beacon_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_RMOBILE=y
> >>>  CONFIG_SYS_TEXT_BASE=0x50000000
> >>> diff --git a/configs/r8a774e1_beacon_defconfig b/configs/r8a774e1_beacon_defconfig
> >>> index b89729d92a..3e44edf29f 100644
> >>> --- a/configs/r8a774e1_beacon_defconfig
> >>> +++ b/configs/r8a774e1_beacon_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_RMOBILE=y
> >>>  CONFIG_SYS_TEXT_BASE=0x50000000
> >>> diff --git a/configs/turris_mox_defconfig b/configs/turris_mox_defconfig
> >>> index f938fbb475..2a351d9180 100644
> >>> --- a/configs/turris_mox_defconfig
> >>> +++ b/configs/turris_mox_defconfig
> >>> @@ -1,3 +1,4 @@
> >>> +CONFIG_LTO=y
> >>>  CONFIG_ARM=y
> >>>  CONFIG_ARCH_CPU_INIT=y
> >>>  CONFIG_ARCH_MVEBU=y
> >>> diff --git a/configs/turris_omnia_defconfig b/configs/turris_omnia_defconfig
> >>> index 4b8843d7be..d7a2ec3592 100644
> >>> --- a/configs/turris_omnia_defconfig
> >>> +++ b/configs/turris_omnia_defconfig
> >>> @@ -1,3 +1,4 @@  
> >>> +CONFIG_LTO=y>>>  CONFIG_ARM=y  
> >>>  CONFIG_ARCH_CPU_INIT=y
> >>>  CONFIG_SPL_SYS_THUMB_BUILD=y
> >>> --
> >>> 2.26.2
> >>>  
> >>
> >> Marek,
> >>
> >> Perhaps I didn't test the property test before as I did not realize
> >> there was a config to be enabled.
> >>
> >> Enabling CONFIG_LTO breaks linking the SPL (linking uboot is fine):
> >>   LTO     spl/u-boot-spl
> >> make[2]: *** read jobs pipe: No such file or directory.  Stop.
> >> make[2]: *** Waiting for unfinished jobs....
> >> lto-wrapper: fatal error: make returned 2 exit status
> >> compilation terminated.
> >> /usr/src/venice/buildroot/output/host/lib/gcc/aarch64-buildroot-linux-gnu/9.3.0/../../../../aarch64-buildroot-linux-gnu/bin/ld:
> >> error: lto-wrapper failed
> >> collect2: error: ld returned 1 exit status
> >> scripts/Makefile.spl:461: recipe for target 'spl/u-boot-spl' failed
> >> make[1]: *** [spl/u-boot-spl] Error 1
> >> Makefile:1985: recipe for target 'spl/u-boot-spl' failed
> >> make: *** [spl/u-boot-spl] Error 2
> >>
> >> I'm using your lto branch
> >>
> >> Best Regards,
> >>
> >> Tim  
> >
> > Tim, try compiling with only one job, i.e.
> >   make -j1
> >  
> 
> If parallel build fails, we have a bug in the Makefile. It worked fine
> without the LTO patches.

It may be a problem with GNU make's jobserver. Tom mentioned that
there is a known race condition or something...

If only there was a simple way to discover inside the Makefile the
number of jobs given to the make command via the -j parameter, we could
use -flto=$(JOBS).

I found this
https://blog.jgc.org/2015/03/gnu-make-insanity-finding-value-of-j.html

Marek

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