[PATCH] ARM: at91: move platform-specific asm-offset.h to arch/arm/mach-at91

From: Masahiro Yamada
Date: Thu Aug 22 2019 - 22:45:22 EST


<generated/at91_pm_data-offsets.h> is only generated and included by
arch/arm/mach-at91/, so it does not need to reside in the globally
visible include/generated/.

I renamed it to arch/arm/mach-at91/pm_data-offsets.h since the prefix
'at91_' is just redundant in mach-at91/.

My main motivation of this change is to avoid the race condition for
the parallel build (-j) when CONFIG_IKHEADERS is enabled.

When it is enabled, all the headers under include/ are archived into
kernel/kheaders_data.tar.xz and exposed in the sysfs.

In the parallel build, we have no idea in which order files are built.

- If at91_pm_data-offsets.h is built before kheaders_data.tar.xz,
the header will be included in the archive. Probably nobody will
use it, but it is harmless except that it will increase the archive
size needlessly.

- If kheaders_data.tar.xz is built before at91_pm_data-offsets.h,
the header will not be included in the archive. However, in the next
build, the archive will be re-generated to include the newly-found
at91_pm_data-offsets.h. This is not nice from the build system point
of view.

- If at91_pm_data-offsets.h and kheaders_data.tar.xz are built at the
same time, the corrupted header might be included in the archive,
which does not look nice either.

This commit fixes the race.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

arch/arm/mach-at91/.gitignore | 1 +
arch/arm/mach-at91/Makefile | 5 +++--
arch/arm/mach-at91/pm_suspend.S | 2 +-
3 files changed, 5 insertions(+), 3 deletions(-)
create mode 100644 arch/arm/mach-at91/.gitignore

diff --git a/arch/arm/mach-at91/.gitignore b/arch/arm/mach-at91/.gitignore
new file mode 100644
index 000000000000..2ecd6f51c8a9
--- /dev/null
+++ b/arch/arm/mach-at91/.gitignore
@@ -0,0 +1 @@
+pm_data-offsets.h
diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
index 31b61f0e1c07..de64301dcff2 100644
--- a/arch/arm/mach-at91/Makefile
+++ b/arch/arm/mach-at91/Makefile
@@ -19,9 +19,10 @@ ifeq ($(CONFIG_PM_DEBUG),y)
CFLAGS_pm.o += -DDEBUG
endif

-include/generated/at91_pm_data-offsets.h: arch/arm/mach-at91/pm_data-offsets.s FORCE
+$(obj)/pm_data-offsets.h: $(obj)/pm_data-offsets.s FORCE
$(call filechk,offsets,__PM_DATA_OFFSETS_H__)

-arch/arm/mach-at91/pm_suspend.o: include/generated/at91_pm_data-offsets.h
+$(obj)/pm_suspend.o: $(obj)/pm_data-offsets.h

targets += pm_data-offsets.s
+clean-files += pm_data-offsets.h
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index c751f047b116..ed57c879d4e1 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -10,7 +10,7 @@
#include <linux/linkage.h>
#include <linux/clk/at91_pmc.h>
#include "pm.h"
-#include "generated/at91_pm_data-offsets.h"
+#include "pm_data-offsets.h"

#define SRAMC_SELF_FRESH_ACTIVE 0x01
#define SRAMC_SELF_FRESH_EXIT 0x00
--
2.17.1