[PATCH 1/3 V3] time: move timeconst.h into include/generated

Nicholas Mc Guire
2015-05-18T12:27:44Z

kernel/time/timeconst.h is moved to include/generated/ and generated
by the top level Kbuild. This allows using timeconst.h in an earlier
build stage.

Patch was build tested for:
arm - imx_v6_v7_defconfig, vexpress_defconfig
cris - etrax-100lx_v2_defconfig
m68k - multi_defconfig
mips32 - ar7_defconfig,
mips64 - loongson3_defconfig
powerpc - 44x/virtex5_defconfig
powerpc64 - powerpc64_defconfig
sh - se7780_defconfig,
sparc32 - sparc32_defconfig
sparc64 - sparc64_defconfig
x86 64 - x86_64_defconfig,

Patch is against 4.1-rc3 (localversion-next is -next-20150518)

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
---

Thanks to Joe Perches <joe@perches.com> for suggesting this approach
and catching the unconditional rebuild (should be fixed here now
properly) as well as for his review comments on the first attempts.

V3: minor change in top level Kbuild to make mips64 build correctly
(timeconst.h added to dependency list of asm-offset.h)

Kbuild | 34 +++++++++++++++++++++++++++-------
kernel/time/Makefile | 17 +----------------
kernel/time/time.c | 2 +-
kernel/time/timeconst.bc | 3 ++-
4 files changed, 31 insertions(+), 25 deletions(-)

diff --git a/Kbuild b/Kbuild
index 6f0d82a..df99a5f 100644
--- a/Kbuild
+++ b/Kbuild
@@ -2,8 +2,9 @@
# Kbuild for top-level directory of the kernel
# This file takes care of the following:
# 1) Generate bounds.h
-# 2) Generate asm-offsets.h (may need bounds.h)
-# 3) Check for missing system calls
+# 2) Generate timeconst.h
+# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
+# 4) Check for missing system calls

# Default sed regexp - multiline due to syntax constraints
define sed-y
@@ -47,7 +48,26 @@ $(obj)/$(bounds-file): kernel/bounds.s FORCE
$(call filechk,offsets,__LINUX_BOUNDS_H__)

#####
-# 2) Generate asm-offsets.h
+# 2) Generate timeconst.h
+
+timeconst-file := include/generated/timeconst.h
+
+#always += $(timeconst-file)
+targets += $(timeconst-file)
+
+quiet_cmd_gentimeconst = GEN $@
+define cmd_gentimeconst
+ (echo $(CONFIG_HZ) | bc -q $< ) > $@
+endef
+define filechk_gentimeconst
+ (echo $(CONFIG_HZ) | bc -q $< )
+endef
+
+$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
+ $(call filechk,gentimeconst)
+
+#####
+# 3) Generate asm-offsets.h
#

offsets-file := include/generated/asm-offsets.h
@@ -57,7 +77,7 @@ targets += arch/$(SRCARCH)/kernel/asm-offsets.s

# We use internal kbuild rules to avoid the "is up to date" message from make
arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
- $(obj)/$(bounds-file) FORCE
+ $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
$(Q)mkdir -p $(dir $@)
$(call if_changed_dep,cc_s_c)

@@ -65,7 +85,7 @@ $(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
$(call filechk,offsets,__ASM_OFFSETS_H__)

#####
-# 3) Check for missing system calls
+# 4) Check for missing system calls
#

always += missing-syscalls
@@ -77,5 +97,5 @@ quiet_cmd_syscalls = CALL $<
missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
$(call cmd,syscalls)

-# Keep these two files during make clean
-no-clean-files := $(bounds-file) $(offsets-file)
+# Keep these three files during make clean
+no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
index 01f0312..ffc4cc3 100644
--- a/kernel/time/Makefile
+++ b/kernel/time/Makefile
@@ -13,19 +13,4 @@ obj-$(CONFIG_TIMER_STATS) += timer_stats.o
obj-$(CONFIG_DEBUG_FS) += timekeeping_debug.o
obj-$(CONFIG_TEST_UDELAY) += test_udelay.o

-$(obj)/time.o: $(obj)/timeconst.h
-
-quiet_cmd_hzfile = HZFILE $@
- cmd_hzfile = echo "hz=$(CONFIG_HZ)" > $@
-
-targets += hz.bc
-$(obj)/hz.bc: $(objtree)/include/config/hz.h FORCE
- $(call if_changed,hzfile)
-
-quiet_cmd_bc = BC $@
- cmd_bc = bc -q $(filter-out FORCE,$^) > $@
-
-targets += timeconst.h
-$(obj)/timeconst.h: $(obj)/hz.bc $(src)/timeconst.bc FORCE
- $(call if_changed,bc)
-
+$(obj)/time.o: $(objtree)/include/config/
diff --git a/kernel/time/time.c b/kernel/time/time.c
index 2c85b77..4fa1d26 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -41,7 +41,7 @@
#include <asm/uaccess.h>
#include <asm/unistd.h>

-#include "timeconst.h"
+#include <generated/timeconst.h>
#include "timekeeping.h"

/*
diff --git a/kernel/time/timeconst.bc b/kernel/time/timeconst.bc
index 511bdf2..c7388de 100644
--- a/kernel/time/timeconst.bc
+++ b/kernel/time/timeconst.bc
@@ -50,7 +50,7 @@ define timeconst(hz) {
print "#include <linux/types.h>\n\n"

print "#if HZ != ", hz, "\n"
- print "#error \qkernel/timeconst.h has the wrong HZ value!\q\n"
+ print "#error \qinclude/generated/timeconst.h has the wrong HZ value!\q\n"
print "#endif\n\n"

if (hz < 2) {
@@ -105,4 +105,5 @@ define timeconst(hz) {
halt
}

+hz = read();
timeconst(hz)
--
1.7.10.4