diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-27 08:01:22 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-27 08:01:22 +0300 |
commit | 5b26fc8824da15a2fe9df89338a5a3cad41ba8ee (patch) | |
tree | 04dd34173591e2275a754053c86b06cc1e72cebe | |
parent | e12fab28df1d7ae9369839a3af260a41447a5e79 (diff) | |
parent | c9c6837d39311b0cc14cdbe7c18e815ab44aefb1 (diff) | |
download | linux-5b26fc8824da15a2fe9df89338a5a3cad41ba8ee.tar.xz |
Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:
- new option CONFIG_TRIM_UNUSED_KSYMS which does a two-pass build and
unexports symbols which are not used in the current config [Nicolas
Pitre]
- several kbuild rule cleanups [Masahiro Yamada]
- warning option adjustments for gcov etc [Arnd Bergmann]
- a few more small fixes
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (31 commits)
kbuild: move -Wunused-const-variable to W=1 warning level
kbuild: fix if_change and friends to consider argument order
kbuild: fix adjust_autoksyms.sh for modules that need only one symbol
kbuild: fix ksym_dep_filter when multiple EXPORT_SYMBOL() on the same line
gcov: disable -Wmaybe-uninitialized warning
gcov: disable tree-loop-im to reduce stack usage
gcov: disable for COMPILE_TEST
Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES
Kbuild: change CC_OPTIMIZE_FOR_SIZE definition
kbuild: forbid kernel directory to contain spaces and colons
kbuild: adjust ksym_dep_filter for some cmd_* renames
kbuild: Fix dependencies for final vmlinux link
kbuild: better abstract vmlinux sequential prerequisites
kbuild: fix call to adjust_autoksyms.sh when output directory specified
kbuild: Get rid of KBUILD_STR
kbuild: rename cmd_as_s_S to cmd_cpp_s_S
kbuild: rename cmd_cc_i_c to cmd_cpp_i_c
kbuild: drop redundant "PHONY += FORCE"
kbuild: delete unnecessary "@:"
kbuild: mark help target as PHONY
...
29 files changed, 335 insertions, 95 deletions
@@ -128,6 +128,10 @@ _all: # Cancel implicit rules on top Makefile $(CURDIR)/Makefile Makefile: ; +ifneq ($(words $(subst :, ,$(CURDIR))), 1) + $(error main directory cannot contain spaces nor colons) +endif + ifneq ($(KBUILD_OUTPUT),) # Invoke a second make in the output directory, passing relevant variables # check that the output directory actually exists @@ -142,7 +146,7 @@ PHONY += $(MAKECMDGOALS) sub-make $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make @: -sub-make: FORCE +sub-make: $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \ -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS)) @@ -364,7 +368,7 @@ AFLAGS_MODULE = LDFLAGS_MODULE = CFLAGS_KERNEL = AFLAGS_KERNEL = -CFLAGS_GCOV = -fprofile-arcs -ftest-coverage +CFLAGS_GCOV = -fprofile-arcs -ftest-coverage -fno-tree-loop-im -Wno-maybe-uninitialized CFLAGS_KCOV = -fsanitize-coverage=trace-pc @@ -617,7 +621,11 @@ KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,) ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,) else -KBUILD_CFLAGS += -O2 +ifdef CONFIG_PROFILE_ALL_BRANCHES +KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,) +else +KBUILD_CFLAGS += -O2 +endif endif # Tell gcc to never replace conditional load with a non-conditional one @@ -697,9 +705,10 @@ KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,) KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior) else -# This warning generated too much noise in a regular build. -# Use make W=1 to enable this warning (see scripts/Makefile.build) +# These warnings generated too much noise in a regular build. +# Use make W=1 to enable them (see scripts/Makefile.build) KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) +KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable) endif ifdef CONFIG_FRAME_POINTER @@ -926,27 +935,41 @@ export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Doc vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) -# Final link of vmlinux - cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) -quiet_cmd_link-vmlinux = LINK $@ - -# Include targets which we want to -# execute if the rest of the kernel build went well. -vmlinux: scripts/link-vmlinux.sh $(vmlinux-deps) FORCE +# Include targets which we want to execute sequentially if the rest of the +# kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be +# evaluated more than once. +PHONY += vmlinux_prereq +vmlinux_prereq: $(vmlinux-deps) FORCE ifdef CONFIG_HEADERS_CHECK $(Q)$(MAKE) -f $(srctree)/Makefile headers_check endif -ifdef CONFIG_SAMPLES - $(Q)$(MAKE) $(build)=samples -endif ifdef CONFIG_BUILD_DOCSRC $(Q)$(MAKE) $(build)=Documentation endif ifdef CONFIG_GDB_SCRIPTS $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py endif +ifdef CONFIG_TRIM_UNUSED_KSYMS + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \ + "$(MAKE) KBUILD_MODULES=1 -f $(srctree)/Makefile vmlinux_prereq" +endif + +# standalone target for easier testing +include/generated/autoksyms.h: FORCE + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true + +# Final link of vmlinux + cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) +quiet_cmd_link-vmlinux = LINK $@ + +vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE +$(call if_changed,link-vmlinux) +# Build samples along the rest of the kernel +ifdef CONFIG_SAMPLES +vmlinux-dirs += samples +endif + # The actual objects are generated when descending, # make sure no implicit rule kicks in $(sort $(vmlinux-deps)): $(vmlinux-dirs) ; @@ -998,10 +1021,12 @@ prepare2: prepare3 outputmakefile asm-generic prepare1: prepare2 $(version_h) include/generated/utsrelease.h \ include/config/auto.conf $(cmd_crmodverdir) + $(Q)test -e include/generated/autoksyms.h || \ + touch include/generated/autoksyms.h archprepare: archheaders archscripts prepare1 scripts_basic -prepare0: archprepare FORCE +prepare0: archprepare $(Q)$(MAKE) $(build)=. # All the preparing.. @@ -1061,7 +1086,7 @@ INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware export INSTALL_FW_PATH PHONY += firmware_install -firmware_install: FORCE +firmware_install: @mkdir -p $(objtree)/firmware $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install @@ -1081,7 +1106,7 @@ PHONY += archscripts archscripts: PHONY += __headers -__headers: $(version_h) scripts_basic asm-generic archheaders archscripts FORCE +__headers: $(version_h) scripts_basic asm-generic archheaders archscripts $(Q)$(MAKE) $(build)=scripts build_unifdef PHONY += headers_install_all @@ -1192,7 +1217,8 @@ else # CONFIG_MODULES # Modules not configured # --------------------------------------------------------------------------- -modules modules_install: FORCE +PHONY += modules modules_install +modules modules_install: @echo >&2 @echo >&2 "The present kernel configuration has modules disabled." @echo >&2 "Type 'make config' and enable loadable module support." @@ -1283,6 +1309,7 @@ boards := $(sort $(notdir $(boards))) board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig)) board-dirs := $(sort $(notdir $(board-dirs:/=))) +PHONY += help help: @echo 'Cleaning targets:' @echo ' clean - Remove most generated files but keep the config and' @@ -1453,6 +1480,7 @@ $(clean-dirs): clean: rm-dirs := $(MODVERDIR) clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers +PHONY += help help: @echo ' Building external modules.' @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target' diff --git a/arch/arm/boot/Makefile b/arch/arm/boot/Makefile index 446705a4325a..5be33a2d59a9 100644 --- a/arch/arm/boot/Makefile +++ b/arch/arm/boot/Makefile @@ -82,7 +82,6 @@ $(obj)/uImage: $(obj)/zImage FORCE $(obj)/bootp/bootp: $(obj)/zImage initrd FORCE $(Q)$(MAKE) $(build)=$(obj)/bootp $@ - @: $(obj)/bootpImage: $(obj)/bootp/bootp FORCE $(call if_changed,objcopy) diff --git a/arch/arm/boot/bootp/Makefile b/arch/arm/boot/bootp/Makefile index 5761f0039133..5e4acd253b30 100644 --- a/arch/arm/boot/bootp/Makefile +++ b/arch/arm/boot/bootp/Makefile @@ -17,7 +17,6 @@ targets := bootp init.o kernel.o initrd.o # Note that bootp.lds picks up kernel.o and initrd.o $(obj)/bootp: $(src)/bootp.lds $(addprefix $(obj)/,init.o kernel.o initrd.o) FORCE $(call if_changed,ld) - @: # kernel.o and initrd.o includes a binary image using # .incbin, a dependency which is not tracked automatically @@ -26,4 +25,4 @@ $(obj)/kernel.o: arch/arm/boot/zImage FORCE $(obj)/initrd.o: $(INITRD) FORCE -PHONY += $(INITRD) FORCE +PHONY += $(INITRD) diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile index 1160434eece0..59a8fa7b8a3b 100644 --- a/arch/arm/vdso/Makefile +++ b/arch/arm/vdso/Makefile @@ -74,5 +74,5 @@ $(MODLIB)/vdso: FORCE @mkdir -p $(MODLIB)/vdso PHONY += vdso_install -vdso_install: $(obj)/vdso.so.dbg $(MODLIB)/vdso FORCE +vdso_install: $(obj)/vdso.so.dbg $(MODLIB)/vdso $(call cmd,vdso_install) diff --git a/arch/h8300/boot/compressed/Makefile b/arch/h8300/boot/compressed/Makefile index 7643633f1330..613bfe6f5272 100644 --- a/arch/h8300/boot/compressed/Makefile +++ b/arch/h8300/boot/compressed/Makefile @@ -23,7 +23,6 @@ LDFLAGS_vmlinux := -Ttext $(IMAGE_OFFSET) -estartup -T $(obj)/vmlinux.lds \ $(obj)/vmlinux: $(OBJECTS) $(obj)/piggy.o $(LIBGCC) FORCE $(call if_changed,ld) - @: $(obj)/vmlinux.bin: vmlinux FORCE $(call if_changed,objcopy) diff --git a/arch/ia64/Makefile b/arch/ia64/Makefile index 970d0bd99621..c100d780f1eb 100644 --- a/arch/ia64/Makefile +++ b/arch/ia64/Makefile @@ -95,8 +95,8 @@ define archhelp echo '* unwcheck - Check vmlinux for invalid unwind info' endef -archprepare: make_nr_irqs_h FORCE -PHONY += make_nr_irqs_h FORCE +archprepare: make_nr_irqs_h +PHONY += make_nr_irqs_h -make_nr_irqs_h: FORCE +make_nr_irqs_h: $(Q)$(MAKE) $(build)=arch/ia64/kernel include/generated/nr-irqs.h diff --git a/arch/m32r/boot/compressed/Makefile b/arch/m32r/boot/compressed/Makefile index 01729c2979ba..0606a727aab2 100644 --- a/arch/m32r/boot/compressed/Makefile +++ b/arch/m32r/boot/compressed/Makefile @@ -19,7 +19,6 @@ LDFLAGS_vmlinux := -T $(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS) $(obj)/piggy.o FORCE $(call if_changed,ld) - @: $(obj)/vmlinux.bin: vmlinux FORCE $(call if_changed,objcopy) diff --git a/arch/mn10300/boot/compressed/Makefile b/arch/mn10300/boot/compressed/Makefile index 08a95e171685..5f56f9de1061 100644 --- a/arch/mn10300/boot/compressed/Makefile +++ b/arch/mn10300/boot/compressed/Makefile @@ -8,7 +8,6 @@ LDFLAGS_vmlinux := -Ttext $(CONFIG_KERNEL_ZIMAGE_BASE_ADDRESS) -e startup_32 $(obj)/vmlinux: $(obj)/head.o $(obj)/misc.o $(obj)/piggy.o FORCE $(call if_changed,ld) - @: $(obj)/vmlinux.bin: vmlinux FORCE $(call if_changed,objcopy) diff --git a/arch/nios2/boot/compressed/Makefile b/arch/nios2/boot/compressed/Makefile index 5b0fb346d888..d5921c9a9726 100644 --- a/arch/nios2/boot/compressed/Makefile +++ b/arch/nios2/boot/compressed/Makefile @@ -11,7 +11,6 @@ LDFLAGS_vmlinux := -T $(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS) $(obj)/piggy.o FORCE $(call if_changed,ld) - @: LDFLAGS_piggy.o := -r --format binary --oformat elf32-littlenios2 -T diff --git a/arch/s390/boot/compressed/Makefile b/arch/s390/boot/compressed/Makefile index fac6ac9790fa..1dd210347e12 100644 --- a/arch/s390/boot/compressed/Makefile +++ b/arch/s390/boot/compressed/Makefile @@ -22,7 +22,6 @@ OBJECTS += $(obj)/head.o $(obj)/misc.o $(obj)/piggy.o LDFLAGS_vmlinux := --oformat $(LD_BFD) -e startup -T $(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS) $(call if_changed,ld) - @: sed-sizes := -e 's/^\([0-9a-fA-F]*\) . \(__bss_start\|_end\)$$/\#define SZ\2 0x\1/p' diff --git a/arch/sh/boot/compressed/Makefile b/arch/sh/boot/compressed/Makefile index 6df826ee7316..c4c47ea9fa94 100644 --- a/arch/sh/boot/compressed/Makefile +++ b/arch/sh/boot/compressed/Makefile @@ -55,7 +55,6 @@ $(addprefix $(obj)/,$(lib1funcs-y)): $(obj)/%: $(lib1funcs-dir)/% FORCE $(obj)/vmlinux: $(OBJECTS) $(obj)/piggy.o $(lib1funcs-obj) FORCE $(call if_changed,ld) - @: $(obj)/vmlinux.bin: vmlinux FORCE $(call if_changed,objcopy) diff --git a/arch/sh/boot/romimage/Makefile b/arch/sh/boot/romimage/Makefile index 2216ee57f251..43c41191de5d 100644 --- a/arch/sh/boot/romimage/Makefile +++ b/arch/sh/boot/romimage/Makefile @@ -17,7 +17,6 @@ LDFLAGS_vmlinux := --oformat $(ld-bfd) -Ttext $(load-y) -e romstart \ $(obj)/vmlinux: $(obj)/head.o $(obj-y) $(obj)/piggy.o FORCE $(call if_changed,ld) - @: OBJCOPYFLAGS += -j .empty_zero_page diff --git a/arch/unicore32/boot/Makefile b/arch/unicore32/boot/Makefile index ec7fb70b412b..828855007b29 100644 --- a/arch/unicore32/boot/Makefile +++ b/arch/unicore32/boot/Makefile @@ -31,7 +31,7 @@ $(obj)/uImage: $(obj)/zImage FORCE $(call if_changed,uimage) @echo ' Image $@ is ready' -PHONY += initrd FORCE +PHONY += initrd initrd: @test "$(INITRD)" != "" || \ (echo You must specify INITRD; exit -1) diff --git a/arch/unicore32/boot/compressed/Makefile b/arch/unicore32/boot/compressed/Makefile index 96494fb646f7..9aecdd3ddc48 100644 --- a/arch/unicore32/boot/compressed/Makefile +++ b/arch/unicore32/boot/compressed/Makefile @@ -54,7 +54,6 @@ LDFLAGS_vmlinux += -T $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/head.o $(obj)/piggy.o \ $(obj)/misc.o FORCE $(call if_changed,ld) - @: # We now have a PIC decompressor implementation. Decompressors running # from RAM should not define ZTEXTADDR. Decompressors running directly diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index cfdd8c3f8af2..f1356889204e 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -87,7 +87,6 @@ vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o $(obj)/vmlinux: $(vmlinux-objs-y) FORCE $(call if_changed,ld) - @: OBJCOPYFLAGS_vmlinux.bin := -R .comment -S $(obj)/vmlinux.bin: vmlinux FORCE diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 6874da5f67fc..253b72eaade6 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -193,10 +193,10 @@ vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%) $(MODLIB)/vdso: FORCE @mkdir -p $(MODLIB)/vdso -$(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso FORCE +$(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso $(call cmd,vdso_install) PHONY += vdso_install $(vdso_img_insttargets) -vdso_install: $(vdso_img_insttargets) FORCE +vdso_install: $(vdso_img_insttargets) clean-files := vdso32.so vdso32.so.dbg vdso64* vdso-image-*.c vdsox32.so* diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile index 92e3e1d84c1d..12734a96df47 100644 --- a/arch/x86/purgatory/Makefile +++ b/arch/x86/purgatory/Makefile @@ -26,7 +26,5 @@ quiet_cmd_bin2c = BIN2C $@ $(obj)/kexec-purgatory.c: $(obj)/purgatory.ro FORCE $(call if_changed,bin2c) - @: - obj-$(CONFIG_KEXEC_FILE) += kexec-purgatory.o diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile index b95964610ea7..c556c5ae8de5 100644 --- a/arch/x86/realmode/rm/Makefile +++ b/arch/x86/realmode/rm/Makefile @@ -59,7 +59,6 @@ OBJCOPYFLAGS_realmode.bin := -O binary targets += realmode.bin $(obj)/realmode.bin: $(obj)/realmode.elf $(obj)/realmode.relocs FORCE $(call if_changed,objcopy) - @: quiet_cmd_relocs = RELOCS $@ cmd_relocs = arch/x86/tools/relocs --realmode $< > $@ diff --git a/include/linux/export.h b/include/linux/export.h index 96e45ea463e7..2f9ccbe6a639 100644 --- a/include/linux/export.h +++ b/include/linux/export.h @@ -38,7 +38,7 @@ extern struct module __this_module; #ifdef CONFIG_MODULES -#ifndef __GENKSYMS__ +#if defined(__KERNEL__) && !defined(__GENKSYMS__) #ifdef CONFIG_MODVERSIONS /* Mark the CRC weak since genksyms apparently decides not to * generate a checksums for some symbols */ @@ -53,7 +53,7 @@ extern struct module __this_module; #endif /* For every exported symbol, place a struct in the __ksymtab section */ -#define __EXPORT_SYMBOL(sym, sec) \ +#define ___EXPORT_SYMBOL(sym, sec) \ extern typeof(sym) sym; \ __CRC_SYMBOL(sym, sec) \ static const char __kstrtab_##sym[] \ @@ -65,6 +65,35 @@ extern struct module __this_module; __attribute__((section("___ksymtab" sec "+" #sym), unused)) \ = { (unsigned long)&sym, __kstrtab_##sym } +#if defined(__KSYM_DEPS__) + +/* + * For fine grained build dependencies, we want to tell the build system + * about each possible exported symbol even if they're not actually exported. + * We use a string pattern that is unlikely to be valid code that the build + * system filters out from the preprocessor output (see ksym_dep_filter + * in scripts/Kbuild.include). + */ +#define __EXPORT_SYMBOL(sym, sec) === __KSYM_##sym === + +#elif defined(CONFIG_TRIM_UNUSED_KSYMS) + +#include <linux/kconfig.h> +#include <generated/autoksyms.h> + +#define __EXPORT_SYMBOL(sym, sec) \ + __cond_export_sym(sym, sec, config_enabled(__KSYM_##sym)) +#define __cond_export_sym(sym, sec, conf) \ + ___cond_export_sym(sym, sec, conf) +#define ___cond_export_sym(sym, sec, enabled) \ + __cond_export_sym_##enabled(sym, sec) +#define __cond_export_sym_1(sym, sec) ___EXPORT_SYMBOL(sym, sec) +#define __cond_export_sym_0(sym, sec) /* nothing */ + +#else +#define __EXPORT_SYMBOL ___EXPORT_SYMBOL +#endif + #define EXPORT_SYMBOL(sym) \ __EXPORT_SYMBOL(sym, "") diff --git a/init/Kconfig b/init/Kconfig index a9c4aefd5436..f755a602d4a1 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1306,6 +1306,17 @@ source "usr/Kconfig" endif +choice + prompt "Compiler optimization level" + default CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE + +config CC_OPTIMIZE_FOR_PERFORMANCE + bool "Optimize for performance" + help + This is the default optimization level for the kernel, building + with the "-O2" compiler flag for best performance and most + helpful compile-time warnings. + config CC_OPTIMIZE_FOR_SIZE bool "Optimize for size" help @@ -1314,6 +1325,8 @@ config CC_OPTIMIZE_FOR_SIZE If unsure, say N. +endchoice + config SYSCTL bool @@ -2049,6 +2062,22 @@ config MODULE_COMPRESS_XZ endchoice +config TRIM_UNUSED_KSYMS + bool "Trim unused exported kernel symbols" + depends on MODULES && !UNUSED_SYMBOLS + help + The kernel and some modules make many symbols available for + other modules to use via EXPORT_SYMBOL() and variants. Depending + on the set of modules being selected in your kernel configuration, + many of those exported symbols might never be used. + + This option allows for unused exported symbols to be dropped from + the build. In turn, this provides the compiler more opportunities + (especially when using LTO) for optimizing the code and reducing + binary size. This might have some security advantages as well. + + If unsure say N. + endif # MODULES config MODULES_TREE_LOOKUP diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig index c92e44855ddd..1276aabaab55 100644 --- a/kernel/gcov/Kconfig +++ b/kernel/gcov/Kconfig @@ -37,6 +37,7 @@ config ARCH_HAS_GCOV_PROFILE_ALL config GCOV_PROFILE_ALL bool "Profile entire Kernel" + depends on !COMPILE_TEST depends on GCOV_KERNEL depends on ARCH_HAS_GCOV_PROFILE_ALL default n diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index b2ab2a92a375..0f82314621f2 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -7,6 +7,7 @@ quote := " squote := ' empty := space := $(empty) $(empty) +space_escape := _-_SPACE_-_ ### # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o @@ -226,10 +227,10 @@ objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) # See Documentation/kbuild/makefiles.txt for more info ifneq ($(KBUILD_NOCMDDEP),1) -# Check if both arguments has same arguments. Result is empty string if equal. -# User may override this check using make KBUILD_NOCMDDEP=1 -arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \ - $(filter-out $(cmd_$@), $(cmd_$(1))) ) +# Check if both arguments are the same including their order. Result is empty +# string if equal. User may override this check using make KBUILD_NOCMDDEP=1 +arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ + $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) else arg-check = $(if $(strip $(cmd_$@)),,1) endif @@ -256,10 +257,42 @@ if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ # Execute the command and also postprocess generated .d dependencies file. if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ @set -e; \ + $(cmd_and_fixdep), @:) + +ifndef CONFIG_TRIM_UNUSED_KSYMS + +cmd_and_fixdep = \ $(echo-cmd) $(cmd_$(1)); \ scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ rm -f $(depfile); \ - mv -f $(dot-target).tmp $(dot-target).cmd, @:) + mv -f $(dot-target).tmp $(dot-target).cmd; + +else + +# Filter out exported kernel symbol names from the preprocessor output. +# See also __KSYM_DEPS__ in include/linux/export.h. +# We disable the depfile generation here, so as not to overwrite the existing +# depfile while fixdep is parsing it. +flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1))) +ksym_dep_filter = \ + case "$(1)" in \ + cc_*_c|cpp_i_c) \ + $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \ + as_*_S|cpp_s_S) \ + $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \ + boot*|build*|*cpp_lds_S|dtc|host*|vdso*) : ;; \ + *) echo "Don't know how to preprocess $(1)" >&2; false ;; \ + esac | tr ";" "\n" | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p' + +cmd_and_fixdep = \ + $(echo-cmd) $(cmd_$(1)); \ + $(ksym_dep_filter) | \ + scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \ + > $(dot-target).tmp; \ + rm -f $(depfile); \ + mv -f $(dot-target).tmp $(dot-target).cmd; + +endif # Usage: $(call if_changed_rule,foo) # Will check if $(cmd_foo) or any of the prerequisites changed, @@ -341,8 +374,6 @@ endif # ############################################################################### # -space_escape := %%%SPACE%%% -# define config_filename ifneq ($$(CONFIG_$(1)),"") $(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1))))))) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index e1bc1907090e..0d1ca5bf42fb 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -152,11 +152,11 @@ cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $< $(obj)/%.s: $(src)/%.c FORCE $(call if_changed_dep,cc_s_c) -quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@ -cmd_cc_i_c = $(CPP) $(c_flags) -o $@ $< +quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@ +cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $< $(obj)/%.i: $(src)/%.c FORCE - $(call if_changed_dep,cc_i_c) + $(call if_changed_dep,cpp_i_c) cmd_gensymtypes = \ $(CPP) -D__GENKSYMS__ $(c_flags) $< | \ @@ -266,26 +266,24 @@ endif # CONFIG_STACK_VALIDATION define rule_cc_o_c $(call echo-cmd,checksrc) $(cmd_checksrc) \ - $(call echo-cmd,cc_o_c) $(cmd_cc_o_c); \ + $(call cmd_and_fixdep,cc_o_c) \ $(cmd_modversions) \ - $(cmd_objtool) \ - $(call echo-cmd,record_mcount) \ - $(cmd_record_mcount) \ - scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' > \ - $(dot-target).tmp; \ - rm -f $(depfile); \ - mv -f $(dot-target).tmp $(dot-target).cmd + $(cmd_objtool) \ + $(call echo-cmd,record_mcount) $(cmd_record_mcount) endef define rule_as_o_S - $(call echo-cmd,as_o_S) $(cmd_as_o_S); \ - $(cmd_objtool) \ - scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,as_o_S)' > \ - $(dot-target).tmp; \ - rm -f $(depfile); \ - mv -f $(dot-target).tmp $(dot-target).cmd + $(call cmd_and_fixdep,as_o_S) \ + $(cmd_objtool) endef +# List module undefined symbols (or empty line if not enabled) +ifdef CONFIG_TRIM_UNUSED_KSYMS +cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo +else +cmd_undef_syms = echo +endif + # Built-in and composite module parts $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE $(call cmd,force_checksrc) @@ -296,7 +294,8 @@ $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE $(call cmd,force_checksrc) $(call if_changed_rule,cc_o_c) - @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod) + @{ echo $(@:.o=.ko); echo $@; \ + $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod) quiet_cmd_cc_lst_c = MKLST $@ cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \ @@ -314,11 +313,11 @@ modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL) $(real-objs-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE) $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE) -quiet_cmd_as_s_S = CPP $(quiet_modtag) $@ -cmd_as_s_S = $(CPP) $(a_flags) -o $@ $< +quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@ +cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $< $(obj)/%.s: $(src)/%.S FORCE - $(call if_changed_dep,as_s_S) + $(call if_changed_dep,cpp_s_S) quiet_cmd_as_o_S = AS $(quiet_modtag) $@ cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< @@ -426,7 +425,8 @@ $(call multi_depend, $(multi-used-y), .o, -objs -y) $(multi-used-m): FORCE $(call if_changed,link_multi-m) - @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod) + @{ echo $(@:.o=.ko); echo $(link_multi_deps); \ + $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod) $(call multi_depend, $(multi-used-m), .o, -objs -y -m) targets += $(multi-used-y) $(multi-used-m) diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index f9e47a70509c..53449a6ff6aa 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -24,6 +24,7 @@ warning-1 += $(call cc-option, -Wmissing-prototypes) warning-1 += -Wold-style-definition warning-1 += $(call cc-option, -Wmissing-include-dirs) warning-1 += $(call cc-option, -Wunused-but-set-variable) +warning-1 += $(call cc-option, -Wunused-const-variable) warning-1 += $(call cc-disable-warning, missing-field-initializers) warning-1 += $(call cc-disable-warning, sign-compare) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index ed1b7c4fb674..e7df0f5db7ec 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -96,10 +96,10 @@ obj-dirs := $(addprefix $(obj)/,$(obj-dirs)) # Note: Files that end up in two or more modules are compiled without the # KBUILD_MODNAME definition. The reason is that any made-up name would # differ in different configs. -name-fix = $(subst $(comma),_,$(subst -,_,$1)) -basename_flags = -D"KBUILD_BASENAME=KBUILD_STR($(call name-fix,$(basetarget)))" +name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) +basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) modname_flags = $(if $(filter 1,$(words $(modname))),\ - -D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))") + -DKBUILD_MODNAME=$(call name-fix,$(modname))) orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \ $(ccflags-y) $(CFLAGS_$(basetarget).o) @@ -162,7 +162,7 @@ endif c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ $(__c_flags) $(modkern_cflags) \ - -D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags) + $(basename_flags) $(modname_flags) a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ $(__a_flags) $(modkern_aflags) diff --git a/scripts/adjust_autoksyms.sh b/scripts/adjust_autoksyms.sh new file mode 100755 index 000000000000..8dc1918b6783 --- /dev/null +++ b/scripts/adjust_autoksyms.sh @@ -0,0 +1,101 @@ +#!/bin/sh + +# Script to create/update include/generated/autoksyms.h and dependency files +# +# Copyright: (C) 2016 Linaro Limited +# Created by: Nicolas Pitre, January 2016 +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 2 as +# published by the Free Software Foundation. + +# Create/update the include/generated/autoksyms.h file from the list +# of all module's needed symbols as recorded on the third line of +# .tmp_versions/*.mod files. +# +# For each symbol being added or removed, the corresponding dependency +# file's timestamp is updated to force a rebuild of the affected source +# file. All arguments passed to this script are assumed to be a command +# to be exec'd to trigger a rebuild of those files. + +set -e + +cur_ksyms_file="include/generated/autoksyms.h" +new_ksyms_file="include/generated/autoksyms.h.tmpnew" + +info() { + if [ "$quiet" != "silent_" ]; then + printf " %-7s %s\n" "$1" "$2" + fi +} + +info "CHK" "$cur_ksyms_file" + +# Use "make V=1" to debug this script. +case "$KBUILD_VERBOSE" in +*1*) + set -x + ;; +esac + +# We need access to CONFIG_ symbols +case "${KCONFIG_CONFIG}" in +*/*) + . "${KCONFIG_CONFIG}" + ;; +*) + # Force using a file from the current directory + . "./${KCONFIG_CONFIG}" +esac + +# In case it doesn't exist yet... +if [ -e "$cur_ksyms_file" ]; then touch "$cur_ksyms_file"; fi + +# Generate a new ksym list file with symbols needed by the current +# set of modules. +cat > "$new_ksyms_file" << EOT +/* + * Automatically generated file; DO NOT EDIT. + */ + +EOT +sed -ns -e '3{s/ /\n/g;/^$/!p;}' "$MODVERDIR"/*.mod | sort -u | +while read sym; do + if [ -n "$CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX" ]; then + sym="${sym#_}" + fi + echo "#define __KSYM_${sym} 1" +done >> "$new_ksyms_file" + +# Special case for modversions (see modpost.c) +if [ -n "$CONFIG_MODVERSIONS" ]; then + echo "#define __KSYM_module_layout 1" >> "$new_ksyms_file" +fi + +# Extract changes between old and new list and touch corresponding +# dependency files. +changed=$( +count=0 +sort "$cur_ksyms_file" "$new_ksyms_file" | uniq -u | +sed -n 's/^#define __KSYM_\(.*\) 1/\1/p' | tr "A-Z_" "a-z/" | +while read sympath; do + if [ -z "$sympath" ]; then continue; fi + depfile="include/config/ksym/${sympath}.h" + mkdir -p "$(dirname "$depfile")" + touch "$depfile" + echo $((count += 1)) +done | tail -1 ) +changed=${changed:-0} + +if [ $changed -gt 0 ]; then + # Replace the old list with tne new one + old=$(grep -c "^#define __KSYM_" "$cur_ksyms_file" || true) + new=$(grep -c "^#define __KSYM_" "$new_ksyms_file" || true) + info "KSYMS" "symbols: before=$old, after=$new, changed=$changed" + info "UPD" "$cur_ksyms_file" + mv -f "$new_ksyms_file" "$cur_ksyms_file" + # Then trigger a rebuild of affected source files + exec $@ +else + rm -f "$new_ksyms_file" +fi diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c index caef815d1743..746ec1ece614 100644 --- a/scripts/basic/fixdep.c +++ b/scripts/basic/fixdep.c @@ -120,13 +120,15 @@ #define INT_NFIG ntohl(0x4e464947) #define INT_FIG_ ntohl(0x4649475f) +int insert_extra_deps; char *target; char *depfile; char *cmdline; static void usage(void) { - fprintf(stderr, "Usage: fixdep <depfile> <target> <cmdline>\n"); + fprintf(stderr, "Usage: fixdep [-e] <depfile> <target> <cmdline>\n"); + fprintf(stderr, " -e insert extra dependencies given on stdin\n"); exit(1); } @@ -138,6 +140,40 @@ static void print_cmdline(void) printf("cmd_%s := %s\n\n", target, cmdline); } +/* + * Print out a dependency path from a symbol name + */ +static void print_config(const char *m, int slen) +{ + int c, i; + + printf(" $(wildcard include/config/"); + for (i = 0; i < slen; i++) { + c = m[i]; + if (c == '_') + c = '/'; + else + c = tolower(c); + putchar(c); + } + printf(".h) \\\n"); +} + +static void do_extra_deps(void) +{ + if (insert_extra_deps) { + char buf[80]; + while(fgets(buf, sizeof(buf), stdin)) { + int len = strlen(buf); + if (len < 2 || buf[len-1] != '\n') { + fprintf(stderr, "fixdep: bad data on stdin\n"); + exit(1); + } + print_config(buf, len-1); + } + } +} + struct item { struct item *next; unsigned int len; @@ -197,23 +233,12 @@ static void define_config(const char *name, int len, unsigned int hash) static void use_config(const char *m, int slen) { unsigned int hash = strhash(m, slen); - int c, i; if (is_defined_config(m, slen, hash)) return; define_config(m, slen, hash); - - printf(" $(wildcard include/config/"); - for (i = 0; i < slen; i++) { - c = m[i]; - if (c == '_') - c = '/'; - else - c = tolower(c); - putchar(c); - } - printf(".h) \\\n"); + print_config(m, slen); } static void parse_config_file(const char *map, size_t len) @@ -250,7 +275,7 @@ static void parse_config_file(const char *map, size_t len) } } -/* test is s ends in sub */ +/* test if s ends in sub */ static int strrcmp(const char *s, const char *sub) { int slen = strlen(s); @@ -333,6 +358,7 @@ static void parse_dep_file(void *map, size_t len) /* Ignore certain dependencies */ if (strrcmp(s, "include/generated/autoconf.h") && + strrcmp(s, "include/generated/autoksyms.h") && strrcmp(s, "arch/um/include/uml-config.h") && strrcmp(s, "include/linux/kconfig.h") && strrcmp(s, ".ver")) { @@ -378,6 +404,8 @@ static void parse_dep_file(void *map, size_t len) exit(1); } + do_extra_deps(); + printf("\n%s: $(deps_%s)\n\n", target, target); printf("$(deps_%s):\n", target); } @@ -434,7 +462,10 @@ int main(int argc, char *argv[]) { traps(); - if (argc != 4) + if (argc == 5 && !strcmp(argv[1], "-e")) { + insert_extra_deps = 1; + argv++; + } else if (argc != 4) usage(); depfile = argv[1]; diff --git a/scripts/genksyms/genksyms.c b/scripts/genksyms/genksyms.c index dafaf96e0a34..06121ce524a7 100644 --- a/scripts/genksyms/genksyms.c +++ b/scripts/genksyms/genksyms.c @@ -873,5 +873,8 @@ int main(int argc, char **argv) (double)nsyms / (double)HASH_BUCKETS); } + if (dumpfile) + fclose(dumpfile); + return errors != 0; } diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build index ee566e8bd1cf..27f3583193e6 100644 --- a/tools/build/Makefile.build +++ b/tools/build/Makefile.build @@ -58,8 +58,8 @@ quiet_cmd_mkdir = MKDIR $(dir $@) quiet_cmd_cc_o_c = CC $@ cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< -quiet_cmd_cc_i_c = CPP $@ - cmd_cc_i_c = $(CC) $(c_flags) -E -o $@ $< +quiet_cmd_cpp_i_c = CPP $@ + cmd_cpp_i_c = $(CC) $(c_flags) -E -o $@ $< quiet_cmd_cc_s_c = AS $@ cmd_cc_s_c = $(CC) $(c_flags) -S -o $@ $< @@ -83,11 +83,11 @@ $(OUTPUT)%.o: %.S FORCE $(OUTPUT)%.i: %.c FORCE $(call rule_mkdir) - $(call if_changed_dep,cc_i_c) + $(call if_changed_dep,cpp_i_c) $(OUTPUT)%.s: %.S FORCE $(call rule_mkdir) - $(call if_changed_dep,cc_i_c) + $(call if_changed_dep,cpp_i_c) $(OUTPUT)%.s: %.c FORCE $(call rule_mkdir) |