gcov: enable GCOV_PROFILE_ALL for x86_64

Enable gcov profiling of the entire kernel on x86_64. Required changes
include disabling profiling for:

* arch/kernel/acpi/realmode and arch/kernel/boot/compressed:
  not linked to main kernel
* arch/vdso, arch/kernel/vsyscall_64 and arch/kernel/hpet:
  profiling causes segfaults during boot (incompatible context)

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Li Wei <W.Li@Sun.COM>
Cc: Michael Ellerman <michaele@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 7 insertions, 1 deletions

diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 8d16ada2504..ec749c2bfdd 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -70,6 +70,7 @@ KBUILD_CFLAGS	:= $(LINUXINCLUDE) -g -Os -D_SETUP -D__KERNEL__ \
                    $(call cc-option, -mpreferred-stack-boundary=2)
 KBUILD_CFLAGS   += $(call cc-option, -m32)
 KBUILD_AFLAGS   := $(KBUILD_CFLAGS) -D__ASSEMBLY__
+GCOV_PROFILE := n
 
 $(obj)/bzImage: asflags-y  := $(SVGA_MODE)
 
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 49c8a4c37d7..e2ff504b4dd 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -15,6 +15,7 @@ KBUILD_CFLAGS += $(call cc-option,-ffreestanding)
 KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
 
 KBUILD_AFLAGS  := $(KBUILD_CFLAGS) -D__ASSEMBLY__
+GCOV_PROFILE := n
 
 LDFLAGS := -m elf_$(UTS_MACHINE)
 LDFLAGS_vmlinux := -T
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index f3477bb8456..6c327b852e2 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -24,6 +24,8 @@ CFLAGS_vsyscall_64.o	:= $(PROFILING) -g0 $(nostackp)
 CFLAGS_hpet.o           := $(nostackp)
 CFLAGS_tsc.o            := $(nostackp)
 CFLAGS_paravirt.o       := $(nostackp)
+GCOV_PROFILE_vsyscall_64.o      := n
+GCOV_PROFILE_hpet.o             := n
 
 obj-y                   := process_$(BITS).o signal.o entry_$(BITS).o
 obj-y                   += traps.o irq.o irq_$(BITS).o dumpstack_$(BITS).o
diff --git a/arch/x86/kernel/acpi/realmode/Makefile b/arch/x86/kernel/acpi/realmode/Makefile
index 167bc16ce0e..6a564ac67ef 100644
--- a/arch/x86/kernel/acpi/realmode/Makefile
+++ b/arch/x86/kernel/acpi/realmode/Makefile
@@ -42,6 +42,7 @@ KBUILD_CFLAGS	:= $(LINUXINCLUDE) -g -Os -D_SETUP -D_WAKEUP -D__KERNEL__ \
                    $(call cc-option, -mpreferred-stack-boundary=2)
 KBUILD_CFLAGS   += $(call cc-option, -m32)
 KBUILD_AFLAGS   := $(KBUILD_CFLAGS) -D__ASSEMBLY__
+GCOV_PROFILE := n
 
 WAKEUP_OBJS = $(addprefix $(obj)/,$(wakeup-y))
 
diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index 16a9020c8f1..88112b49f02 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -123,6 +123,7 @@ quiet_cmd_vdso = VDSO    $@
                        -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^)
 
 VDSO_LDFLAGS = -fPIC -shared $(call ld-option, -Wl$(comma)--hash-style=sysv)
+GCOV_PROFILE := n
 
 #
 # Install the unstripped copy of vdso*.so listed in $(vdso-install-y).
diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index aab593abfba..22e9dcfaa3d 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -34,7 +34,7 @@ config GCOV_KERNEL
 config GCOV_PROFILE_ALL
         bool "Profile entire Kernel"
         depends on GCOV_KERNEL
-        depends on S390 || X86_32
+        depends on S390 || X86
         default n
         ---help---
         This options activates profiling for the entire kernel.