From 7bf99fb673f18408be1ebc958321ef4c3f6da9e2 Mon Sep 17 00:00:00 2001
From: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Date: Wed, 17 Jun 2009 16:28:09 -0700
Subject: 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>
---
 arch/x86/kernel/Makefile | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'arch/x86/kernel/Makefile')

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index f3477bb84566..6c327b852e23 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
-- 
cgit v1.2.2


From f386c61fe1a1f36f0e434f1b577e6b112698caf7 Mon Sep 17 00:00:00 2001
From: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Date: Sun, 5 Jul 2009 12:08:06 -0700
Subject: gcov: exclude code operating in userspace from profiling

Fix for this issue on x86_64:

rostedt@goodmis.org wrote:
> On bootup of the latest kernel my init segfaults. Debugging it,
> I found  that vread_tsc (a vsyscall) increments some strange
> kernel memory:
>
> 0000000000000000 <vread_tsc>:
>    0:   55                      push   %rbp
>    1:   48 ff 05 00 00 00 00    incq   0(%rip)
>                         # 8 <vread_tsc+0x8>
>                         4: R_X86_64_PC32        .bss+0x3c
>    8:   48 89 e5                mov    %rsp,%rbp
>    b:   66 66 90                xchg   %ax,%ax
>    e:   48 ff 05 00 00 00 00    incq   0(%rip)
>                         # 15 <vread_tsc+0x15>
>                         11: R_X86_64_PC32       .bss+0x44
>   15:   66 66 90                xchg   %ax,%ax
>   18:   48 ff 05 00 00 00 00    incq   0(%rip)
>                         # 1f <vread_tsc+0x1f>
>                         1b: R_X86_64_PC32       .bss+0x4c
>   1f:   0f 31                   rdtsc
>
>
> Those "incq" is very bad to happen in vsyscall memory, since
> userspace can not modify it. You need to make something prevent
> profiling of vsyscall  memory (like I do with ftrace).

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/x86/kernel/Makefile | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'arch/x86/kernel/Makefile')

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 6c327b852e23..430d5b24af7b 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -26,6 +26,8 @@ CFLAGS_tsc.o		:= $(nostackp)
 CFLAGS_paravirt.o	:= $(nostackp)
 GCOV_PROFILE_vsyscall_64.o	:= n
 GCOV_PROFILE_hpet.o		:= n
+GCOV_PROFILE_tsc.o		:= n
+GCOV_PROFILE_paravirt.o		:= n
 
 obj-y			:= process_$(BITS).o signal.o entry_$(BITS).o
 obj-y			+= traps.o irq.o irq_$(BITS).o dumpstack_$(BITS).o
-- 
cgit v1.2.2