[PATCH 2/3] Kprobes: Define retval helper

[Ananth N Mavinakayanahalli <ananth@in.ibm.com>]

From: Ananth N Mavinakayanahalli <ananth@in.ibm.com>

Add the KPROBE_RETVAL macro to help extract the return value on
different architectures, while using function-return probes.

---
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Prasanna S.P <prasanna@in.ibm.com>


---
 include/asm-i386/kprobes.h    |    2 ++
 include/asm-ia64/kprobes.h    |    2 ++
 include/asm-powerpc/kprobes.h |    2 ++
 include/asm-x86_64/kprobes.h  |    2 ++
 4 files changed, 8 insertions(+)

Index: linux-2.6.18-rc3/include/asm-i386/kprobes.h
===================================================================
--- linux-2.6.18-rc3.orig/include/asm-i386/kprobes.h
+++ linux-2.6.18-rc3/include/asm-i386/kprobes.h
@@ -46,6 +46,8 @@ typedef u8 kprobe_opcode_t;
 #define ARCH_SUPPORTS_KRETPROBES
 #define  ARCH_INACTIVE_KPROBE_COUNT 0
 
+#define KPROBE_RETVAL(regs)	regs->eax
+
 void arch_remove_kprobe(struct kprobe *p);
 void kretprobe_trampoline(void);
 
Index: linux-2.6.18-rc3/include/asm-ia64/kprobes.h
===================================================================
--- linux-2.6.18-rc3.orig/include/asm-ia64/kprobes.h
+++ linux-2.6.18-rc3/include/asm-ia64/kprobes.h
@@ -84,6 +84,8 @@ struct kprobe_ctlblk {
 #define ARCH_SUPPORTS_KRETPROBES
 #define  ARCH_INACTIVE_KPROBE_COUNT 1
 
+#define KPROBE_RETVAL(regs)	regs->r8
+
 #define SLOT0_OPCODE_SHIFT	(37)
 #define SLOT1_p1_OPCODE_SHIFT	(37 - (64-46))
 #define SLOT2_OPCODE_SHIFT 	(37)
Index: linux-2.6.18-rc3/include/asm-powerpc/kprobes.h
===================================================================
--- linux-2.6.18-rc3.orig/include/asm-powerpc/kprobes.h
+++ linux-2.6.18-rc3/include/asm-powerpc/kprobes.h
@@ -54,6 +54,8 @@ typedef unsigned int kprobe_opcode_t;
 #define ARCH_SUPPORTS_KRETPROBES
 #define  ARCH_INACTIVE_KPROBE_COUNT 1
 
+#define KPROBE_RETVAL(regs)	regs->gpr[3]
+
 void kretprobe_trampoline(void);
 extern void arch_remove_kprobe(struct kprobe *p);
 
Index: linux-2.6.18-rc3/include/asm-x86_64/kprobes.h
===================================================================
--- linux-2.6.18-rc3.orig/include/asm-x86_64/kprobes.h
+++ linux-2.6.18-rc3/include/asm-x86_64/kprobes.h
@@ -45,6 +45,8 @@ typedef u8 kprobe_opcode_t;
 #define ARCH_SUPPORTS_KRETPROBES
 #define  ARCH_INACTIVE_KPROBE_COUNT 1
 
+#define KPROBE_RETVAL(regs)	regs->rax
+
 void kretprobe_trampoline(void);
 extern void arch_remove_kprobe(struct kprobe *p);