[PATCH] powerpc: export validate_sp for oprofile calltrace

Export validate_sp so we can use it in the oprofile calltrace code.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/kernel/process.c

@@ -770,7 +770,7 @@ int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
 	return error;
 }
 
-static int validate_sp(unsigned long sp, struct task_struct *p,
+int validate_sp(unsigned long sp, struct task_struct *p,
 		       unsigned long nbytes)
 {
 	unsigned long stack_page = (unsigned long)task_stack_page(p);
@@ -808,6 +808,8 @@ static int validate_sp(unsigned long sp, struct task_struct *p,
 #define FRAME_MARKER	2
 #endif
 
+EXPORT_SYMBOL(validate_sp);
+
 unsigned long get_wchan(struct task_struct *p)
 {
 	unsigned long ip, sp;

include/asm-powerpc/processor.h

@@ -251,6 +251,10 @@ static inline unsigned long __pack_fe01(unsigned int fpmode)
 #define cpu_relax()	barrier()
 #endif
 
+/* Check that a certain kernel stack pointer is valid in task_struct p */
+int validate_sp(unsigned long sp, struct task_struct *p,
+                       unsigned long nbytes);
+
 /*
  * Prefetch macros.
  */