[ARM] 5382/1: unwind: Reorganise the stacktrace support

This patch changes the walk_stacktrace and its callers for easier
integration of stack unwinding. The arch/arm/kernel/stacktrace.h file is
also moved to arch/arm/include/asm/stacktrace.h.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 15 insertions, 6 deletions

diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c
index c68b44aa88d2..4cdc4a0bd02d 100644
--- a/arch/arm/kernel/time.c
+++ b/arch/arm/kernel/time.c
@@ -33,6 +33,7 @@
 
 #include <asm/leds.h>
 #include <asm/thread_info.h>
+#include <asm/stacktrace.h>
 #include <asm/mach/time.h>
 
 /*
@@ -55,14 +56,22 @@ EXPORT_SYMBOL(rtc_lock);
 #ifdef CONFIG_SMP
 unsigned long profile_pc(struct pt_regs *regs)
 {
-        unsigned long fp, pc = instruction_pointer(regs);
+        struct stackframe frame;
 
-        if (in_lock_functions(pc)) {
-                fp = regs->ARM_fp;
-                pc = ((unsigned long *)fp)[-1];
-        }
+        if (!in_lock_functions(regs->ARM_pc))
+                return regs->ARM_pc;
+
+        frame.fp = regs->ARM_fp;
+        frame.sp = regs->ARM_sp;
+        frame.lr = regs->ARM_lr;
+        frame.pc = regs->ARM_pc;
+        do {
+                int ret = unwind_frame(&frame);
+                if (ret < 0)
+                        return 0;
+        } while (in_lock_functions(frame.pc));
 
-        return pc;
+        return frame.pc;
 }
 EXPORT_SYMBOL(profile_pc);
 #endif