sh: ftrace: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack

The structure of the ret_stack array on the task struct is going to
change, and accessing it directly via the curr_ret_stack index will no
longer give the ret_stack entry that holds the return address. To access
that, architectures must now use ftrace_graph_get_ret_stack() to get the
associated ret_stack that matches the saved return address.

Cc: linux-sh@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

2 files changed, 12 insertions, 8 deletions

diff --git a/arch/sh/kernel/dumpstack.c b/arch/sh/kernel/dumpstack.c
index b564b1eae4ae..2c2e151bf39e 100644
--- a/arch/sh/kernel/dumpstack.c
+++ b/arch/sh/kernel/dumpstack.c
@@ -59,17 +59,20 @@ print_ftrace_graph_addr(unsigned long addr, void *data,
                         struct thread_info *tinfo, int *graph)
 {
         struct task_struct *task = tinfo->task;
+        struct ftrace_ret_stack *ret_stack;
         unsigned long ret_addr;
-        int index = task->curr_ret_stack;
 
         if (addr != (unsigned long)return_to_handler)
                 return;
 
-        if (!task->ret_stack || index < *graph)
+        if (!task->ret_stack)
                 return;
 
-        index -= *graph;
-        ret_addr = task->ret_stack[index].ret;
+        ret_stack = ftrace_graph_get_ret_stack(task, *graph);
+        if (!ret_stack)
+                return;
+
+        ret_addr = ret_stack->ret;
 
         ops->address(data, ret_addr, 1);
 
diff --git a/arch/sh/kernel/dwarf.c b/arch/sh/kernel/dwarf.c
index bb511e2d9d68..df0fd6efe758 100644
--- a/arch/sh/kernel/dwarf.c
+++ b/arch/sh/kernel/dwarf.c
@@ -608,17 +608,18 @@ struct dwarf_frame *dwarf_unwind_stack(unsigned long pc,
          * expected to find the real return address.
          */
         if (pc == (unsigned long)&return_to_handler) {
-                int index = current->curr_ret_stack;
+                struct ftrace_ret_stack *ret_stack;
 
+                ret_stack = ftrace_graph_get_ret_stack(current, 0);
+                if (ret_stack)
+                        pc = ret_stack->ret;
                 /*
                  * We currently have no way of tracking how many
                  * return_to_handler()'s we've seen. If there is more
                  * than one patched return address on our stack,
                  * complain loudly.
                  */
-                WARN_ON(index > 0);
-
-                pc = current->ret_stack[index].ret;
+                WARN_ON(ftrace_graph_get_ret_stack(current, 1);
         }
 #endif