[MIPS] lockdep: Add STACKTRACE_SUPPORT and enable LOCKDEP_SUPPORT

Implement stacktrace interface by using unwind_stack() and enable lockdep
support in Kconfig.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 3 insertions, 34 deletions

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index e51d8fd9a152..440b8651fd8b 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -41,6 +41,7 @@
 #include <asm/mmu_context.h>
 #include <asm/watch.h>
 #include <asm/types.h>
+#include <asm/stacktrace.h>
 
 extern asmlinkage void handle_int(void);
 extern asmlinkage void handle_tlbm(void);
@@ -92,16 +93,14 @@ static void show_raw_backtrace(unsigned long reg29)
 }
 
 #ifdef CONFIG_KALLSYMS
-static int raw_show_trace;
+int raw_show_trace;
 static int __init set_raw_show_trace(char *str)
 {
         raw_show_trace = 1;
         return 1;
 }
 __setup("raw_show_trace", set_raw_show_trace);
-
-extern unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
-                                  unsigned long pc, unsigned long ra);
+#endif
 
 static void show_backtrace(struct task_struct *task, struct pt_regs *regs)
 {
@@ -121,9 +120,6 @@ static void show_backtrace(struct task_struct *task, struct pt_regs *regs)
         } while (pc);
         printk("\n");
 }
-#else
-#define show_backtrace(task, r) show_raw_backtrace((r)->regs[29]);
-#endif
 
 /*
  * This routine abuses get_user()/put_user() to reference pointers
@@ -158,28 +154,6 @@ static void show_stacktrace(struct task_struct *task, struct pt_regs *regs)
         show_backtrace(task, regs);
 }
 
-static __always_inline void prepare_frametrace(struct pt_regs *regs)
-{
-        __asm__ __volatile__(
-                ".set push\n\t"
-                ".set noat\n\t"
-#ifdef CONFIG_64BIT
-                "1: dla $1, 1b\n\t"
-                "sd $1, %0\n\t"
-                "sd $29, %1\n\t"
-                "sd $31, %2\n\t"
-#else
-                "1: la $1, 1b\n\t"
-                "sw $1, %0\n\t"
-                "sw $29, %1\n\t"
-                "sw $31, %2\n\t"
-#endif
-                ".set pop\n\t"
-                : "=m" (regs->cp0_epc),
-                "=m" (regs->regs[29]), "=m" (regs->regs[31])
-                : : "memory");
-}
-
 void show_stack(struct task_struct *task, unsigned long *sp)
 {
         struct pt_regs regs;
@@ -206,11 +180,6 @@ void dump_stack(void)
 {
         struct pt_regs regs;
 
-        /*
-         * Remove any garbage that may be in regs (specially func
-         * addresses) to avoid show_raw_backtrace() to report them
-         */
-        memset(&regs, 0, sizeof(regs));
         prepare_frametrace(&regs);
         show_backtrace(current, &regs);
 }