MIPS: Tracing: Make ftrace for MIPS work without -fno-omit-frame-pointer
When remove the -fno-omit-frame-pointer, gcc will not save the frame
pointer for us, we need to save one ourselves.
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: zhangfx@lemote.com
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/679/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S
index 98d4690..bdfef2c 100644
--- a/arch/mips/kernel/mcount.S
+++ b/arch/mips/kernel/mcount.S
@@ -139,7 +139,15 @@
#endif
PTR_LA a0, PT_R1(sp) /* arg1: &AT -> a0 */
jal prepare_ftrace_return
+#ifdef CONFIG_FRAME_POINTER
move a2, fp /* arg3: frame pointer */
+#else
+#ifdef CONFIG_64BIT
+ PTR_LA a2, PT_SIZE(sp)
+#else
+ PTR_LA a2, (PT_SIZE+8)(sp)
+#endif
+#endif
MCOUNT_RESTORE_REGS
RETURN_BACK