From 4eb4ff5a368c7ebc74b0c8813ac924a1b347ac63 Mon Sep 17 00:00:00 2001
From: Wu Zhangjin <wuzhangjin@gmail.com>
Date: Fri, 20 Nov 2009 20:34:35 +0800
Subject: [PATCH] --- yaml --- r: 177903 b: refs/heads/master c:
 e17ff5fec65a0213416efbe7ceae5f2f9887dda2 h: refs/heads/master i:   177901:
 e30bf6cd1ab206e6be78ea7883886fed8936861e   177899:
 686f1b60f20d3968dfe19df48fc6f27cea466d02   177895:
 43f8299fce2de31243752a6dbc4671dceb0ee8d2   177887:
 0ae557082266ec709d1e93a29a3675a19b166ac1 v: v3

---
 [refs]                          |  2 +-
 trunk/arch/mips/kernel/ftrace.c | 21 +++++++++++++++++++++
 trunk/arch/mips/kernel/mcount.S | 14 ++++++++++++--
 3 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index ca5aa4629664..e46b88cd17c0 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 29c5d3462f7c8f17bb9e0a29f0a299036468074d
+refs/heads/master: e17ff5fec65a0213416efbe7ceae5f2f9887dda2
diff --git a/trunk/arch/mips/kernel/ftrace.c b/trunk/arch/mips/kernel/ftrace.c
index 65a3f8a89927..e981a497c98f 100644
--- a/trunk/arch/mips/kernel/ftrace.c
+++ b/trunk/arch/mips/kernel/ftrace.c
@@ -115,6 +115,27 @@ int __init ftrace_dyn_arch_init(void *data)
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+extern void ftrace_graph_call(void);
+#define JMP	0x08000000	/* jump to target directly */
+#define CALL_FTRACE_GRAPH_CALLER \
+	jump_insn_encode(JMP, (unsigned long)(&ftrace_graph_caller))
+#define FTRACE_GRAPH_CALL_IP	((unsigned long)(&ftrace_graph_call))
+
+int ftrace_enable_ftrace_graph_caller(void)
+{
+	return ftrace_modify_code(FTRACE_GRAPH_CALL_IP,
+				  CALL_FTRACE_GRAPH_CALLER);
+}
+
+int ftrace_disable_ftrace_graph_caller(void)
+{
+	return ftrace_modify_code(FTRACE_GRAPH_CALL_IP, ftrace_nop);
+}
+
+#endif				/* !CONFIG_DYNAMIC_FTRACE */
+
 #define S_RA_SP	(0xafbf << 16)	/* s{d,w} ra, offset(sp) */
 #define S_R_SP	(0xafb0 << 16)  /* s{d,w} R, offset(sp) */
 #define OFFSET_MASK	0xffff	/* stack offset range: 0 ~ PT_SIZE */
diff --git a/trunk/arch/mips/kernel/mcount.S b/trunk/arch/mips/kernel/mcount.S
index b50e38d828c4..98d469032506 100644
--- a/trunk/arch/mips/kernel/mcount.S
+++ b/trunk/arch/mips/kernel/mcount.S
@@ -77,6 +77,13 @@ ftrace_call:
 	nop	/* a placeholder for the call to a real tracing function */
 	 move	a1, AT		/* arg2: the caller's next ip, parent */
 
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+	.globl ftrace_graph_call
+ftrace_graph_call:
+	nop
+	 nop
+#endif
+
 	MCOUNT_RESTORE_REGS
 	.globl ftrace_stub
 ftrace_stub:
@@ -124,10 +131,13 @@ ftrace_stub:
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 
 NESTED(ftrace_graph_caller, PT_SIZE, ra)
+#ifdef CONFIG_DYNAMIC_FTRACE
+	PTR_L	a1, PT_R31(sp)	/* load the original ra from the stack */
+#else
 	MCOUNT_SAVE_REGS
-
-	PTR_LA	a0, PT_R1(sp)	/* arg1: &AT -> a0 */
 	move	a1, ra		/* arg2: next ip, selfaddr */
+#endif
+	PTR_LA	a0, PT_R1(sp)	/* arg1: &AT -> a0 */
 	jal	prepare_ftrace_return
 	 move	a2, fp		/* arg3: frame pointer */