[PATCH v2 3/3] riscv/ftrace: cleanup ftrace_caller and ftrace_regs_caller

[Song Shuai]

ftrace_caller and ftrace_regs_caller save their regs with the respective
option of SAVE_ALL, then call the tracing function, especially graph_ops's
ftrace_graph_func. So the ftrace_graph_[regs]_call labels aren't needed
anymore if FTRACE_WITH_REGS is defined.

If FTRACE_WITH_REGS isn't defined, the !FTRACE_WITH_REGS version
ftrace_caller remains with the ftrace_graph_call. So the enable/disable
helpers are revised for serving only this ftrace_graph_call.

Signed-off-by: Song Shuai <suagrfillet at gmail.com>
---
 arch/riscv/kernel/ftrace.c     | 19 ++----------------
 arch/riscv/kernel/mcount-dyn.S | 35 +++++++++++++++-------------------
 2 files changed, 17 insertions(+), 37 deletions(-)

diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c
index 148a5480076b..2f0bcedc6a2d 100644
--- a/arch/riscv/kernel/ftrace.c
+++ b/arch/riscv/kernel/ftrace.c
@@ -211,30 +211,15 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */
 
 extern void ftrace_graph_call(void);
-extern void ftrace_graph_regs_call(void);
 int ftrace_enable_ftrace_graph_caller(void)
 {
-	int ret;
-
-	ret = __ftrace_modify_call((unsigned long)&ftrace_graph_call,
-				    (unsigned long)&prepare_ftrace_return, true);
-	if (ret)
-		return ret;
-
-	return __ftrace_modify_call((unsigned long)&ftrace_graph_regs_call,
+	return  __ftrace_modify_call((unsigned long)&ftrace_graph_call,
 				    (unsigned long)&prepare_ftrace_return, true);
 }
 
 int ftrace_disable_ftrace_graph_caller(void)
 {
-	int ret;
-
-	ret = __ftrace_modify_call((unsigned long)&ftrace_graph_call,
-				    (unsigned long)&prepare_ftrace_return, false);
-	if (ret)
-		return ret;
-
-	return __ftrace_modify_call((unsigned long)&ftrace_graph_regs_call,
+	return  __ftrace_modify_call((unsigned long)&ftrace_graph_call,
 				    (unsigned long)&prepare_ftrace_return, false);
 }
 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */
diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S
index 2f0a280bd7a0..9e4097c6793d 100644
--- a/arch/riscv/kernel/mcount-dyn.S
+++ b/arch/riscv/kernel/mcount-dyn.S
@@ -215,6 +215,7 @@
 	.endm
 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */
 
+#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS
 ENTRY(ftrace_caller)
 	SAVE_ABI
 
@@ -243,33 +244,27 @@ ftrace_graph_call:
 	ret
 ENDPROC(ftrace_caller)
 
-#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */
 ENTRY(ftrace_regs_caller)
-	SAVE_ALL
-
-	addi	a0, ra, -FENTRY_RA_OFFSET
-	la	a1, function_trace_op
-	REG_L	a2, 0(a1)
-	REG_L	a1, PT_SIZE_ON_STACK(sp)
-	mv	a3, sp
+	SAVE_ALL 1
 
 ftrace_regs_call:
 	.global ftrace_regs_call
 	call	ftrace_stub
 
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-	addi	a0, sp, PT_RA
-	REG_L	a1, PT_EPC(sp)
-	addi	a1, a1, -FENTRY_RA_OFFSET
-#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
-	mv	a2, s0
-#endif
-ftrace_graph_regs_call:
-	.global ftrace_graph_regs_call
-	call	ftrace_stub
-#endif
 
-	RESTORE_ALL
+	RESTORE_ALL 1
 	ret
 ENDPROC(ftrace_regs_caller)
+
+ENTRY(ftrace_caller)
+	SAVE_ALL 0
+
+ftrace_call:
+	.global ftrace_call
+	call	ftrace_stub
+
+	RESTORE_ALL 0
+	ret
+ENDPROC(ftrace_caller)
 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */
-- 
2.20.1