[PATCH v2 4/6] riscv/ftrace: Add ARCH_SUPPORTS_FTRACE_OPS support

From: Alan Kao
Date: Mon Jan 15 2018 - 01:48:29 EST


Cc: Greentime Hu <greentime@xxxxxxxxxxxxx>
Signed-off-by: Alan Kao <alankao@xxxxxxxxxxxxx>
---
arch/riscv/include/asm/ftrace.h | 1 +
arch/riscv/kernel/mcount-dyn.S | 3 +++
2 files changed, 4 insertions(+)

diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
index acf0c7d001f3..429a6a156645 100644
--- a/arch/riscv/include/asm/ftrace.h
+++ b/arch/riscv/include/asm/ftrace.h
@@ -9,6 +9,7 @@
#define HAVE_FUNCTION_GRAPH_FP_TEST
#endif

+#define ARCH_SUPPORTS_FTRACE_OPS 1
#ifndef __ASSEMBLY__
void _mcount(void);
static inline unsigned long ftrace_call_adjust(unsigned long addr)
diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S
index 64e715d4e180..627478571c7a 100644
--- a/arch/riscv/kernel/mcount-dyn.S
+++ b/arch/riscv/kernel/mcount-dyn.S
@@ -75,9 +75,12 @@ ENTRY(ftrace_caller)
/*
* a0: the address in the caller when calling ftrace_caller
* a1: the caller's return address
+ * a2: the address of global variable function_trace_op
*/
ld a1, -8(s0)
addi a0, ra, -MCOUNT_INSN_SIZE
+ la t5, function_trace_op
+ ld a2, 0(t5)

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
/*
--
2.15.1