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From:   Zong Li <zong.li@sifive.com>
To:     paul.walmsley@sifive.com, palmer@dabbelt.com, rostedt@goodmis.org,
        anup@brainfault.org, linux-kernel@vger.kernel.org,
        linux-riscv@lists.infradead.org
Cc:     Zong Li <zong.li@sifive.com>
Subject: [PATCH 1/2] riscv: ftrace: correct the condition logic in function graph tracer
Date:   Mon, 23 Dec 2019 16:46:13 +0800
Message-Id: <20191223084614.67126-2-zong.li@sifive.com>
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The condition should be logical NOT to assign the hook address to parent
address. Because the return value 0 of function_graph_enter upon
success.

Fixes: e949b6db51dc (riscv/function_graph: Simplify with function_graph_enter())

Signed-off-by: Zong Li <zong.li@sifive.com>
---
 arch/riscv/kernel/ftrace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c
index b94d8db5ddcc..c40fdcdeb950 100644
--- a/arch/riscv/kernel/ftrace.c
+++ b/arch/riscv/kernel/ftrace.c
@@ -142,7 +142,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
 	 */
 	old = *parent;
 
-	if (function_graph_enter(old, self_addr, frame_pointer, parent))
+	if (!function_graph_enter(old, self_addr, frame_pointer, parent))
 		*parent = return_hooker;
 }
 
-- 
2.24.1