linux-kernel - [PATCH 4/4] riscv: remove the switch statement in do_trap

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Date:   Mon, 23 Sep 2019 08:45:17 +0800
From:   Vincent Chen <vincent.chen@...ive.com>
To:     linux-riscv@...ts.infradead.org
Cc:     paul.walmsley@...ive.com, palmer@...ive.com, aou@...s.berkeley.edu,
        linux-kernel@...r.kernel.org, vincent.chen@...ive.com
Subject: [PATCH 4/4] riscv: remove the switch statement in do_trap_break()

To make the code more straightforward, replacing the switch statement
with if statement.

Suggested-by: Paul Walmsley <paul.walmsley@...ive.com>
Signed-off-by: Vincent Chen <vincent.chen@...ive.com>
---
 arch/riscv/kernel/traps.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index dd13bc90aeb6..1ac75f7d0bff 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -124,23 +124,24 @@ static inline unsigned long get_break_insn_length(unsigned long pc)
 
 asmlinkage void do_trap_break(struct pt_regs *regs)
 {
-	if (!user_mode(regs)) {
+	if (user_mode(regs)) {
+		force_sig_fault(SIGTRAP, TRAP_BRKPT,
+				(void __user *)(regs->sepc));
+		return;
+	}
+#ifdef CONFIG_GENERIC_BUG
+	{
 		enum bug_trap_type type;
 
 		type = report_bug(regs->sepc, regs);
-		switch (type) {
-#ifdef CONFIG_GENERIC_BUG
-		case BUG_TRAP_TYPE_WARN:
+		if (type == BUG_TRAP_TYPE_WARN) {
 			regs->sepc += get_break_insn_length(regs->sepc);
 			return;
-		case BUG_TRAP_TYPE_BUG:
-#endif /* CONFIG_GENERIC_BUG */
-		default:
-			die(regs, "Kernel BUG");
 		}
-	} else
-		force_sig_fault(SIGTRAP, TRAP_BRKPT,
-				(void __user *)(regs->sepc));
+	}
+#endif /* CONFIG_GENERIC_BUG */
+
+	die(regs, "Kernel BUG");
 }
 
 #ifdef CONFIG_GENERIC_BUG
-- 
2.7.4