[PATCH] ftrace/x86: Use kernel identity mapping only when CONFIG_DEBUG_RODATA enabled

[Petr Mladek]

This is just a tiny optimization. The remapping is not needed when the
kernel text mapping is read write all the time.

Suggested-by: Jan Beulich <jbeulich@xxxxxxxx>
Signed-off-by: Petr Mladek <pmladek@xxxxxxx>
---
 arch/x86/kernel/ftrace.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index cbc4a91b131e..a7a517bb793e 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -79,6 +79,7 @@ within(unsigned long addr, unsigned long start, unsigned long end)
 
 static unsigned long text_ip_addr(unsigned long ip)
 {
+#ifdef CONFIG_DEBUG_RODATA
 	/*
 	 * On x86_64, kernel text mappings are mapped read-only with
 	 * CONFIG_DEBUG_RODATA. So we use the kernel identity mapping instead
@@ -89,7 +90,7 @@ static unsigned long text_ip_addr(unsigned long ip)
 	 */
 	if (within(ip, (unsigned long)_text, (unsigned long)_etext))
 		ip = (unsigned long)__va(__pa_symbol(ip));
-
+#endif
 	return ip;
 }
 
-- 
1.8.4

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