diff mbox series

[v5,07/17] powerpc/ftrace: Skip instruction patching if the instructions are the same

Message ID 20240915205648.830121-8-hbathini@linux.ibm.com (mailing list archive)
State New
Headers show
Series powerpc: Core ftrace rework, support for ftrace direct and bpf trampolines | expand

Commit Message

Hari Bathini Sept. 15, 2024, 8:56 p.m. UTC 
From: Naveen N Rao <naveen@kernel.org>

To simplify upcoming changes to ftrace, add a check to skip actual
instruction patching if the old and new instructions are the same. We
still validate that the instruction is what we expect, but don't
actually patch the same instruction again.

Signed-off-by: Naveen N Rao <naveen@kernel.org>
---
 arch/powerpc/kernel/trace/ftrace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index fe0546fbac8e..719517265d39 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -82,7 +82,7 @@  static inline int ftrace_modify_code(unsigned long ip, ppc_inst_t old, ppc_inst_
 {
 	int ret = ftrace_validate_inst(ip, old);
 
-	if (!ret)
+	if (!ret && !ppc_inst_equal(old, new))
 		ret = patch_instruction((u32 *)ip, new);
 
 	return ret;