ftrace: Cleanup ftrace_dyn_arch_init()

Most of ARCHs use empty ftrace_dyn_arch_init(), introduce a weak common
ftrace_dyn_arch_init() to cleanup them.

Link: https://lkml.kernel.org/r/20210909090216.1955240-1-o451686892@gmail.com

Acked-by: Heiko Carstens <hca@linux.ibm.com> (s390)
Acked-by: Helge Deller <deller@gmx.de> (parisc)
Signed-off-by: Weizhao Ouyang <o451686892@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

arch/arm/kernel/ftrace.c

@@ -193,11 +193,6 @@ int ftrace_make_nop(struct module *mod,
 
 	return ret;
 }
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER

arch/arm64/kernel/ftrace.c

@@ -236,11 +236,6 @@ void arch_ftrace_update_code(int command)
 	command |= FTRACE_MAY_SLEEP;
 	ftrace_modify_all_code(command);
 }
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER

arch/csky/kernel/ftrace.c

@@ -133,11 +133,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 				(unsigned long)func, true, true);
 	return ret;
 }
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

arch/ia64/kernel/ftrace.c

@@ -194,9 +194,3 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 	flush_icache_range(addr, addr + 16);
 	return 0;
 }
-
-/* run from kstop_machine */
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}

arch/microblaze/kernel/ftrace.c

@@ -163,11 +163,6 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 	return ret;
 }
 
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
-
 int ftrace_update_ftrace_func(ftrace_func_t func)
 {
 	unsigned long ip = (unsigned long)(&ftrace_call);

arch/nds32/kernel/ftrace.c

@@ -84,11 +84,6 @@ void _ftrace_caller(unsigned long parent_ip)
 	/* restore all state needed by the compiler epilogue */
 }
 
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
-
 static unsigned long gen_sethi_insn(unsigned long addr)
 {
 	unsigned long opcode = 0x46000000;

arch/parisc/kernel/ftrace.c

@@ -94,11 +94,6 @@ int ftrace_disable_ftrace_graph_caller(void)
 #endif
 
 #ifdef CONFIG_DYNAMIC_FTRACE
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
 int ftrace_update_ftrace_func(ftrace_func_t func)
 {
 	return 0;

arch/riscv/kernel/ftrace.c

@@ -154,11 +154,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 
 	return ret;
 }
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
 #endif
 
 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

arch/s390/kernel/ftrace.c

@@ -262,11 +262,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 	return 0;
 }
 
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
-
 void arch_ftrace_update_code(int command)
 {
 	if (ftrace_shared_hotpatch_trampoline(NULL))

arch/sh/kernel/ftrace.c

@@ -252,11 +252,6 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 
 	return ftrace_modify_code(rec->ip, old, new);
 }
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER

arch/sparc/kernel/ftrace.c

@@ -82,11 +82,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 	new = ftrace_call_replace(ip, (unsigned long)func);
 	return ftrace_modify_code(ip, old, new);
 }
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
 #endif
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER

arch/x86/kernel/ftrace.c

@@ -252,11 +252,6 @@ void arch_ftrace_update_code(int command)
 	ftrace_modify_all_code(command);
 }
 
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
-
 /* Currently only x86_64 supports dynamic trampolines */
 #ifdef CONFIG_X86_64
 

kernel/trace/ftrace.c

@@ -6847,6 +6847,11 @@ void __init ftrace_free_init_mem(void)
 	ftrace_free_mem(NULL, start, end);
 }
 
+int __init __weak ftrace_dyn_arch_init(void)
+{
+	return 0;
+}
+
 void __init ftrace_init(void)
 {
 	extern unsigned long __start_mcount_loc[];