Commit d996d505 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/ftrace: Refactor prepare_ftrace_return() 



When we have CONFIG_DYNAMIC_FTRACE_WITH_ARGS,
prepare_ftrace_return() is called by ftrace_graph_func()
otherwise prepare_ftrace_return() is called from assembly.

Refactor prepare_ftrace_return() into a static
__prepare_ftrace_return() that will be called by both
prepare_ftrace_return() and ftrace_graph_func().

It will allow GCC to fold __prepare_ftrace_return() inside
ftrace_graph_func().

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0d42deafe353980c66cf19d3132638c05ba9f4a9.1652074503.git.christophe.leroy@csgroup.eu
parent 804c0a16

arch/powerpc/kernel/trace/ftrace.c

+9 −3
Original line number Diff line number Diff line
@@ -939,8 +939,8 @@ int ftrace_disable_ftrace_graph_caller(void) 
 * Hook the return address and push it in the stack of return addrs

 * in current thread info. Return the address we want to divert to.

 */

unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,

						unsigned long sp)

static unsigned long

__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp)

{

	unsigned long return_hooker;

	int bit;
@@ -969,7 +969,13 @@ unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip, 
void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,

		       struct ftrace_ops *op, struct ftrace_regs *fregs)

{

	fregs->regs.link = prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]);

	fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]);

}

#else

unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,

				    unsigned long sp)

{

	return __prepare_ftrace_return(parent, ip, sp);

}

#endif

#endif /* CONFIG_FUNCTION_GRAPH_TRACER */