Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7d56c65a authored by Anton Blanchard's avatar Anton Blanchard Committed by Michael Ellerman
Browse files

powerpc/ftrace: Remove mod_return_to_handler 



mod_return_to_handler is the same as return_to_handler, except
it handles the change of the TOC (r2). Add this into
return_to_handler and remove mod_return_to_handler.

Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 6e4c632c

arch/powerpc/kernel/entry_64.S

+1 −23
Original line number Diff line number Diff line
@@ -1240,28 +1240,6 @@ _GLOBAL(ftrace_graph_caller) 
	blr



_GLOBAL(return_to_handler)

	/* need to save return values */

	std	r4,  -24(r1)

	std	r3,  -16(r1)

	std	r31, -8(r1)

	mr	r31, r1

	stdu	r1, -112(r1)



	bl	ftrace_return_to_handler

	nop



	/* return value has real return address */

	mtlr	r3



	ld	r1, 0(r1)

	ld	r4,  -24(r1)

	ld	r3,  -16(r1)

	ld	r31, -8(r1)



	/* Jump back to real return address */

	blr



_GLOBAL(mod_return_to_handler)

	/* need to save return values */

	std	r4,  -32(r1)

	std	r3,  -24(r1)
@@ -1272,7 +1250,7 @@ _GLOBAL(mod_return_to_handler) 
	stdu	r1, -112(r1)



	/*

	 * We are in a module using the module's TOC.

	 * We might be called from a module.

	 * Switch to our TOC to run inside the core kernel.

	 */

	ld	r2, PACATOC(r13)

arch/powerpc/kernel/ftrace.c

+2 −12
Original line number Diff line number Diff line
@@ -510,10 +510,6 @@ int ftrace_disable_ftrace_graph_caller(void) 
}

#endif /* CONFIG_DYNAMIC_FTRACE */



#ifdef CONFIG_PPC64

extern void mod_return_to_handler(void);

#endif



/*

 * Hook the return address and push it in the stack of return addrs

 * in current thread info.
@@ -523,7 +519,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr) 
	unsigned long old;

	int faulted;

	struct ftrace_graph_ent trace;

	unsigned long return_hooker = (unsigned long)&return_to_handler;

	unsigned long return_hooker;



	if (unlikely(ftrace_graph_is_dead()))

		return;
@@ -531,13 +527,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr) 
	if (unlikely(atomic_read(&current->tracing_graph_pause)))

		return;



#ifdef CONFIG_PPC64

	/* non core kernel code needs to save and restore the TOC */

	if (REGION_ID(self_addr) != KERNEL_REGION_ID)

		return_hooker = (unsigned long)&mod_return_to_handler;

#endif



	return_hooker = ppc_function_entry((void *)return_hooker);

	return_hooker = ppc_function_entry(return_to_handler);



	/*

	 * Protect against fault, even if it shouldn't

arch/powerpc/kernel/process.c

+1 −8
Original line number Diff line number Diff line
@@ -1527,13 +1527,6 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) 
	int curr_frame = current->curr_ret_stack;

	extern void return_to_handler(void);

	unsigned long rth = (unsigned long)return_to_handler;

	unsigned long mrth = -1;

#ifdef CONFIG_PPC64

	extern void mod_return_to_handler(void);

	rth = *(unsigned long *)rth;

	mrth = (unsigned long)mod_return_to_handler;

	mrth = *(unsigned long *)mrth;

#endif

#endif



	sp = (unsigned long) stack;
@@ -1558,7 +1551,7 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) 
		if (!firstframe || ip != lr) {

			printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip);

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

			if ((ip == rth || ip == mrth) && curr_frame >= 0) {

			if ((ip == rth) && curr_frame >= 0) {

				printk(" (%pS)",

				       (void *)current->ret_stack[curr_frame].ret);

				curr_frame--;