Commit a448276c authored by Steven Rostedt (VMware)'s avatar Steven Rostedt (VMware)
Browse files

arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack 



The structure of the ret_stack array on the task struct is going to
change, and accessing it directly via the curr_ret_stack index will no
longer give the ret_stack entry that holds the return address. To access
that, architectures must now use ftrace_graph_get_ret_stack() to get the
associated ret_stack that matches the saved return address.

Cc: linux-arm-kernel@lists.infradead.org
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent cec8d0e7

arch/arm64/kernel/perf_callchain.c

+1 −1
Original line number Diff line number Diff line
@@ -164,7 +164,7 @@ void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, 
	frame.fp = regs->regs[29];

	frame.pc = regs->pc;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = current->curr_ret_stack;

	frame.graph = 0;

#endif



	walk_stackframe(current, &frame, callchain_trace, entry);

arch/arm64/kernel/process.c

+1 −1
Original line number Diff line number Diff line
@@ -459,7 +459,7 @@ unsigned long get_wchan(struct task_struct *p) 
	frame.fp = thread_saved_fp(p);

	frame.pc = thread_saved_pc(p);

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = p->curr_ret_stack;

	frame.graph = 0;

#endif

	do {

		if (unwind_frame(p, &frame))

arch/arm64/kernel/return_address.c

+1 −1
Original line number Diff line number Diff line
@@ -44,7 +44,7 @@ void *return_address(unsigned int level) 
	frame.fp = (unsigned long)__builtin_frame_address(0);

	frame.pc = (unsigned long)return_address; /* dummy */

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = current->curr_ret_stack;

	frame.graph = 0;

#endif



	walk_stackframe(current, &frame, save_return_addr, &data);

arch/arm64/kernel/stacktrace.c

+7 −5
Original line number Diff line number Diff line
@@ -59,15 +59,17 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) 
#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	if (tsk->ret_stack &&

			(frame->pc == (unsigned long)return_to_handler)) {

		if (WARN_ON_ONCE(frame->graph == -1))

			return -EINVAL;

		struct ftrace_ret_stack *ret_stack;

		/*

		 * This is a case where function graph tracer has

		 * modified a return address (LR) in a stack frame

		 * to hook a function return.

		 * So replace it to an original value.

		 */

		frame->pc = tsk->ret_stack[frame->graph--].ret;

		ret_stack = ftrace_graph_get_ret_stack(tsk, frame->graph++);

		if (WARN_ON_ONCE(!ret_stack))

			return -EINVAL;

		frame->pc = ret_stack->ret;

	}

#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
@@ -134,7 +136,7 @@ void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) 
	frame.fp = regs->regs[29];

	frame.pc = regs->pc;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = current->curr_ret_stack;

	frame.graph = 0;

#endif



	walk_stackframe(current, &frame, save_trace, &data);
@@ -165,7 +167,7 @@ static noinline void __save_stack_trace(struct task_struct *tsk, 
		frame.pc = (unsigned long)__save_stack_trace;

	}

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = tsk->curr_ret_stack;

	frame.graph = 0;

#endif



	walk_stackframe(tsk, &frame, save_trace, &data);

arch/arm64/kernel/time.c

+1 −1
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ unsigned long profile_pc(struct pt_regs *regs) 
	frame.fp = regs->regs[29];

	frame.pc = regs->pc;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = current->curr_ret_stack;

	frame.graph = 0;

#endif

	do {

		int ret = unwind_frame(NULL, &frame);