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

Commit f3dcbe67 authored by Dave Martin's avatar Dave Martin Committed by Will Deacon
Browse files

arm64: stacktrace: Factor out backtrace initialisation 



Some common code is required by each stacktrace user to initialise
struct stackframe before the first call to unwind_frame().

In preparation for adding to the common code, this patch factors it
out into a separate function start_backtrace(), and modifies the
stacktrace callers appropriately.

No functional change.

Signed-off-by: default avatarDave Martin <dave.martin@arm.com>
[Mark: drop tsk argument, update more callsites]
Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
Reviewed-by: default avatarJames Morse <james.morse@arm.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 8caa6e2b

arch/arm64/include/asm/stacktrace.h

+10 −0
Original line number Diff line number Diff line
@@ -131,4 +131,14 @@ static inline bool on_accessible_stack(const struct task_struct *tsk, 
	return false;

}



static inline void start_backtrace(struct stackframe *frame,

				   unsigned long fp, unsigned long pc)

{

	frame->fp = fp;

	frame->pc = pc;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame->graph = 0;

#endif

}



#endif	/* __ASM_STACKTRACE_H */

arch/arm64/kernel/perf_callchain.c

+1 −6
Original line number Diff line number Diff line
@@ -154,12 +154,7 @@ void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, 
		return;

	}



	frame.fp = regs->regs[29];

	frame.pc = regs->pc;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = 0;

#endif



	start_backtrace(&frame, regs->regs[29], regs->pc);

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

}

arch/arm64/kernel/process.c

+2 −5
Original line number Diff line number Diff line
@@ -498,11 +498,8 @@ unsigned long get_wchan(struct task_struct *p) 
	if (!stack_page)

		return 0;



	frame.fp = thread_saved_fp(p);

	frame.pc = thread_saved_pc(p);

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = 0;

#endif

	start_backtrace(&frame, thread_saved_fp(p), thread_saved_pc(p));



	do {

		if (unwind_frame(p, &frame))

			goto out;

arch/arm64/kernel/return_address.c

+3 −6
Original line number Diff line number Diff line
@@ -38,12 +38,9 @@ void *return_address(unsigned int level) 
	data.level = level + 2;

	data.addr = NULL;



	frame.fp = (unsigned long)__builtin_frame_address(0);

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

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = 0;

#endif



	start_backtrace(&frame,

			(unsigned long)__builtin_frame_address(0),

			(unsigned long)return_address);

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



	if (!data.level)

arch/arm64/kernel/stacktrace.c

+6 −13
Original line number Diff line number Diff line
@@ -122,12 +122,7 @@ void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) 
	data.skip = trace->skip;

	data.no_sched_functions = 0;



	frame.fp = regs->regs[29];

	frame.pc = regs->pc;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = 0;

#endif



	start_backtrace(&frame, regs->regs[29], regs->pc);

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

}

EXPORT_SYMBOL_GPL(save_stack_trace_regs);
@@ -146,17 +141,15 @@ static noinline void __save_stack_trace(struct task_struct *tsk, 
	data.no_sched_functions = nosched;



	if (tsk != current) {

		frame.fp = thread_saved_fp(tsk);

		frame.pc = thread_saved_pc(tsk);

		start_backtrace(&frame, thread_saved_fp(tsk),

				thread_saved_pc(tsk));

	} else {

		/* We don't want this function nor the caller */

		data.skip += 2;

		frame.fp = (unsigned long)__builtin_frame_address(0);

		frame.pc = (unsigned long)__save_stack_trace;

		start_backtrace(&frame,

				(unsigned long)__builtin_frame_address(0),

				(unsigned long)__save_stack_trace);

	}

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	frame.graph = 0;

#endif



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