Re: [PATCH v12 02/10] arm64: Rename unwinder functions

[Mark Rutland <mark.rutland@arm.com>]

On Mon, Jan 03, 2022 at 10:52:04AM -0600, madvenka@linux.microsoft.com wrote:
> From: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com>
> 
> Rename unwinder functions for consistency and better naming.
> 
> 	- Rename start_backtrace() to unwind_init().
> 	- Rename unwind_frame() to unwind_next().
> 	- Rename walk_stackframe() to unwind().
> 
> Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com>
> Reviewed-by: Mark Brown <broonie@kernel.org>
> Acked-by: Mark Rutland <mark.rutland@arm.com>

For consistency, to replace my prior Acked-by:

Reviewed-by: Mark Rutland <mark.rutland@arm.com>

Mark.

> ---
>  arch/arm64/kernel/stacktrace.c | 32 ++++++++++++++++----------------
>  1 file changed, 16 insertions(+), 16 deletions(-)
> 
> diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
> index 5f5bb35b7b41..b980d96dccfc 100644
> --- a/arch/arm64/kernel/stacktrace.c
> +++ b/arch/arm64/kernel/stacktrace.c
> @@ -33,8 +33,8 @@
>   */
>  
>  
> -static void start_backtrace(struct stackframe *frame, unsigned long fp,
> -			    unsigned long pc)
> +static void unwind_init(struct stackframe *frame, unsigned long fp,
> +			unsigned long pc)
>  {
>  	frame->fp = fp;
>  	frame->pc = pc;
> @@ -45,7 +45,7 @@ static void start_backtrace(struct stackframe *frame, unsigned long fp,
>  	/*
>  	 * Prime the first unwind.
>  	 *
> -	 * In unwind_frame() we'll check that the FP points to a valid stack,
> +	 * In unwind_next() we'll check that the FP points to a valid stack,
>  	 * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be
>  	 * treated as a transition to whichever stack that happens to be. The
>  	 * prev_fp value won't be used, but we set it to 0 such that it is
> @@ -63,8 +63,8 @@ static void start_backtrace(struct stackframe *frame, unsigned long fp,
>   * records (e.g. a cycle), determined based on the location and fp value of A
>   * and the location (but not the fp value) of B.
>   */
> -static int notrace unwind_frame(struct task_struct *tsk,
> -				struct stackframe *frame)
> +static int notrace unwind_next(struct task_struct *tsk,
> +			       struct stackframe *frame)
>  {
>  	unsigned long fp = frame->fp;
>  	struct stack_info info;
> @@ -104,7 +104,7 @@ static int notrace unwind_frame(struct task_struct *tsk,
>  
>  	/*
>  	 * Record this frame record's values and location. The prev_fp and
> -	 * prev_type are only meaningful to the next unwind_frame() invocation.
> +	 * prev_type are only meaningful to the next unwind_next() invocation.
>  	 */
>  	frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp));
>  	frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 8));
> @@ -137,23 +137,23 @@ static int notrace unwind_frame(struct task_struct *tsk,
>  
>  	return 0;
>  }
> -NOKPROBE_SYMBOL(unwind_frame);
> +NOKPROBE_SYMBOL(unwind_next);
>  
> -static void notrace walk_stackframe(struct task_struct *tsk,
> -				    struct stackframe *frame,
> -				    bool (*fn)(void *, unsigned long), void *data)
> +static void notrace unwind(struct task_struct *tsk,
> +			   struct stackframe *frame,
> +			   bool (*fn)(void *, unsigned long), void *data)
>  {
>  	while (1) {
>  		int ret;
>  
>  		if (!fn(data, frame->pc))
>  			break;
> -		ret = unwind_frame(tsk, frame);
> +		ret = unwind_next(tsk, frame);
>  		if (ret < 0)
>  			break;
>  	}
>  }
> -NOKPROBE_SYMBOL(walk_stackframe);
> +NOKPROBE_SYMBOL(unwind);
>  
>  static bool dump_backtrace_entry(void *arg, unsigned long where)
>  {
> @@ -195,14 +195,14 @@ noinline notrace void arch_stack_walk(stack_trace_consume_fn consume_entry,
>  	struct stackframe frame;
>  
>  	if (regs)
> -		start_backtrace(&frame, regs->regs[29], regs->pc);
> +		unwind_init(&frame, regs->regs[29], regs->pc);
>  	else if (task == current)
> -		start_backtrace(&frame,
> +		unwind_init(&frame,
>  				(unsigned long)__builtin_frame_address(1),
>  				(unsigned long)__builtin_return_address(0));
>  	else
> -		start_backtrace(&frame, thread_saved_fp(task),
> +		unwind_init(&frame, thread_saved_fp(task),
>  				thread_saved_pc(task));
>  
> -	walk_stackframe(task, &frame, consume_entry, cookie);
> +	unwind(task, &frame, consume_entry, cookie);
>  }
> -- 
> 2.25.1
>