Re: [PATCH] arm64: stacktrace: Factor out some common code info on_stack()
From: Will Deacon
Date: Thu May 07 2020 - 09:52:21 EST
On Thu, May 07, 2020 at 05:28:19PM +0800, Yunfeng Ye wrote:
> diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h
> index fdb913cc0bcb..b92bef2fb6cd 100644
> --- a/arch/arm64/include/asm/stacktrace.h
> +++ b/arch/arm64/include/asm/stacktrace.h
> @@ -69,27 +69,40 @@ extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk,
>
> DECLARE_PER_CPU(unsigned long *, irq_stack_ptr);
>
> -static inline bool on_irq_stack(unsigned long sp,
> +static inline bool on_stack(unsigned long sp, unsigned long low,
> + unsigned long high, enum stack_type type,
> struct stack_info *info)
> {
> - unsigned long low = (unsigned long)raw_cpu_read(irq_stack_ptr);
> - unsigned long high = low + IRQ_STACK_SIZE;
> -
> - if (!low)
> - return false;
> -
> if (sp < low || sp >= high)
> return false;
>
> if (info) {
> info->low = low;
> info->high = high;
> - info->type = STACK_TYPE_IRQ;
> + info->type = type;
> }
> -
> return true;
> }
>
> +static inline bool on_valid_stack(unsigned long sp, unsigned long low,
> + unsigned long high, enum stack_type type,
> + struct stack_info *info)
> +{
> + if (!low)
> + return false;
> +
> + return on_stack(sp, low, high, type, info);
> +}
Do we need this as distinct from on_stack()? Afaict, 'low' is never
going to be NULL for the on_stack() callers, so I suggest just having
on_stack() check 'low' and getting everybody to call that instead.
Make sense?
Will