[PATCH] process: change from __backtrace to dump_stack in show_regs

[Nicolas Pitre]

On Thu, 25 Aug 2011, Laura Abbott wrote:

> Currently, show_regs calls __backtrace which does
> nothing if CONFIG_FRAME_POINTER is not set. Switch to
> dump_stack which handles both CONFIG_FRAME_POINTER and
> CONFIG_ARM_UNWIND correctly.
> 
> __backtrace is now superseded by dump_stack in general
> and show_regs was the last caller so remove __backtrace
> as well.
> 
> Signed-off-by: Laura Abbott <lauraa at codeaurora.org>

Acked-by: Nicolas Pitre <nicolas.pitre at linaro.org>


> ---
>  arch/arm/include/asm/system.h |    1 -
>  arch/arm/kernel/armksyms.c    |    3 ---
>  arch/arm/kernel/process.c     |    2 +-
>  arch/arm/lib/backtrace.S      |    6 ------
>  4 files changed, 1 insertions(+), 11 deletions(-)
> 
> diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
> index 832888d..4fc2edd 100644
> --- a/arch/arm/include/asm/system.h
> +++ b/arch/arm/include/asm/system.h
> @@ -97,7 +97,6 @@ void hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int,
>  #define xchg(ptr,x) \
>  	((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
>  
> -extern asmlinkage void __backtrace(void);
>  extern asmlinkage void c_backtrace(unsigned long fp, int pmode);
>  
>  struct mm_struct;
> diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c
> index aeef960..8e3c6f1 100644
> --- a/arch/arm/kernel/armksyms.c
> +++ b/arch/arm/kernel/armksyms.c
> @@ -49,9 +49,6 @@ extern void __aeabi_ulcmp(void);
>  
>  extern void fpundefinstr(void);
>  
> -
> -EXPORT_SYMBOL(__backtrace);
> -
>  	/* platform dependent support */
>  EXPORT_SYMBOL(__udelay);
>  EXPORT_SYMBOL(__const_udelay);
> diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
> index 1a347f4..fd08140 100644
> --- a/arch/arm/kernel/process.c
> +++ b/arch/arm/kernel/process.c
> @@ -319,7 +319,7 @@ void show_regs(struct pt_regs * regs)
>  	printk("\n");
>  	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
>  	__show_regs(regs);
> -	__backtrace();
> +	dump_stack();
>  }
>  
>  ATOMIC_NOTIFIER_HEAD(thread_notify_head);
> diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S
> index a673297..cd07b58 100644
> --- a/arch/arm/lib/backtrace.S
> +++ b/arch/arm/lib/backtrace.S
> @@ -22,15 +22,10 @@
>  #define mask	r7
>  #define offset	r8
>  
> -ENTRY(__backtrace)
> -		mov	r1, #0x10
> -		mov	r0, fp
> -
>  ENTRY(c_backtrace)
>  
>  #if !defined(CONFIG_FRAME_POINTER) || !defined(CONFIG_PRINTK)
>  		mov	pc, lr
> -ENDPROC(__backtrace)
>  ENDPROC(c_backtrace)
>  #else
>  		stmfd	sp!, {r4 - r8, lr}	@ Save an extra register so we have a location...
> @@ -107,7 +102,6 @@ for_each_frame:	tst	frame, mask		@ Check for address exceptions
>  		mov	r1, frame
>  		bl	printk
>  no_frame:	ldmfd	sp!, {r4 - r8, pc}
> -ENDPROC(__backtrace)
>  ENDPROC(c_backtrace)
>  		
>  		.pushsection __ex_table,"a"
> -- 
> 1.7.3.3
>