Commit d153ea88 authored by Paul Mundt's avatar Paul Mundt
Browse files

sh: stack debugging support. 



This adds a DEBUG_STACK_USAGE and DEBUG_STACKOVERFLOW for SH.

Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 7a440c95

arch/sh/Kconfig.debug

+16 −0
Original line number Diff line number Diff line
@@ -30,6 +30,22 @@ config EARLY_PRINTK 
	  when the kernel may crash or hang before the serial console is

	  initialised. If unsure, say N.



config DEBUG_STACKOVERFLOW

	bool "Check for stack overflows"

	depends on DEBUG_KERNEL

	help

	  This option will cause messages to be printed if free stack space

	  drops below a certain limit.



config DEBUG_STACK_USAGE

	bool "Stack utilization instrumentation"

	depends on DEBUG_KERNEL

	help

	  Enables the display of the minimum amount of free stack which each

	  task has ever had available in the sysrq-T and sysrq-P debug output.



	  This option will slow down process creation somewhat.



config KGDB

	bool "Include KGDB kernel debugger"

	select FRAME_POINTER

arch/sh/kernel/head.S

+3 −1
Original line number Diff line number Diff line
@@ -11,6 +11,8 @@ 
 * Head.S contains the SH exception handlers and startup code.

 */

#include <linux/linkage.h>

#include <asm/thread_info.h>

#include <asm/page.h>



#ifdef CONFIG_CPU_SH4A

#define SYNCO()		synco
@@ -95,7 +97,7 @@ ENTRY(_stext) 


	.balign 4

1:	.long	0x400080F0		! MD=1, RB=0, BL=0, FD=1, IMASK=0xF

2:	.long	init_thread_union+8192

2:	.long	init_thread_union+THREAD_SIZE

3:	.long	__bss_start

4:	.long	_end

5:	.long	start_kernel

arch/sh/kernel/irq.c

+16 −1
Original line number Diff line number Diff line
@@ -60,7 +60,6 @@ int show_interrupts(struct seq_file *p, void *v) 
}

#endif





asmlinkage int do_IRQ(unsigned long r4, unsigned long r5,

		      unsigned long r6, unsigned long r7,

		      struct pt_regs regs)
@@ -69,6 +68,22 @@ asmlinkage int do_IRQ(unsigned long r4, unsigned long r5, 


	irq_enter();



#ifdef CONFIG_DEBUG_STACKOVERFLOW

	/* Debugging check for stack overflow: is there less than 1KB free? */

	{

		long sp;



		__asm__ __volatile__ ("and r15, %0" :

					"=r" (sp) : "0" (THREAD_SIZE - 1));



		if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {

			printk("do_IRQ: stack overflow: %ld\n",

			       sp - sizeof(struct thread_info));

			dump_stack();

		}

	}

#endif



#ifdef CONFIG_CPU_HAS_INTEVT

	__asm__ __volatile__ (

#ifdef CONFIG_CPU_HAS_SR_RB

arch/sh/kernel/vmlinux.lds.S

+8 −6
Original line number Diff line number Diff line
@@ -2,6 +2,8 @@ 
 * ld script to make SuperH Linux kernel

 * Written by Niibe Yutaka

 */

#include <asm/thread_info.h>

#include <asm/page.h>

#include <asm-generic/vmlinux.lds.h>



#ifdef CONFIG_CPU_LITTLE_ENDIAN
@@ -40,16 +42,16 @@ SECTIONS 
	*(.data)



 	 /* Align the initial ramdisk image (INITRD) on page boundaries. */

 	 . = ALIGN(4096);

 	 . = ALIGN(PAGE_SIZE);

 	 __rd_start = .;

 	 *(.initrd)

 	 . = ALIGN(4096);

 	 . = ALIGN(PAGE_SIZE);

 	 __rd_end = .;



	CONSTRUCTORS

	}



  . = ALIGN(4096);

  . = ALIGN(PAGE_SIZE);

  .data.page_aligned : { *(.data.idt) }



  . = ALIGN(32);
@@ -60,10 +62,10 @@ SECTIONS 


  _edata = .;			/* End of data section */



  . = ALIGN(8192);		/* init_task */

  . = ALIGN(THREAD_SIZE);		/* init_task */

  .data.init_task : { *(.data.init_task) }



  . = ALIGN(4096);		/* Init code and data */

  . = ALIGN(PAGE_SIZE);		/* Init code and data */

  __init_begin = .;

  _sinittext = .;

  .init.text : { *(.init.text) }
@@ -94,7 +96,7 @@ SECTIONS 
  __machvec_start = .;

  .init.machvec : { *(.init.machvec) }

  __machvec_end = .;

  . = ALIGN(4096);

  . = ALIGN(PAGE_SIZE);

  __init_end = .;



  . = ALIGN(4);

include/asm-sh/page.h

+1 −1
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ 


/* PAGE_SHIFT determines the page size */

#define PAGE_SHIFT	12

#define PAGE_SIZE	(1UL << PAGE_SHIFT)

#define PAGE_SIZE	(1 << PAGE_SHIFT)

#define PAGE_MASK	(~(PAGE_SIZE-1))

#define PTE_MASK	PAGE_MASK