sh: stack debugging support.

This adds a DEBUG_STACK_USAGE and DEBUG_STACKOVERFLOW for SH.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Paul Mundt 2006-09-27 18:20:16 +09:00
parent 7a440c950e
commit d153ea88dc
6 changed files with 52 additions and 13 deletions

View File

@ -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

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@ -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

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@ -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

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@ -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);

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@ -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

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@ -29,6 +29,8 @@ struct thread_info {
#endif
#define PREEMPT_ACTIVE 0x10000000
#define THREAD_SIZE (PAGE_SIZE * 2)
#define STACK_WARN (THREAD_SIZE / 8)
/*
* macros/functions for gaining access to the thread information structure
@ -50,8 +52,6 @@ struct thread_info {
#define init_thread_info (init_thread_union.thread_info)
#define init_stack (init_thread_union.stack)
#define THREAD_SIZE (2*PAGE_SIZE)
/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
@ -73,8 +73,12 @@ static inline struct thread_info *current_thread_info(void)
}
/* thread information allocation */
#define alloc_thread_info(ti) ((struct thread_info *) __get_free_pages(GFP_KERNEL,1))
#define free_thread_info(ti) free_pages((unsigned long) (ti), 1)
#ifdef CONFIG_DEBUG_STACK_USAGE
#define alloc_thread_info(ti) kzalloc(THREAD_SIZE, GFP_KERNEL)
#else
#define alloc_thread_info(ti) kmalloc(THREAD_SIZE, GFP_KERNEL)
#endif
#define free_thread_info(ti) kfree(ti)
#else /* !__ASSEMBLY__ */