traps.c

Go to the documentation of this file.

/*
 * Copyright (C) 2007-2009 Michal Simek <[email protected]>
 * Copyright (C) 2007-2009 PetaLogix
 * Copyright (C) 2006 Atmark Techno, Inc.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#include <linux/kernel.h>
#include <linux/kallsyms.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/debug_locks.h>

#include <asm/exceptions.h>
#include <asm/unwind.h>

void trap_init(void)
{
    __enable_hw_exceptions();
}

static unsigned long kstack_depth_to_print; /* 0 == entire stack */

static int __init kstack_setup(char *s)
{
    return !strict_strtoul(s, 0, &kstack_depth_to_print);
}
__setup("kstack=", kstack_setup);

void show_stack(struct task_struct *task, unsigned long *sp)
{
    unsigned long words_to_show;
    u32 fp = (u32) sp;

    if (fp == 0) {
        if (task) {
            fp = ((struct thread_info *)
                (task->stack))->cpu_context.r1;
        } else {
            /* Pick up caller of dump_stack() */
            fp = (u32)&sp - 8;
        }
    }

    words_to_show = (THREAD_SIZE - (fp & (THREAD_SIZE - 1))) >> 2;
    if (kstack_depth_to_print && (words_to_show > kstack_depth_to_print))
        words_to_show = kstack_depth_to_print;

    pr_info("Kernel Stack:\n");

    /*
     * Make the first line an 'odd' size if necessary to get
     * remaining lines to start at an address multiple of 0x10
     */
    if (fp & 0xF) {
        unsigned long line1_words = (0x10 - (fp & 0xF)) >> 2;
        if (line1_words < words_to_show) {
            print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 32,
                       4, (void *)fp, line1_words << 2, 0);
            fp += line1_words << 2;
            words_to_show -= line1_words;
        }
    }
    print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 32, 4, (void *)fp,
               words_to_show << 2, 0);
    printk(KERN_INFO "\n\n");

    pr_info("Call Trace:\n");
    microblaze_unwind(task, NULL);
    pr_info("\n");

    if (!task)
        task = current;

    debug_show_held_locks(task);
}

void dump_stack(void)
{
    show_stack(NULL, NULL);
}
EXPORT_SYMBOL(dump_stack);