stacktrace.h

Go to the documentation of this file.

#ifndef _ASM_STACKTRACE_H
#define _ASM_STACKTRACE_H

#include <asm/ptrace.h>

#ifdef CONFIG_KALLSYMS
extern int raw_show_trace;
extern unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
                  unsigned long pc, unsigned long *ra);
extern unsigned long unwind_stack_by_address(unsigned long stack_page,
                         unsigned long *sp,
                         unsigned long pc,
                         unsigned long *ra);
#else
#define raw_show_trace 1
static inline unsigned long unwind_stack(struct task_struct *task,
    unsigned long *sp, unsigned long pc, unsigned long *ra)
{
    return 0;
}
#endif

static __always_inline void prepare_frametrace(struct pt_regs *regs)
{
#ifndef CONFIG_KALLSYMS
    /*
     * Remove any garbage that may be in regs (specially func
     * addresses) to avoid show_raw_backtrace() to report them
     */
    memset(regs, 0, sizeof(*regs));
#endif
    __asm__ __volatile__(
        ".set push\n\t"
        ".set noat\n\t"
#ifdef CONFIG_64BIT
        "1: dla $1, 1b\n\t"
        "sd $1, %0\n\t"
        "sd $29, %1\n\t"
        "sd $31, %2\n\t"
#else
        "1: la $1, 1b\n\t"
        "sw $1, %0\n\t"
        "sw $29, %1\n\t"
        "sw $31, %2\n\t"
#endif
        ".set pop\n\t"
        : "=m" (regs->cp0_epc),
        "=m" (regs->regs[29]), "=m" (regs->regs[31])
        : : "memory");
}

#endif /* _ASM_STACKTRACE_H */