1 #ifndef _ASM_STACKTRACE_H 2 #define _ASM_STACKTRACE_H 3 4 #include <asm/ptrace.h> 5 6 #ifdef CONFIG_KALLSYMS 7 extern int raw_show_trace; 8 extern unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, 9 unsigned long pc, unsigned long *ra); 10 extern unsigned long unwind_stack_by_address(unsigned long stack_page, 11 unsigned long *sp, 12 unsigned long pc, 13 unsigned long *ra); 14 #else 15 #define raw_show_trace 1 16 static inline unsigned long unwind_stack(struct task_struct *task, 17 unsigned long *sp, unsigned long pc, unsigned long *ra) 18 { 19 return 0; 20 } 21 #endif 22 23 static __always_inline void prepare_frametrace(struct pt_regs *regs) 24 { 25 #ifndef CONFIG_KALLSYMS 26 /* 27 * Remove any garbage that may be in regs (specially func 28 * addresses) to avoid show_raw_backtrace() to report them 29 */ 30 memset(regs, 0, sizeof(*regs)); 31 #endif 32 __asm__ __volatile__( 33 ".set push\n\t" 34 ".set noat\n\t" 35 #ifdef CONFIG_64BIT 36 "1: dla $1, 1b\n\t" 37 "sd $1, %0\n\t" 38 "sd $29, %1\n\t" 39 "sd $31, %2\n\t" 40 #else 41 "1: la $1, 1b\n\t" 42 "sw $1, %0\n\t" 43 "sw $29, %1\n\t" 44 "sw $31, %2\n\t" 45 #endif 46 ".set pop\n\t" 47 : "=m" (regs->cp0_epc), 48 "=m" (regs->regs[29]), "=m" (regs->regs[31]) 49 : : "memory"); 50 } 51 52 #endif /* _ASM_STACKTRACE_H */ 53