1 #include <linux/sched.h> 2 #include <linux/stacktrace.h> 3 #include <linux/thread_info.h> 4 #include <linux/ftrace.h> 5 #include <linux/export.h> 6 #include <asm/ptrace.h> 7 #include <asm/stacktrace.h> 8 9 #include "kstack.h" 10 11 static void __save_stack_trace(struct thread_info *tp, 12 struct stack_trace *trace, 13 bool skip_sched) 14 { 15 unsigned long ksp, fp; 16 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 17 struct task_struct *t; 18 int graph = 0; 19 #endif 20 21 if (tp == current_thread_info()) { 22 stack_trace_flush(); 23 __asm__ __volatile__("mov %%fp, %0" : "=r" (ksp)); 24 } else { 25 ksp = tp->ksp; 26 } 27 28 fp = ksp + STACK_BIAS; 29 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 30 t = tp->task; 31 #endif 32 do { 33 struct sparc_stackf *sf; 34 struct pt_regs *regs; 35 unsigned long pc; 36 37 if (!kstack_valid(tp, fp)) 38 break; 39 40 sf = (struct sparc_stackf *) fp; 41 regs = (struct pt_regs *) (sf + 1); 42 43 if (kstack_is_trap_frame(tp, regs)) { 44 if (!(regs->tstate & TSTATE_PRIV)) 45 break; 46 pc = regs->tpc; 47 fp = regs->u_regs[UREG_I6] + STACK_BIAS; 48 } else { 49 pc = sf->callers_pc; 50 fp = (unsigned long)sf->fp + STACK_BIAS; 51 } 52 53 if (trace->skip > 0) 54 trace->skip--; 55 else if (!skip_sched || !in_sched_functions(pc)) { 56 trace->entries[trace->nr_entries++] = pc; 57 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 58 if ((pc + 8UL) == (unsigned long) &return_to_handler) { 59 int index = t->curr_ret_stack; 60 if (t->ret_stack && index >= graph) { 61 pc = t->ret_stack[index - graph].ret; 62 if (trace->nr_entries < 63 trace->max_entries) 64 trace->entries[trace->nr_entries++] = pc; 65 graph++; 66 } 67 } 68 #endif 69 } 70 } while (trace->nr_entries < trace->max_entries); 71 } 72 73 void save_stack_trace(struct stack_trace *trace) 74 { 75 __save_stack_trace(current_thread_info(), trace, false); 76 } 77 EXPORT_SYMBOL_GPL(save_stack_trace); 78 79 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 80 { 81 struct thread_info *tp = task_thread_info(tsk); 82 83 __save_stack_trace(tp, trace, true); 84 } 85 EXPORT_SYMBOL_GPL(save_stack_trace_tsk); 86