1 #include <linux/sched.h> 2 #include <linux/sched/debug.h> 3 #include <linux/stacktrace.h> 4 #include <linux/thread_info.h> 5 #include <linux/ftrace.h> 6 #include <linux/export.h> 7 #include <asm/ptrace.h> 8 #include <asm/stacktrace.h> 9 10 #include "kstack.h" 11 12 static void __save_stack_trace(struct thread_info *tp, 13 struct stack_trace *trace, 14 bool skip_sched) 15 { 16 unsigned long ksp, fp; 17 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 18 struct task_struct *t; 19 int graph = 0; 20 #endif 21 22 if (tp == current_thread_info()) { 23 stack_trace_flush(); 24 __asm__ __volatile__("mov %%fp, %0" : "=r" (ksp)); 25 } else { 26 ksp = tp->ksp; 27 } 28 29 fp = ksp + STACK_BIAS; 30 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 31 t = tp->task; 32 #endif 33 do { 34 struct sparc_stackf *sf; 35 struct pt_regs *regs; 36 unsigned long pc; 37 38 if (!kstack_valid(tp, fp)) 39 break; 40 41 sf = (struct sparc_stackf *) fp; 42 regs = (struct pt_regs *) (sf + 1); 43 44 if (kstack_is_trap_frame(tp, regs)) { 45 if (!(regs->tstate & TSTATE_PRIV)) 46 break; 47 pc = regs->tpc; 48 fp = regs->u_regs[UREG_I6] + STACK_BIAS; 49 } else { 50 pc = sf->callers_pc; 51 fp = (unsigned long)sf->fp + STACK_BIAS; 52 } 53 54 if (trace->skip > 0) 55 trace->skip--; 56 else if (!skip_sched || !in_sched_functions(pc)) { 57 trace->entries[trace->nr_entries++] = pc; 58 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 59 if ((pc + 8UL) == (unsigned long) &return_to_handler) { 60 struct ftrace_ret_stack *ret_stack; 61 ret_stack = ftrace_graph_get_ret_stack(t, 62 graph); 63 if (ret_stack) { 64 pc = ret_stack->ret; 65 if (trace->nr_entries < 66 trace->max_entries) 67 trace->entries[trace->nr_entries++] = pc; 68 graph++; 69 } 70 } 71 #endif 72 } 73 } while (trace->nr_entries < trace->max_entries); 74 } 75 76 void save_stack_trace(struct stack_trace *trace) 77 { 78 __save_stack_trace(current_thread_info(), trace, false); 79 } 80 EXPORT_SYMBOL_GPL(save_stack_trace); 81 82 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 83 { 84 struct thread_info *tp = task_thread_info(tsk); 85 86 __save_stack_trace(tp, trace, true); 87 } 88 EXPORT_SYMBOL_GPL(save_stack_trace_tsk); 89