// SPDX-License-Identifier: GPL-2.0 // Copyright (C) 2005-2017 Andes Technology Corporation #include <linux/sched/debug.h> #include <linux/sched/task_stack.h> #include <linux/stacktrace.h> #include <linux/ftrace.h> void save_stack_trace(struct stack_trace *trace) { save_stack_trace_tsk(current, trace); } EXPORT_SYMBOL_GPL(save_stack_trace); void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) { unsigned long *fpn; int skip = trace->skip; int savesched; int graph_idx = 0; if (tsk == current) { __asm__ __volatile__("\tori\t%0, $fp, #0\n":"=r"(fpn)); savesched = 1; } else { fpn = (unsigned long *)thread_saved_fp(tsk); savesched = 0; } while (!kstack_end(fpn) && !((unsigned long)fpn & 0x3) && (fpn >= (unsigned long *)TASK_SIZE)) { unsigned long lpp, fpp; lpp = fpn[LP_OFFSET]; fpp = fpn[FP_OFFSET]; if (!__kernel_text_address(lpp)) break; else lpp = ftrace_graph_ret_addr(tsk, &graph_idx, lpp, NULL); if (savesched || !in_sched_functions(lpp)) { if (skip) { skip--; } else { trace->entries[trace->nr_entries++] = lpp; if (trace->nr_entries >= trace->max_entries) break; } } fpn = (unsigned long *)fpp; } } EXPORT_SYMBOL_GPL(save_stack_trace_tsk);