^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) * Stack trace utility for OpenRISC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (C) 2017 Stafford Horne <shorne@gmail.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * This file is licensed under the terms of the GNU General Public License
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * version 2. This program is licensed "as is" without any warranty of any
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * kind, whether express or implied.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * Losely based on work from sh and powerpc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/sched/debug.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/sched/task_stack.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/stacktrace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <asm/processor.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <asm/unwinder.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * Save stack-backtrace addresses into a stack_trace buffer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) save_stack_address(void *data, unsigned long addr, int reliable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) struct stack_trace *trace = data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) if (!reliable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) if (trace->skip > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) trace->skip--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) if (trace->nr_entries < trace->max_entries)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) trace->entries[trace->nr_entries++] = addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) void save_stack_trace(struct stack_trace *trace)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) unwind_stack(trace, (unsigned long *) &trace, save_stack_address);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) EXPORT_SYMBOL_GPL(save_stack_trace);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) save_stack_address_nosched(void *data, unsigned long addr, int reliable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) struct stack_trace *trace = (struct stack_trace *)data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) if (!reliable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) if (in_sched_functions(addr))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) if (trace->skip > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) trace->skip--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) if (trace->nr_entries < trace->max_entries)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) trace->entries[trace->nr_entries++] = addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) unsigned long *sp = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) if (!try_get_task_stack(tsk))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) if (tsk == current)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) sp = (unsigned long *) &sp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) unsigned long ksp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) /* Locate stack from kernel context */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) ksp = task_thread_info(tsk)->ksp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) ksp += STACK_FRAME_OVERHEAD; /* redzone */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) ksp += sizeof(struct pt_regs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) sp = (unsigned long *) ksp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) unwind_stack(trace, sp, save_stack_address_nosched);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) put_task_stack(tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) unwind_stack(trace, (unsigned long *) regs->sp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) save_stack_address_nosched);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) EXPORT_SYMBOL_GPL(save_stack_trace_regs);