kernel/arch/x86/kernel/rh_stacktrace.c

65 lines
1.5 KiB
C

/*
* This file contains stacktrace functions that are in RHEL kABI whitelist.
*/
static int save_stack_address(struct stack_trace *trace, unsigned long addr,
bool nosched)
{
if (nosched && in_sched_functions(addr))
return 0;
if (trace->skip > 0) {
trace->skip--;
return 0;
}
if (trace->nr_entries >= trace->max_entries)
return -1;
trace->entries[trace->nr_entries++] = addr;
return 0;
}
static void noinline __save_stack_trace(struct stack_trace *trace,
struct task_struct *task, struct pt_regs *regs,
bool nosched)
{
struct unwind_state state;
unsigned long addr;
if (regs)
save_stack_address(trace, regs->ip, nosched);
for (unwind_start(&state, task, regs, NULL); !unwind_done(&state);
unwind_next_frame(&state)) {
addr = unwind_get_return_address(&state);
if (!addr || save_stack_address(trace, addr, nosched))
break;
}
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
/*
* Save stack-backtrace addresses into a stack_trace buffer.
*/
void save_stack_trace(struct stack_trace *trace)
{
trace->skip++;
__save_stack_trace(trace, current, NULL, false);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
if (!try_get_task_stack(tsk))
return;
if (tsk == current)
trace->skip++;
__save_stack_trace(trace, tsk, NULL, true);
put_task_stack(tsk);
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);