linux-zen-desktop/arch/openrisc/kernel/stacktrace.c

101 lines
2.1 KiB
C

/*
* Stack trace utility for OpenRISC
*
* Copyright (C) 2017 Stafford Horne <shorne@gmail.com>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*
* Losely based on work from sh and powerpc.
*/
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
#include <linux/stacktrace.h>
#include <asm/processor.h>
#include <asm/unwinder.h>
/*
* Save stack-backtrace addresses into a stack_trace buffer.
*/
static void
save_stack_address(void *data, unsigned long addr, int reliable)
{
struct stack_trace *trace = data;
if (!reliable)
return;
if (trace->skip > 0) {
trace->skip--;
return;
}
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = addr;
}
void save_stack_trace(struct stack_trace *trace)
{
unwind_stack(trace, (unsigned long *) &trace, save_stack_address);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
static void
save_stack_address_nosched(void *data, unsigned long addr, int reliable)
{
struct stack_trace *trace = (struct stack_trace *)data;
if (!reliable)
return;
if (in_sched_functions(addr))
return;
if (trace->skip > 0) {
trace->skip--;
return;
}
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = addr;
}
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
unsigned long *sp = NULL;
if (!try_get_task_stack(tsk))
return;
if (tsk == current)
sp = (unsigned long *) &sp;
else {
unsigned long ksp;
/* Locate stack from kernel context */
ksp = task_thread_info(tsk)->ksp;
ksp += STACK_FRAME_OVERHEAD; /* redzone */
ksp += sizeof(struct pt_regs);
sp = (unsigned long *) ksp;
}
unwind_stack(trace, sp, save_stack_address_nosched);
put_task_stack(tsk);
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
void
save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
{
unwind_stack(trace, (unsigned long *) regs->sp,
save_stack_address_nosched);
}
EXPORT_SYMBOL_GPL(save_stack_trace_regs);