72 lines
2.0 KiB
C
72 lines
2.0 KiB
C
/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 and
|
|
* only version 2 as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
/*
|
|
* DLKM to register a callback with a ftrace event
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/init.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/tracepoint.h>
|
|
#include <linux/coresight.h>
|
|
|
|
#include <trace/events/exception.h>
|
|
|
|
static void abort_coresight_tracing(void *ignore, struct task_struct *task,\
|
|
unsigned long addr, unsigned int fsr)
|
|
{
|
|
coresight_abort();
|
|
pr_debug("control_trace: task_name: %s, addr: %lu, fsr:%u",\
|
|
(char *)task->comm, addr, fsr);
|
|
}
|
|
|
|
static void abort_tracing_undef_instr(void *ignore, struct pt_regs *regs,\
|
|
void *pc)
|
|
{
|
|
if (user_mode(regs)) {
|
|
coresight_abort();
|
|
pr_debug("control_trace: pc: %p", pc);
|
|
}
|
|
}
|
|
|
|
static int __init control_trace_init(void)
|
|
{
|
|
int ret_user_fault, ret_undef_instr;
|
|
ret_user_fault = register_trace_user_fault(abort_coresight_tracing,\
|
|
NULL);
|
|
ret_undef_instr = register_trace_undef_instr(abort_tracing_undef_instr,\
|
|
NULL);
|
|
if (ret_user_fault != 0 || ret_undef_instr != 0) {
|
|
pr_info("control_trace: Module Not Registered\n");
|
|
return (ret_user_fault < 0 ?\
|
|
ret_user_fault : ret_undef_instr);
|
|
}
|
|
pr_info("control_trace: Module Registered\n");
|
|
return 0;
|
|
}
|
|
|
|
module_init(control_trace_init);
|
|
|
|
static void __exit control_trace_exit(void)
|
|
{
|
|
unregister_trace_user_fault(abort_coresight_tracing, NULL);
|
|
unregister_trace_undef_instr(abort_tracing_undef_instr, NULL);
|
|
pr_info("control_trace: Module Removed\n");
|
|
}
|
|
|
|
module_exit(control_trace_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_DESCRIPTION("Kernel Module to abort tracing");
|