linux/lib/cpu-notifier-error-inject.c
Sebastian Andrzej Siewior 8c58898b3e fault-injection/cpu: Convert to hotplug state machine
Install the callbacks via the state machine.

This is just a temporary vehicle to keep the interface working for now,
It'll be replaced by the sysfs interface which allows to step through the
hotplug state machine step by step.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160906170457.32393-15-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-19 21:44:31 +02:00

85 lines
1.9 KiB
C

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/cpu.h>
#include "notifier-error-inject.h"
static int priority;
module_param(priority, int, 0);
MODULE_PARM_DESC(priority, "specify cpu notifier priority");
#define UP_PREPARE 0
#define UP_PREPARE_FROZEN 0
#define DOWN_PREPARE 0
#define DOWN_PREPARE_FROZEN 0
static struct notifier_err_inject cpu_notifier_err_inject = {
.actions = {
{ NOTIFIER_ERR_INJECT_ACTION(UP_PREPARE) },
{ NOTIFIER_ERR_INJECT_ACTION(UP_PREPARE_FROZEN) },
{ NOTIFIER_ERR_INJECT_ACTION(DOWN_PREPARE) },
{ NOTIFIER_ERR_INJECT_ACTION(DOWN_PREPARE_FROZEN) },
{}
}
};
static int notf_err_handle(struct notifier_err_inject_action *action)
{
int ret;
ret = action->error;
if (ret)
pr_info("Injecting error (%d) to %s\n", ret, action->name);
return ret;
}
static int notf_err_inj_up_prepare(unsigned int cpu)
{
if (!cpuhp_tasks_frozen)
return notf_err_handle(&cpu_notifier_err_inject.actions[0]);
else
return notf_err_handle(&cpu_notifier_err_inject.actions[1]);
}
static int notf_err_inj_dead(unsigned int cpu)
{
if (!cpuhp_tasks_frozen)
return notf_err_handle(&cpu_notifier_err_inject.actions[2]);
else
return notf_err_handle(&cpu_notifier_err_inject.actions[3]);
}
static struct dentry *dir;
static int err_inject_init(void)
{
int err;
dir = notifier_err_inject_init("cpu", notifier_err_inject_dir,
&cpu_notifier_err_inject, priority);
if (IS_ERR(dir))
return PTR_ERR(dir);
err = cpuhp_setup_state_nocalls(CPUHP_NOTF_ERR_INJ_PREPARE,
"cpu-err-notif:prepare",
notf_err_inj_up_prepare,
notf_err_inj_dead);
if (err)
debugfs_remove_recursive(dir);
return err;
}
static void err_inject_exit(void)
{
cpuhp_remove_state_nocalls(CPUHP_NOTF_ERR_INJ_PREPARE);
debugfs_remove_recursive(dir);
}
module_init(err_inject_init);
module_exit(err_inject_exit);
MODULE_DESCRIPTION("CPU notifier error injection module");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");