linux-stable/lib/memory-notifier-error-inject.c
Akinobu Mita 9579f5bd31 memory: memory notifier error injection module
This provides the ability to inject artifical errors to memory hotplug
notifier chain callbacks.  It is controlled through debugfs interface
under /sys/kernel/debug/notifier-error-inject/memory

If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".

Example: Inject memory hotplug offline error (-12 == -ENOMEM)

	# cd /sys/kernel/debug/notifier-error-inject/memory
	# echo -12 > actions/MEM_GOING_OFFLINE/error
	# echo offline > /sys/devices/system/memory/memoryXXX/state
	bash: echo: write error: Cannot allocate memory

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:22 -07:00

48 lines
1.1 KiB
C

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/memory.h>
#include "notifier-error-inject.h"
static int priority;
module_param(priority, int, 0);
MODULE_PARM_DESC(priority, "specify memory notifier priority");
static struct notifier_err_inject memory_notifier_err_inject = {
.actions = {
{ NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_ONLINE) },
{ NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_OFFLINE) },
{}
}
};
static struct dentry *dir;
static int err_inject_init(void)
{
int err;
dir = notifier_err_inject_init("memory", notifier_err_inject_dir,
&memory_notifier_err_inject, priority);
if (IS_ERR(dir))
return PTR_ERR(dir);
err = register_memory_notifier(&memory_notifier_err_inject.nb);
if (err)
debugfs_remove_recursive(dir);
return err;
}
static void err_inject_exit(void)
{
unregister_memory_notifier(&memory_notifier_err_inject.nb);
debugfs_remove_recursive(dir);
}
module_init(err_inject_init);
module_exit(err_inject_exit);
MODULE_DESCRIPTION("memory notifier error injection module");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");