xref: /openbmc/linux/mm/failslab.c (revision 2572f00d)
1 #include <linux/fault-inject.h>
2 #include <linux/slab.h>
3 
4 static struct {
5 	struct fault_attr attr;
6 	bool ignore_gfp_reclaim;
7 	bool cache_filter;
8 } failslab = {
9 	.attr = FAULT_ATTR_INITIALIZER,
10 	.ignore_gfp_reclaim = true,
11 	.cache_filter = false,
12 };
13 
14 bool should_failslab(size_t size, gfp_t gfpflags, unsigned long cache_flags)
15 {
16 	if (gfpflags & __GFP_NOFAIL)
17 		return false;
18 
19 	if (failslab.ignore_gfp_reclaim && (gfpflags & __GFP_RECLAIM))
20 		return false;
21 
22 	if (failslab.cache_filter && !(cache_flags & SLAB_FAILSLAB))
23 		return false;
24 
25 	return should_fail(&failslab.attr, size);
26 }
27 
28 static int __init setup_failslab(char *str)
29 {
30 	return setup_fault_attr(&failslab.attr, str);
31 }
32 __setup("failslab=", setup_failslab);
33 
34 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
35 static int __init failslab_debugfs_init(void)
36 {
37 	struct dentry *dir;
38 	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
39 
40 	dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
41 	if (IS_ERR(dir))
42 		return PTR_ERR(dir);
43 
44 	if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
45 				&failslab.ignore_gfp_reclaim))
46 		goto fail;
47 	if (!debugfs_create_bool("cache-filter", mode, dir,
48 				&failslab.cache_filter))
49 		goto fail;
50 
51 	return 0;
52 fail:
53 	debugfs_remove_recursive(dir);
54 
55 	return -ENOMEM;
56 }
57 
58 late_initcall(failslab_debugfs_init);
59 
60 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
61