mm/failslab.c

   1 #include <linux/fault-inject.h>
   2 #include <linux/slab.h>
   3
   4 static struct {
   5         struct fault_attr attr;
   6         u32 ignore_gfp_wait;
   7         int cache_filter;
   8 } failslab = {
   9         .attr = FAULT_ATTR_INITIALIZER,
  10         .ignore_gfp_wait = 1,
  11         .cache_filter = 0,
  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_wait && (gfpflags & __GFP_WAIT))
  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         mode_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_wait))
  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 */