LXR linux/mm/failslab.c

   1#include <linux/fault-inject.h>
   2#include <linux/gfp.h>
   3
   4static struct {
   5        struct fault_attr attr;
   6        u32 ignore_gfp_wait;
   7#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
   8        struct dentry *ignore_gfp_wait_file;
   9#endif
  10} failslab = {
  11        .attr = FAULT_ATTR_INITIALIZER,
  12        .ignore_gfp_wait = 1,
  13};
  14
  15bool should_failslab(size_t size, gfp_t gfpflags)
  16{
  17        if (gfpflags & __GFP_NOFAIL)
  18                return false;
  19
  20        if (failslab.ignore_gfp_wait && (gfpflags & __GFP_WAIT))
  21                return false;
  22
  23        return should_fail(&failslab.attr, size);
  24}
  25
  26static int __init setup_failslab(char *str)
  27{
  28        return setup_fault_attr(&failslab.attr, str);
  29}
  30__setup("failslab=", setup_failslab);
  31
  32#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
  33
  34static int __init failslab_debugfs_init(void)
  35{
  36        mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
  37        struct dentry *dir;
  38        int err;
  39
  40        err = init_fault_attr_dentries(&failslab.attr, "failslab");
  41        if (err)
  42                return err;
  43        dir = failslab.attr.dentries.dir;
  44
  45        failslab.ignore_gfp_wait_file =
  46                debugfs_create_bool("ignore-gfp-wait", mode, dir,
  47                                      &failslab.ignore_gfp_wait);
  48
  49        if (!failslab.ignore_gfp_wait_file) {
  50                err = -ENOMEM;
  51                debugfs_remove(failslab.ignore_gfp_wait_file);
  52                cleanup_fault_attr_dentries(&failslab.attr);
  53        }
  54
  55        return err;
  56}
  57
  58late_initcall(failslab_debugfs_init);
  59
  60#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
  61