LXR linux/mm/failslab.c

   1#include <linux/fault-inject.h>
   2#include <linux/slab.h>
   3
   4static struct {
   5        struct fault_attr attr;
   6        u32 ignore_gfp_wait;
   7        int cache_filter;
   8#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
   9        struct dentry *ignore_gfp_wait_file;
  10        struct dentry *cache_filter_file;
  11#endif
  12} failslab = {
  13        .attr = FAULT_ATTR_INITIALIZER,
  14        .ignore_gfp_wait = 1,
  15        .cache_filter = 0,
  16};
  17
  18bool should_failslab(size_t size, gfp_t gfpflags, unsigned long cache_flags)
  19{
  20        if (gfpflags & __GFP_NOFAIL)
  21                return false;
  22
  23        if (failslab.ignore_gfp_wait && (gfpflags & __GFP_WAIT))
  24                return false;
  25
  26        if (failslab.cache_filter && !(cache_flags & SLAB_FAILSLAB))
  27                return false;
  28
  29        return should_fail(&failslab.attr, size);
  30}
  31
  32static int __init setup_failslab(char *str)
  33{
  34        return setup_fault_attr(&failslab.attr, str);
  35}
  36__setup("failslab=", setup_failslab);
  37
  38#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
  39static int __init failslab_debugfs_init(void)
  40{
  41        mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
  42        struct dentry *dir;
  43        int err;
  44
  45        err = init_fault_attr_dentries(&failslab.attr, "failslab");
  46        if (err)
  47                return err;
  48        dir = failslab.attr.dentries.dir;
  49
  50        failslab.ignore_gfp_wait_file =
  51                debugfs_create_bool("ignore-gfp-wait", mode, dir,
  52                                      &failslab.ignore_gfp_wait);
  53
  54        failslab.cache_filter_file =
  55                debugfs_create_bool("cache-filter", mode, dir,
  56                                      &failslab.cache_filter);
  57
  58        if (!failslab.ignore_gfp_wait_file ||
  59            !failslab.cache_filter_file) {
  60                err = -ENOMEM;
  61                debugfs_remove(failslab.cache_filter_file);
  62                debugfs_remove(failslab.ignore_gfp_wait_file);
  63                cleanup_fault_attr_dentries(&failslab.attr);
  64        }
  65
  66        return err;
  67}
  68
  69late_initcall(failslab_debugfs_init);
  70
  71#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
  72