Revert "BACKPORT: [UPSTREAM] mm: new shrinker API"

This reverts commit db537c9914552c3472bd5c75ffe72327e9076f76.

1 files changed, 9 insertions, 29 deletions

diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h
index 884e76222..ac6b8ee07 100644
--- a/include/linux/shrinker.h
+++ b/include/linux/shrinker.h
@@ -4,12 +4,6 @@
 /*
  * This struct is used to pass information from page reclaim to the shrinkers.
  * We consolidate the values for easier extention later.
- *
- * The 'gfpmask' refers to the allocation we are currently trying to
- * fulfil.
- *
- * Note that 'shrink' will be passed nr_to_scan == 0 when the VM is
- * querying the cache size, so a fastpath for that case is appropriate.
  */
 struct shrink_control {
 	gfp_t gfp_mask;
@@ -18,37 +12,23 @@ struct shrink_control {
 	unsigned long nr_to_scan;
 };
 
-#define SHRINK_STOP (~0UL)
 /*
  * A callback you can register to apply pressure to ageable caches.
  *
- * @shrink() should look through the least-recently-used 'nr_to_scan' entries
- * and attempt to free them up.  It should return the number of objects which
- * remain in the cache.  If it returns -1, it means it cannot do any scanning at
- * this time (eg. there is a risk of deadlock).
+ * 'sc' is passed shrink_control which includes a count 'nr_to_scan'
+ * and a 'gfpmask'.  It should look through the least-recently-used
+ * 'nr_to_scan' entries and attempt to free them up.  It should return
+ * the number of objects which remain in the cache.  If it returns -1, it means
+ * it cannot do any scanning at this time (eg. there is a risk of deadlock).
  *
- * @count_objects should return the number of freeable items in the cache. If
- * there are no objects to free or the number of freeable items cannot be
- * determined, it should return 0. No deadlock checks should be done during the
- * count callback - the shrinker relies on aggregating scan counts that couldn't
- * be executed due to potential deadlocks to be run at a later call when the
- * deadlock condition is no longer pending.
+ * The 'gfpmask' refers to the allocation we are currently trying to
+ * fulfil.
  *
- * @scan_objects will only be called if @count_objects returned a non-zero
- * value for the number of freeable objects. The callout should scan the cache
- * and attempt to free items from the cache. It should then return the number
- * of objects freed during the scan, or SHRINK_STOP if progress cannot be made
- * due to potential deadlocks. If SHRINK_STOP is returned, then no further
- * attempts to call the @scan_objects will be made from the current reclaim
- * context.
+ * Note that 'shrink' will be passed nr_to_scan == 0 when the VM is
+ * querying the cache size, so a fastpath for that case is appropriate.
  */
 struct shrinker {
 	int (*shrink)(struct shrinker *, struct shrink_control *sc);
-	unsigned long (*count_objects)(struct shrinker *,
-				       struct shrink_control *sc);
-	unsigned long (*scan_objects)(struct shrinker *,
-				      struct shrink_control *sc);
-
 	int seeks;	/* seeks to recreate an obj */
 	long batch;	/* reclaim batch size, 0 = default */