Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs pile 4 from Al Viro:
 "list_lru pile, mostly"

This came out of Andrew's pile, Al ended up doing the merge work so that
Andrew didn't have to.

Additionally, a few fixes.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (42 commits)
  super: fix for destroy lrus
  list_lru: dynamically adjust node arrays
  shrinker: Kill old ->shrink API.
  shrinker: convert remaining shrinkers to count/scan API
  staging/lustre/libcfs: cleanup linux-mem.h
  staging/lustre/ptlrpc: convert to new shrinker API
  staging/lustre/obdclass: convert lu_object shrinker to count/scan API
  staging/lustre/ldlm: convert to shrinkers to count/scan API
  hugepage: convert huge zero page shrinker to new shrinker API
  i915: bail out earlier when shrinker cannot acquire mutex
  drivers: convert shrinkers to new count/scan API
  fs: convert fs shrinkers to new scan/count API
  xfs: fix dquot isolation hang
  xfs-convert-dquot-cache-lru-to-list_lru-fix
  xfs: convert dquot cache lru to list_lru
  xfs: rework buffer dispose list tracking
  xfs-convert-buftarg-lru-to-generic-code-fix
  xfs: convert buftarg LRU to generic code
  fs: convert inode and dentry shrinking to be node aware
  vmscan: per-node deferred work
  ...

Documentation/filesystems/porting

@@ -451,3 +451,7 @@ in your dentry operations instead.
 --
 [mandatory]
 	->readdir() is gone now; switch to ->iterate()
+[mandatory]
+	vfs_follow_link has been removed.  Filesystems must use nd_set_link
+	from ->follow_link for normal symlinks, or nd_jump_link for magic
+	/proc/<pid> style links.

arch/x86/kvm/mmu.c

@@ -4421,13 +4421,12 @@ void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm)
 	}
 }
 
-static int mmu_shrink(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long
+mmu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
 	struct kvm *kvm;
 	int nr_to_scan = sc->nr_to_scan;
-
-	if (nr_to_scan == 0)
-		goto out;
+	unsigned long freed = 0;
 
 	raw_spin_lock(&kvm_lock);
 
@@ -4462,25 +4461,37 @@ static int mmu_shrink(struct shrinker *shrink, struct shrink_control *sc)
 			goto unlock;
 		}
 
-		prepare_zap_oldest_mmu_page(kvm, &invalid_list);
+		if (prepare_zap_oldest_mmu_page(kvm, &invalid_list))
+			freed++;
 		kvm_mmu_commit_zap_page(kvm, &invalid_list);
 
 unlock:
 		spin_unlock(&kvm->mmu_lock);
 		srcu_read_unlock(&kvm->srcu, idx);
 
+		/*
+		 * unfair on small ones
+		 * per-vm shrinkers cry out
+		 * sadness comes quickly
+		 */
 		list_move_tail(&kvm->vm_list, &vm_list);
 		break;
 	}
 
 	raw_spin_unlock(&kvm_lock);
+	return freed;
 
-out:
+}
+
+static unsigned long
+mmu_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
 	return percpu_counter_read_positive(&kvm_total_used_mmu_pages);
 }
 
 static struct shrinker mmu_shrinker = {
-	.shrink = mmu_shrink,
+	.count_objects = mmu_shrink_count,
+	.scan_objects = mmu_shrink_scan,
 	.seeks = DEFAULT_SEEKS * 10,
 };
 

drivers/gpu/drm/i915/i915_dma.c

@@ -1676,7 +1676,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	return 0;
 
 out_gem_unload:
-	if (dev_priv->mm.inactive_shrinker.shrink)
+	if (dev_priv->mm.inactive_shrinker.scan_objects)
 		unregister_shrinker(&dev_priv->mm.inactive_shrinker);
 
 	if (dev->pdev->msi_enabled)
@@ -1715,7 +1715,7 @@ int i915_driver_unload(struct drm_device *dev)
 
 	i915_teardown_sysfs(dev);
 
-	if (dev_priv->mm.inactive_shrinker.shrink)
+	if (dev_priv->mm.inactive_shrinker.scan_objects)
 		unregister_shrinker(&dev_priv->mm.inactive_shrinker);
 
 	mutex_lock(&dev->struct_mutex);

drivers/gpu/drm/i915/i915_gem.c

@@ -57,10 +57,12 @@ static void i915_gem_object_update_fence(struct drm_i915_gem_object *obj,
 					 struct drm_i915_fence_reg *fence,
 					 bool enable);
 
-static int i915_gem_inactive_shrink(struct shrinker *shrinker,
-				    struct shrink_control *sc);
+static unsigned long i915_gem_inactive_count(struct shrinker *shrinker,
+					     struct shrink_control *sc);
+static unsigned long i915_gem_inactive_scan(struct shrinker *shrinker,
+					    struct shrink_control *sc);
 static long i915_gem_purge(struct drm_i915_private *dev_priv, long target);
-static void i915_gem_shrink_all(struct drm_i915_private *dev_priv);
+static long i915_gem_shrink_all(struct drm_i915_private *dev_priv);
 static void i915_gem_object_truncate(struct drm_i915_gem_object *obj);
 
 static bool cpu_cache_is_coherent(struct drm_device *dev,
@@ -1769,16 +1771,21 @@ i915_gem_purge(struct drm_i915_private *dev_priv, long target)
 	return __i915_gem_shrink(dev_priv, target, true);
 }
 
-static void
+static long
 i915_gem_shrink_all(struct drm_i915_private *dev_priv)
 {
 	struct drm_i915_gem_object *obj, *next;
+	long freed = 0;
 
 	i915_gem_evict_everything(dev_priv->dev);
 
 	list_for_each_entry_safe(obj, next, &dev_priv->mm.unbound_list,
-				 global_list)
+				 global_list) {
+		if (obj->pages_pin_count == 0)
+			freed += obj->base.size >> PAGE_SHIFT;
 		i915_gem_object_put_pages(obj);
+	}
+	return freed;
 }
 
 static int
@@ -4558,7 +4565,8 @@ i915_gem_load(struct drm_device *dev)
 
 	dev_priv->mm.interruptible = true;
 
-	dev_priv->mm.inactive_shrinker.shrink = i915_gem_inactive_shrink;
+	dev_priv->mm.inactive_shrinker.scan_objects = i915_gem_inactive_scan;
+	dev_priv->mm.inactive_shrinker.count_objects = i915_gem_inactive_count;
 	dev_priv->mm.inactive_shrinker.seeks = DEFAULT_SEEKS;
 	register_shrinker(&dev_priv->mm.inactive_shrinker);
 }
@@ -4781,8 +4789,8 @@ static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
 #endif
 }
 
-static int
-i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc)
+static unsigned long
+i915_gem_inactive_count(struct shrinker *shrinker, struct shrink_control *sc)
 {
 	struct drm_i915_private *dev_priv =
 		container_of(shrinker,
@@ -4790,45 +4798,35 @@ i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc)
 			     mm.inactive_shrinker);
 	struct drm_device *dev = dev_priv->dev;
 	struct drm_i915_gem_object *obj;
-	int nr_to_scan = sc->nr_to_scan;
 	bool unlock = true;
-	int cnt;
+	unsigned long count;
 
 	if (!mutex_trylock(&dev->struct_mutex)) {
 		if (!mutex_is_locked_by(&dev->struct_mutex, current))
-			return 0;
+			return SHRINK_STOP;
 
 		if (dev_priv->mm.shrinker_no_lock_stealing)
-			return 0;
+			return SHRINK_STOP;
 
 		unlock = false;
 	}
 
-	if (nr_to_scan) {
-		nr_to_scan -= i915_gem_purge(dev_priv, nr_to_scan);
-		if (nr_to_scan > 0)
-			nr_to_scan -= __i915_gem_shrink(dev_priv, nr_to_scan,
-							false);
-		if (nr_to_scan > 0)
-			i915_gem_shrink_all(dev_priv);
-	}
-
-	cnt = 0;
+	count = 0;
 	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list)
 		if (obj->pages_pin_count == 0)
-			cnt += obj->base.size >> PAGE_SHIFT;
+			count += obj->base.size >> PAGE_SHIFT;
 
 	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
 		if (obj->active)
 			continue;
 
 		if (obj->pin_count == 0 && obj->pages_pin_count == 0)
-			cnt += obj->base.size >> PAGE_SHIFT;
+			count += obj->base.size >> PAGE_SHIFT;
 	}
 
 	if (unlock)
 		mutex_unlock(&dev->struct_mutex);
-	return cnt;
+	return count;
 }
 
 /* All the new VM stuff */
@@ -4892,6 +4890,40 @@ unsigned long i915_gem_obj_size(struct drm_i915_gem_object *o,
 	return 0;
 }
 
+static unsigned long
+i915_gem_inactive_scan(struct shrinker *shrinker, struct shrink_control *sc)
+{
+	struct drm_i915_private *dev_priv =
+		container_of(shrinker,
+			     struct drm_i915_private,
+			     mm.inactive_shrinker);
+	struct drm_device *dev = dev_priv->dev;
+	int nr_to_scan = sc->nr_to_scan;
+	unsigned long freed;
+	bool unlock = true;
+
+	if (!mutex_trylock(&dev->struct_mutex)) {
+		if (!mutex_is_locked_by(&dev->struct_mutex, current))
+			return 0;
+
+		if (dev_priv->mm.shrinker_no_lock_stealing)
+			return 0;
+
+		unlock = false;
+	}
+
+	freed = i915_gem_purge(dev_priv, nr_to_scan);
+	if (freed < nr_to_scan)
+		freed += __i915_gem_shrink(dev_priv, nr_to_scan,
+							false);
+	if (freed < nr_to_scan)
+		freed += i915_gem_shrink_all(dev_priv);
+
+	if (unlock)
+		mutex_unlock(&dev->struct_mutex);
+	return freed;
+}
+
 struct i915_vma *i915_gem_obj_to_vma(struct drm_i915_gem_object *obj,
 				     struct i915_address_space *vm)
 {

drivers/gpu/drm/ttm/ttm_page_alloc.c

@@ -377,28 +377,26 @@ out:
 	return nr_free;
 }
 
-/* Get good estimation how many pages are free in pools */
-static int ttm_pool_get_num_unused_pages(void)
-{
-	unsigned i;
-	int total = 0;
-	for (i = 0; i < NUM_POOLS; ++i)
-		total += _manager->pools[i].npages;
-
-	return total;
-}
-
 /**
  * Callback for mm to request pool to reduce number of page held.
+ *
+ * XXX: (dchinner) Deadlock warning!
+ *
+ * ttm_page_pool_free() does memory allocation using GFP_KERNEL.  that means
+ * this can deadlock when called a sc->gfp_mask that is not equal to
+ * GFP_KERNEL.
+ *
+ * This code is crying out for a shrinker per pool....
  */
-static int ttm_pool_mm_shrink(struct shrinker *shrink,
-			      struct shrink_control *sc)
+static unsigned long
+ttm_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
 	static atomic_t start_pool = ATOMIC_INIT(0);
 	unsigned i;
 	unsigned pool_offset = atomic_add_return(1, &start_pool);
 	struct ttm_page_pool *pool;
 	int shrink_pages = sc->nr_to_scan;
+	unsigned long freed = 0;
 
 	pool_offset = pool_offset % NUM_POOLS;
 	/* select start pool in round robin fashion */
@@ -408,14 +406,28 @@ static int ttm_pool_mm_shrink(struct shrinker *shrink,
 			break;
 		pool = &_manager->pools[(i + pool_offset)%NUM_POOLS];
 		shrink_pages = ttm_page_pool_free(pool, nr_free);
+		freed += nr_free - shrink_pages;
 	}
-	/* return estimated number of unused pages in pool */
-	return ttm_pool_get_num_unused_pages();
+	return freed;
+}
+
+
+static unsigned long
+ttm_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+	unsigned i;
+	unsigned long count = 0;
+
+	for (i = 0; i < NUM_POOLS; ++i)
+		count += _manager->pools[i].npages;
+
+	return count;
 }
 
 static void ttm_pool_mm_shrink_init(struct ttm_pool_manager *manager)
 {
-	manager->mm_shrink.shrink = &ttm_pool_mm_shrink;
+	manager->mm_shrink.count_objects = ttm_pool_shrink_count;
+	manager->mm_shrink.scan_objects = ttm_pool_shrink_scan;
 	manager->mm_shrink.seeks = 1;
 	register_shrinker(&manager->mm_shrink);
 }

drivers/gpu/drm/ttm/ttm_page_alloc_dma.c

@@ -918,19 +918,6 @@ int ttm_dma_populate(struct ttm_dma_tt *ttm_dma, struct device *dev)
 }
 EXPORT_SYMBOL_GPL(ttm_dma_populate);
 
-/* Get good estimation how many pages are free in pools */
-static int ttm_dma_pool_get_num_unused_pages(void)
-{
-	struct device_pools *p;
-	unsigned total = 0;
-
-	mutex_lock(&_manager->lock);
-	list_for_each_entry(p, &_manager->pools, pools)
-		total += p->pool->npages_free;
-	mutex_unlock(&_manager->lock);
-	return total;
-}
-
 /* Put all pages in pages list to correct pool to wait for reuse */
 void ttm_dma_unpopulate(struct ttm_dma_tt *ttm_dma, struct device *dev)
 {
@@ -1002,18 +989,29 @@ EXPORT_SYMBOL_GPL(ttm_dma_unpopulate);
 
 /**
  * Callback for mm to request pool to reduce number of page held.
+ *
+ * XXX: (dchinner) Deadlock warning!
+ *
+ * ttm_dma_page_pool_free() does GFP_KERNEL memory allocation, and so attention
+ * needs to be paid to sc->gfp_mask to determine if this can be done or not.
+ * GFP_KERNEL memory allocation in a GFP_ATOMIC reclaim context woul dbe really
+ * bad.
+ *
+ * I'm getting sadder as I hear more pathetical whimpers about needing per-pool
+ * shrinkers
  */
-static int ttm_dma_pool_mm_shrink(struct shrinker *shrink,
-				  struct shrink_control *sc)
+static unsigned long
+ttm_dma_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
 	static atomic_t start_pool = ATOMIC_INIT(0);
 	unsigned idx = 0;
 	unsigned pool_offset = atomic_add_return(1, &start_pool);
 	unsigned shrink_pages = sc->nr_to_scan;
 	struct device_pools *p;
+	unsigned long freed = 0;
 
 	if (list_empty(&_manager->pools))
-		return 0;
+		return SHRINK_STOP;
 
 	mutex_lock(&_manager->lock);
 	pool_offset = pool_offset % _manager->npools;
@@ -1029,18 +1027,33 @@ static int ttm_dma_pool_mm_shrink(struct shrinker *shrink,
 			continue;
 		nr_free = shrink_pages;
 		shrink_pages = ttm_dma_page_pool_free(p->pool, nr_free);
+		freed += nr_free - shrink_pages;
+
 		pr_debug("%s: (%s:%d) Asked to shrink %d, have %d more to go\n",
 			 p->pool->dev_name, p->pool->name, current->pid,
 			 nr_free, shrink_pages);
 	}
 	mutex_unlock(&_manager->lock);
-	/* return estimated number of unused pages in pool */
-	return ttm_dma_pool_get_num_unused_pages();
+	return freed;
+}
+
+static unsigned long
+ttm_dma_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+	struct device_pools *p;
+	unsigned long count = 0;
+
+	mutex_lock(&_manager->lock);
+	list_for_each_entry(p, &_manager->pools, pools)
+		count += p->pool->npages_free;
+	mutex_unlock(&_manager->lock);
+	return count;
 }
 
 static void ttm_dma_pool_mm_shrink_init(struct ttm_pool_manager *manager)
 {
-	manager->mm_shrink.shrink = &ttm_dma_pool_mm_shrink;
+	manager->mm_shrink.count_objects = ttm_dma_pool_shrink_count;
+	manager->mm_shrink.scan_objects = &ttm_dma_pool_shrink_scan;
 	manager->mm_shrink.seeks = 1;
 	register_shrinker(&manager->mm_shrink);
 }

drivers/md/bcache/btree.c

@@ -597,24 +597,19 @@ static int mca_reap(struct btree *b, struct closure *cl, unsigned min_order)
 	return 0;
 }
 
-static int bch_mca_shrink(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long bch_mca_scan(struct shrinker *shrink,
+				  struct shrink_control *sc)
 {
 	struct cache_set *c = container_of(shrink, struct cache_set, shrink);
 	struct btree *b, *t;
 	unsigned long i, nr = sc->nr_to_scan;
+	unsigned long freed = 0;
 
 	if (c->shrinker_disabled)
-		return 0;
+		return SHRINK_STOP;
 
 	if (c->try_harder)
-		return 0;
-
-	/*
-	 * If nr == 0, we're supposed to return the number of items we have
-	 * cached. Not allowed to return -1.
-	 */
-	if (!nr)
-		return mca_can_free(c) * c->btree_pages;
+		return SHRINK_STOP;
 
 	/* Return -1 if we can't do anything right now */
 	if (sc->gfp_mask & __GFP_WAIT)
@@ -634,14 +629,14 @@ static int bch_mca_shrink(struct shrinker *shrink, struct shrink_control *sc)
 
 	i = 0;
 	list_for_each_entry_safe(b, t, &c->btree_cache_freeable, list) {
-		if (!nr)
+		if (freed >= nr)
 			break;
 
 		if (++i > 3 &&
 		    !mca_reap(b, NULL, 0)) {
 			mca_data_free(b);
 			rw_unlock(true, b);
-			--nr;
+			freed++;
 		}
 	}
 
@@ -652,7 +647,7 @@ static int bch_mca_shrink(struct shrinker *shrink, struct shrink_control *sc)
 	if (list_empty(&c->btree_cache))
 		goto out;
 
-	for (i = 0; nr && i < c->bucket_cache_used; i++) {
+	for (i = 0; (nr--) && i < c->bucket_cache_used; i++) {
 		b = list_first_entry(&c->btree_cache, struct btree, list);
 		list_rotate_left(&c->btree_cache);
 
@@ -661,14 +656,27 @@ static int bch_mca_shrink(struct shrinker *shrink, struct shrink_control *sc)
 			mca_bucket_free(b);
 			mca_data_free(b);
 			rw_unlock(true, b);
-			--nr;
+			freed++;
 		} else
 			b->accessed = 0;
 	}
 out:
-	nr = mca_can_free(c) * c->btree_pages;
 	mutex_unlock(&c->bucket_lock);
-	return nr;
+	return freed;
+}
+
+static unsigned long bch_mca_count(struct shrinker *shrink,
+				   struct shrink_control *sc)
+{
+	struct cache_set *c = container_of(shrink, struct cache_set, shrink);
+
+	if (c->shrinker_disabled)
+		return 0;
+
+	if (c->try_harder)
+		return 0;
+
+	return mca_can_free(c) * c->btree_pages;
 }
 
 void bch_btree_cache_free(struct cache_set *c)
@@ -737,7 +745,8 @@ int bch_btree_cache_alloc(struct cache_set *c)
 		c->verify_data = NULL;
 #endif
 
-	c->shrink.shrink = bch_mca_shrink;
+	c->shrink.count_objects = bch_mca_count;
+	c->shrink.scan_objects = bch_mca_scan;
 	c->shrink.seeks = 4;
 	c->shrink.batch = c->btree_pages * 2;
 	register_shrinker(&c->shrink);

drivers/md/bcache/sysfs.c

@@ -556,7 +556,7 @@ STORE(__bch_cache_set)
 		struct shrink_control sc;
 		sc.gfp_mask = GFP_KERNEL;
 		sc.nr_to_scan = strtoul_or_return(buf);
-		c->shrink.shrink(&c->shrink, &sc);
+		c->shrink.scan_objects(&c->shrink, &sc);
 	}
 
 	sysfs_strtoul(congested_read_threshold_us,

drivers/md/dm-bufio.c

@@ -1425,62 +1425,75 @@ static int __cleanup_old_buffer(struct dm_buffer *b, gfp_t gfp,
 				unsigned long max_jiffies)
 {
 	if (jiffies - b->last_accessed < max_jiffies)
-		return 1;
+		return 0;
 
 	if (!(gfp & __GFP_IO)) {
 		if (test_bit(B_READING, &b->state) ||
 		    test_bit(B_WRITING, &b->state) ||
 		    test_bit(B_DIRTY, &b->state))
-			return 1;
+			return 0;
 	}
 
 	if (b->hold_count)
-		return 1;
+		return 0;
 
 	__make_buffer_clean(b);
 	__unlink_buffer(b);
 	__free_buffer_wake(b);
 
-	return 0;
+	return 1;
 }
 
-static void __scan(struct dm_bufio_client *c, unsigned long nr_to_scan,
-		   struct shrink_control *sc)
+static long __scan(struct dm_bufio_client *c, unsigned long nr_to_scan,
+		   gfp_t gfp_mask)
 {
 	int l;
 	struct dm_buffer *b, *tmp;
+	long freed = 0;
 
 	for (l = 0; l < LIST_SIZE; l++) {
-		list_for_each_entry_safe_reverse(b, tmp, &c->lru[l], lru_list)
-			if (!__cleanup_old_buffer(b, sc->gfp_mask, 0) &&
-			    !--nr_to_scan)
-				return;
+		list_for_each_entry_safe_reverse(b, tmp, &c->lru[l], lru_list) {
+			freed += __cleanup_old_buffer(b, gfp_mask, 0);
+			if (!--nr_to_scan)
+				break;
+		}
 		dm_bufio_cond_resched();
 	}
+	return freed;
 }
 
-static int shrink(struct shrinker *shrinker, struct shrink_control *sc)
+static unsigned long
+dm_bufio_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
-	struct dm_bufio_client *c =
-	    container_of(shrinker, struct dm_bufio_client, shrinker);
-	unsigned long r;
-	unsigned long nr_to_scan = sc->nr_to_scan;
+	struct dm_bufio_client *c;
+	unsigned long freed;
 
+	c = container_of(shrink, struct dm_bufio_client, shrinker);
 	if (sc->gfp_mask & __GFP_IO)
 		dm_bufio_lock(c);
 	else if (!dm_bufio_trylock(c))
-		return !nr_to_scan ? 0 : -1;
+		return SHRINK_STOP;
 
-	if (nr_to_scan)
-		__scan(c, nr_to_scan, sc);
+	freed  = __scan(c, sc->nr_to_scan, sc->gfp_mask);
+	dm_bufio_unlock(c);
+	return freed;
+}
 
-	r = c->n_buffers[LIST_CLEAN] + c->n_buffers[LIST_DIRTY];
-	if (r > INT_MAX)
-		r = INT_MAX;
+static unsigned long
+dm_bufio_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+	struct dm_bufio_client *c;
+	unsigned long count;
 
-	dm_bufio_unlock(c);
+	c = container_of(shrink, struct dm_bufio_client, shrinker);
+	if (sc->gfp_mask & __GFP_IO)
+		dm_bufio_lock(c);
+	else if (!dm_bufio_trylock(c))
+		return 0;
 
-	return r;
+	count = c->n_buffers[LIST_CLEAN] + c->n_buffers[LIST_DIRTY];
+	dm_bufio_unlock(c);
+	return count;
 }
 
 /*
@@ -1582,7 +1595,8 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign
 	__cache_size_refresh();
 	mutex_unlock(&dm_bufio_clients_lock);
 
-	c->shrinker.shrink = shrink;
+	c->shrinker.count_objects = dm_bufio_shrink_count;
+	c->shrinker.scan_objects = dm_bufio_shrink_scan;
 	c->shrinker.seeks = 1;
 	c->shrinker.batch = 0;
 	register_shrinker(&c->shrinker);
@@ -1669,7 +1683,7 @@ static void cleanup_old_buffers(void)
 			struct dm_buffer *b;
 			b = list_entry(c->lru[LIST_CLEAN].prev,
 				       struct dm_buffer, lru_list);
-			if (__cleanup_old_buffer(b, 0, max_age * HZ))
+			if (!__cleanup_old_buffer(b, 0, max_age * HZ))
 				break;
 			dm_bufio_cond_resched();
 		}

drivers/staging/android/ashmem.c

@@ -341,27 +341,26 @@ out:
 /*
  * ashmem_shrink - our cache shrinker, called from mm/vmscan.c :: shrink_slab
  *
- * 'nr_to_scan' is the number of objects (pages) to prune, or 0 to query how
- * many objects (pages) we have in total.
+ * 'nr_to_scan' is the number of objects to scan for freeing.
  *
  * 'gfp_mask' is the mask of the allocation that got us into this mess.
  *
- * Return value is the number of objects (pages) remaining, or -1 if we cannot
+ * Return value is the number of objects freed or -1 if we cannot
  * proceed without risk of deadlock (due to gfp_mask).
  *
  * We approximate LRU via least-recently-unpinned, jettisoning unpinned partial
  * chunks of ashmem regions LRU-wise one-at-a-time until we hit 'nr_to_scan'
  * pages freed.
  */
-static int ashmem_shrink(struct shrinker *s, struct shrink_control *sc)
+static unsigned long
+ashmem_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
 	struct ashmem_range *range, *next;
+	unsigned long freed = 0;
 
 	/* We might recurse into filesystem code, so bail out if necessary */
-	if (sc->nr_to_scan && !(sc->gfp_mask & __GFP_FS))
-		return -1;
-	if (!sc->nr_to_scan)
-		return lru_count;
+	if (!(sc->gfp_mask & __GFP_FS))
+		return SHRINK_STOP;
 
 	mutex_lock(&ashmem_mutex);
 	list_for_each_entry_safe(range, next, &ashmem_lru_list, lru) {
@@ -374,17 +373,32 @@ static int ashmem_shrink(struct shrinker *s, struct shrink_control *sc)
 		range->purged = ASHMEM_WAS_PURGED;
 		lru_del(range);
 
-		sc->nr_to_scan -= range_size(range);
-		if (sc->nr_to_scan <= 0)
+		freed += range_size(range);
+		if (--sc->nr_to_scan <= 0)
 			break;
 	}
 	mutex_unlock(&ashmem_mutex);
+	return freed;
+}
 
+static unsigned long
+ashmem_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+	/*
+	 * note that lru_count is count of pages on the lru, not a count of
+	 * objects on the list. This means the scan function needs to return the
+	 * number of pages freed, not the number of objects scanned.
+	 */
 	return lru_count;
 }
 
 static struct shrinker ashmem_shrinker = {
-	.shrink = ashmem_shrink,
+	.count_objects = ashmem_shrink_count,
+	.scan_objects = ashmem_shrink_scan,
+	/*
+	 * XXX (dchinner): I wish people would comment on why they need on
+	 * significant changes to the default value here
+	 */
 	.seeks = DEFAULT_SEEKS * 4,
 };
 
@@ -690,11 +704,11 @@ static long ashmem_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		if (capable(CAP_SYS_ADMIN)) {
 			struct shrink_control sc = {
 				.gfp_mask = GFP_KERNEL,
-				.nr_to_scan = 0,
+				.nr_to_scan = LONG_MAX,
 			};
-			ret = ashmem_shrink(&ashmem_shrinker, &sc);
-			sc.nr_to_scan = ret;
-			ashmem_shrink(&ashmem_shrinker, &sc);
+
+			nodes_setall(sc.nodes_to_scan);
+			ashmem_shrink_scan(&ashmem_shrinker, &sc);
 		}
 		break;
 	}

drivers/staging/android/lowmemorykiller.c

@@ -66,11 +66,20 @@ static unsigned long lowmem_deathpending_timeout;
 			pr_info(x);			\
 	} while (0)
 
-static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
+static unsigned long lowmem_count(struct shrinker *s,
+				  struct shrink_control *sc)
+{
+	return global_page_state(NR_ACTIVE_ANON) +
+		global_page_state(NR_ACTIVE_FILE) +
+		global_page_state(NR_INACTIVE_ANON) +
+		global_page_state(NR_INACTIVE_FILE);
+}
+
+static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc)
 {
 	struct task_struct *tsk;
 	struct task_struct *selected = NULL;
-	int rem = 0;
+	unsigned long rem = 0;
 	int tasksize;
 	int i;
 	short min_score_adj = OOM_SCORE_ADJ_MAX + 1;
@@ -92,19 +101,17 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
 			break;
 		}
 	}
-	if (sc->nr_to_scan > 0)
-		lowmem_print(3, "lowmem_shrink %lu, %x, ofree %d %d, ma %hd\n",
-				sc->nr_to_scan, sc->gfp_mask, other_free,
-				other_file, min_score_adj);
-	rem = global_page_state(NR_ACTIVE_ANON) +
-		global_page_state(NR_ACTIVE_FILE) +
-		global_page_state(NR_INACTIVE_ANON) +
-		global_page_state(NR_INACTIVE_FILE);
-	if (sc->nr_to_scan <= 0 || min_score_adj == OOM_SCORE_ADJ_MAX + 1) {
-		lowmem_print(5, "lowmem_shrink %lu, %x, return %d\n",
-			     sc->nr_to_scan, sc->gfp_mask, rem);
-		return rem;
+
+	lowmem_print(3, "lowmem_scan %lu, %x, ofree %d %d, ma %hd\n",
+			sc->nr_to_scan, sc->gfp_mask, other_free,
+			other_file, min_score_adj);
+
+	if (min_score_adj == OOM_SCORE_ADJ_MAX + 1) {
+		lowmem_print(5, "lowmem_scan %lu, %x, return 0\n",
+			     sc->nr_to_scan, sc->gfp_mask);
+		return 0;
 	}
+
 	selected_oom_score_adj = min_score_adj;
 
 	rcu_read_lock();
@@ -154,16 +161,18 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
 		lowmem_deathpending_timeout = jiffies + HZ;
 		send_sig(SIGKILL, selected, 0);
 		set_tsk_thread_flag(selected, TIF_MEMDIE);
-		rem -= selected_tasksize;
+		rem += selected_tasksize;
 	}
-	lowmem_print(4, "lowmem_shrink %lu, %x, return %d\n",
+
+	lowmem_print(4, "lowmem_scan %lu, %x, return %lu\n",
 		     sc->nr_to_scan, sc->gfp_mask, rem);
 	rcu_read_unlock();
 	return rem;
 }
 
 static struct shrinker lowmem_shrinker = {
-	.shrink = lowmem_shrink,
+	.scan_objects = lowmem_scan,
+	.count_objects = lowmem_count,
 	.seeks = DEFAULT_SEEKS * 16
 };
 

drivers/staging/lustre/include/linux/libcfs/linux/linux-mem.h

@@ -79,42 +79,4 @@
 	do { __oldfs = get_fs(); set_fs(get_ds());} while(0)
 #define MMSPACE_CLOSE	       set_fs(__oldfs)
 
-/*
- * Shrinker
- */
-
-# define SHRINKER_ARGS(sc, nr_to_scan, gfp_mask)  \
-		       struct shrinker *shrinker, \
-		       struct shrink_control *sc
-# define shrink_param(sc, var) ((sc)->var)
-
-typedef int (*shrinker_t)(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask));
-
-static inline
-struct shrinker *set_shrinker(int seek, shrinker_t func)
-{
-	struct shrinker *s;
-
-	s = kmalloc(sizeof(*s), GFP_KERNEL);
-	if (s == NULL)
-		return (NULL);
-
-	s->shrink = func;
-	s->seeks = seek;
-
-	register_shrinker(s);
-
-	return s;
-}
-
-static inline
-void remove_shrinker(struct shrinker *shrinker)
-{
-	if (shrinker == NULL)
-		return;
-
-	unregister_shrinker(shrinker);
-	kfree(shrinker);
-}
-
 #endif /* __LINUX_CFS_MEM_H__ */

drivers/staging/lustre/lustre/ldlm/ldlm_pool.c

@@ -521,7 +521,7 @@ static int ldlm_cli_pool_shrink(struct ldlm_pool *pl,
 				int nr, unsigned int gfp_mask)
 {
 	struct ldlm_namespace *ns;
-	int canceled = 0, unused;
+	int unused;
 
 	ns = ldlm_pl2ns(pl);
 
@@ -540,14 +540,10 @@ static int ldlm_cli_pool_shrink(struct ldlm_pool *pl,
 	unused = ns->ns_nr_unused;
 	spin_unlock(&ns->ns_lock);
 
-	if (nr) {
-		canceled = ldlm_cancel_lru(ns, nr, LCF_ASYNC,
-					   LDLM_CANCEL_SHRINK);
-	}
-	/*
-	 * Return the number of potentially reclaimable locks.
-	 */
-	return ((unused - canceled) / 100) * sysctl_vfs_cache_pressure;
+	if (nr == 0)
+		return (unused / 100) * sysctl_vfs_cache_pressure;
+	else
+		return ldlm_cancel_lru(ns, nr, LCF_ASYNC, LDLM_CANCEL_SHRINK);
 }
 
 struct ldlm_pool_ops ldlm_srv_pool_ops = {
@@ -601,9 +597,10 @@ int ldlm_pool_recalc(struct ldlm_pool *pl)
 	return recalc_interval_sec;
 }
 
-/**
+/*
  * Pool shrink wrapper. Will call either client or server pool recalc callback
- * depending what pool \a pl is used.
+ * depending what pool pl is used. When nr == 0, just return the number of
+ * freeable locks. Otherwise, return the number of canceled locks.
  */
 int ldlm_pool_shrink(struct ldlm_pool *pl, int nr,
 		     unsigned int gfp_mask)
@@ -1017,29 +1014,24 @@ static int ldlm_pool_granted(struct ldlm_pool *pl)
 }
 
 static struct ptlrpc_thread *ldlm_pools_thread;
-static struct shrinker *ldlm_pools_srv_shrinker;
-static struct shrinker *ldlm_pools_cli_shrinker;
 static struct completion ldlm_pools_comp;
 
 /*
- * Cancel \a nr locks from all namespaces (if possible). Returns number of
- * cached locks after shrink is finished. All namespaces are asked to
- * cancel approximately equal amount of locks to keep balancing.
+ * count locks from all namespaces (if possible). Returns number of
+ * cached locks.
  */
-static int ldlm_pools_shrink(ldlm_side_t client, int nr,
-			     unsigned int gfp_mask)
+static unsigned long ldlm_pools_count(ldlm_side_t client, unsigned int gfp_mask)
 {
-	int total = 0, cached = 0, nr_ns;
+	int total = 0, nr_ns;
 	struct ldlm_namespace *ns;
 	struct ldlm_namespace *ns_old = NULL; /* loop detection */
 	void *cookie;
 
-	if (client == LDLM_NAMESPACE_CLIENT && nr != 0 &&
-	    !(gfp_mask & __GFP_FS))
-		return -1;
+	if (client == LDLM_NAMESPACE_CLIENT && !(gfp_mask & __GFP_FS))
+		return 0;
 
-	CDEBUG(D_DLMTRACE, "Request to shrink %d %s locks from all pools\n",
-	       nr, client == LDLM_NAMESPACE_CLIENT ? "client" : "server");
+	CDEBUG(D_DLMTRACE, "Request to count %s locks from all pools\n",
+	       client == LDLM_NAMESPACE_CLIENT ? "client" : "server");
 
 	cookie = cl_env_reenter();
 
@@ -1047,8 +1039,7 @@ static int ldlm_pools_shrink(ldlm_side_t client, int nr,
 	 * Find out how many resources we may release.
 	 */
 	for (nr_ns = ldlm_namespace_nr_read(client);
-	     nr_ns > 0; nr_ns--)
-	{
+	     nr_ns > 0; nr_ns--) {
 		mutex_lock(ldlm_namespace_lock(client));
 		if (list_empty(ldlm_namespace_list(client))) {
 			mutex_unlock(ldlm_namespace_lock(client));
@@ -1078,17 +1069,27 @@ static int ldlm_pools_shrink(ldlm_side_t client, int nr,
 		ldlm_namespace_put(ns);
 	}
 
-	if (nr == 0 || total == 0) {
-		cl_env_reexit(cookie);
-		return total;
-	}
+	cl_env_reexit(cookie);
+	return total;
+}
+
+static unsigned long ldlm_pools_scan(ldlm_side_t client, int nr, unsigned int gfp_mask)
+{
+	unsigned long freed = 0;
+	int tmp, nr_ns;
+	struct ldlm_namespace *ns;
+	void *cookie;
+
+	if (client == LDLM_NAMESPACE_CLIENT && !(gfp_mask & __GFP_FS))
+		return -1;
+
+	cookie = cl_env_reenter();
 
 	/*
-	 * Shrink at least ldlm_namespace_nr(client) namespaces.
+	 * Shrink at least ldlm_namespace_nr_read(client) namespaces.
 	 */
-	for (nr_ns = ldlm_namespace_nr_read(client) - nr_ns;
-	     nr_ns > 0; nr_ns--)
-	{
+	for (tmp = nr_ns = ldlm_namespace_nr_read(client);
+	     tmp > 0; tmp--) {
 		int cancel, nr_locks;
 
 		/*
@@ -1097,12 +1098,6 @@ static int ldlm_pools_shrink(ldlm_side_t client, int nr,
 		mutex_lock(ldlm_namespace_lock(client));
 		if (list_empty(ldlm_namespace_list(client))) {
 			mutex_unlock(ldlm_namespace_lock(client));
-			/*
-			 * If list is empty, we can't return any @cached > 0,
-			 * that probably would cause needless shrinker
-			 * call.
-			 */
-			cached = 0;
 			break;
 		}
 		ns = ldlm_namespace_first_locked(client);
@@ -1111,29 +1106,42 @@ static int ldlm_pools_shrink(ldlm_side_t client, int nr,
 		mutex_unlock(ldlm_namespace_lock(client));
 
 		nr_locks = ldlm_pool_granted(&ns->ns_pool);
-		cancel = 1 + nr_locks * nr / total;
-		ldlm_pool_shrink(&ns->ns_pool, cancel, gfp_mask);
-		cached += ldlm_pool_granted(&ns->ns_pool);
+		/*
+		 * We use to shrink propotionally but with new shrinker API,
+		 * we lost the total number of freeable locks.
+		 */
+		cancel = 1 + min_t(int, nr_locks, nr / nr_ns);
+		freed += ldlm_pool_shrink(&ns->ns_pool, cancel, gfp_mask);
 		ldlm_namespace_put(ns);
 	}
 	cl_env_reexit(cookie);
-	/* we only decrease the SLV in server pools shrinker, return -1 to
-	 * kernel to avoid needless loop. LU-1128 */
-	return (client == LDLM_NAMESPACE_SERVER) ? -1 : cached;
+	/*
+	 * we only decrease the SLV in server pools shrinker, return
+	 * SHRINK_STOP to kernel to avoid needless loop. LU-1128
+	 */
+	return (client == LDLM_NAMESPACE_SERVER) ? SHRINK_STOP : freed;
+}
+
+static unsigned long ldlm_pools_srv_count(struct shrinker *s, struct shrink_control *sc)
+{
+	return ldlm_pools_count(LDLM_NAMESPACE_SERVER, sc->gfp_mask);
 }
 
-static int ldlm_pools_srv_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
+static unsigned long ldlm_pools_srv_scan(struct shrinker *s, struct shrink_control *sc)
 {
-	return ldlm_pools_shrink(LDLM_NAMESPACE_SERVER,
-				 shrink_param(sc, nr_to_scan),
-				 shrink_param(sc, gfp_mask));
+	return ldlm_pools_scan(LDLM_NAMESPACE_SERVER, sc->nr_to_scan,
+			       sc->gfp_mask);
 }
 
-static int ldlm_pools_cli_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
+static unsigned long ldlm_pools_cli_count(struct shrinker *s, struct shrink_control *sc)
 {
-	return ldlm_pools_shrink(LDLM_NAMESPACE_CLIENT,
-				 shrink_param(sc, nr_to_scan),
-				 shrink_param(sc, gfp_mask));
+	return ldlm_pools_count(LDLM_NAMESPACE_CLIENT, sc->gfp_mask);
+}
+
+static unsigned long ldlm_pools_cli_scan(struct shrinker *s, struct shrink_control *sc)
+{
+	return ldlm_pools_scan(LDLM_NAMESPACE_CLIENT, sc->nr_to_scan,
+			       sc->gfp_mask);
 }
 
 int ldlm_pools_recalc(ldlm_side_t client)
@@ -1216,7 +1224,7 @@ int ldlm_pools_recalc(ldlm_side_t client)
 	}
 
 	/*
-	 * Recalc at least ldlm_namespace_nr(client) namespaces.
+	 * Recalc at least ldlm_namespace_nr_read(client) namespaces.
 	 */
 	for (nr = ldlm_namespace_nr_read(client); nr > 0; nr--) {
 		int     skip;
@@ -1383,18 +1391,26 @@ static void ldlm_pools_thread_stop(void)
 	ldlm_pools_thread = NULL;
 }
 
+static struct shrinker ldlm_pools_srv_shrinker = {
+	.count_objects	= ldlm_pools_srv_count,
+	.scan_objects	= ldlm_pools_srv_scan,
+	.seeks		= DEFAULT_SEEKS,
+};
+
+static struct shrinker ldlm_pools_cli_shrinker = {
+	.count_objects	= ldlm_pools_cli_count,
+	.scan_objects	= ldlm_pools_cli_scan,
+	.seeks		= DEFAULT_SEEKS,
+};
+
 int ldlm_pools_init(void)
 {
 	int rc;
 
 	rc = ldlm_pools_thread_start();
 	if (rc == 0) {
-		ldlm_pools_srv_shrinker =
-			set_shrinker(DEFAULT_SEEKS,
-					 ldlm_pools_srv_shrink);
-		ldlm_pools_cli_shrinker =
-			set_shrinker(DEFAULT_SEEKS,
-					 ldlm_pools_cli_shrink);
+		register_shrinker(&ldlm_pools_srv_shrinker);
+		register_shrinker(&ldlm_pools_cli_shrinker);
 	}
 	return rc;
 }
@@ -1402,14 +1418,8 @@ EXPORT_SYMBOL(ldlm_pools_init);
 
 void ldlm_pools_fini(void)
 {
-	if (ldlm_pools_srv_shrinker != NULL) {
-		remove_shrinker(ldlm_pools_srv_shrinker);
-		ldlm_pools_srv_shrinker = NULL;
-	}
-	if (ldlm_pools_cli_shrinker != NULL) {
-		remove_shrinker(ldlm_pools_cli_shrinker);
-		ldlm_pools_cli_shrinker = NULL;
-	}
+	unregister_shrinker(&ldlm_pools_srv_shrinker);
+	unregister_shrinker(&ldlm_pools_cli_shrinker);
 	ldlm_pools_thread_stop();
 }
 EXPORT_SYMBOL(ldlm_pools_fini);

drivers/staging/lustre/lustre/obdclass/lu_object.c

@@ -1779,7 +1779,6 @@ int lu_env_refill_by_tags(struct lu_env *env, __u32 ctags,
 }
 EXPORT_SYMBOL(lu_env_refill_by_tags);
 
-static struct shrinker *lu_site_shrinker = NULL;
 
 typedef struct lu_site_stats{
 	unsigned	lss_populated;
@@ -1835,61 +1834,68 @@ static void lu_site_stats_get(cfs_hash_t *hs,
  * objects without taking the  lu_sites_guard lock, but this is not
  * possible in the current implementation.
  */
-static int lu_cache_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
+static unsigned long lu_cache_shrink_count(struct shrinker *sk,
+					   struct shrink_control *sc)
 {
 	lu_site_stats_t stats;
 	struct lu_site *s;
 	struct lu_site *tmp;
-	int cached = 0;
-	int remain = shrink_param(sc, nr_to_scan);
-	LIST_HEAD(splice);
-
-	if (!(shrink_param(sc, gfp_mask) & __GFP_FS)) {
-		if (remain != 0)
-			return -1;
-		else
-			/* We must not take the lu_sites_guard lock when
-			 * __GFP_FS is *not* set because of the deadlock
-			 * possibility detailed above. Additionally,
-			 * since we cannot determine the number of
-			 * objects in the cache without taking this
-			 * lock, we're in a particularly tough spot. As
-			 * a result, we'll just lie and say our cache is
-			 * empty. This _should_ be ok, as we can't
-			 * reclaim objects when __GFP_FS is *not* set
-			 * anyways.
-			 */
-			return 0;
-	}
+	unsigned long cached = 0;
 
-	CDEBUG(D_INODE, "Shrink %d objects\n", remain);
+	if (!(sc->gfp_mask & __GFP_FS))
+		return 0;
 
 	mutex_lock(&lu_sites_guard);
 	list_for_each_entry_safe(s, tmp, &lu_sites, ls_linkage) {
-		if (shrink_param(sc, nr_to_scan) != 0) {
-			remain = lu_site_purge(&lu_shrink_env, s, remain);
-			/*
-			 * Move just shrunk site to the tail of site list to
-			 * assure shrinking fairness.
-			 */
-			list_move_tail(&s->ls_linkage, &splice);
-		}
-
 		memset(&stats, 0, sizeof(stats));
 		lu_site_stats_get(s->ls_obj_hash, &stats, 0);
 		cached += stats.lss_total - stats.lss_busy;
-		if (shrink_param(sc, nr_to_scan) && remain <= 0)
-			break;
 	}
-	list_splice(&splice, lu_sites.prev);
 	mutex_unlock(&lu_sites_guard);
 
 	cached = (cached / 100) * sysctl_vfs_cache_pressure;
-	if (shrink_param(sc, nr_to_scan) == 0)
-		CDEBUG(D_INODE, "%d objects cached\n", cached);
+	CDEBUG(D_INODE, "%ld objects cached\n", cached);
 	return cached;
 }
 
+static unsigned long lu_cache_shrink_scan(struct shrinker *sk,
+					  struct shrink_control *sc)
+{
+	struct lu_site *s;
+	struct lu_site *tmp;
+	unsigned long remain = sc->nr_to_scan, freed = 0;
+	LIST_HEAD(splice);
+
+	if (!(sc->gfp_mask & __GFP_FS))
+		/* We must not take the lu_sites_guard lock when
+		 * __GFP_FS is *not* set because of the deadlock
+		 * possibility detailed above. Additionally,
+		 * since we cannot determine the number of
+		 * objects in the cache without taking this
+		 * lock, we're in a particularly tough spot. As
+		 * a result, we'll just lie and say our cache is
+		 * empty. This _should_ be ok, as we can't
+		 * reclaim objects when __GFP_FS is *not* set
+		 * anyways.
+		 */
+		return SHRINK_STOP;
+
+	mutex_lock(&lu_sites_guard);
+	list_for_each_entry_safe(s, tmp, &lu_sites, ls_linkage) {
+		freed = lu_site_purge(&lu_shrink_env, s, remain);
+		remain -= freed;
+		/*
+		 * Move just shrunk site to the tail of site list to
+		 * assure shrinking fairness.
+		 */
+		list_move_tail(&s->ls_linkage, &splice);
+	}
+	list_splice(&splice, lu_sites.prev);
+	mutex_unlock(&lu_sites_guard);
+
+	return sc->nr_to_scan - remain;
+}
+
 /*
  * Debugging stuff.
  */
@@ -1913,6 +1919,12 @@ int lu_printk_printer(const struct lu_env *env,
 	return 0;
 }
 
+static struct shrinker lu_site_shrinker = {
+	.count_objects	= lu_cache_shrink_count,
+	.scan_objects	= lu_cache_shrink_scan,
+	.seeks 		= DEFAULT_SEEKS,
+};
+
 /**
  * Initialization of global lu_* data.
  */
@@ -1947,9 +1959,7 @@ int lu_global_init(void)
 	 * inode, one for ea. Unfortunately setting this high value results in
 	 * lu_object/inode cache consuming all the memory.
 	 */
-	lu_site_shrinker = set_shrinker(DEFAULT_SEEKS, lu_cache_shrink);
-	if (lu_site_shrinker == NULL)
-		return -ENOMEM;
+	register_shrinker(&lu_site_shrinker);
 
 	return result;
 }
@@ -1959,11 +1969,7 @@ int lu_global_init(void)
  */
 void lu_global_fini(void)
 {
-	if (lu_site_shrinker != NULL) {
-		remove_shrinker(lu_site_shrinker);
-		lu_site_shrinker = NULL;
-	}
-
+	unregister_shrinker(&lu_site_shrinker);
 	lu_context_key_degister(&lu_global_key);
 
 	/*

drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c

@@ -120,13 +120,6 @@ static struct ptlrpc_enc_page_pool {
 	struct page    ***epp_pools;
 } page_pools;
 
-/*
- * memory shrinker
- */
-const int pools_shrinker_seeks = DEFAULT_SEEKS;
-static struct shrinker *pools_shrinker = NULL;
-
-
 /*
  * /proc/fs/lustre/sptlrpc/encrypt_page_pools
  */
@@ -226,30 +219,46 @@ static void enc_pools_release_free_pages(long npages)
 }
 
 /*
- * could be called frequently for query (@nr_to_scan == 0).
  * we try to keep at least PTLRPC_MAX_BRW_PAGES pages in the pool.
  */
-static int enc_pools_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
+static unsigned long enc_pools_shrink_count(struct shrinker *s,
+					    struct shrink_control *sc)
 {
-	if (unlikely(shrink_param(sc, nr_to_scan) != 0)) {
+	/*
+	 * if no pool access for a long time, we consider it's fully idle.
+	 * a little race here is fine.
+	 */
+	if (unlikely(cfs_time_current_sec() - page_pools.epp_last_access >
+		     CACHE_QUIESCENT_PERIOD)) {
 		spin_lock(&page_pools.epp_lock);
-		shrink_param(sc, nr_to_scan) = min_t(unsigned long,
-						   shrink_param(sc, nr_to_scan),
-						   page_pools.epp_free_pages -
-						   PTLRPC_MAX_BRW_PAGES);
-		if (shrink_param(sc, nr_to_scan) > 0) {
-			enc_pools_release_free_pages(shrink_param(sc,
-								  nr_to_scan));
-			CDEBUG(D_SEC, "released %ld pages, %ld left\n",
-			       (long)shrink_param(sc, nr_to_scan),
-			       page_pools.epp_free_pages);
-
-			page_pools.epp_st_shrinks++;
-			page_pools.epp_last_shrink = cfs_time_current_sec();
-		}
+		page_pools.epp_idle_idx = IDLE_IDX_MAX;
 		spin_unlock(&page_pools.epp_lock);
 	}
 
+	LASSERT(page_pools.epp_idle_idx <= IDLE_IDX_MAX);
+	return max((int)page_pools.epp_free_pages - PTLRPC_MAX_BRW_PAGES, 0) *
+		(IDLE_IDX_MAX - page_pools.epp_idle_idx) / IDLE_IDX_MAX;
+}
+
+/*
+ * we try to keep at least PTLRPC_MAX_BRW_PAGES pages in the pool.
+ */
+static unsigned long enc_pools_shrink_scan(struct shrinker *s,
+					   struct shrink_control *sc)
+{
+	spin_lock(&page_pools.epp_lock);
+	sc->nr_to_scan = min_t(unsigned long, sc->nr_to_scan,
+			      page_pools.epp_free_pages - PTLRPC_MAX_BRW_PAGES);
+	if (sc->nr_to_scan > 0) {
+		enc_pools_release_free_pages(sc->nr_to_scan);
+		CDEBUG(D_SEC, "released %ld pages, %ld left\n",
+		       (long)sc->nr_to_scan, page_pools.epp_free_pages);
+
+		page_pools.epp_st_shrinks++;
+		page_pools.epp_last_shrink = cfs_time_current_sec();
+	}
+	spin_unlock(&page_pools.epp_lock);
+
 	/*
 	 * if no pool access for a long time, we consider it's fully idle.
 	 * a little race here is fine.
@@ -262,8 +271,7 @@ static int enc_pools_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
 	}
 
 	LASSERT(page_pools.epp_idle_idx <= IDLE_IDX_MAX);
-	return max((int)page_pools.epp_free_pages - PTLRPC_MAX_BRW_PAGES, 0) *
-		(IDLE_IDX_MAX - page_pools.epp_idle_idx) / IDLE_IDX_MAX;
+	return sc->nr_to_scan;
 }
 
 static inline
@@ -699,6 +707,12 @@ static inline void enc_pools_free(void)
 		       sizeof(*page_pools.epp_pools));
 }
 
+static struct shrinker pools_shrinker = {
+	.count_objects	= enc_pools_shrink_count,
+	.scan_objects	= enc_pools_shrink_scan,
+	.seeks		= DEFAULT_SEEKS,
+};
+
 int sptlrpc_enc_pool_init(void)
 {
 	/*
@@ -736,12 +750,7 @@ int sptlrpc_enc_pool_init(void)
 	if (page_pools.epp_pools == NULL)
 		return -ENOMEM;
 
-	pools_shrinker = set_shrinker(pools_shrinker_seeks,
-					  enc_pools_shrink);
-	if (pools_shrinker == NULL) {
-		enc_pools_free();
-		return -ENOMEM;
-	}
+	register_shrinker(&pools_shrinker);
 
 	return 0;
 }
@@ -750,11 +759,10 @@ void sptlrpc_enc_pool_fini(void)
 {
 	unsigned long cleaned, npools;
 
-	LASSERT(pools_shrinker);
 	LASSERT(page_pools.epp_pools);
 	LASSERT(page_pools.epp_total_pages == page_pools.epp_free_pages);
 
-	remove_shrinker(pools_shrinker);
+	unregister_shrinker(&pools_shrinker);
 
 	npools = npages_to_npools(page_pools.epp_total_pages);
 	cleaned = enc_pools_cleanup(page_pools.epp_pools, npools);

fs/dcache.c

@@ -37,6 +37,7 @@
 #include <linux/rculist_bl.h>
 #include <linux/prefetch.h>
 #include <linux/ratelimit.h>
+#include <linux/list_lru.h>
 #include "internal.h"
 #include "mount.h"
 
@@ -48,7 +49,7 @@
  *   - the dcache hash table
  * s_anon bl list spinlock protects:
  *   - the s_anon list (see __d_drop)
- * dcache_lru_lock protects:
+ * dentry->d_sb->s_dentry_lru_lock protects:
  *   - the dcache lru lists and counters
  * d_lock protects:
  *   - d_flags
@@ -63,7 +64,7 @@
  * Ordering:
  * dentry->d_inode->i_lock
  *   dentry->d_lock
- *     dcache_lru_lock
+ *     dentry->d_sb->s_dentry_lru_lock
  *     dcache_hash_bucket lock
  *     s_anon lock
  *
@@ -81,7 +82,6 @@
 int sysctl_vfs_cache_pressure __read_mostly = 100;
 EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure);
 
-static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_lru_lock);
 __cacheline_aligned_in_smp DEFINE_SEQLOCK(rename_lock);
 
 EXPORT_SYMBOL(rename_lock);
@@ -146,23 +146,47 @@ struct dentry_stat_t dentry_stat = {
 	.age_limit = 45,
 };
 
-static DEFINE_PER_CPU(unsigned int, nr_dentry);
+static DEFINE_PER_CPU(long, nr_dentry);
+static DEFINE_PER_CPU(long, nr_dentry_unused);
 
 #if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS)
-static int get_nr_dentry(void)
+
+/*
+ * Here we resort to our own counters instead of using generic per-cpu counters
+ * for consistency with what the vfs inode code does. We are expected to harvest
+ * better code and performance by having our own specialized counters.
+ *
+ * Please note that the loop is done over all possible CPUs, not over all online
+ * CPUs. The reason for this is that we don't want to play games with CPUs going
+ * on and off. If one of them goes off, we will just keep their counters.
+ *
+ * glommer: See cffbc8a for details, and if you ever intend to change this,
+ * please update all vfs counters to match.
+ */
+static long get_nr_dentry(void)
 {
 	int i;
-	int sum = 0;
+	long sum = 0;
 	for_each_possible_cpu(i)
 		sum += per_cpu(nr_dentry, i);
 	return sum < 0 ? 0 : sum;
 }
 
+static long get_nr_dentry_unused(void)
+{
+	int i;
+	long sum = 0;
+	for_each_possible_cpu(i)
+		sum += per_cpu(nr_dentry_unused, i);
+	return sum < 0 ? 0 : sum;
+}
+
 int proc_nr_dentry(ctl_table *table, int write, void __user *buffer,
 		   size_t *lenp, loff_t *ppos)
 {
 	dentry_stat.nr_dentry = get_nr_dentry();
-	return proc_dointvec(table, write, buffer, lenp, ppos);
+	dentry_stat.nr_unused = get_nr_dentry_unused();
+	return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 }
 #endif
 
@@ -333,52 +357,35 @@ static void dentry_unlink_inode(struct dentry * dentry)
 }
 
 /*
- * dentry_lru_(add|del|prune|move_tail) must be called with d_lock held.
+ * dentry_lru_(add|del)_list) must be called with d_lock held.
  */
 static void dentry_lru_add(struct dentry *dentry)
 {
 	if (unlikely(!(dentry->d_flags & DCACHE_LRU_LIST))) {
-		spin_lock(&dcache_lru_lock);
+		if (list_lru_add(&dentry->d_sb->s_dentry_lru, &dentry->d_lru))
+			this_cpu_inc(nr_dentry_unused);
 		dentry->d_flags |= DCACHE_LRU_LIST;
-		list_add(&dentry->d_lru, &dentry->d_sb->s_dentry_lru);
-		dentry->d_sb->s_nr_dentry_unused++;
-		dentry_stat.nr_unused++;
-		spin_unlock(&dcache_lru_lock);
 	}
 }
 
-static void __dentry_lru_del(struct dentry *dentry)
-{
-	list_del_init(&dentry->d_lru);
-	dentry->d_flags &= ~(DCACHE_SHRINK_LIST | DCACHE_LRU_LIST);
-	dentry->d_sb->s_nr_dentry_unused--;
-	dentry_stat.nr_unused--;
-}
-
 /*
  * Remove a dentry with references from the LRU.
+ *
+ * If we are on the shrink list, then we can get to try_prune_one_dentry() and
+ * lose our last reference through the parent walk. In this case, we need to
+ * remove ourselves from the shrink list, not the LRU.
  */
 static void dentry_lru_del(struct dentry *dentry)
 {
-	if (!list_empty(&dentry->d_lru)) {
-		spin_lock(&dcache_lru_lock);
-		__dentry_lru_del(dentry);
-		spin_unlock(&dcache_lru_lock);
+	if (dentry->d_flags & DCACHE_SHRINK_LIST) {
+		list_del_init(&dentry->d_lru);
+		dentry->d_flags &= ~DCACHE_SHRINK_LIST;
+		return;
 	}
-}
 
-static void dentry_lru_move_list(struct dentry *dentry, struct list_head *list)
-{
-	spin_lock(&dcache_lru_lock);
-	if (list_empty(&dentry->d_lru)) {
-		dentry->d_flags |= DCACHE_LRU_LIST;
-		list_add_tail(&dentry->d_lru, list);
-		dentry->d_sb->s_nr_dentry_unused++;
-		dentry_stat.nr_unused++;
-	} else {
-		list_move_tail(&dentry->d_lru, list);
-	}
-	spin_unlock(&dcache_lru_lock);
+	if (list_lru_del(&dentry->d_sb->s_dentry_lru, &dentry->d_lru))
+		this_cpu_dec(nr_dentry_unused);
+	dentry->d_flags &= ~DCACHE_LRU_LIST;
 }
 
 /**
@@ -474,7 +481,8 @@ EXPORT_SYMBOL(d_drop);
  * If ref is non-zero, then decrement the refcount too.
  * Returns dentry requiring refcount drop, or NULL if we're done.
  */
-static inline struct dentry *dentry_kill(struct dentry *dentry)
+static inline struct dentry *
+dentry_kill(struct dentry *dentry, int unlock_on_failure)
 	__releases(dentry->d_lock)
 {
 	struct inode *inode;
@@ -483,8 +491,10 @@ static inline struct dentry *dentry_kill(struct dentry *dentry)
 	inode = dentry->d_inode;
 	if (inode && !spin_trylock(&inode->i_lock)) {
 relock:
-		spin_unlock(&dentry->d_lock);
-		cpu_relax();
+		if (unlock_on_failure) {
+			spin_unlock(&dentry->d_lock);
+			cpu_relax();
+		}
 		return dentry; /* try again with same dentry */
 	}
 	if (IS_ROOT(dentry))
@@ -567,7 +577,7 @@ repeat:
 	return;
 
 kill_it:
-	dentry = dentry_kill(dentry);
+	dentry = dentry_kill(dentry, 1);
 	if (dentry)
 		goto repeat;
 }
@@ -787,12 +797,12 @@ EXPORT_SYMBOL(d_prune_aliases);
  *
  * This may fail if locks cannot be acquired no problem, just try again.
  */
-static void try_prune_one_dentry(struct dentry *dentry)
+static struct dentry * try_prune_one_dentry(struct dentry *dentry)
 	__releases(dentry->d_lock)
 {
 	struct dentry *parent;
 
-	parent = dentry_kill(dentry);
+	parent = dentry_kill(dentry, 0);
 	/*
 	 * If dentry_kill returns NULL, we have nothing more to do.
 	 * if it returns the same dentry, trylocks failed. In either
@@ -804,17 +814,18 @@ static void try_prune_one_dentry(struct dentry *dentry)
 	 * fragmentation.
 	 */
 	if (!parent)
-		return;
+		return NULL;
 	if (parent == dentry)
-		return;
+		return dentry;
 
 	/* Prune ancestors. */
 	dentry = parent;
 	while (dentry) {
 		if (lockref_put_or_lock(&dentry->d_lockref))
-			return;
-		dentry = dentry_kill(dentry);
+			return NULL;
+		dentry = dentry_kill(dentry, 1);
 	}
+	return NULL;
 }
 
 static void shrink_dentry_list(struct list_head *list)
@@ -832,77 +843,144 @@ static void shrink_dentry_list(struct list_head *list)
 			continue;
 		}
 
+		/*
+		 * The dispose list is isolated and dentries are not accounted
+		 * to the LRU here, so we can simply remove it from the list
+		 * here regardless of whether it is referenced or not.
+		 */
+		list_del_init(&dentry->d_lru);
+		dentry->d_flags &= ~DCACHE_SHRINK_LIST;
+
 		/*
 		 * We found an inuse dentry which was not removed from
-		 * the LRU because of laziness during lookup.  Do not free
-		 * it - just keep it off the LRU list.
+		 * the LRU because of laziness during lookup. Do not free it.
 		 */
 		if (dentry->d_lockref.count) {
-			dentry_lru_del(dentry);
 			spin_unlock(&dentry->d_lock);
 			continue;
 		}
-
 		rcu_read_unlock();
 
-		try_prune_one_dentry(dentry);
+		dentry = try_prune_one_dentry(dentry);
 
 		rcu_read_lock();
+		if (dentry) {
+			dentry->d_flags |= DCACHE_SHRINK_LIST;
+			list_add(&dentry->d_lru, list);
+			spin_unlock(&dentry->d_lock);
+		}
 	}
 	rcu_read_unlock();
 }
 
+static enum lru_status
+dentry_lru_isolate(struct list_head *item, spinlock_t *lru_lock, void *arg)
+{
+	struct list_head *freeable = arg;
+	struct dentry	*dentry = container_of(item, struct dentry, d_lru);
+
+
+	/*
+	 * we are inverting the lru lock/dentry->d_lock here,
+	 * so use a trylock. If we fail to get the lock, just skip
+	 * it
+	 */
+	if (!spin_trylock(&dentry->d_lock))
+		return LRU_SKIP;
+
+	/*
+	 * Referenced dentries are still in use. If they have active
+	 * counts, just remove them from the LRU. Otherwise give them
+	 * another pass through the LRU.
+	 */
+	if (dentry->d_lockref.count) {
+		list_del_init(&dentry->d_lru);
+		spin_unlock(&dentry->d_lock);
+		return LRU_REMOVED;
+	}
+
+	if (dentry->d_flags & DCACHE_REFERENCED) {
+		dentry->d_flags &= ~DCACHE_REFERENCED;
+		spin_unlock(&dentry->d_lock);
+
+		/*
+		 * The list move itself will be made by the common LRU code. At
+		 * this point, we've dropped the dentry->d_lock but keep the
+		 * lru lock. This is safe to do, since every list movement is
+		 * protected by the lru lock even if both locks are held.
+		 *
+		 * This is guaranteed by the fact that all LRU management
+		 * functions are intermediated by the LRU API calls like
+		 * list_lru_add and list_lru_del. List movement in this file
+		 * only ever occur through this functions or through callbacks
+		 * like this one, that are called from the LRU API.
+		 *
+		 * The only exceptions to this are functions like
+		 * shrink_dentry_list, and code that first checks for the
+		 * DCACHE_SHRINK_LIST flag.  Those are guaranteed to be
+		 * operating only with stack provided lists after they are
+		 * properly isolated from the main list.  It is thus, always a
+		 * local access.
+		 */
+		return LRU_ROTATE;
+	}
+
+	dentry->d_flags |= DCACHE_SHRINK_LIST;
+	list_move_tail(&dentry->d_lru, freeable);
+	this_cpu_dec(nr_dentry_unused);
+	spin_unlock(&dentry->d_lock);
+
+	return LRU_REMOVED;
+}
+
 /**
  * prune_dcache_sb - shrink the dcache
  * @sb: superblock
- * @count: number of entries to try to free
+ * @nr_to_scan : number of entries to try to free
+ * @nid: which node to scan for freeable entities
  *
- * Attempt to shrink the superblock dcache LRU by @count entries. This is
+ * Attempt to shrink the superblock dcache LRU by @nr_to_scan entries. This is
  * done when we need more memory an called from the superblock shrinker
  * function.
  *
  * This function may fail to free any resources if all the dentries are in
  * use.
  */
-void prune_dcache_sb(struct super_block *sb, int count)
+long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan,
+		     int nid)
 {
-	struct dentry *dentry;
-	LIST_HEAD(referenced);
-	LIST_HEAD(tmp);
+	LIST_HEAD(dispose);
+	long freed;
 
-relock:
-	spin_lock(&dcache_lru_lock);
-	while (!list_empty(&sb->s_dentry_lru)) {
-		dentry = list_entry(sb->s_dentry_lru.prev,
-				struct dentry, d_lru);
-		BUG_ON(dentry->d_sb != sb);
-
-		if (!spin_trylock(&dentry->d_lock)) {
-			spin_unlock(&dcache_lru_lock);
-			cpu_relax();
-			goto relock;
-		}
+	freed = list_lru_walk_node(&sb->s_dentry_lru, nid, dentry_lru_isolate,
+				       &dispose, &nr_to_scan);
+	shrink_dentry_list(&dispose);
+	return freed;
+}
 
-		if (dentry->d_flags & DCACHE_REFERENCED) {
-			dentry->d_flags &= ~DCACHE_REFERENCED;
-			list_move(&dentry->d_lru, &referenced);
-			spin_unlock(&dentry->d_lock);
-		} else {
-			list_move_tail(&dentry->d_lru, &tmp);
-			dentry->d_flags |= DCACHE_SHRINK_LIST;
-			spin_unlock(&dentry->d_lock);
-			if (!--count)
-				break;
-		}
-		cond_resched_lock(&dcache_lru_lock);
-	}
-	if (!list_empty(&referenced))
-		list_splice(&referenced, &sb->s_dentry_lru);
-	spin_unlock(&dcache_lru_lock);
+static enum lru_status dentry_lru_isolate_shrink(struct list_head *item,
+						spinlock_t *lru_lock, void *arg)
+{
+	struct list_head *freeable = arg;
+	struct dentry	*dentry = container_of(item, struct dentry, d_lru);
 
-	shrink_dentry_list(&tmp);
+	/*
+	 * we are inverting the lru lock/dentry->d_lock here,
+	 * so use a trylock. If we fail to get the lock, just skip
+	 * it
+	 */
+	if (!spin_trylock(&dentry->d_lock))
+		return LRU_SKIP;
+
+	dentry->d_flags |= DCACHE_SHRINK_LIST;
+	list_move_tail(&dentry->d_lru, freeable);
+	this_cpu_dec(nr_dentry_unused);
+	spin_unlock(&dentry->d_lock);
+
+	return LRU_REMOVED;
 }
 
+
 /**
  * shrink_dcache_sb - shrink dcache for a superblock
  * @sb: superblock
@@ -912,16 +990,17 @@ relock:
  */
 void shrink_dcache_sb(struct super_block *sb)
 {
-	LIST_HEAD(tmp);
+	long freed;
 
-	spin_lock(&dcache_lru_lock);
-	while (!list_empty(&sb->s_dentry_lru)) {
-		list_splice_init(&sb->s_dentry_lru, &tmp);
-		spin_unlock(&dcache_lru_lock);
-		shrink_dentry_list(&tmp);
-		spin_lock(&dcache_lru_lock);
-	}
-	spin_unlock(&dcache_lru_lock);
+	do {
+		LIST_HEAD(dispose);
+
+		freed = list_lru_walk(&sb->s_dentry_lru,
+			dentry_lru_isolate_shrink, &dispose, UINT_MAX);
+
+		this_cpu_sub(nr_dentry_unused, freed);
+		shrink_dentry_list(&dispose);
+	} while (freed > 0);
 }
 EXPORT_SYMBOL(shrink_dcache_sb);
 
@@ -1283,7 +1362,8 @@ static enum d_walk_ret select_collect(void *_data, struct dentry *dentry)
 	if (dentry->d_lockref.count) {
 		dentry_lru_del(dentry);
 	} else if (!(dentry->d_flags & DCACHE_SHRINK_LIST)) {
-		dentry_lru_move_list(dentry, &data->dispose);
+		dentry_lru_del(dentry);
+		list_add_tail(&dentry->d_lru, &data->dispose);
 		dentry->d_flags |= DCACHE_SHRINK_LIST;
 		data->found++;
 		ret = D_WALK_NORETRY;

fs/drop_caches.c

@@ -44,6 +44,7 @@ static void drop_slab(void)
 		.gfp_mask = GFP_KERNEL,
 	};
 
+	nodes_setall(shrink.nodes_to_scan);
 	do {
 		nr_objects = shrink_slab(&shrink, 1000, 1000);
 	} while (nr_objects > 10);

fs/ext4/extents_status.c

@@ -931,13 +931,15 @@ static int __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
 	struct ext4_inode_info *ei;
 	struct list_head *cur, *tmp;
 	LIST_HEAD(skipped);
-	int ret, nr_shrunk = 0;
+	int nr_shrunk = 0;
 	int retried = 0, skip_precached = 1, nr_skipped = 0;
 
 	spin_lock(&sbi->s_es_lru_lock);
 
 retry:
 	list_for_each_safe(cur, tmp, &sbi->s_es_lru) {
+		int shrunk;
+
 		/*
 		 * If we have already reclaimed all extents from extent
 		 * status tree, just stop the loop immediately.
@@ -964,13 +966,13 @@ retry:
 			continue;
 
 		write_lock(&ei->i_es_lock);
-		ret = __es_try_to_reclaim_extents(ei, nr_to_scan);
+		shrunk = __es_try_to_reclaim_extents(ei, nr_to_scan);
 		if (ei->i_es_lru_nr == 0)
 			list_del_init(&ei->i_es_lru);
 		write_unlock(&ei->i_es_lock);
 
-		nr_shrunk += ret;
-		nr_to_scan -= ret;
+		nr_shrunk += shrunk;
+		nr_to_scan -= shrunk;
 		if (nr_to_scan == 0)
 			break;
 	}
@@ -1007,7 +1009,20 @@ retry:
 	return nr_shrunk;
 }
 
-static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long ext4_es_count(struct shrinker *shrink,
+				   struct shrink_control *sc)
+{
+	unsigned long nr;
+	struct ext4_sb_info *sbi;
+
+	sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker);
+	nr = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
+	trace_ext4_es_shrink_enter(sbi->s_sb, sc->nr_to_scan, nr);
+	return nr;
+}
+
+static unsigned long ext4_es_scan(struct shrinker *shrink,
+				  struct shrink_control *sc)
 {
 	struct ext4_sb_info *sbi = container_of(shrink,
 					struct ext4_sb_info, s_es_shrinker);
@@ -1022,9 +1037,8 @@ static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
 
 	nr_shrunk = __ext4_es_shrink(sbi, nr_to_scan, NULL);
 
-	ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
 	trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk, ret);
-	return ret;
+	return nr_shrunk;
 }
 
 void ext4_es_register_shrinker(struct ext4_sb_info *sbi)
@@ -1032,7 +1046,8 @@ void ext4_es_register_shrinker(struct ext4_sb_info *sbi)
 	INIT_LIST_HEAD(&sbi->s_es_lru);
 	spin_lock_init(&sbi->s_es_lru_lock);
 	sbi->s_es_last_sorted = 0;
-	sbi->s_es_shrinker.shrink = ext4_es_shrink;
+	sbi->s_es_shrinker.scan_objects = ext4_es_scan;
+	sbi->s_es_shrinker.count_objects = ext4_es_count;
 	sbi->s_es_shrinker.seeks = DEFAULT_SEEKS;
 	register_shrinker(&sbi->s_es_shrinker);
 }
@@ -1076,7 +1091,7 @@ static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
 	struct ext4_es_tree *tree = &ei->i_es_tree;
 	struct rb_node *node;
 	struct extent_status *es;
-	int nr_shrunk = 0;
+	unsigned long nr_shrunk = 0;
 	static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
 				      DEFAULT_RATELIMIT_BURST);
 

fs/gfs2/glock.c

@@ -1427,21 +1427,22 @@ __acquires(&lru_lock)
  * gfs2_dispose_glock_lru() above.
  */
 
-static void gfs2_scan_glock_lru(int nr)
+static long gfs2_scan_glock_lru(int nr)
 {
 	struct gfs2_glock *gl;
 	LIST_HEAD(skipped);
 	LIST_HEAD(dispose);
+	long freed = 0;
 
 	spin_lock(&lru_lock);
-	while(nr && !list_empty(&lru_list)) {
+	while ((nr-- >= 0) && !list_empty(&lru_list)) {
 		gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru);
 
 		/* Test for being demotable */
 		if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
 			list_move(&gl->gl_lru, &dispose);
 			atomic_dec(&lru_count);
-			nr--;
+			freed++;
 			continue;
 		}
 
@@ -1451,23 +1452,28 @@ static void gfs2_scan_glock_lru(int nr)
 	if (!list_empty(&dispose))
 		gfs2_dispose_glock_lru(&dispose);
 	spin_unlock(&lru_lock);
+
+	return freed;
 }
 
-static int gfs2_shrink_glock_memory(struct shrinker *shrink,
-				    struct shrink_control *sc)
+static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink,
+					    struct shrink_control *sc)
 {
-	if (sc->nr_to_scan) {
-		if (!(sc->gfp_mask & __GFP_FS))
-			return -1;
-		gfs2_scan_glock_lru(sc->nr_to_scan);
-	}
+	if (!(sc->gfp_mask & __GFP_FS))
+		return SHRINK_STOP;
+	return gfs2_scan_glock_lru(sc->nr_to_scan);
+}
 
-	return (atomic_read(&lru_count) / 100) * sysctl_vfs_cache_pressure;
+static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink,
+					     struct shrink_control *sc)
+{
+	return vfs_pressure_ratio(atomic_read(&lru_count));
 }
 
 static struct shrinker glock_shrinker = {
-	.shrink = gfs2_shrink_glock_memory,
 	.seeks = DEFAULT_SEEKS,
+	.count_objects = gfs2_glock_shrink_count,
+	.scan_objects = gfs2_glock_shrink_scan,
 };
 
 /**

fs/gfs2/main.c

@@ -32,7 +32,8 @@
 struct workqueue_struct *gfs2_control_wq;
 
 static struct shrinker qd_shrinker = {
-	.shrink = gfs2_shrink_qd_memory,
+	.count_objects = gfs2_qd_shrink_count,
+	.scan_objects = gfs2_qd_shrink_scan,
 	.seeks = DEFAULT_SEEKS,
 };
 

fs/gfs2/quota.c

@@ -75,17 +75,16 @@ static LIST_HEAD(qd_lru_list);
 static atomic_t qd_lru_count = ATOMIC_INIT(0);
 static DEFINE_SPINLOCK(qd_lru_lock);
 
-int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
+unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
+				  struct shrink_control *sc)
 {
 	struct gfs2_quota_data *qd;
 	struct gfs2_sbd *sdp;
 	int nr_to_scan = sc->nr_to_scan;
-
-	if (nr_to_scan == 0)
-		goto out;
+	long freed = 0;
 
 	if (!(sc->gfp_mask & __GFP_FS))
-		return -1;
+		return SHRINK_STOP;
 
 	spin_lock(&qd_lru_lock);
 	while (nr_to_scan && !list_empty(&qd_lru_list)) {
@@ -110,11 +109,16 @@ int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
 		kmem_cache_free(gfs2_quotad_cachep, qd);
 		spin_lock(&qd_lru_lock);
 		nr_to_scan--;
+		freed++;
 	}
 	spin_unlock(&qd_lru_lock);
+	return freed;
+}
 
-out:
-	return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
+unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
+				   struct shrink_control *sc)
+{
+	return vfs_pressure_ratio(atomic_read(&qd_lru_count));
 }
 
 static u64 qd2index(struct gfs2_quota_data *qd)

fs/gfs2/quota.h

@@ -53,8 +53,10 @@ static inline int gfs2_quota_lock_check(struct gfs2_inode *ip)
 	return ret;
 }
 
-extern int gfs2_shrink_qd_memory(struct shrinker *shrink,
-				 struct shrink_control *sc);
+extern unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
+					  struct shrink_control *sc);
+extern unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
+					 struct shrink_control *sc);
 extern const struct quotactl_ops gfs2_quotactl_ops;
 
 #endif /* __QUOTA_DOT_H__ */

fs/inode.c

@@ -17,6 +17,7 @@
 #include <linux/prefetch.h>
 #include <linux/buffer_head.h> /* for inode_has_buffers */
 #include <linux/ratelimit.h>
+#include <linux/list_lru.h>
 #include "internal.h"
 
 /*
@@ -24,7 +25,7 @@
  *
  * inode->i_lock protects:
  *   inode->i_state, inode->i_hash, __iget()
- * inode->i_sb->s_inode_lru_lock protects:
+ * Inode LRU list locks protect:
  *   inode->i_sb->s_inode_lru, inode->i_lru
  * inode_sb_list_lock protects:
  *   sb->s_inodes, inode->i_sb_list
@@ -37,7 +38,7 @@
  *
  * inode_sb_list_lock
  *   inode->i_lock
- *     inode->i_sb->s_inode_lru_lock
+ *     Inode LRU list locks
  *
  * bdi->wb.list_lock
  *   inode->i_lock
@@ -70,33 +71,33 @@ EXPORT_SYMBOL(empty_aops);
  */
 struct inodes_stat_t inodes_stat;
 
-static DEFINE_PER_CPU(unsigned int, nr_inodes);
-static DEFINE_PER_CPU(unsigned int, nr_unused);
+static DEFINE_PER_CPU(unsigned long, nr_inodes);
+static DEFINE_PER_CPU(unsigned long, nr_unused);
 
 static struct kmem_cache *inode_cachep __read_mostly;
 
-static int get_nr_inodes(void)
+static long get_nr_inodes(void)
 {
 	int i;
-	int sum = 0;
+	long sum = 0;
 	for_each_possible_cpu(i)
 		sum += per_cpu(nr_inodes, i);
 	return sum < 0 ? 0 : sum;
 }
 
-static inline int get_nr_inodes_unused(void)
+static inline long get_nr_inodes_unused(void)
 {
 	int i;
-	int sum = 0;
+	long sum = 0;
 	for_each_possible_cpu(i)
 		sum += per_cpu(nr_unused, i);
 	return sum < 0 ? 0 : sum;
 }
 
-int get_nr_dirty_inodes(void)
+long get_nr_dirty_inodes(void)
 {
 	/* not actually dirty inodes, but a wild approximation */
-	int nr_dirty = get_nr_inodes() - get_nr_inodes_unused();
+	long nr_dirty = get_nr_inodes() - get_nr_inodes_unused();
 	return nr_dirty > 0 ? nr_dirty : 0;
 }
 
@@ -109,7 +110,7 @@ int proc_nr_inodes(ctl_table *table, int write,
 {
 	inodes_stat.nr_inodes = get_nr_inodes();
 	inodes_stat.nr_unused = get_nr_inodes_unused();
-	return proc_dointvec(table, write, buffer, lenp, ppos);
+	return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 }
 #endif
 
@@ -401,13 +402,8 @@ EXPORT_SYMBOL(ihold);
 
 static void inode_lru_list_add(struct inode *inode)
 {
-	spin_lock(&inode->i_sb->s_inode_lru_lock);
-	if (list_empty(&inode->i_lru)) {
-		list_add(&inode->i_lru, &inode->i_sb->s_inode_lru);
-		inode->i_sb->s_nr_inodes_unused++;
+	if (list_lru_add(&inode->i_sb->s_inode_lru, &inode->i_lru))
 		this_cpu_inc(nr_unused);
-	}
-	spin_unlock(&inode->i_sb->s_inode_lru_lock);
 }
 
 /*
@@ -425,13 +421,9 @@ void inode_add_lru(struct inode *inode)
 
 static void inode_lru_list_del(struct inode *inode)
 {
-	spin_lock(&inode->i_sb->s_inode_lru_lock);
-	if (!list_empty(&inode->i_lru)) {
-		list_del_init(&inode->i_lru);
-		inode->i_sb->s_nr_inodes_unused--;
+
+	if (list_lru_del(&inode->i_sb->s_inode_lru, &inode->i_lru))
 		this_cpu_dec(nr_unused);
-	}
-	spin_unlock(&inode->i_sb->s_inode_lru_lock);
 }
 
 /**
@@ -675,24 +667,8 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty)
 	return busy;
 }
 
-static int can_unuse(struct inode *inode)
-{
-	if (inode->i_state & ~I_REFERENCED)
-		return 0;
-	if (inode_has_buffers(inode))
-		return 0;
-	if (atomic_read(&inode->i_count))
-		return 0;
-	if (inode->i_data.nrpages)
-		return 0;
-	return 1;
-}
-
 /*
- * Walk the superblock inode LRU for freeable inodes and attempt to free them.
- * This is called from the superblock shrinker function with a number of inodes
- * to trim from the LRU. Inodes to be freed are moved to a temporary list and
- * then are freed outside inode_lock by dispose_list().
+ * Isolate the inode from the LRU in preparation for freeing it.
  *
  * Any inodes which are pinned purely because of attached pagecache have their
  * pagecache removed.  If the inode has metadata buffers attached to
@@ -706,89 +682,82 @@ static int can_unuse(struct inode *inode)
  * LRU does not have strict ordering. Hence we don't want to reclaim inodes
  * with this flag set because they are the inodes that are out of order.
  */
-void prune_icache_sb(struct super_block *sb, int nr_to_scan)
+static enum lru_status
+inode_lru_isolate(struct list_head *item, spinlock_t *lru_lock, void *arg)
 {
-	LIST_HEAD(freeable);
-	int nr_scanned;
-	unsigned long reap = 0;
+	struct list_head *freeable = arg;
+	struct inode	*inode = container_of(item, struct inode, i_lru);
 
-	spin_lock(&sb->s_inode_lru_lock);
-	for (nr_scanned = nr_to_scan; nr_scanned >= 0; nr_scanned--) {
-		struct inode *inode;
+	/*
+	 * we are inverting the lru lock/inode->i_lock here, so use a trylock.
+	 * If we fail to get the lock, just skip it.
+	 */
+	if (!spin_trylock(&inode->i_lock))
+		return LRU_SKIP;
 
-		if (list_empty(&sb->s_inode_lru))
-			break;
+	/*
+	 * Referenced or dirty inodes are still in use. Give them another pass
+	 * through the LRU as we canot reclaim them now.
+	 */
+	if (atomic_read(&inode->i_count) ||
+	    (inode->i_state & ~I_REFERENCED)) {
+		list_del_init(&inode->i_lru);
+		spin_unlock(&inode->i_lock);
+		this_cpu_dec(nr_unused);
+		return LRU_REMOVED;
+	}
 
-		inode = list_entry(sb->s_inode_lru.prev, struct inode, i_lru);
+	/* recently referenced inodes get one more pass */
+	if (inode->i_state & I_REFERENCED) {
+		inode->i_state &= ~I_REFERENCED;
+		spin_unlock(&inode->i_lock);
+		return LRU_ROTATE;
+	}
 
-		/*
-		 * we are inverting the sb->s_inode_lru_lock/inode->i_lock here,
-		 * so use a trylock. If we fail to get the lock, just move the
-		 * inode to the back of the list so we don't spin on it.
-		 */
-		if (!spin_trylock(&inode->i_lock)) {
-			list_move(&inode->i_lru, &sb->s_inode_lru);
-			continue;
+	if (inode_has_buffers(inode) || inode->i_data.nrpages) {
+		__iget(inode);
+		spin_unlock(&inode->i_lock);
+		spin_unlock(lru_lock);
+		if (remove_inode_buffers(inode)) {
+			unsigned long reap;
+			reap = invalidate_mapping_pages(&inode->i_data, 0, -1);
+			if (current_is_kswapd())
+				__count_vm_events(KSWAPD_INODESTEAL, reap);
+			else
+				__count_vm_events(PGINODESTEAL, reap);
+			if (current->reclaim_state)
+				current->reclaim_state->reclaimed_slab += reap;
 		}
+		iput(inode);
+		spin_lock(lru_lock);
+		return LRU_RETRY;
+	}
 
-		/*
-		 * Referenced or dirty inodes are still in use. Give them
-		 * another pass through the LRU as we canot reclaim them now.
-		 */
-		if (atomic_read(&inode->i_count) ||
-		    (inode->i_state & ~I_REFERENCED)) {
-			list_del_init(&inode->i_lru);
-			spin_unlock(&inode->i_lock);
-			sb->s_nr_inodes_unused--;
-			this_cpu_dec(nr_unused);
-			continue;
-		}
+	WARN_ON(inode->i_state & I_NEW);
+	inode->i_state |= I_FREEING;
+	list_move(&inode->i_lru, freeable);
+	spin_unlock(&inode->i_lock);
 
-		/* recently referenced inodes get one more pass */
-		if (inode->i_state & I_REFERENCED) {
-			inode->i_state &= ~I_REFERENCED;
-			list_move(&inode->i_lru, &sb->s_inode_lru);
-			spin_unlock(&inode->i_lock);
-			continue;
-		}
-		if (inode_has_buffers(inode) || inode->i_data.nrpages) {
-			__iget(inode);
-			spin_unlock(&inode->i_lock);
-			spin_unlock(&sb->s_inode_lru_lock);
-			if (remove_inode_buffers(inode))
-				reap += invalidate_mapping_pages(&inode->i_data,
-								0, -1);
-			iput(inode);
-			spin_lock(&sb->s_inode_lru_lock);
-
-			if (inode != list_entry(sb->s_inode_lru.next,
-						struct inode, i_lru))
-				continue;	/* wrong inode or list_empty */
-			/* avoid lock inversions with trylock */
-			if (!spin_trylock(&inode->i_lock))
-				continue;
-			if (!can_unuse(inode)) {
-				spin_unlock(&inode->i_lock);
-				continue;
-			}
-		}
-		WARN_ON(inode->i_state & I_NEW);
-		inode->i_state |= I_FREEING;
-		spin_unlock(&inode->i_lock);
+	this_cpu_dec(nr_unused);
+	return LRU_REMOVED;
+}
 
-		list_move(&inode->i_lru, &freeable);
-		sb->s_nr_inodes_unused--;
-		this_cpu_dec(nr_unused);
-	}
-	if (current_is_kswapd())
-		__count_vm_events(KSWAPD_INODESTEAL, reap);
-	else
-		__count_vm_events(PGINODESTEAL, reap);
-	spin_unlock(&sb->s_inode_lru_lock);
-	if (current->reclaim_state)
-		current->reclaim_state->reclaimed_slab += reap;
+/*
+ * Walk the superblock inode LRU for freeable inodes and attempt to free them.
+ * This is called from the superblock shrinker function with a number of inodes
+ * to trim from the LRU. Inodes to be freed are moved to a temporary list and
+ * then are freed outside inode_lock by dispose_list().
+ */
+long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
+		     int nid)
+{
+	LIST_HEAD(freeable);
+	long freed;
 
+	freed = list_lru_walk_node(&sb->s_inode_lru, nid, inode_lru_isolate,
+				       &freeable, &nr_to_scan);
 	dispose_list(&freeable);
+	return freed;
 }
 
 static void __wait_on_freeing_inode(struct inode *inode);

fs/internal.h

@@ -114,6 +114,8 @@ extern int open_check_o_direct(struct file *f);
  * inode.c
  */
 extern spinlock_t inode_sb_list_lock;
+extern long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
+			    int nid);
 extern void inode_add_lru(struct inode *inode);
 
 /*
@@ -121,7 +123,7 @@ extern void inode_add_lru(struct inode *inode);
  */
 extern void inode_wb_list_del(struct inode *inode);
 
-extern int get_nr_dirty_inodes(void);
+extern long get_nr_dirty_inodes(void);
 extern void evict_inodes(struct super_block *);
 extern int invalidate_inodes(struct super_block *, bool);
 
@@ -130,6 +132,8 @@ extern int invalidate_inodes(struct super_block *, bool);
  */
 extern struct dentry *__d_alloc(struct super_block *, const struct qstr *);
 extern int d_set_mounted(struct dentry *dentry);
+extern long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan,
+			    int nid);
 
 /*
  * read_write.c

fs/mbcache.c

@@ -86,18 +86,6 @@ static LIST_HEAD(mb_cache_list);
 static LIST_HEAD(mb_cache_lru_list);
 static DEFINE_SPINLOCK(mb_cache_spinlock);
 
-/*
- * What the mbcache registers as to get shrunk dynamically.
- */
-
-static int mb_cache_shrink_fn(struct shrinker *shrink,
-			      struct shrink_control *sc);
-
-static struct shrinker mb_cache_shrinker = {
-	.shrink = mb_cache_shrink_fn,
-	.seeks = DEFAULT_SEEKS,
-};
-
 static inline int
 __mb_cache_entry_is_hashed(struct mb_cache_entry *ce)
 {
@@ -151,7 +139,7 @@ forget:
 
 
 /*
- * mb_cache_shrink_fn()  memory pressure callback
+ * mb_cache_shrink_scan()  memory pressure callback
  *
  * This function is called by the kernel memory management when memory
  * gets low.
@@ -159,17 +147,16 @@ forget:
  * @shrink: (ignored)
  * @sc: shrink_control passed from reclaim
  *
- * Returns the number of objects which are present in the cache.
+ * Returns the number of objects freed.
  */
-static int
-mb_cache_shrink_fn(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long
+mb_cache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
 	LIST_HEAD(free_list);
-	struct mb_cache *cache;
 	struct mb_cache_entry *entry, *tmp;
-	int count = 0;
 	int nr_to_scan = sc->nr_to_scan;
 	gfp_t gfp_mask = sc->gfp_mask;
+	unsigned long freed = 0;
 
 	mb_debug("trying to free %d entries", nr_to_scan);
 	spin_lock(&mb_cache_spinlock);
@@ -179,19 +166,37 @@ mb_cache_shrink_fn(struct shrinker *shrink, struct shrink_control *sc)
 				   struct mb_cache_entry, e_lru_list);
 		list_move_tail(&ce->e_lru_list, &free_list);
 		__mb_cache_entry_unhash(ce);
+		freed++;
+	}
+	spin_unlock(&mb_cache_spinlock);
+	list_for_each_entry_safe(entry, tmp, &free_list, e_lru_list) {
+		__mb_cache_entry_forget(entry, gfp_mask);
 	}
+	return freed;
+}
+
+static unsigned long
+mb_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+	struct mb_cache *cache;
+	unsigned long count = 0;
+
+	spin_lock(&mb_cache_spinlock);
 	list_for_each_entry(cache, &mb_cache_list, c_cache_list) {
 		mb_debug("cache %s (%d)", cache->c_name,
 			  atomic_read(&cache->c_entry_count));
 		count += atomic_read(&cache->c_entry_count);
 	}
 	spin_unlock(&mb_cache_spinlock);
-	list_for_each_entry_safe(entry, tmp, &free_list, e_lru_list) {
-		__mb_cache_entry_forget(entry, gfp_mask);
-	}
-	return (count / 100) * sysctl_vfs_cache_pressure;
+
+	return vfs_pressure_ratio(count);
 }
 
+static struct shrinker mb_cache_shrinker = {
+	.count_objects = mb_cache_shrink_count,
+	.scan_objects = mb_cache_shrink_scan,
+	.seeks = DEFAULT_SEEKS,
+};
 
 /*
  * mb_cache_create()  create a new cache

fs/namei.c

@@ -660,29 +660,6 @@ static __always_inline void set_root_rcu(struct nameidata *nd)
 	}
 }
 
-static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link)
-{
-	int ret;
-
-	if (IS_ERR(link))
-		goto fail;
-
-	if (*link == '/') {
-		set_root(nd);
-		path_put(&nd->path);
-		nd->path = nd->root;
-		path_get(&nd->root);
-		nd->flags |= LOOKUP_JUMPED;
-	}
-	nd->inode = nd->path.dentry->d_inode;
-
-	ret = link_path_walk(link, nd);
-	return ret;
-fail:
-	path_put(&nd->path);
-	return PTR_ERR(link);
-}
-
 static void path_put_conditional(struct path *path, struct nameidata *nd)
 {
 	dput(path->dentry);
@@ -874,7 +851,20 @@ follow_link(struct path *link, struct nameidata *nd, void **p)
 	error = 0;
 	s = nd_get_link(nd);
 	if (s) {
-		error = __vfs_follow_link(nd, s);
+		if (unlikely(IS_ERR(s))) {
+			path_put(&nd->path);
+			put_link(nd, link, *p);
+			return PTR_ERR(s);
+		}
+		if (*s == '/') {
+			set_root(nd);
+			path_put(&nd->path);
+			nd->path = nd->root;
+			path_get(&nd->root);
+			nd->flags |= LOOKUP_JUMPED;
+		}
+		nd->inode = nd->path.dentry->d_inode;
+		error = link_path_walk(s, nd);
 		if (unlikely(error))
 			put_link(nd, link, *p);
 	}
@@ -2271,12 +2261,15 @@ mountpoint_last(struct nameidata *nd, struct path *path)
 		dentry = d_alloc(dir, &nd->last);
 		if (!dentry) {
 			error = -ENOMEM;
+			mutex_unlock(&dir->d_inode->i_mutex);
 			goto out;
 		}
 		dentry = lookup_real(dir->d_inode, dentry, nd->flags);
 		error = PTR_ERR(dentry);
-		if (IS_ERR(dentry))
+		if (IS_ERR(dentry)) {
+			mutex_unlock(&dir->d_inode->i_mutex);
 			goto out;
+		}
 	}
 	mutex_unlock(&dir->d_inode->i_mutex);
 
@@ -4236,11 +4229,6 @@ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 	return res;
 }
 
-int vfs_follow_link(struct nameidata *nd, const char *link)
-{
-	return __vfs_follow_link(nd, link);
-}
-
 /* get the link contents into pagecache */
 static char *page_getlink(struct dentry * dentry, struct page **ppage)
 {
@@ -4352,7 +4340,6 @@ EXPORT_SYMBOL(vfs_path_lookup);
 EXPORT_SYMBOL(inode_permission);
 EXPORT_SYMBOL(unlock_rename);
 EXPORT_SYMBOL(vfs_create);
-EXPORT_SYMBOL(vfs_follow_link);
 EXPORT_SYMBOL(vfs_link);
 EXPORT_SYMBOL(vfs_mkdir);
 EXPORT_SYMBOL(vfs_mknod);

fs/nfs/dir.c

@@ -2006,17 +2006,18 @@ static void nfs_access_free_list(struct list_head *head)
 	}
 }
 
-int nfs_access_cache_shrinker(struct shrinker *shrink,
-			      struct shrink_control *sc)
+unsigned long
+nfs_access_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
 	LIST_HEAD(head);
 	struct nfs_inode *nfsi, *next;
 	struct nfs_access_entry *cache;
 	int nr_to_scan = sc->nr_to_scan;
 	gfp_t gfp_mask = sc->gfp_mask;
+	long freed = 0;
 
 	if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
-		return (nr_to_scan == 0) ? 0 : -1;
+		return SHRINK_STOP;
 
 	spin_lock(&nfs_access_lru_lock);
 	list_for_each_entry_safe(nfsi, next, &nfs_access_lru_list, access_cache_inode_lru) {
@@ -2032,6 +2033,7 @@ int nfs_access_cache_shrinker(struct shrinker *shrink,
 				struct nfs_access_entry, lru);
 		list_move(&cache->lru, &head);
 		rb_erase(&cache->rb_node, &nfsi->access_cache);
+		freed++;
 		if (!list_empty(&nfsi->access_cache_entry_lru))
 			list_move_tail(&nfsi->access_cache_inode_lru,
 					&nfs_access_lru_list);
@@ -2046,7 +2048,13 @@ remove_lru_entry:
 	}
 	spin_unlock(&nfs_access_lru_lock);
 	nfs_access_free_list(&head);
-	return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure;
+	return freed;
+}
+
+unsigned long
+nfs_access_cache_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+	return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries));
 }
 
 static void __nfs_access_zap_cache(struct nfs_inode *nfsi, struct list_head *head)

fs/nfs/internal.h

@@ -273,8 +273,10 @@ extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
 			   const char *ip_addr);
 
 /* dir.c */
-extern int nfs_access_cache_shrinker(struct shrinker *shrink,
-					struct shrink_control *sc);
+extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
+					    struct shrink_control *sc);
+extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
+					   struct shrink_control *sc);
 struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
 int nfs_create(struct inode *, struct dentry *, umode_t, bool);
 int nfs_mkdir(struct inode *, struct dentry *, umode_t);

fs/nfs/super.c

@@ -360,7 +360,8 @@ static void unregister_nfs4_fs(void)
 #endif
 
 static struct shrinker acl_shrinker = {
-	.shrink		= nfs_access_cache_shrinker,
+	.count_objects	= nfs_access_cache_count,
+	.scan_objects	= nfs_access_cache_scan,
 	.seeks		= DEFAULT_SEEKS,
 };
 

fs/nfsd/nfscache.c

@@ -59,11 +59,14 @@ static unsigned int		longest_chain_cachesize;
 
 static int	nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec);
 static void	cache_cleaner_func(struct work_struct *unused);
-static int 	nfsd_reply_cache_shrink(struct shrinker *shrink,
-					struct shrink_control *sc);
+static unsigned long nfsd_reply_cache_count(struct shrinker *shrink,
+					    struct shrink_control *sc);
+static unsigned long nfsd_reply_cache_scan(struct shrinker *shrink,
+					   struct shrink_control *sc);
 
 static struct shrinker nfsd_reply_cache_shrinker = {
-	.shrink	= nfsd_reply_cache_shrink,
+	.scan_objects = nfsd_reply_cache_scan,
+	.count_objects = nfsd_reply_cache_count,
 	.seeks	= 1,
 };
 
@@ -232,16 +235,18 @@ nfsd_cache_entry_expired(struct svc_cacherep *rp)
  * Walk the LRU list and prune off entries that are older than RC_EXPIRE.
  * Also prune the oldest ones when the total exceeds the max number of entries.
  */
-static void
+static long
 prune_cache_entries(void)
 {
 	struct svc_cacherep *rp, *tmp;
+	long freed = 0;
 
 	list_for_each_entry_safe(rp, tmp, &lru_head, c_lru) {
 		if (!nfsd_cache_entry_expired(rp) &&
 		    num_drc_entries <= max_drc_entries)
 			break;
 		nfsd_reply_cache_free_locked(rp);
+		freed++;
 	}
 
 	/*
@@ -254,6 +259,7 @@ prune_cache_entries(void)
 		cancel_delayed_work(&cache_cleaner);
 	else
 		mod_delayed_work(system_wq, &cache_cleaner, RC_EXPIRE);
+	return freed;
 }
 
 static void
@@ -264,20 +270,28 @@ cache_cleaner_func(struct work_struct *unused)
 	spin_unlock(&cache_lock);
 }
 
-static int
-nfsd_reply_cache_shrink(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long
+nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc)
 {
-	unsigned int num;
+	unsigned long num;
 
 	spin_lock(&cache_lock);
-	if (sc->nr_to_scan)
-		prune_cache_entries();
 	num = num_drc_entries;
 	spin_unlock(&cache_lock);
 
 	return num;
 }
 
+static unsigned long
+nfsd_reply_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
+{
+	unsigned long freed;
+
+	spin_lock(&cache_lock);
+	freed = prune_cache_entries();
+	spin_unlock(&cache_lock);
+	return freed;
+}
 /*
  * Walk an xdr_buf and get a CRC for at most the first RC_CSUMLEN bytes
  */

fs/quota/dquot.c

@@ -687,45 +687,37 @@ int dquot_quota_sync(struct super_block *sb, int type)
 }
 EXPORT_SYMBOL(dquot_quota_sync);
 
-/* Free unused dquots from cache */
-static void prune_dqcache(int count)
+static unsigned long
+dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
 	struct list_head *head;
 	struct dquot *dquot;
+	unsigned long freed = 0;
 
 	head = free_dquots.prev;
-	while (head != &free_dquots && count) {
+	while (head != &free_dquots && sc->nr_to_scan) {
 		dquot = list_entry(head, struct dquot, dq_free);
 		remove_dquot_hash(dquot);
 		remove_free_dquot(dquot);
 		remove_inuse(dquot);
 		do_destroy_dquot(dquot);
-		count--;
+		sc->nr_to_scan--;
+		freed++;
 		head = free_dquots.prev;
 	}
+	return freed;
 }
 
-/*
- * This is called from kswapd when we think we need some
- * more memory
- */
-static int shrink_dqcache_memory(struct shrinker *shrink,
-				 struct shrink_control *sc)
+static unsigned long
+dqcache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
 {
-	int nr = sc->nr_to_scan;
-
-	if (nr) {
-		spin_lock(&dq_list_lock);
-		prune_dqcache(nr);
-		spin_unlock(&dq_list_lock);
-	}
-	return ((unsigned)
-		percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS])
-		/100) * sysctl_vfs_cache_pressure;
+	return vfs_pressure_ratio(
+	percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS]));
 }
 
 static struct shrinker dqcache_shrinker = {
-	.shrink = shrink_dqcache_memory,
+	.count_objects = dqcache_shrink_count,
+	.scan_objects = dqcache_shrink_scan,
 	.seeks = DEFAULT_SEEKS,
 };
 

fs/super.c

@@ -53,11 +53,15 @@ static char *sb_writers_name[SB_FREEZE_LEVELS] = {
  * shrinker path and that leads to deadlock on the shrinker_rwsem. Hence we
  * take a passive reference to the superblock to avoid this from occurring.
  */
-static int prune_super(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long super_cache_scan(struct shrinker *shrink,
+				      struct shrink_control *sc)
 {
 	struct super_block *sb;
-	int	fs_objects = 0;
-	int	total_objects;
+	long	fs_objects = 0;
+	long	total_objects;
+	long	freed = 0;
+	long	dentries;
+	long	inodes;
 
 	sb = container_of(shrink, struct super_block, s_shrink);
 
@@ -65,46 +69,62 @@ static int prune_super(struct shrinker *shrink, struct shrink_control *sc)
 	 * Deadlock avoidance.  We may hold various FS locks, and we don't want
 	 * to recurse into the FS that called us in clear_inode() and friends..
 	 */
-	if (sc->nr_to_scan && !(sc->gfp_mask & __GFP_FS))
-		return -1;
+	if (!(sc->gfp_mask & __GFP_FS))
+		return SHRINK_STOP;
 
 	if (!grab_super_passive(sb))
-		return -1;
+		return SHRINK_STOP;
 
 	if (sb->s_op->nr_cached_objects)
-		fs_objects = sb->s_op->nr_cached_objects(sb);
-
-	total_objects = sb->s_nr_dentry_unused +
-			sb->s_nr_inodes_unused + fs_objects + 1;
-
-	if (sc->nr_to_scan) {
-		int	dentries;
-		int	inodes;
-
-		/* proportion the scan between the caches */
-		dentries = (sc->nr_to_scan * sb->s_nr_dentry_unused) /
-							total_objects;
-		inodes = (sc->nr_to_scan * sb->s_nr_inodes_unused) /
-							total_objects;
-		if (fs_objects)
-			fs_objects = (sc->nr_to_scan * fs_objects) /
-							total_objects;
-		/*
-		 * prune the dcache first as the icache is pinned by it, then
-		 * prune the icache, followed by the filesystem specific caches
-		 */
-		prune_dcache_sb(sb, dentries);
-		prune_icache_sb(sb, inodes);
+		fs_objects = sb->s_op->nr_cached_objects(sb, sc->nid);
 
-		if (fs_objects && sb->s_op->free_cached_objects) {
-			sb->s_op->free_cached_objects(sb, fs_objects);
-			fs_objects = sb->s_op->nr_cached_objects(sb);
-		}
-		total_objects = sb->s_nr_dentry_unused +
-				sb->s_nr_inodes_unused + fs_objects;
+	inodes = list_lru_count_node(&sb->s_inode_lru, sc->nid);
+	dentries = list_lru_count_node(&sb->s_dentry_lru, sc->nid);
+	total_objects = dentries + inodes + fs_objects + 1;
+
+	/* proportion the scan between the caches */
+	dentries = mult_frac(sc->nr_to_scan, dentries, total_objects);
+	inodes = mult_frac(sc->nr_to_scan, inodes, total_objects);
+
+	/*
+	 * prune the dcache first as the icache is pinned by it, then
+	 * prune the icache, followed by the filesystem specific caches
+	 */
+	freed = prune_dcache_sb(sb, dentries, sc->nid);
+	freed += prune_icache_sb(sb, inodes, sc->nid);
+
+	if (fs_objects) {
+		fs_objects = mult_frac(sc->nr_to_scan, fs_objects,
+								total_objects);
+		freed += sb->s_op->free_cached_objects(sb, fs_objects,
+						       sc->nid);
 	}
 
-	total_objects = (total_objects / 100) * sysctl_vfs_cache_pressure;
+	drop_super(sb);
+	return freed;
+}
+
+static unsigned long super_cache_count(struct shrinker *shrink,
+				       struct shrink_control *sc)
+{
+	struct super_block *sb;
+	long	total_objects = 0;
+
+	sb = container_of(shrink, struct super_block, s_shrink);
+
+	if (!grab_super_passive(sb))
+		return 0;
+
+	if (sb->s_op && sb->s_op->nr_cached_objects)
+		total_objects = sb->s_op->nr_cached_objects(sb,
+						 sc->nid);
+
+	total_objects += list_lru_count_node(&sb->s_dentry_lru,
+						 sc->nid);
+	total_objects += list_lru_count_node(&sb->s_inode_lru,
+						 sc->nid);
+
+	total_objects = vfs_pressure_ratio(total_objects);
 	drop_super(sb);
 	return total_objects;
 }
@@ -175,9 +195,12 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
 		INIT_HLIST_NODE(&s->s_instances);
 		INIT_HLIST_BL_HEAD(&s->s_anon);
 		INIT_LIST_HEAD(&s->s_inodes);
-		INIT_LIST_HEAD(&s->s_dentry_lru);
-		INIT_LIST_HEAD(&s->s_inode_lru);
-		spin_lock_init(&s->s_inode_lru_lock);
+
+		if (list_lru_init(&s->s_dentry_lru))
+			goto err_out;
+		if (list_lru_init(&s->s_inode_lru))
+			goto err_out_dentry_lru;
+
 		INIT_LIST_HEAD(&s->s_mounts);
 		init_rwsem(&s->s_umount);
 		lockdep_set_class(&s->s_umount, &type->s_umount_key);
@@ -210,11 +233,16 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
 		s->cleancache_poolid = -1;
 
 		s->s_shrink.seeks = DEFAULT_SEEKS;
-		s->s_shrink.shrink = prune_super;
+		s->s_shrink.scan_objects = super_cache_scan;
+		s->s_shrink.count_objects = super_cache_count;
 		s->s_shrink.batch = 1024;
+		s->s_shrink.flags = SHRINKER_NUMA_AWARE;
 	}
 out:
 	return s;
+
+err_out_dentry_lru:
+	list_lru_destroy(&s->s_dentry_lru);
 err_out:
 	security_sb_free(s);
 #ifdef CONFIG_SMP
@@ -295,6 +323,9 @@ void deactivate_locked_super(struct super_block *s)
 
 		/* caches are now gone, we can safely kill the shrinker now */
 		unregister_shrinker(&s->s_shrink);
+		list_lru_destroy(&s->s_dentry_lru);
+		list_lru_destroy(&s->s_inode_lru);
+
 		put_filesystem(fs);
 		put_super(s);
 	} else {

fs/ubifs/shrinker.c

@@ -277,18 +277,25 @@ static int kick_a_thread(void)
 	return 0;
 }
 
-int ubifs_shrinker(struct shrinker *shrink, struct shrink_control *sc)
+unsigned long ubifs_shrink_count(struct shrinker *shrink,
+				 struct shrink_control *sc)
 {
-	int nr = sc->nr_to_scan;
-	int freed, contention = 0;
 	long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt);
 
-	if (nr == 0)
-		/*
-		 * Due to the way UBIFS updates the clean znode counter it may
-		 * temporarily be negative.
-		 */
-		return clean_zn_cnt >= 0 ? clean_zn_cnt : 1;
+	/*
+	 * Due to the way UBIFS updates the clean znode counter it may
+	 * temporarily be negative.
+	 */
+	return clean_zn_cnt >= 0 ? clean_zn_cnt : 1;
+}
+
+unsigned long ubifs_shrink_scan(struct shrinker *shrink,
+				struct shrink_control *sc)
+{
+	unsigned long nr = sc->nr_to_scan;
+	int contention = 0;
+	unsigned long freed;
+	long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt);
 
 	if (!clean_zn_cnt) {
 		/*
@@ -316,10 +323,10 @@ int ubifs_shrinker(struct shrinker *shrink, struct shrink_control *sc)
 
 	if (!freed && contention) {
 		dbg_tnc("freed nothing, but contention");
-		return -1;
+		return SHRINK_STOP;
 	}
 
 out:
-	dbg_tnc("%d znodes were freed, requested %d", freed, nr);
+	dbg_tnc("%lu znodes were freed, requested %lu", freed, nr);
 	return freed;
 }

fs/ubifs/super.c

@@ -49,7 +49,8 @@ struct kmem_cache *ubifs_inode_slab;
 
 /* UBIFS TNC shrinker description */
 static struct shrinker ubifs_shrinker_info = {
-	.shrink = ubifs_shrinker,
+	.scan_objects = ubifs_shrink_scan,
+	.count_objects = ubifs_shrink_count,
 	.seeks = DEFAULT_SEEKS,
 };
 

fs/ubifs/ubifs.h

@@ -1624,7 +1624,10 @@ int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot);
 int ubifs_tnc_end_commit(struct ubifs_info *c);
 
 /* shrinker.c */
-int ubifs_shrinker(struct shrinker *shrink, struct shrink_control *sc);
+unsigned long ubifs_shrink_scan(struct shrinker *shrink,
+				struct shrink_control *sc);
+unsigned long ubifs_shrink_count(struct shrinker *shrink,
+				 struct shrink_control *sc);
 
 /* commit.c */
 int ubifs_bg_thread(void *info);

fs/xfs/xfs_buf.c

@@ -80,54 +80,6 @@ xfs_buf_vmap_len(
 	return (bp->b_page_count * PAGE_SIZE) - bp->b_offset;
 }
 
-/*
- * xfs_buf_lru_add - add a buffer to the LRU.
- *
- * The LRU takes a new reference to the buffer so that it will only be freed
- * once the shrinker takes the buffer off the LRU.
- */
-STATIC void
-xfs_buf_lru_add(
-	struct xfs_buf	*bp)
-{
-	struct xfs_buftarg *btp = bp->b_target;
-
-	spin_lock(&btp->bt_lru_lock);
-	if (list_empty(&bp->b_lru)) {
-		atomic_inc(&bp->b_hold);
-		list_add_tail(&bp->b_lru, &btp->bt_lru);
-		btp->bt_lru_nr++;
-		bp->b_lru_flags &= ~_XBF_LRU_DISPOSE;
-	}
-	spin_unlock(&btp->bt_lru_lock);
-}
-
-/*
- * xfs_buf_lru_del - remove a buffer from the LRU
- *
- * The unlocked check is safe here because it only occurs when there are not
- * b_lru_ref counts left on the inode under the pag->pag_buf_lock. it is there
- * to optimise the shrinker removing the buffer from the LRU and calling
- * xfs_buf_free(). i.e. it removes an unnecessary round trip on the
- * bt_lru_lock.
- */
-STATIC void
-xfs_buf_lru_del(
-	struct xfs_buf	*bp)
-{
-	struct xfs_buftarg *btp = bp->b_target;
-
-	if (list_empty(&bp->b_lru))
-		return;
-
-	spin_lock(&btp->bt_lru_lock);
-	if (!list_empty(&bp->b_lru)) {
-		list_del_init(&bp->b_lru);
-		btp->bt_lru_nr--;
-	}
-	spin_unlock(&btp->bt_lru_lock);
-}
-
 /*
  * When we mark a buffer stale, we remove the buffer from the LRU and clear the
  * b_lru_ref count so that the buffer is freed immediately when the buffer
@@ -151,20 +103,14 @@ xfs_buf_stale(
 	 */
 	bp->b_flags &= ~_XBF_DELWRI_Q;
 
-	atomic_set(&(bp)->b_lru_ref, 0);
-	if (!list_empty(&bp->b_lru)) {
-		struct xfs_buftarg *btp = bp->b_target;
+	spin_lock(&bp->b_lock);
+	atomic_set(&bp->b_lru_ref, 0);
+	if (!(bp->b_state & XFS_BSTATE_DISPOSE) &&
+	    (list_lru_del(&bp->b_target->bt_lru, &bp->b_lru)))
+		atomic_dec(&bp->b_hold);
 
-		spin_lock(&btp->bt_lru_lock);
-		if (!list_empty(&bp->b_lru) &&
-		    !(bp->b_lru_flags & _XBF_LRU_DISPOSE)) {
-			list_del_init(&bp->b_lru);
-			btp->bt_lru_nr--;
-			atomic_dec(&bp->b_hold);
-		}
-		spin_unlock(&btp->bt_lru_lock);
-	}
 	ASSERT(atomic_read(&bp->b_hold) >= 1);
+	spin_unlock(&bp->b_lock);
 }
 
 static int
@@ -228,6 +174,7 @@ _xfs_buf_alloc(
 	INIT_LIST_HEAD(&bp->b_list);
 	RB_CLEAR_NODE(&bp->b_rbnode);
 	sema_init(&bp->b_sema, 0); /* held, no waiters */
+	spin_lock_init(&bp->b_lock);
 	XB_SET_OWNER(bp);
 	bp->b_target = target;
 	bp->b_flags = flags;
@@ -917,12 +864,33 @@ xfs_buf_rele(
 
 	ASSERT(atomic_read(&bp->b_hold) > 0);
 	if (atomic_dec_and_lock(&bp->b_hold, &pag->pag_buf_lock)) {
-		if (!(bp->b_flags & XBF_STALE) &&
-			   atomic_read(&bp->b_lru_ref)) {
-			xfs_buf_lru_add(bp);
+		spin_lock(&bp->b_lock);
+		if (!(bp->b_flags & XBF_STALE) && atomic_read(&bp->b_lru_ref)) {
+			/*
+			 * If the buffer is added to the LRU take a new
+			 * reference to the buffer for the LRU and clear the
+			 * (now stale) dispose list state flag
+			 */
+			if (list_lru_add(&bp->b_target->bt_lru, &bp->b_lru)) {
+				bp->b_state &= ~XFS_BSTATE_DISPOSE;
+				atomic_inc(&bp->b_hold);
+			}
+			spin_unlock(&bp->b_lock);
 			spin_unlock(&pag->pag_buf_lock);
 		} else {
-			xfs_buf_lru_del(bp);
+			/*
+			 * most of the time buffers will already be removed from
+			 * the LRU, so optimise that case by checking for the
+			 * XFS_BSTATE_DISPOSE flag indicating the last list the
+			 * buffer was on was the disposal list
+			 */
+			if (!(bp->b_state & XFS_BSTATE_DISPOSE)) {
+				list_lru_del(&bp->b_target->bt_lru, &bp->b_lru);
+			} else {
+				ASSERT(list_empty(&bp->b_lru));
+			}
+			spin_unlock(&bp->b_lock);
+
 			ASSERT(!(bp->b_flags & _XBF_DELWRI_Q));
 			rb_erase(&bp->b_rbnode, &pag->pag_buf_tree);
 			spin_unlock(&pag->pag_buf_lock);
@@ -1502,83 +1470,121 @@ xfs_buf_iomove(
  * returned. These buffers will have an elevated hold count, so wait on those
  * while freeing all the buffers only held by the LRU.
  */
+static enum lru_status
+xfs_buftarg_wait_rele(
+	struct list_head	*item,
+	spinlock_t		*lru_lock,
+	void			*arg)
+
+{
+	struct xfs_buf		*bp = container_of(item, struct xfs_buf, b_lru);
+	struct list_head	*dispose = arg;
+
+	if (atomic_read(&bp->b_hold) > 1) {
+		/* need to wait, so skip it this pass */
+		trace_xfs_buf_wait_buftarg(bp, _RET_IP_);
+		return LRU_SKIP;
+	}
+	if (!spin_trylock(&bp->b_lock))
+		return LRU_SKIP;
+
+	/*
+	 * clear the LRU reference count so the buffer doesn't get
+	 * ignored in xfs_buf_rele().
+	 */
+	atomic_set(&bp->b_lru_ref, 0);
+	bp->b_state |= XFS_BSTATE_DISPOSE;
+	list_move(item, dispose);
+	spin_unlock(&bp->b_lock);
+	return LRU_REMOVED;
+}
+
 void
 xfs_wait_buftarg(
 	struct xfs_buftarg	*btp)
 {
-	struct xfs_buf		*bp;
+	LIST_HEAD(dispose);
+	int loop = 0;
 
-restart:
-	spin_lock(&btp->bt_lru_lock);
-	while (!list_empty(&btp->bt_lru)) {
-		bp = list_first_entry(&btp->bt_lru, struct xfs_buf, b_lru);
-		if (atomic_read(&bp->b_hold) > 1) {
-			trace_xfs_buf_wait_buftarg(bp, _RET_IP_);
-			list_move_tail(&bp->b_lru, &btp->bt_lru);
-			spin_unlock(&btp->bt_lru_lock);
-			delay(100);
-			goto restart;
+	/* loop until there is nothing left on the lru list. */
+	while (list_lru_count(&btp->bt_lru)) {
+		list_lru_walk(&btp->bt_lru, xfs_buftarg_wait_rele,
+			      &dispose, LONG_MAX);
+
+		while (!list_empty(&dispose)) {
+			struct xfs_buf *bp;
+			bp = list_first_entry(&dispose, struct xfs_buf, b_lru);
+			list_del_init(&bp->b_lru);
+			xfs_buf_rele(bp);
 		}
-		/*
-		 * clear the LRU reference count so the buffer doesn't get
-		 * ignored in xfs_buf_rele().
-		 */
-		atomic_set(&bp->b_lru_ref, 0);
-		spin_unlock(&btp->bt_lru_lock);
-		xfs_buf_rele(bp);
-		spin_lock(&btp->bt_lru_lock);
+		if (loop++ != 0)
+			delay(100);
 	}
-	spin_unlock(&btp->bt_lru_lock);
 }
 
-int
-xfs_buftarg_shrink(
+static enum lru_status
+xfs_buftarg_isolate(
+	struct list_head	*item,
+	spinlock_t		*lru_lock,
+	void			*arg)
+{
+	struct xfs_buf		*bp = container_of(item, struct xfs_buf, b_lru);
+	struct list_head	*dispose = arg;
+
+	/*
+	 * we are inverting the lru lock/bp->b_lock here, so use a trylock.
+	 * If we fail to get the lock, just skip it.
+	 */
+	if (!spin_trylock(&bp->b_lock))
+		return LRU_SKIP;
+	/*
+	 * Decrement the b_lru_ref count unless the value is already
+	 * zero. If the value is already zero, we need to reclaim the
+	 * buffer, otherwise it gets another trip through the LRU.
+	 */
+	if (!atomic_add_unless(&bp->b_lru_ref, -1, 0)) {
+		spin_unlock(&bp->b_lock);
+		return LRU_ROTATE;
+	}
+
+	bp->b_state |= XFS_BSTATE_DISPOSE;
+	list_move(item, dispose);
+	spin_unlock(&bp->b_lock);
+	return LRU_REMOVED;
+}
+
+static unsigned long
+xfs_buftarg_shrink_scan(
 	struct shrinker		*shrink,
 	struct shrink_control	*sc)
 {
 	struct xfs_buftarg	*btp = container_of(shrink,
 					struct xfs_buftarg, bt_shrinker);
-	struct xfs_buf		*bp;
-	int nr_to_scan = sc->nr_to_scan;
 	LIST_HEAD(dispose);
+	unsigned long		freed;
+	unsigned long		nr_to_scan = sc->nr_to_scan;
 
-	if (!nr_to_scan)
-		return btp->bt_lru_nr;
-
-	spin_lock(&btp->bt_lru_lock);
-	while (!list_empty(&btp->bt_lru)) {
-		if (nr_to_scan-- <= 0)
-			break;
-
-		bp = list_first_entry(&btp->bt_lru, struct xfs_buf, b_lru);
-
-		/*
-		 * Decrement the b_lru_ref count unless the value is already
-		 * zero. If the value is already zero, we need to reclaim the
-		 * buffer, otherwise it gets another trip through the LRU.
-		 */
-		if (!atomic_add_unless(&bp->b_lru_ref, -1, 0)) {
-			list_move_tail(&bp->b_lru, &btp->bt_lru);
-			continue;
-		}
-
-		/*
-		 * remove the buffer from the LRU now to avoid needing another
-		 * lock round trip inside xfs_buf_rele().
-		 */
-		list_move(&bp->b_lru, &dispose);
-		btp->bt_lru_nr--;
-		bp->b_lru_flags |= _XBF_LRU_DISPOSE;
-	}
-	spin_unlock(&btp->bt_lru_lock);
+	freed = list_lru_walk_node(&btp->bt_lru, sc->nid, xfs_buftarg_isolate,
+				       &dispose, &nr_to_scan);
 
 	while (!list_empty(&dispose)) {
+		struct xfs_buf *bp;
 		bp = list_first_entry(&dispose, struct xfs_buf, b_lru);
 		list_del_init(&bp->b_lru);
 		xfs_buf_rele(bp);
 	}
 
-	return btp->bt_lru_nr;
+	return freed;
+}
+
+static unsigned long
+xfs_buftarg_shrink_count(
+	struct shrinker		*shrink,
+	struct shrink_control	*sc)
+{
+	struct xfs_buftarg	*btp = container_of(shrink,
+					struct xfs_buftarg, bt_shrinker);
+	return list_lru_count_node(&btp->bt_lru, sc->nid);
 }
 
 void
@@ -1587,6 +1593,7 @@ xfs_free_buftarg(
 	struct xfs_buftarg	*btp)
 {
 	unregister_shrinker(&btp->bt_shrinker);
+	list_lru_destroy(&btp->bt_lru);
 
 	if (mp->m_flags & XFS_MOUNT_BARRIER)
 		xfs_blkdev_issue_flush(btp);
@@ -1660,12 +1667,16 @@ xfs_alloc_buftarg(
 	if (!btp->bt_bdi)
 		goto error;
 
-	INIT_LIST_HEAD(&btp->bt_lru);
-	spin_lock_init(&btp->bt_lru_lock);
 	if (xfs_setsize_buftarg_early(btp, bdev))
 		goto error;
-	btp->bt_shrinker.shrink = xfs_buftarg_shrink;
+
+	if (list_lru_init(&btp->bt_lru))
+		goto error;
+
+	btp->bt_shrinker.count_objects = xfs_buftarg_shrink_count;
+	btp->bt_shrinker.scan_objects = xfs_buftarg_shrink_scan;
 	btp->bt_shrinker.seeks = DEFAULT_SEEKS;
+	btp->bt_shrinker.flags = SHRINKER_NUMA_AWARE;
 	register_shrinker(&btp->bt_shrinker);
 	return btp;
 

fs/xfs/xfs_buf.h

@@ -25,6 +25,7 @@
 #include <linux/fs.h>
 #include <linux/buffer_head.h>
 #include <linux/uio.h>
+#include <linux/list_lru.h>
 
 /*
  *	Base types
@@ -59,7 +60,6 @@ typedef enum {
 #define _XBF_KMEM	 (1 << 21)/* backed by heap memory */
 #define _XBF_DELWRI_Q	 (1 << 22)/* buffer on a delwri queue */
 #define _XBF_COMPOUND	 (1 << 23)/* compound buffer */
-#define _XBF_LRU_DISPOSE (1 << 24)/* buffer being discarded */
 
 typedef unsigned int xfs_buf_flags_t;
 
@@ -78,8 +78,12 @@ typedef unsigned int xfs_buf_flags_t;
 	{ _XBF_PAGES,		"PAGES" }, \
 	{ _XBF_KMEM,		"KMEM" }, \
 	{ _XBF_DELWRI_Q,	"DELWRI_Q" }, \
-	{ _XBF_COMPOUND,	"COMPOUND" }, \
-	{ _XBF_LRU_DISPOSE,	"LRU_DISPOSE" }
+	{ _XBF_COMPOUND,	"COMPOUND" }
+
+/*
+ * Internal state flags.
+ */
+#define XFS_BSTATE_DISPOSE	 (1 << 0)	/* buffer being discarded */
 
 typedef struct xfs_buftarg {
 	dev_t			bt_dev;
@@ -92,9 +96,7 @@ typedef struct xfs_buftarg {
 
 	/* LRU control structures */
 	struct shrinker		bt_shrinker;
-	struct list_head	bt_lru;
-	spinlock_t		bt_lru_lock;
-	unsigned int		bt_lru_nr;
+	struct list_lru		bt_lru;
 } xfs_buftarg_t;
 
 struct xfs_buf;
@@ -137,7 +139,8 @@ typedef struct xfs_buf {
 	 * bt_lru_lock and not by b_sema
 	 */
 	struct list_head	b_lru;		/* lru list */
-	xfs_buf_flags_t		b_lru_flags;	/* internal lru status flags */
+	spinlock_t		b_lock;		/* internal state lock */
+	unsigned int		b_state;	/* internal state flags */
 	wait_queue_head_t	b_waiters;	/* unpin waiters */
 	struct list_head	b_list;
 	struct xfs_perag	*b_pag;		/* contains rbtree root */

fs/xfs/xfs_dquot.c

@@ -940,13 +940,8 @@ xfs_qm_dqput_final(
 
 	trace_xfs_dqput_free(dqp);
 
-	mutex_lock(&qi->qi_lru_lock);
-	if (list_empty(&dqp->q_lru)) {
-		list_add_tail(&dqp->q_lru, &qi->qi_lru_list);
-		qi->qi_lru_count++;
+	if (list_lru_add(&qi->qi_lru, &dqp->q_lru))
 		XFS_STATS_INC(xs_qm_dquot_unused);
-	}
-	mutex_unlock(&qi->qi_lru_lock);
 
 	/*
 	 * If we just added a udquot to the freelist, then we want to release

fs/xfs/xfs_icache.c

@@ -1167,7 +1167,7 @@ xfs_reclaim_inodes(
  * them to be cleaned, which we hope will not be very long due to the
  * background walker having already kicked the IO off on those dirty inodes.
  */
-void
+long
 xfs_reclaim_inodes_nr(
 	struct xfs_mount	*mp,
 	int			nr_to_scan)
@@ -1176,7 +1176,7 @@ xfs_reclaim_inodes_nr(
 	xfs_reclaim_work_queue(mp);
 	xfs_ail_push_all(mp->m_ail);
 
-	xfs_reclaim_inodes_ag(mp, SYNC_TRYLOCK | SYNC_WAIT, &nr_to_scan);
+	return xfs_reclaim_inodes_ag(mp, SYNC_TRYLOCK | SYNC_WAIT, &nr_to_scan);
 }
 
 /*

fs/xfs/xfs_icache.h

@@ -46,7 +46,7 @@ void xfs_reclaim_worker(struct work_struct *work);
 
 int xfs_reclaim_inodes(struct xfs_mount *mp, int mode);
 int xfs_reclaim_inodes_count(struct xfs_mount *mp);
-void xfs_reclaim_inodes_nr(struct xfs_mount *mp, int nr_to_scan);
+long xfs_reclaim_inodes_nr(struct xfs_mount *mp, int nr_to_scan);
 
 void xfs_inode_set_reclaim_tag(struct xfs_inode *ip);
 

fs/xfs/xfs_qm.c

@@ -51,8 +51,9 @@
  */
 STATIC int	xfs_qm_init_quotainos(xfs_mount_t *);
 STATIC int	xfs_qm_init_quotainfo(xfs_mount_t *);
-STATIC int	xfs_qm_shake(struct shrinker *, struct shrink_control *);
 
+
+STATIC void	xfs_qm_dqfree_one(struct xfs_dquot *dqp);
 /*
  * We use the batch lookup interface to iterate over the dquots as it
  * currently is the only interface into the radix tree code that allows
@@ -203,12 +204,9 @@ xfs_qm_dqpurge(
 	 * We move dquots to the freelist as soon as their reference count
 	 * hits zero, so it really should be on the freelist here.
 	 */
-	mutex_lock(&qi->qi_lru_lock);
 	ASSERT(!list_empty(&dqp->q_lru));
-	list_del_init(&dqp->q_lru);
-	qi->qi_lru_count--;
+	list_lru_del(&qi->qi_lru, &dqp->q_lru);
 	XFS_STATS_DEC(xs_qm_dquot_unused);
-	mutex_unlock(&qi->qi_lru_lock);
 
 	xfs_qm_dqdestroy(dqp);
 
@@ -680,6 +678,143 @@ xfs_qm_calc_dquots_per_chunk(
 	return ndquots;
 }
 
+struct xfs_qm_isolate {
+	struct list_head	buffers;
+	struct list_head	dispose;
+};
+
+static enum lru_status
+xfs_qm_dquot_isolate(
+	struct list_head	*item,
+	spinlock_t		*lru_lock,
+	void			*arg)
+{
+	struct xfs_dquot	*dqp = container_of(item,
+						struct xfs_dquot, q_lru);
+	struct xfs_qm_isolate	*isol = arg;
+
+	if (!xfs_dqlock_nowait(dqp))
+		goto out_miss_busy;
+
+	/*
+	 * This dquot has acquired a reference in the meantime remove it from
+	 * the freelist and try again.
+	 */
+	if (dqp->q_nrefs) {
+		xfs_dqunlock(dqp);
+		XFS_STATS_INC(xs_qm_dqwants);
+
+		trace_xfs_dqreclaim_want(dqp);
+		list_del_init(&dqp->q_lru);
+		XFS_STATS_DEC(xs_qm_dquot_unused);
+		return LRU_REMOVED;
+	}
+
+	/*
+	 * If the dquot is dirty, flush it. If it's already being flushed, just
+	 * skip it so there is time for the IO to complete before we try to
+	 * reclaim it again on the next LRU pass.
+	 */
+	if (!xfs_dqflock_nowait(dqp)) {
+		xfs_dqunlock(dqp);
+		goto out_miss_busy;
+	}
+
+	if (XFS_DQ_IS_DIRTY(dqp)) {
+		struct xfs_buf	*bp = NULL;
+		int		error;
+
+		trace_xfs_dqreclaim_dirty(dqp);
+
+		/* we have to drop the LRU lock to flush the dquot */
+		spin_unlock(lru_lock);
+
+		error = xfs_qm_dqflush(dqp, &bp);
+		if (error) {
+			xfs_warn(dqp->q_mount, "%s: dquot %p flush failed",
+				 __func__, dqp);
+			goto out_unlock_dirty;
+		}
+
+		xfs_buf_delwri_queue(bp, &isol->buffers);
+		xfs_buf_relse(bp);
+		goto out_unlock_dirty;
+	}
+	xfs_dqfunlock(dqp);
+
+	/*
+	 * Prevent lookups now that we are past the point of no return.
+	 */
+	dqp->dq_flags |= XFS_DQ_FREEING;
+	xfs_dqunlock(dqp);
+
+	ASSERT(dqp->q_nrefs == 0);
+	list_move_tail(&dqp->q_lru, &isol->dispose);
+	XFS_STATS_DEC(xs_qm_dquot_unused);
+	trace_xfs_dqreclaim_done(dqp);
+	XFS_STATS_INC(xs_qm_dqreclaims);
+	return LRU_REMOVED;
+
+out_miss_busy:
+	trace_xfs_dqreclaim_busy(dqp);
+	XFS_STATS_INC(xs_qm_dqreclaim_misses);
+	return LRU_SKIP;
+
+out_unlock_dirty:
+	trace_xfs_dqreclaim_busy(dqp);
+	XFS_STATS_INC(xs_qm_dqreclaim_misses);
+	xfs_dqunlock(dqp);
+	spin_lock(lru_lock);
+	return LRU_RETRY;
+}
+
+static unsigned long
+xfs_qm_shrink_scan(
+	struct shrinker		*shrink,
+	struct shrink_control	*sc)
+{
+	struct xfs_quotainfo	*qi = container_of(shrink,
+					struct xfs_quotainfo, qi_shrinker);
+	struct xfs_qm_isolate	isol;
+	unsigned long		freed;
+	int			error;
+	unsigned long		nr_to_scan = sc->nr_to_scan;
+
+	if ((sc->gfp_mask & (__GFP_FS|__GFP_WAIT)) != (__GFP_FS|__GFP_WAIT))
+		return 0;
+
+	INIT_LIST_HEAD(&isol.buffers);
+	INIT_LIST_HEAD(&isol.dispose);
+
+	freed = list_lru_walk_node(&qi->qi_lru, sc->nid, xfs_qm_dquot_isolate, &isol,
+					&nr_to_scan);
+
+	error = xfs_buf_delwri_submit(&isol.buffers);
+	if (error)
+		xfs_warn(NULL, "%s: dquot reclaim failed", __func__);
+
+	while (!list_empty(&isol.dispose)) {
+		struct xfs_dquot	*dqp;
+
+		dqp = list_first_entry(&isol.dispose, struct xfs_dquot, q_lru);
+		list_del_init(&dqp->q_lru);
+		xfs_qm_dqfree_one(dqp);
+	}
+
+	return freed;
+}
+
+static unsigned long
+xfs_qm_shrink_count(
+	struct shrinker		*shrink,
+	struct shrink_control	*sc)
+{
+	struct xfs_quotainfo	*qi = container_of(shrink,
+					struct xfs_quotainfo, qi_shrinker);
+
+	return list_lru_count_node(&qi->qi_lru, sc->nid);
+}
+
 /*
  * This initializes all the quota information that's kept in the
  * mount structure
@@ -696,11 +831,18 @@ xfs_qm_init_quotainfo(
 
 	qinf = mp->m_quotainfo = kmem_zalloc(sizeof(xfs_quotainfo_t), KM_SLEEP);
 
+	if ((error = list_lru_init(&qinf->qi_lru))) {
+		kmem_free(qinf);
+		mp->m_quotainfo = NULL;
+		return error;
+	}
+
 	/*
 	 * See if quotainodes are setup, and if not, allocate them,
 	 * and change the superblock accordingly.
 	 */
 	if ((error = xfs_qm_init_quotainos(mp))) {
+		list_lru_destroy(&qinf->qi_lru);
 		kmem_free(qinf);
 		mp->m_quotainfo = NULL;
 		return error;
@@ -711,10 +853,6 @@ xfs_qm_init_quotainfo(
 	INIT_RADIX_TREE(&qinf->qi_pquota_tree, GFP_NOFS);
 	mutex_init(&qinf->qi_tree_lock);
 
-	INIT_LIST_HEAD(&qinf->qi_lru_list);
-	qinf->qi_lru_count = 0;
-	mutex_init(&qinf->qi_lru_lock);
-
 	/* mutex used to serialize quotaoffs */
 	mutex_init(&qinf->qi_quotaofflock);
 
@@ -779,8 +917,10 @@ xfs_qm_init_quotainfo(
 		qinf->qi_rtbwarnlimit = XFS_QM_RTBWARNLIMIT;
 	}
 
-	qinf->qi_shrinker.shrink = xfs_qm_shake;
+	qinf->qi_shrinker.count_objects = xfs_qm_shrink_count;
+	qinf->qi_shrinker.scan_objects = xfs_qm_shrink_scan;
 	qinf->qi_shrinker.seeks = DEFAULT_SEEKS;
+	qinf->qi_shrinker.flags = SHRINKER_NUMA_AWARE;
 	register_shrinker(&qinf->qi_shrinker);
 	return 0;
 }
@@ -801,6 +941,7 @@ xfs_qm_destroy_quotainfo(
 	ASSERT(qi != NULL);
 
 	unregister_shrinker(&qi->qi_shrinker);
+	list_lru_destroy(&qi->qi_lru);
 
 	if (qi->qi_uquotaip) {
 		IRELE(qi->qi_uquotaip);
@@ -1599,132 +1740,6 @@ xfs_qm_dqfree_one(
 	xfs_qm_dqdestroy(dqp);
 }
 
-STATIC void
-xfs_qm_dqreclaim_one(
-	struct xfs_dquot	*dqp,
-	struct list_head	*buffer_list,
-	struct list_head	*dispose_list)
-{
-	struct xfs_mount	*mp = dqp->q_mount;
-	struct xfs_quotainfo	*qi = mp->m_quotainfo;
-	int			error;
-
-	if (!xfs_dqlock_nowait(dqp))
-		goto out_move_tail;
-
-	/*
-	 * This dquot has acquired a reference in the meantime remove it from
-	 * the freelist and try again.
-	 */
-	if (dqp->q_nrefs) {
-		xfs_dqunlock(dqp);
-
-		trace_xfs_dqreclaim_want(dqp);
-		XFS_STATS_INC(xs_qm_dqwants);
-
-		list_del_init(&dqp->q_lru);
-		qi->qi_lru_count--;
-		XFS_STATS_DEC(xs_qm_dquot_unused);
-		return;
-	}
-
-	/*
-	 * Try to grab the flush lock. If this dquot is in the process of
-	 * getting flushed to disk, we don't want to reclaim it.
-	 */
-	if (!xfs_dqflock_nowait(dqp))
-		goto out_unlock_move_tail;
-
-	if (XFS_DQ_IS_DIRTY(dqp)) {
-		struct xfs_buf	*bp = NULL;
-
-		trace_xfs_dqreclaim_dirty(dqp);
-
-		error = xfs_qm_dqflush(dqp, &bp);
-		if (error) {
-			xfs_warn(mp, "%s: dquot %p flush failed",
-				 __func__, dqp);
-			goto out_unlock_move_tail;
-		}
-
-		xfs_buf_delwri_queue(bp, buffer_list);
-		xfs_buf_relse(bp);
-		/*
-		 * Give the dquot another try on the freelist, as the
-		 * flushing will take some time.
-		 */
-		goto out_unlock_move_tail;
-	}
-	xfs_dqfunlock(dqp);
-
-	/*
-	 * Prevent lookups now that we are past the point of no return.
-	 */
-	dqp->dq_flags |= XFS_DQ_FREEING;
-	xfs_dqunlock(dqp);
-
-	ASSERT(dqp->q_nrefs == 0);
-	list_move_tail(&dqp->q_lru, dispose_list);
-	qi->qi_lru_count--;
-	XFS_STATS_DEC(xs_qm_dquot_unused);
-
-	trace_xfs_dqreclaim_done(dqp);
-	XFS_STATS_INC(xs_qm_dqreclaims);
-	return;
-
-	/*
-	 * Move the dquot to the tail of the list so that we don't spin on it.
-	 */
-out_unlock_move_tail:
-	xfs_dqunlock(dqp);
-out_move_tail:
-	list_move_tail(&dqp->q_lru, &qi->qi_lru_list);
-	trace_xfs_dqreclaim_busy(dqp);
-	XFS_STATS_INC(xs_qm_dqreclaim_misses);
-}
-
-STATIC int
-xfs_qm_shake(
-	struct shrinker		*shrink,
-	struct shrink_control	*sc)
-{
-	struct xfs_quotainfo	*qi =
-		container_of(shrink, struct xfs_quotainfo, qi_shrinker);
-	int			nr_to_scan = sc->nr_to_scan;
-	LIST_HEAD		(buffer_list);
-	LIST_HEAD		(dispose_list);
-	struct xfs_dquot	*dqp;
-	int			error;
-
-	if ((sc->gfp_mask & (__GFP_FS|__GFP_WAIT)) != (__GFP_FS|__GFP_WAIT))
-		return 0;
-	if (!nr_to_scan)
-		goto out;
-
-	mutex_lock(&qi->qi_lru_lock);
-	while (!list_empty(&qi->qi_lru_list)) {
-		if (nr_to_scan-- <= 0)
-			break;
-		dqp = list_first_entry(&qi->qi_lru_list, struct xfs_dquot,
-				       q_lru);
-		xfs_qm_dqreclaim_one(dqp, &buffer_list, &dispose_list);
-	}
-	mutex_unlock(&qi->qi_lru_lock);
-
-	error = xfs_buf_delwri_submit(&buffer_list);
-	if (error)
-		xfs_warn(NULL, "%s: dquot reclaim failed", __func__);
-
-	while (!list_empty(&dispose_list)) {
-		dqp = list_first_entry(&dispose_list, struct xfs_dquot, q_lru);
-		list_del_init(&dqp->q_lru);
-		xfs_qm_dqfree_one(dqp);
-	}
-
-out:
-	return (qi->qi_lru_count / 100) * sysctl_vfs_cache_pressure;
-}
-
 /*
  * Start a transaction and write the incore superblock changes to
  * disk. flags parameter indicates which fields have changed.

fs/xfs/xfs_qm.h

@@ -49,9 +49,7 @@ typedef struct xfs_quotainfo {
 	struct xfs_inode	*qi_uquotaip;	/* user quota inode */
 	struct xfs_inode	*qi_gquotaip;	/* group quota inode */
 	struct xfs_inode	*qi_pquotaip;	/* project quota inode */
-	struct list_head qi_lru_list;
-	struct mutex	 qi_lru_lock;
-	int		 qi_lru_count;
+	struct list_lru	 qi_lru;
 	int		 qi_dquots;
 	time_t		 qi_btimelimit;	 /* limit for blks timer */
 	time_t		 qi_itimelimit;	 /* limit for inodes timer */

fs/xfs/xfs_super.c

@@ -1535,19 +1535,21 @@ xfs_fs_mount(
 	return mount_bdev(fs_type, flags, dev_name, data, xfs_fs_fill_super);
 }
 
-static int
+static long
 xfs_fs_nr_cached_objects(
-	struct super_block	*sb)
+	struct super_block	*sb,
+	int			nid)
 {
 	return xfs_reclaim_inodes_count(XFS_M(sb));
 }
 
-static void
+static long
 xfs_fs_free_cached_objects(
 	struct super_block	*sb,
-	int			nr_to_scan)
+	long			nr_to_scan,
+	int			nid)
 {
-	xfs_reclaim_inodes_nr(XFS_M(sb), nr_to_scan);
+	return xfs_reclaim_inodes_nr(XFS_M(sb), nr_to_scan);
 }
 
 static const struct super_operations xfs_super_operations = {

include/linux/dcache.h

@@ -55,11 +55,11 @@ struct qstr {
 #define hashlen_len(hashlen)  ((u32)((hashlen) >> 32))
 
 struct dentry_stat_t {
-	int nr_dentry;
-	int nr_unused;
-	int age_limit;          /* age in seconds */
-	int want_pages;         /* pages requested by system */
-	int dummy[2];
+	long nr_dentry;
+	long nr_unused;
+	long age_limit;          /* age in seconds */
+	long want_pages;         /* pages requested by system */
+	long dummy[2];
 };
 extern struct dentry_stat_t dentry_stat;
 
@@ -395,4 +395,8 @@ static inline bool d_mountpoint(const struct dentry *dentry)
 
 extern int sysctl_vfs_cache_pressure;
 
+static inline unsigned long vfs_pressure_ratio(unsigned long val)
+{
+	return mult_frac(val, sysctl_vfs_cache_pressure, 100);
+}
 #endif	/* __LINUX_DCACHE_H */

include/linux/fs.h

@@ -10,6 +10,7 @@
 #include <linux/stat.h>
 #include <linux/cache.h>
 #include <linux/list.h>
+#include <linux/list_lru.h>
 #include <linux/llist.h>
 #include <linux/radix-tree.h>
 #include <linux/rbtree.h>
@@ -1269,15 +1270,6 @@ struct super_block {
 	struct list_head	s_files;
 #endif
 	struct list_head	s_mounts;	/* list of mounts; _not_ for fs use */
-	/* s_dentry_lru, s_nr_dentry_unused protected by dcache.c lru locks */
-	struct list_head	s_dentry_lru;	/* unused dentry lru */
-	int			s_nr_dentry_unused;	/* # of dentry on lru */
-
-	/* s_inode_lru_lock protects s_inode_lru and s_nr_inodes_unused */
-	spinlock_t		s_inode_lru_lock ____cacheline_aligned_in_smp;
-	struct list_head	s_inode_lru;		/* unused inode lru */
-	int			s_nr_inodes_unused;	/* # of inodes on lru */
-
 	struct block_device	*s_bdev;
 	struct backing_dev_info *s_bdi;
 	struct mtd_info		*s_mtd;
@@ -1331,11 +1323,14 @@ struct super_block {
 
 	/* AIO completions deferred from interrupt context */
 	struct workqueue_struct *s_dio_done_wq;
-};
 
-/* superblock cache pruning functions */
-extern void prune_icache_sb(struct super_block *sb, int nr_to_scan);
-extern void prune_dcache_sb(struct super_block *sb, int nr_to_scan);
+	/*
+	 * Keep the lru lists last in the structure so they always sit on their
+	 * own individual cachelines.
+	 */
+	struct list_lru		s_dentry_lru ____cacheline_aligned_in_smp;
+	struct list_lru		s_inode_lru ____cacheline_aligned_in_smp;
+};
 
 extern struct timespec current_fs_time(struct super_block *sb);
 
@@ -1629,8 +1624,8 @@ struct super_operations {
 	ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
 #endif
 	int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
-	int (*nr_cached_objects)(struct super_block *);
-	void (*free_cached_objects)(struct super_block *, int);
+	long (*nr_cached_objects)(struct super_block *, int);
+	long (*free_cached_objects)(struct super_block *, long, int);
 };
 
 /*
@@ -2494,7 +2489,6 @@ extern const struct file_operations generic_ro_fops;
 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
 
 extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
-extern int vfs_follow_link(struct nameidata *, const char *);
 extern int page_readlink(struct dentry *, char __user *, int);
 extern void *page_follow_link_light(struct dentry *, struct nameidata *);
 extern void page_put_link(struct dentry *, struct nameidata *, void *);

include/linux/list_lru.h

@@ -0,0 +1,131 @@
+/*
+ * Copyright (c) 2013 Red Hat, Inc. and Parallels Inc. All rights reserved.
+ * Authors: David Chinner and Glauber Costa
+ *
+ * Generic LRU infrastructure
+ */
+#ifndef _LRU_LIST_H
+#define _LRU_LIST_H
+
+#include <linux/list.h>
+#include <linux/nodemask.h>
+
+/* list_lru_walk_cb has to always return one of those */
+enum lru_status {
+	LRU_REMOVED,		/* item removed from list */
+	LRU_ROTATE,		/* item referenced, give another pass */
+	LRU_SKIP,		/* item cannot be locked, skip */
+	LRU_RETRY,		/* item not freeable. May drop the lock
+				   internally, but has to return locked. */
+};
+
+struct list_lru_node {
+	spinlock_t		lock;
+	struct list_head	list;
+	/* kept as signed so we can catch imbalance bugs */
+	long			nr_items;
+} ____cacheline_aligned_in_smp;
+
+struct list_lru {
+	struct list_lru_node	*node;
+	nodemask_t		active_nodes;
+};
+
+void list_lru_destroy(struct list_lru *lru);
+int list_lru_init(struct list_lru *lru);
+
+/**
+ * list_lru_add: add an element to the lru list's tail
+ * @list_lru: the lru pointer
+ * @item: the item to be added.
+ *
+ * If the element is already part of a list, this function returns doing
+ * nothing. Therefore the caller does not need to keep state about whether or
+ * not the element already belongs in the list and is allowed to lazy update
+ * it. Note however that this is valid for *a* list, not *this* list. If
+ * the caller organize itself in a way that elements can be in more than
+ * one type of list, it is up to the caller to fully remove the item from
+ * the previous list (with list_lru_del() for instance) before moving it
+ * to @list_lru
+ *
+ * Return value: true if the list was updated, false otherwise
+ */
+bool list_lru_add(struct list_lru *lru, struct list_head *item);
+
+/**
+ * list_lru_del: delete an element to the lru list
+ * @list_lru: the lru pointer
+ * @item: the item to be deleted.
+ *
+ * This function works analogously as list_lru_add in terms of list
+ * manipulation. The comments about an element already pertaining to
+ * a list are also valid for list_lru_del.
+ *
+ * Return value: true if the list was updated, false otherwise
+ */
+bool list_lru_del(struct list_lru *lru, struct list_head *item);
+
+/**
+ * list_lru_count_node: return the number of objects currently held by @lru
+ * @lru: the lru pointer.
+ * @nid: the node id to count from.
+ *
+ * Always return a non-negative number, 0 for empty lists. There is no
+ * guarantee that the list is not updated while the count is being computed.
+ * Callers that want such a guarantee need to provide an outer lock.
+ */
+unsigned long list_lru_count_node(struct list_lru *lru, int nid);
+static inline unsigned long list_lru_count(struct list_lru *lru)
+{
+	long count = 0;
+	int nid;
+
+	for_each_node_mask(nid, lru->active_nodes)
+		count += list_lru_count_node(lru, nid);
+
+	return count;
+}
+
+typedef enum lru_status
+(*list_lru_walk_cb)(struct list_head *item, spinlock_t *lock, void *cb_arg);
+/**
+ * list_lru_walk_node: walk a list_lru, isolating and disposing freeable items.
+ * @lru: the lru pointer.
+ * @nid: the node id to scan from.
+ * @isolate: callback function that is resposible for deciding what to do with
+ *  the item currently being scanned
+ * @cb_arg: opaque type that will be passed to @isolate
+ * @nr_to_walk: how many items to scan.
+ *
+ * This function will scan all elements in a particular list_lru, calling the
+ * @isolate callback for each of those items, along with the current list
+ * spinlock and a caller-provided opaque. The @isolate callback can choose to
+ * drop the lock internally, but *must* return with the lock held. The callback
+ * will return an enum lru_status telling the list_lru infrastructure what to
+ * do with the object being scanned.
+ *
+ * Please note that nr_to_walk does not mean how many objects will be freed,
+ * just how many objects will be scanned.
+ *
+ * Return value: the number of objects effectively removed from the LRU.
+ */
+unsigned long list_lru_walk_node(struct list_lru *lru, int nid,
+				 list_lru_walk_cb isolate, void *cb_arg,
+				 unsigned long *nr_to_walk);
+
+static inline unsigned long
+list_lru_walk(struct list_lru *lru, list_lru_walk_cb isolate,
+	      void *cb_arg, unsigned long nr_to_walk)
+{
+	long isolated = 0;
+	int nid;
+
+	for_each_node_mask(nid, lru->active_nodes) {
+		isolated += list_lru_walk_node(lru, nid, isolate,
+					       cb_arg, &nr_to_walk);
+		if (nr_to_walk <= 0)
+			break;
+	}
+	return isolated;
+}
+#endif /* _LRU_LIST_H */

include/linux/shrinker.h

@@ -4,39 +4,67 @@
 /*
  * 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.
  */
 struct shrink_control {
 	gfp_t gfp_mask;
 
-	/* How many slab objects shrinker() should scan and try to reclaim */
+	/*
+	 * How many objects scan_objects should scan and try to reclaim.
+	 * This is reset before every call, so it is safe for callees
+	 * to modify.
+	 */
 	unsigned long nr_to_scan;
+
+	/* shrink from these nodes */
+	nodemask_t nodes_to_scan;
+	/* current node being shrunk (for NUMA aware shrinkers) */
+	int nid;
 };
 
+#define SHRINK_STOP (~0UL)
 /*
  * A callback you can register to apply pressure to ageable caches.
  *
- * '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.
+ * @flags determine the shrinker abilities, like numa awareness
  */
 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 */
+	unsigned long flags;
 
 	/* These are for internal use */
 	struct list_head list;
-	atomic_long_t nr_in_batch; /* objs pending delete */
+	/* objs pending delete, per node */
+	atomic_long_t *nr_deferred;
 };
 #define DEFAULT_SEEKS 2 /* A good number if you don't know better. */
-extern void register_shrinker(struct shrinker *);
+
+/* Flags */
+#define SHRINKER_NUMA_AWARE (1 << 0)
+
+extern int register_shrinker(struct shrinker *);
 extern void unregister_shrinker(struct shrinker *);
 #endif

include/trace/events/vmscan.h

@@ -202,7 +202,7 @@ TRACE_EVENT(mm_shrink_slab_start,
 
 	TP_fast_assign(
 		__entry->shr = shr;
-		__entry->shrink = shr->shrink;
+		__entry->shrink = shr->scan_objects;
 		__entry->nr_objects_to_shrink = nr_objects_to_shrink;
 		__entry->gfp_flags = sc->gfp_mask;
 		__entry->pgs_scanned = pgs_scanned;
@@ -241,7 +241,7 @@ TRACE_EVENT(mm_shrink_slab_end,
 
 	TP_fast_assign(
 		__entry->shr = shr;
-		__entry->shrink = shr->shrink;
+		__entry->shrink = shr->scan_objects;
 		__entry->unused_scan = unused_scan_cnt;
 		__entry->new_scan = new_scan_cnt;
 		__entry->retval = shrinker_retval;

include/uapi/linux/fs.h

@@ -49,9 +49,9 @@ struct files_stat_struct {
 };
 
 struct inodes_stat_t {
-	int nr_inodes;
-	int nr_unused;
-	int dummy[5];		/* padding for sysctl ABI compatibility */
+	long nr_inodes;
+	long nr_unused;
+	long dummy[5];		/* padding for sysctl ABI compatibility */
 };
 
 

kernel/sysctl.c

@@ -1471,14 +1471,14 @@ static struct ctl_table fs_table[] = {
 	{
 		.procname	= "inode-nr",
 		.data		= &inodes_stat,
-		.maxlen		= 2*sizeof(int),
+		.maxlen		= 2*sizeof(long),
 		.mode		= 0444,
 		.proc_handler	= proc_nr_inodes,
 	},
 	{
 		.procname	= "inode-state",
 		.data		= &inodes_stat,
-		.maxlen		= 7*sizeof(int),
+		.maxlen		= 7*sizeof(long),
 		.mode		= 0444,
 		.proc_handler	= proc_nr_inodes,
 	},
@@ -1508,7 +1508,7 @@ static struct ctl_table fs_table[] = {
 	{
 		.procname	= "dentry-state",
 		.data		= &dentry_stat,
-		.maxlen		= 6*sizeof(int),
+		.maxlen		= 6*sizeof(long),
 		.mode		= 0444,
 		.proc_handler	= proc_nr_dentry,
 	},

mm/Makefile

@@ -17,7 +17,7 @@ obj-y			:= filemap.o mempool.o oom_kill.o fadvise.o \
 			   util.o mmzone.o vmstat.o backing-dev.o \
 			   mm_init.o mmu_context.o percpu.o slab_common.o \
 			   compaction.o balloon_compaction.o \
-			   interval_tree.o $(mmu-y)
+			   interval_tree.o list_lru.o $(mmu-y)
 
 obj-y += init-mm.o
 

mm/huge_memory.c

@@ -211,24 +211,29 @@ static void put_huge_zero_page(void)
 	BUG_ON(atomic_dec_and_test(&huge_zero_refcount));
 }
 
-static int shrink_huge_zero_page(struct shrinker *shrink,
-		struct shrink_control *sc)
+static unsigned long shrink_huge_zero_page_count(struct shrinker *shrink,
+					struct shrink_control *sc)
 {
-	if (!sc->nr_to_scan)
-		/* we can free zero page only if last reference remains */
-		return atomic_read(&huge_zero_refcount) == 1 ? HPAGE_PMD_NR : 0;
+	/* we can free zero page only if last reference remains */
+	return atomic_read(&huge_zero_refcount) == 1 ? HPAGE_PMD_NR : 0;
+}
 
+static unsigned long shrink_huge_zero_page_scan(struct shrinker *shrink,
+				       struct shrink_control *sc)
+{
 	if (atomic_cmpxchg(&huge_zero_refcount, 1, 0) == 1) {
 		struct page *zero_page = xchg(&huge_zero_page, NULL);
 		BUG_ON(zero_page == NULL);
 		__free_page(zero_page);
+		return HPAGE_PMD_NR;
 	}
 
 	return 0;
 }
 
 static struct shrinker huge_zero_page_shrinker = {
-	.shrink = shrink_huge_zero_page,
+	.count_objects = shrink_huge_zero_page_count,
+	.scan_objects = shrink_huge_zero_page_scan,
 	.seeks = DEFAULT_SEEKS,
 };
 

mm/list_lru.c

@@ -0,0 +1,139 @@
+/*
+ * Copyright (c) 2013 Red Hat, Inc. and Parallels Inc. All rights reserved.
+ * Authors: David Chinner and Glauber Costa
+ *
+ * Generic LRU infrastructure
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/list_lru.h>
+#include <linux/slab.h>
+
+bool list_lru_add(struct list_lru *lru, struct list_head *item)
+{
+	int nid = page_to_nid(virt_to_page(item));
+	struct list_lru_node *nlru = &lru->node[nid];
+
+	spin_lock(&nlru->lock);
+	WARN_ON_ONCE(nlru->nr_items < 0);
+	if (list_empty(item)) {
+		list_add_tail(item, &nlru->list);
+		if (nlru->nr_items++ == 0)
+			node_set(nid, lru->active_nodes);
+		spin_unlock(&nlru->lock);
+		return true;
+	}
+	spin_unlock(&nlru->lock);
+	return false;
+}
+EXPORT_SYMBOL_GPL(list_lru_add);
+
+bool list_lru_del(struct list_lru *lru, struct list_head *item)
+{
+	int nid = page_to_nid(virt_to_page(item));
+	struct list_lru_node *nlru = &lru->node[nid];
+
+	spin_lock(&nlru->lock);
+	if (!list_empty(item)) {
+		list_del_init(item);
+		if (--nlru->nr_items == 0)
+			node_clear(nid, lru->active_nodes);
+		WARN_ON_ONCE(nlru->nr_items < 0);
+		spin_unlock(&nlru->lock);
+		return true;
+	}
+	spin_unlock(&nlru->lock);
+	return false;
+}
+EXPORT_SYMBOL_GPL(list_lru_del);
+
+unsigned long
+list_lru_count_node(struct list_lru *lru, int nid)
+{
+	unsigned long count = 0;
+	struct list_lru_node *nlru = &lru->node[nid];
+
+	spin_lock(&nlru->lock);
+	WARN_ON_ONCE(nlru->nr_items < 0);
+	count += nlru->nr_items;
+	spin_unlock(&nlru->lock);
+
+	return count;
+}
+EXPORT_SYMBOL_GPL(list_lru_count_node);
+
+unsigned long
+list_lru_walk_node(struct list_lru *lru, int nid, list_lru_walk_cb isolate,
+		   void *cb_arg, unsigned long *nr_to_walk)
+{
+
+	struct list_lru_node	*nlru = &lru->node[nid];
+	struct list_head *item, *n;
+	unsigned long isolated = 0;
+
+	spin_lock(&nlru->lock);
+restart:
+	list_for_each_safe(item, n, &nlru->list) {
+		enum lru_status ret;
+
+		/*
+		 * decrement nr_to_walk first so that we don't livelock if we
+		 * get stuck on large numbesr of LRU_RETRY items
+		 */
+		if (--(*nr_to_walk) == 0)
+			break;
+
+		ret = isolate(item, &nlru->lock, cb_arg);
+		switch (ret) {
+		case LRU_REMOVED:
+			if (--nlru->nr_items == 0)
+				node_clear(nid, lru->active_nodes);
+			WARN_ON_ONCE(nlru->nr_items < 0);
+			isolated++;
+			break;
+		case LRU_ROTATE:
+			list_move_tail(item, &nlru->list);
+			break;
+		case LRU_SKIP:
+			break;
+		case LRU_RETRY:
+			/*
+			 * The lru lock has been dropped, our list traversal is
+			 * now invalid and so we have to restart from scratch.
+			 */
+			goto restart;
+		default:
+			BUG();
+		}
+	}
+
+	spin_unlock(&nlru->lock);
+	return isolated;
+}
+EXPORT_SYMBOL_GPL(list_lru_walk_node);
+
+int list_lru_init(struct list_lru *lru)
+{
+	int i;
+	size_t size = sizeof(*lru->node) * nr_node_ids;
+
+	lru->node = kzalloc(size, GFP_KERNEL);
+	if (!lru->node)
+		return -ENOMEM;
+
+	nodes_clear(lru->active_nodes);
+	for (i = 0; i < nr_node_ids; i++) {
+		spin_lock_init(&lru->node[i].lock);
+		INIT_LIST_HEAD(&lru->node[i].list);
+		lru->node[i].nr_items = 0;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(list_lru_init);
+
+void list_lru_destroy(struct list_lru *lru)
+{
+	kfree(lru->node);
+}
+EXPORT_SYMBOL_GPL(list_lru_destroy);

mm/memory-failure.c

@@ -248,10 +248,12 @@ void shake_page(struct page *p, int access)
 	 */
 	if (access) {
 		int nr;
+		int nid = page_to_nid(p);
 		do {
 			struct shrink_control shrink = {
 				.gfp_mask = GFP_KERNEL,
 			};
+			node_set(nid, shrink.nodes_to_scan);
 
 			nr = shrink_slab(&shrink, 1000, 1000);
 			if (page_count(p) == 1)

mm/vmscan.c

@@ -174,14 +174,31 @@ static unsigned long get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 }
 
 /*
- * Add a shrinker callback to be called from the vm
+ * Add a shrinker callback to be called from the vm.
  */
-void register_shrinker(struct shrinker *shrinker)
+int register_shrinker(struct shrinker *shrinker)
 {
-	atomic_long_set(&shrinker->nr_in_batch, 0);
+	size_t size = sizeof(*shrinker->nr_deferred);
+
+	/*
+	 * If we only have one possible node in the system anyway, save
+	 * ourselves the trouble and disable NUMA aware behavior. This way we
+	 * will save memory and some small loop time later.
+	 */
+	if (nr_node_ids == 1)
+		shrinker->flags &= ~SHRINKER_NUMA_AWARE;
+
+	if (shrinker->flags & SHRINKER_NUMA_AWARE)
+		size *= nr_node_ids;
+
+	shrinker->nr_deferred = kzalloc(size, GFP_KERNEL);
+	if (!shrinker->nr_deferred)
+		return -ENOMEM;
+
 	down_write(&shrinker_rwsem);
 	list_add_tail(&shrinker->list, &shrinker_list);
 	up_write(&shrinker_rwsem);
+	return 0;
 }
 EXPORT_SYMBOL(register_shrinker);
 
@@ -196,15 +213,102 @@ void unregister_shrinker(struct shrinker *shrinker)
 }
 EXPORT_SYMBOL(unregister_shrinker);
 
-static inline int do_shrinker_shrink(struct shrinker *shrinker,
-				     struct shrink_control *sc,
-				     unsigned long nr_to_scan)
-{
-	sc->nr_to_scan = nr_to_scan;
-	return (*shrinker->shrink)(shrinker, sc);
+#define SHRINK_BATCH 128
+
+static unsigned long
+shrink_slab_node(struct shrink_control *shrinkctl, struct shrinker *shrinker,
+		 unsigned long nr_pages_scanned, unsigned long lru_pages)
+{
+	unsigned long freed = 0;
+	unsigned long long delta;
+	long total_scan;
+	long max_pass;
+	long nr;
+	long new_nr;
+	int nid = shrinkctl->nid;
+	long batch_size = shrinker->batch ? shrinker->batch
+					  : SHRINK_BATCH;
+
+	max_pass = shrinker->count_objects(shrinker, shrinkctl);
+	if (max_pass == 0)
+		return 0;
+
+	/*
+	 * copy the current shrinker scan count into a local variable
+	 * and zero it so that other concurrent shrinker invocations
+	 * don't also do this scanning work.
+	 */
+	nr = atomic_long_xchg(&shrinker->nr_deferred[nid], 0);
+
+	total_scan = nr;
+	delta = (4 * nr_pages_scanned) / shrinker->seeks;
+	delta *= max_pass;
+	do_div(delta, lru_pages + 1);
+	total_scan += delta;
+	if (total_scan < 0) {
+		printk(KERN_ERR
+		"shrink_slab: %pF negative objects to delete nr=%ld\n",
+		       shrinker->scan_objects, total_scan);
+		total_scan = max_pass;
+	}
+
+	/*
+	 * We need to avoid excessive windup on filesystem shrinkers
+	 * due to large numbers of GFP_NOFS allocations causing the
+	 * shrinkers to return -1 all the time. This results in a large
+	 * nr being built up so when a shrink that can do some work
+	 * comes along it empties the entire cache due to nr >>>
+	 * max_pass.  This is bad for sustaining a working set in
+	 * memory.
+	 *
+	 * Hence only allow the shrinker to scan the entire cache when
+	 * a large delta change is calculated directly.
+	 */
+	if (delta < max_pass / 4)
+		total_scan = min(total_scan, max_pass / 2);
+
+	/*
+	 * Avoid risking looping forever due to too large nr value:
+	 * never try to free more than twice the estimate number of
+	 * freeable entries.
+	 */
+	if (total_scan > max_pass * 2)
+		total_scan = max_pass * 2;
+
+	trace_mm_shrink_slab_start(shrinker, shrinkctl, nr,
+				nr_pages_scanned, lru_pages,
+				max_pass, delta, total_scan);
+
+	while (total_scan >= batch_size) {
+		unsigned long ret;
+
+		shrinkctl->nr_to_scan = batch_size;
+		ret = shrinker->scan_objects(shrinker, shrinkctl);
+		if (ret == SHRINK_STOP)
+			break;
+		freed += ret;
+
+		count_vm_events(SLABS_SCANNED, batch_size);
+		total_scan -= batch_size;
+
+		cond_resched();
+	}
+
+	/*
+	 * move the unused scan count back into the shrinker in a
+	 * manner that handles concurrent updates. If we exhausted the
+	 * scan, there is no need to do an update.
+	 */
+	if (total_scan > 0)
+		new_nr = atomic_long_add_return(total_scan,
+						&shrinker->nr_deferred[nid]);
+	else
+		new_nr = atomic_long_read(&shrinker->nr_deferred[nid]);
+
+	trace_mm_shrink_slab_end(shrinker, freed, nr, new_nr);
+	return freed;
 }
 
-#define SHRINK_BATCH 128
 /*
  * Call the shrink functions to age shrinkable caches
  *
@@ -224,115 +328,45 @@ static inline int do_shrinker_shrink(struct shrinker *shrinker,
  *
  * Returns the number of slab objects which we shrunk.
  */
-unsigned long shrink_slab(struct shrink_control *shrink,
+unsigned long shrink_slab(struct shrink_control *shrinkctl,
 			  unsigned long nr_pages_scanned,
 			  unsigned long lru_pages)
 {
 	struct shrinker *shrinker;
-	unsigned long ret = 0;
+	unsigned long freed = 0;
 
 	if (nr_pages_scanned == 0)
 		nr_pages_scanned = SWAP_CLUSTER_MAX;
 
 	if (!down_read_trylock(&shrinker_rwsem)) {
-		/* Assume we'll be able to shrink next time */
-		ret = 1;
+		/*
+		 * If we would return 0, our callers would understand that we
+		 * have nothing else to shrink and give up trying. By returning
+		 * 1 we keep it going and assume we'll be able to shrink next
+		 * time.
+		 */
+		freed = 1;
 		goto out;
 	}
 
 	list_for_each_entry(shrinker, &shrinker_list, list) {
-		unsigned long long delta;
-		long total_scan;
-		long max_pass;
-		int shrink_ret = 0;
-		long nr;
-		long new_nr;
-		long batch_size = shrinker->batch ? shrinker->batch
-						  : SHRINK_BATCH;
-
-		max_pass = do_shrinker_shrink(shrinker, shrink, 0);
-		if (max_pass <= 0)
-			continue;
-
-		/*
-		 * copy the current shrinker scan count into a local variable
-		 * and zero it so that other concurrent shrinker invocations
-		 * don't also do this scanning work.
-		 */
-		nr = atomic_long_xchg(&shrinker->nr_in_batch, 0);
-
-		total_scan = nr;
-		delta = (4 * nr_pages_scanned) / shrinker->seeks;
-		delta *= max_pass;
-		do_div(delta, lru_pages + 1);
-		total_scan += delta;
-		if (total_scan < 0) {
-			printk(KERN_ERR "shrink_slab: %pF negative objects to "
-			       "delete nr=%ld\n",
-			       shrinker->shrink, total_scan);
-			total_scan = max_pass;
-		}
-
-		/*
-		 * We need to avoid excessive windup on filesystem shrinkers
-		 * due to large numbers of GFP_NOFS allocations causing the
-		 * shrinkers to return -1 all the time. This results in a large
-		 * nr being built up so when a shrink that can do some work
-		 * comes along it empties the entire cache due to nr >>>
-		 * max_pass.  This is bad for sustaining a working set in
-		 * memory.
-		 *
-		 * Hence only allow the shrinker to scan the entire cache when
-		 * a large delta change is calculated directly.
-		 */
-		if (delta < max_pass / 4)
-			total_scan = min(total_scan, max_pass / 2);
-
-		/*
-		 * Avoid risking looping forever due to too large nr value:
-		 * never try to free more than twice the estimate number of
-		 * freeable entries.
-		 */
-		if (total_scan > max_pass * 2)
-			total_scan = max_pass * 2;
-
-		trace_mm_shrink_slab_start(shrinker, shrink, nr,
-					nr_pages_scanned, lru_pages,
-					max_pass, delta, total_scan);
-
-		while (total_scan >= batch_size) {
-			int nr_before;
+		for_each_node_mask(shrinkctl->nid, shrinkctl->nodes_to_scan) {
+			if (!node_online(shrinkctl->nid))
+				continue;
 
-			nr_before = do_shrinker_shrink(shrinker, shrink, 0);
-			shrink_ret = do_shrinker_shrink(shrinker, shrink,
-							batch_size);
-			if (shrink_ret == -1)
+			if (!(shrinker->flags & SHRINKER_NUMA_AWARE) &&
+			    (shrinkctl->nid != 0))
 				break;
-			if (shrink_ret < nr_before)
-				ret += nr_before - shrink_ret;
-			count_vm_events(SLABS_SCANNED, batch_size);
-			total_scan -= batch_size;
 
-			cond_resched();
-		}
+			freed += shrink_slab_node(shrinkctl, shrinker,
+				 nr_pages_scanned, lru_pages);
 
-		/*
-		 * move the unused scan count back into the shrinker in a
-		 * manner that handles concurrent updates. If we exhausted the
-		 * scan, there is no need to do an update.
-		 */
-		if (total_scan > 0)
-			new_nr = atomic_long_add_return(total_scan,
-					&shrinker->nr_in_batch);
-		else
-			new_nr = atomic_long_read(&shrinker->nr_in_batch);
-
-		trace_mm_shrink_slab_end(shrinker, shrink_ret, nr, new_nr);
+		}
 	}
 	up_read(&shrinker_rwsem);
 out:
 	cond_resched();
-	return ret;
+	return freed;
 }
 
 static inline int is_page_cache_freeable(struct page *page)
@@ -2368,12 +2402,16 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
 		 */
 		if (global_reclaim(sc)) {
 			unsigned long lru_pages = 0;
+
+			nodes_clear(shrink->nodes_to_scan);
 			for_each_zone_zonelist(zone, z, zonelist,
 					gfp_zone(sc->gfp_mask)) {
 				if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL))
 					continue;
 
 				lru_pages += zone_reclaimable_pages(zone);
+				node_set(zone_to_nid(zone),
+					 shrink->nodes_to_scan);
 			}
 
 			shrink_slab(shrink, sc->nr_scanned, lru_pages);
@@ -2829,6 +2867,8 @@ static bool kswapd_shrink_zone(struct zone *zone,
 		return true;
 
 	shrink_zone(zone, sc);
+	nodes_clear(shrink.nodes_to_scan);
+	node_set(zone_to_nid(zone), shrink.nodes_to_scan);
 
 	reclaim_state->reclaimed_slab = 0;
 	shrink_slab(&shrink, sc->nr_scanned, lru_pages);
@@ -3520,10 +3560,9 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 		 * number of slab pages and shake the slab until it is reduced
 		 * by the same nr_pages that we used for reclaiming unmapped
 		 * pages.
-		 *
-		 * Note that shrink_slab will free memory on all zones and may
-		 * take a long time.
 		 */
+		nodes_clear(shrink.nodes_to_scan);
+		node_set(zone_to_nid(zone), shrink.nodes_to_scan);
 		for (;;) {
 			unsigned long lru_pages = zone_reclaimable_pages(zone);
 

net/sunrpc/auth.c

@@ -434,12 +434,13 @@ EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
 /*
  * Remove stale credentials. Avoid sleeping inside the loop.
  */
-static int
+static long
 rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
 {
 	spinlock_t *cache_lock;
 	struct rpc_cred *cred, *next;
 	unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
+	long freed = 0;
 
 	list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) {
 
@@ -451,10 +452,11 @@ rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
 		 */
 		if (time_in_range(cred->cr_expire, expired, jiffies) &&
 		    test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0)
-			return 0;
+			break;
 
 		list_del_init(&cred->cr_lru);
 		number_cred_unused--;
+		freed++;
 		if (atomic_read(&cred->cr_count) != 0)
 			continue;
 
@@ -467,29 +469,39 @@ rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
 		}
 		spin_unlock(cache_lock);
 	}
-	return (number_cred_unused / 100) * sysctl_vfs_cache_pressure;
+	return freed;
 }
 
 /*
  * Run memory cache shrinker.
  */
-static int
-rpcauth_cache_shrinker(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long
+rpcauth_cache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
+
 {
 	LIST_HEAD(free);
-	int res;
-	int nr_to_scan = sc->nr_to_scan;
-	gfp_t gfp_mask = sc->gfp_mask;
+	unsigned long freed;
+
+	if ((sc->gfp_mask & GFP_KERNEL) != GFP_KERNEL)
+		return SHRINK_STOP;
 
-	if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
-		return (nr_to_scan == 0) ? 0 : -1;
+	/* nothing left, don't come back */
 	if (list_empty(&cred_unused))
-		return 0;
+		return SHRINK_STOP;
+
 	spin_lock(&rpc_credcache_lock);
-	res = rpcauth_prune_expired(&free, nr_to_scan);
+	freed = rpcauth_prune_expired(&free, sc->nr_to_scan);
 	spin_unlock(&rpc_credcache_lock);
 	rpcauth_destroy_credlist(&free);
-	return res;
+
+	return freed;
+}
+
+static unsigned long
+rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+
+{
+	return (number_cred_unused / 100) * sysctl_vfs_cache_pressure;
 }
 
 /*
@@ -805,7 +817,8 @@ rpcauth_uptodatecred(struct rpc_task *task)
 }
 
 static struct shrinker rpc_cred_shrinker = {
-	.shrink = rpcauth_cache_shrinker,
+	.count_objects = rpcauth_cache_shrink_count,
+	.scan_objects = rpcauth_cache_shrink_scan,
 	.seeks = DEFAULT_SEEKS,
 };