3 files changed, 26 insertions, 54 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 6e16c1867959..96c10934bb96 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1268,6 +1268,7 @@ struct ext4_sb_info {
         atomic_t s_mb_preallocated;
         atomic_t s_mb_discarded;
         atomic_t s_lock_busy;
+        atomic_t s_extent_cache_cnt;
 
         /* locality groups */
         struct ext4_locality_group __percpu *s_locality_groups;
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index f768f4a98a2b..27fcdd2b2607 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -147,11 +147,12 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
                               ext4_lblk_t end);
 static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
                                        int nr_to_scan);
-static int ext4_es_reclaim_extents_count(struct super_block *sb);
 
 int __init ext4_init_es(void)
 {
-        ext4_es_cachep = KMEM_CACHE(extent_status, SLAB_RECLAIM_ACCOUNT);
+        ext4_es_cachep = kmem_cache_create("ext4_extent_status",
+                                           sizeof(struct extent_status),
+                                           0, (SLAB_RECLAIM_ACCOUNT), NULL);
         if (ext4_es_cachep == NULL)
                 return -ENOMEM;
         return 0;
@@ -302,8 +303,10 @@ ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len,
         /*
          * We don't count delayed extent because we never try to reclaim them
          */
-        if (!ext4_es_is_delayed(es))
+        if (!ext4_es_is_delayed(es)) {
                 EXT4_I(inode)->i_es_lru_nr++;
+                atomic_inc(&EXT4_SB(inode->i_sb)->s_extent_cache_cnt);
+        }
 
         return es;
 }
@@ -314,6 +317,7 @@ static void ext4_es_free_extent(struct inode *inode, struct extent_status *es)
         if (!ext4_es_is_delayed(es)) {
                 BUG_ON(EXT4_I(inode)->i_es_lru_nr == 0);
                 EXT4_I(inode)->i_es_lru_nr--;
+                atomic_dec(&EXT4_SB(inode->i_sb)->s_extent_cache_cnt);
         }
 
         kmem_cache_free(ext4_es_cachep, es);
@@ -674,10 +678,11 @@ static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
         int nr_to_scan = sc->nr_to_scan;
         int ret, nr_shrunk = 0;
 
-        trace_ext4_es_shrink_enter(sbi->s_sb, nr_to_scan);
+        ret = atomic_read(&sbi->s_extent_cache_cnt);
+        trace_ext4_es_shrink_enter(sbi->s_sb, nr_to_scan, ret);
 
         if (!nr_to_scan)
-                return ext4_es_reclaim_extents_count(sbi->s_sb);
+                return ret;
 
         INIT_LIST_HEAD(&scanned);
 
@@ -705,9 +710,10 @@ static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
         }
         list_splice_tail(&scanned, &sbi->s_es_lru);
         spin_unlock(&sbi->s_es_lru_lock);
-        trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk);
 
-        return ext4_es_reclaim_extents_count(sbi->s_sb);
+        ret = atomic_read(&sbi->s_extent_cache_cnt);
+        trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk, ret);
+        return ret;
 }
 
 void ext4_es_register_shrinker(struct super_block *sb)
@@ -751,25 +757,6 @@ void ext4_es_lru_del(struct inode *inode)
         spin_unlock(&sbi->s_es_lru_lock);
 }
 
-static int ext4_es_reclaim_extents_count(struct super_block *sb)
-{
-        struct ext4_sb_info *sbi = EXT4_SB(sb);
-        struct ext4_inode_info *ei;
-        struct list_head *cur;
-        int nr_cached = 0;
-
-        spin_lock(&sbi->s_es_lru_lock);
-        list_for_each(cur, &sbi->s_es_lru) {
-                ei = list_entry(cur, struct ext4_inode_info, i_es_lru);
-                read_lock(&ei->i_es_lock);
-                nr_cached += ei->i_es_lru_nr;
-                read_unlock(&ei->i_es_lock);
-        }
-        spin_unlock(&sbi->s_es_lru_lock);
-        trace_ext4_es_reclaim_extents_count(sb, nr_cached);
-        return nr_cached;
-}
-
 static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
                                        int nr_to_scan)
 {
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index c0457c0d1a68..4ee471003859 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -2255,64 +2255,48 @@ TRACE_EVENT(ext4_es_lookup_extent_exit,
                   __entry->found ? __entry->status : 0)
 );
 
-TRACE_EVENT(ext4_es_reclaim_extents_count,
-        TP_PROTO(struct super_block *sb, int nr_cached),
-
-        TP_ARGS(sb, nr_cached),
-
-        TP_STRUCT__entry(
-                __field(        dev_t,  dev                     )
-                __field(        int,    nr_cached               )
-        ),
-
-        TP_fast_assign(
-                __entry->dev            = sb->s_dev;
-                __entry->nr_cached      = nr_cached;
-        ),
-
-        TP_printk("dev %d,%d cached objects nr %d",
-                  MAJOR(__entry->dev), MINOR(__entry->dev),
-                  __entry->nr_cached)
-);
-
 TRACE_EVENT(ext4_es_shrink_enter,
-        TP_PROTO(struct super_block *sb, int nr_to_scan),
+        TP_PROTO(struct super_block *sb, int nr_to_scan, int cache_cnt),
 
-        TP_ARGS(sb, nr_to_scan),
+        TP_ARGS(sb, nr_to_scan, cache_cnt),
 
         TP_STRUCT__entry(
                 __field(        dev_t,  dev                     )
                 __field(        int,    nr_to_scan              )
+                __field(        int,    cache_cnt               )
         ),
 
         TP_fast_assign(
                 __entry->dev            = sb->s_dev;
                 __entry->nr_to_scan     = nr_to_scan;
+                __entry->cache_cnt      = cache_cnt;
         ),
 
-        TP_printk("dev %d,%d nr to scan %d",
+        TP_printk("dev %d,%d nr_to_scan %d cache_cnt %d",
                   MAJOR(__entry->dev), MINOR(__entry->dev),
-                  __entry->nr_to_scan)
+                  __entry->nr_to_scan, __entry->cache_cnt)
 );
 
 TRACE_EVENT(ext4_es_shrink_exit,
-        TP_PROTO(struct super_block *sb, int shrunk_nr),
+        TP_PROTO(struct super_block *sb, int shrunk_nr, int cache_cnt),
 
-        TP_ARGS(sb, shrunk_nr),
+        TP_ARGS(sb, shrunk_nr, cache_cnt),
 
         TP_STRUCT__entry(
                 __field(        dev_t,  dev                     )
                 __field(        int,    shrunk_nr               )
+                __field(        int,    cache_cnt               )
         ),
 
         TP_fast_assign(
                 __entry->dev            = sb->s_dev;
                 __entry->shrunk_nr      = shrunk_nr;
+                __entry->cache_cnt      = cache_cnt;
         ),
 
-        TP_printk("dev %d,%d nr to scan %d",
+        TP_printk("dev %d,%d shrunk_nr %d cache_cnt %d",
                   MAJOR(__entry->dev), MINOR(__entry->dev),
-                  __entry->shrunk_nr)
+                  __entry->shrunk_nr, __entry->cache_cnt)
 );
 
 #endif /* _TRACE_EXT4_H */