[PATCH 1/2] f2fs: use atomic variable for total_extent_tree

[PATCH 1/2] f2fs: use atomic variable for total_extent_tree

[Jaegeuk Kim]

It would be better to use atomic variable for total_extent_tree.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/debug.c        | 5 +++--
 fs/f2fs/extent_cache.c | 8 ++++----
 fs/f2fs/f2fs.h         | 2 +-
 fs/f2fs/node.c         | 3 ++-
 fs/f2fs/shrinker.c     | 3 ++-
 5 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index bb307e6..ed5dfcc 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -38,7 +38,7 @@ static void update_general_status(struct f2fs_sb_info *sbi)
 	si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
 	si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
 	si->total_ext = atomic64_read(&sbi->total_hit_ext);
-	si->ext_tree = sbi->total_ext_tree;
+	si->ext_tree = atomic_read(&sbi->total_ext_tree);
 	si->ext_node = atomic_read(&sbi->total_ext_node);
 	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
 	si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
@@ -193,7 +193,8 @@ get_cache:
 	si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
 	for (i = 0; i <= UPDATE_INO; i++)
 		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
-	si->cache_mem += sbi->total_ext_tree * sizeof(struct extent_tree);
+	si->cache_mem += atomic_read(&sbi->total_ext_tree) *
+						sizeof(struct extent_tree);
 	si->cache_mem += atomic_read(&sbi->total_ext_node) *
 						sizeof(struct extent_node);
 
diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index e86e9f1e..0e97d6af 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -70,7 +70,7 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
 		rwlock_init(&et->lock);
 		atomic_set(&et->refcount, 0);
 		et->count = 0;
-		sbi->total_ext_tree++;
+		atomic_inc(&sbi->total_ext_tree);
 	}
 	atomic_inc(&et->refcount);
 	up_write(&sbi->extent_tree_lock);
@@ -570,7 +570,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
 
 				radix_tree_delete(root, et->ino);
 				kmem_cache_free(extent_tree_slab, et);
-				sbi->total_ext_tree--;
+				atomic_dec(&sbi->total_ext_tree);
 				tree_cnt++;
 
 				if (node_cnt + tree_cnt >= nr_shrink)
@@ -663,7 +663,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
 	f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count);
 	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
 	kmem_cache_free(extent_tree_slab, et);
-	sbi->total_ext_tree--;
+	atomic_dec(&sbi->total_ext_tree);
 	up_write(&sbi->extent_tree_lock);
 
 	F2FS_I(inode)->extent_tree = NULL;
@@ -715,7 +715,7 @@ void init_extent_cache_info(struct f2fs_sb_info *sbi)
 	init_rwsem(&sbi->extent_tree_lock);
 	INIT_LIST_HEAD(&sbi->extent_list);
 	spin_lock_init(&sbi->extent_lock);
-	sbi->total_ext_tree = 0;
+	atomic_set(&sbi->total_ext_tree, 0);
 	atomic_set(&sbi->total_ext_node, 0);
 }
 
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 19beabe..a7f6191 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -762,7 +762,7 @@ struct f2fs_sb_info {
 	struct rw_semaphore extent_tree_lock;	/* locking extent radix tree */
 	struct list_head extent_list;		/* lru list for shrinker */
 	spinlock_t extent_lock;			/* locking extent lru list */
-	int total_ext_tree;			/* extent tree count */
+	atomic_t total_ext_tree;		/* extent tree count */
 	atomic_t total_ext_node;		/* extent info count */
 
 	/* basic filesystem units */
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index d842b19..6cc8ac7 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -65,7 +65,8 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
 				sizeof(struct ino_entry)) >> PAGE_CACHE_SHIFT;
 		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
 	} else if (type == EXTENT_CACHE) {
-		mem_size = (sbi->total_ext_tree * sizeof(struct extent_tree) +
+		mem_size = (atomic_read(&sbi->total_ext_tree) *
+				sizeof(struct extent_tree) +
 				atomic_read(&sbi->total_ext_node) *
 				sizeof(struct extent_node)) >> PAGE_CACHE_SHIFT;
 		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
index da0d8e0..a11e099 100644
--- a/fs/f2fs/shrinker.c
+++ b/fs/f2fs/shrinker.c
@@ -32,7 +32,8 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
 
 static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
 {
-	return sbi->total_ext_tree + atomic_read(&sbi->total_ext_node);
+	return atomic_read(&sbi->total_ext_tree) +
+				atomic_read(&sbi->total_ext_node);
 }
 
 unsigned long f2fs_shrink_count(struct shrinker *shrink,
-- 
2.5.4 (Apple Git-61)

[PATCH 2/2] f2fs: speed up shrinking extent tree entries

[Jaegeuk Kim]

If there is no candidates for shrinking slab entries, we don't need to traverse
any trees at all.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/extent_cache.c | 12 ++++++++++++
 fs/f2fs/f2fs.h         |  1 +
 fs/f2fs/shrinker.c     |  2 +-
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index 0e97d6af..32693af 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -71,6 +71,8 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
 		atomic_set(&et->refcount, 0);
 		et->count = 0;
 		atomic_inc(&sbi->total_ext_tree);
+	} else {
+		atomic_dec(&sbi->total_zombie_tree);
 	}
 	atomic_inc(&et->refcount);
 	up_write(&sbi->extent_tree_lock);
@@ -547,10 +549,14 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
 	unsigned int found;
 	unsigned int node_cnt = 0, tree_cnt = 0;
 	int remained;
+	bool do_free = false;
 
 	if (!test_opt(sbi, EXTENT_CACHE))
 		return 0;
 
+	if (!atomic_read(&sbi->total_zombie_tree))
+		goto free_node;
+
 	if (!down_write_trylock(&sbi->extent_tree_lock))
 		goto out;
 
@@ -580,6 +586,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
 	}
 	up_write(&sbi->extent_tree_lock);
 
+free_node:
 	/* 2. remove LRU extent entries */
 	if (!down_write_trylock(&sbi->extent_tree_lock))
 		goto out;
@@ -591,9 +598,13 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
 		if (!remained--)
 			break;
 		list_del_init(&en->list);
+		do_free = true;
 	}
 	spin_unlock(&sbi->extent_lock);
 
+	if (do_free == false)
+		goto unlock_out;
+
 	/*
 	 * reset ino for searching victims from beginning of global extent tree.
 	 */
@@ -651,6 +662,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
 
 	if (inode->i_nlink && !is_bad_inode(inode) && et->count) {
 		atomic_dec(&et->refcount);
+		atomic_dec(&sbi->total_zombie_tree);
 		return;
 	}
 
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index a7f6191..90fb970 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -763,6 +763,7 @@ struct f2fs_sb_info {
 	struct list_head extent_list;		/* lru list for shrinker */
 	spinlock_t extent_lock;			/* locking extent lru list */
 	atomic_t total_ext_tree;		/* extent tree count */
+	atomic_t total_zombie_tree;		/* extent zombie tree count */
 	atomic_t total_ext_node;		/* extent info count */
 
 	/* basic filesystem units */
diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
index a11e099..93606f2 100644
--- a/fs/f2fs/shrinker.c
+++ b/fs/f2fs/shrinker.c
@@ -32,7 +32,7 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
 
 static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
 {
-	return atomic_read(&sbi->total_ext_tree) +
+	return atomic_read(&sbi->total_zombie_tree) +
 				atomic_read(&sbi->total_ext_node);
 }
 
-- 
2.5.4 (Apple Git-61)


------------------------------------------------------------------------------

Re: [PATCH 2/2] f2fs: speed up shrinking extent tree entries

[Jaegeuk Kim]

On Mon, Dec 21, 2015 at 07:38:41PM -0800, Jaegeuk Kim wrote:
> If there is no candidates for shrinking slab entries, we don't need to traverse
> any trees at all.
> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>  fs/f2fs/extent_cache.c | 12 ++++++++++++
>  fs/f2fs/f2fs.h         |  1 +
>  fs/f2fs/shrinker.c     |  2 +-
>  3 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> index 0e97d6af..32693af 100644
> --- a/fs/f2fs/extent_cache.c
> +++ b/fs/f2fs/extent_cache.c
> @@ -71,6 +71,8 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
>  		atomic_set(&et->refcount, 0);
>  		et->count = 0;
>  		atomic_inc(&sbi->total_ext_tree);
> +	} else {
> +		atomic_dec(&sbi->total_zombie_tree);
>  	}
>  	atomic_inc(&et->refcount);
>  	up_write(&sbi->extent_tree_lock);
> @@ -547,10 +549,14 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
>  	unsigned int found;
>  	unsigned int node_cnt = 0, tree_cnt = 0;
>  	int remained;
> +	bool do_free = false;
>  
>  	if (!test_opt(sbi, EXTENT_CACHE))
>  		return 0;
>  
> +	if (!atomic_read(&sbi->total_zombie_tree))
> +		goto free_node;
> +
>  	if (!down_write_trylock(&sbi->extent_tree_lock))
>  		goto out;
>  
> @@ -580,6 +586,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
>  	}
>  	up_write(&sbi->extent_tree_lock);
>  
> +free_node:
>  	/* 2. remove LRU extent entries */
>  	if (!down_write_trylock(&sbi->extent_tree_lock))
>  		goto out;
> @@ -591,9 +598,13 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
>  		if (!remained--)
>  			break;
>  		list_del_init(&en->list);
> +		do_free = true;
>  	}
>  	spin_unlock(&sbi->extent_lock);
>  
> +	if (do_free == false)
> +		goto unlock_out;
> +
>  	/*
>  	 * reset ino for searching victims from beginning of global extent tree.
>  	 */
> @@ -651,6 +662,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
>  
>  	if (inode->i_nlink && !is_bad_inode(inode) && et->count) {
>  		atomic_dec(&et->refcount);
> +		atomic_dec(&sbi->total_zombie_tree);

This will be changed to atomic_inc().
Sorry for confusion.

Thanks,

>  		return;
>  	}
>  
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index a7f6191..90fb970 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -763,6 +763,7 @@ struct f2fs_sb_info {
>  	struct list_head extent_list;		/* lru list for shrinker */
>  	spinlock_t extent_lock;			/* locking extent lru list */
>  	atomic_t total_ext_tree;		/* extent tree count */
> +	atomic_t total_zombie_tree;		/* extent zombie tree count */
>  	atomic_t total_ext_node;		/* extent info count */
>  
>  	/* basic filesystem units */
> diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> index a11e099..93606f2 100644
> --- a/fs/f2fs/shrinker.c
> +++ b/fs/f2fs/shrinker.c
> @@ -32,7 +32,7 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
>  
>  static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
>  {
> -	return atomic_read(&sbi->total_ext_tree) +
> +	return atomic_read(&sbi->total_zombie_tree) +
>  				atomic_read(&sbi->total_ext_node);
>  }
>  
> -- 
> 2.5.4 (Apple Git-61)

RE: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries

[Chao Yu]

Hi Jaegeuk,

We should update &total_zombie_tree whenever removing unreferenced
extent tree during shrinking:
- f2fs_shrink_extent_tree
if (!atomic_read(&et->refcount)) {
	...
	atomic_dec(&sbi->total_ext_tree);
	atomic_dec(&sbi->total_zombie_tree);
	...
}

Other parts look good to me. :)

Reviewed-by: Chao Yu <chao2.yu@samsung.com>

Thanks,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Tuesday, December 22, 2015 11:39 AM
> To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Cc: Jaegeuk Kim
> Subject: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries
> 
> If there is no candidates for shrinking slab entries, we don't need to traverse
> any trees at all.
> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>  fs/f2fs/extent_cache.c | 12 ++++++++++++
>  fs/f2fs/f2fs.h         |  1 +
>  fs/f2fs/shrinker.c     |  2 +-
>  3 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> index 0e97d6af..32693af 100644
> --- a/fs/f2fs/extent_cache.c
> +++ b/fs/f2fs/extent_cache.c
> @@ -71,6 +71,8 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
>  		atomic_set(&et->refcount, 0);
>  		et->count = 0;
>  		atomic_inc(&sbi->total_ext_tree);
> +	} else {
> +		atomic_dec(&sbi->total_zombie_tree);
>  	}
>  	atomic_inc(&et->refcount);
>  	up_write(&sbi->extent_tree_lock);
> @@ -547,10 +549,14 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> nr_shrink)
>  	unsigned int found;
>  	unsigned int node_cnt = 0, tree_cnt = 0;
>  	int remained;
> +	bool do_free = false;
> 
>  	if (!test_opt(sbi, EXTENT_CACHE))
>  		return 0;
> 
> +	if (!atomic_read(&sbi->total_zombie_tree))
> +		goto free_node;
> +
>  	if (!down_write_trylock(&sbi->extent_tree_lock))
>  		goto out;
> 
> @@ -580,6 +586,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> nr_shrink)
>  	}
>  	up_write(&sbi->extent_tree_lock);
> 
> +free_node:
>  	/* 2. remove LRU extent entries */
>  	if (!down_write_trylock(&sbi->extent_tree_lock))
>  		goto out;
> @@ -591,9 +598,13 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> nr_shrink)
>  		if (!remained--)
>  			break;
>  		list_del_init(&en->list);
> +		do_free = true;
>  	}
>  	spin_unlock(&sbi->extent_lock);
> 
> +	if (do_free == false)
> +		goto unlock_out;
> +
>  	/*
>  	 * reset ino for searching victims from beginning of global extent tree.
>  	 */
> @@ -651,6 +662,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
> 
>  	if (inode->i_nlink && !is_bad_inode(inode) && et->count) {
>  		atomic_dec(&et->refcount);
> +		atomic_dec(&sbi->total_zombie_tree);
>  		return;
>  	}
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index a7f6191..90fb970 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -763,6 +763,7 @@ struct f2fs_sb_info {
>  	struct list_head extent_list;		/* lru list for shrinker */
>  	spinlock_t extent_lock;			/* locking extent lru list */
>  	atomic_t total_ext_tree;		/* extent tree count */
> +	atomic_t total_zombie_tree;		/* extent zombie tree count */
>  	atomic_t total_ext_node;		/* extent info count */
> 
>  	/* basic filesystem units */
> diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> index a11e099..93606f2 100644
> --- a/fs/f2fs/shrinker.c
> +++ b/fs/f2fs/shrinker.c
> @@ -32,7 +32,7 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
> 
>  static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
>  {
> -	return atomic_read(&sbi->total_ext_tree) +
> +	return atomic_read(&sbi->total_zombie_tree) +
>  				atomic_read(&sbi->total_ext_node);
>  }
> 
> --
> 2.5.4 (Apple Git-61)
> 
> 
> ------------------------------------------------------------------------------
> _______________________________________________
> Linux-f2fs-devel mailing list
> Linux-f2fs-devel@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

RE: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree

[Chao Yu]

Hi Jaegeuk,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Tuesday, December 22, 2015 11:39 AM
> To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Cc: Jaegeuk Kim
> Subject: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree
> 
> It would be better to use atomic variable for total_extent_tree.

total_extent_tree was protected by extent_tree_lock semaphore, so intention here
is to make related calculation in available_free_memory or update_general_status
more accurate, right?

Thanks,

> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>  fs/f2fs/debug.c        | 5 +++--
>  fs/f2fs/extent_cache.c | 8 ++++----
>  fs/f2fs/f2fs.h         | 2 +-
>  fs/f2fs/node.c         | 3 ++-
>  fs/f2fs/shrinker.c     | 3 ++-
>  5 files changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
> index bb307e6..ed5dfcc 100644
> --- a/fs/f2fs/debug.c
> +++ b/fs/f2fs/debug.c
> @@ -38,7 +38,7 @@ static void update_general_status(struct f2fs_sb_info *sbi)
>  	si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
>  	si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
>  	si->total_ext = atomic64_read(&sbi->total_hit_ext);
> -	si->ext_tree = sbi->total_ext_tree;
> +	si->ext_tree = atomic_read(&sbi->total_ext_tree);
>  	si->ext_node = atomic_read(&sbi->total_ext_node);
>  	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
>  	si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
> @@ -193,7 +193,8 @@ get_cache:
>  	si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
>  	for (i = 0; i <= UPDATE_INO; i++)
>  		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
> -	si->cache_mem += sbi->total_ext_tree * sizeof(struct extent_tree);
> +	si->cache_mem += atomic_read(&sbi->total_ext_tree) *
> +						sizeof(struct extent_tree);
>  	si->cache_mem += atomic_read(&sbi->total_ext_node) *
>  						sizeof(struct extent_node);
> 
> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> index e86e9f1e..0e97d6af 100644
> --- a/fs/f2fs/extent_cache.c
> +++ b/fs/f2fs/extent_cache.c
> @@ -70,7 +70,7 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
>  		rwlock_init(&et->lock);
>  		atomic_set(&et->refcount, 0);
>  		et->count = 0;
> -		sbi->total_ext_tree++;
> +		atomic_inc(&sbi->total_ext_tree);
>  	}
>  	atomic_inc(&et->refcount);
>  	up_write(&sbi->extent_tree_lock);
> @@ -570,7 +570,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> nr_shrink)
> 
>  				radix_tree_delete(root, et->ino);
>  				kmem_cache_free(extent_tree_slab, et);
> -				sbi->total_ext_tree--;
> +				atomic_dec(&sbi->total_ext_tree);
>  				tree_cnt++;
> 
>  				if (node_cnt + tree_cnt >= nr_shrink)
> @@ -663,7 +663,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
>  	f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count);
>  	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
>  	kmem_cache_free(extent_tree_slab, et);
> -	sbi->total_ext_tree--;
> +	atomic_dec(&sbi->total_ext_tree);
>  	up_write(&sbi->extent_tree_lock);
> 
>  	F2FS_I(inode)->extent_tree = NULL;
> @@ -715,7 +715,7 @@ void init_extent_cache_info(struct f2fs_sb_info *sbi)
>  	init_rwsem(&sbi->extent_tree_lock);
>  	INIT_LIST_HEAD(&sbi->extent_list);
>  	spin_lock_init(&sbi->extent_lock);
> -	sbi->total_ext_tree = 0;
> +	atomic_set(&sbi->total_ext_tree, 0);
>  	atomic_set(&sbi->total_ext_node, 0);
>  }
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 19beabe..a7f6191 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -762,7 +762,7 @@ struct f2fs_sb_info {
>  	struct rw_semaphore extent_tree_lock;	/* locking extent radix tree */
>  	struct list_head extent_list;		/* lru list for shrinker */
>  	spinlock_t extent_lock;			/* locking extent lru list */
> -	int total_ext_tree;			/* extent tree count */
> +	atomic_t total_ext_tree;		/* extent tree count */
>  	atomic_t total_ext_node;		/* extent info count */
> 
>  	/* basic filesystem units */
> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> index d842b19..6cc8ac7 100644
> --- a/fs/f2fs/node.c
> +++ b/fs/f2fs/node.c
> @@ -65,7 +65,8 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
>  				sizeof(struct ino_entry)) >> PAGE_CACHE_SHIFT;
>  		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
>  	} else if (type == EXTENT_CACHE) {
> -		mem_size = (sbi->total_ext_tree * sizeof(struct extent_tree) +
> +		mem_size = (atomic_read(&sbi->total_ext_tree) *
> +				sizeof(struct extent_tree) +
>  				atomic_read(&sbi->total_ext_node) *
>  				sizeof(struct extent_node)) >> PAGE_CACHE_SHIFT;
>  		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
> diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> index da0d8e0..a11e099 100644
> --- a/fs/f2fs/shrinker.c
> +++ b/fs/f2fs/shrinker.c
> @@ -32,7 +32,8 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
> 
>  static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
>  {
> -	return sbi->total_ext_tree + atomic_read(&sbi->total_ext_node);
> +	return atomic_read(&sbi->total_ext_tree) +
> +				atomic_read(&sbi->total_ext_node);
>  }
> 
>  unsigned long f2fs_shrink_count(struct shrinker *shrink,
> --
> 2.5.4 (Apple Git-61)
> 
> 
> ------------------------------------------------------------------------------
> _______________________________________________
> Linux-f2fs-devel mailing list
> Linux-f2fs-devel@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

Re: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree

[Jaegeuk Kim]

On Tue, Dec 22, 2015 at 01:28:09PM +0800, Chao Yu wrote:
> Hi Jaegeuk,
> 
> > -----Original Message-----
> > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > Sent: Tuesday, December 22, 2015 11:39 AM
> > To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> > linux-f2fs-devel@lists.sourceforge.net
> > Cc: Jaegeuk Kim
> > Subject: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree
> > 
> > It would be better to use atomic variable for total_extent_tree.
> 
> total_extent_tree was protected by extent_tree_lock semaphore, so intention here
> is to make related calculation in available_free_memory or update_general_status
> more accurate, right?

Moreover, another major thing is to specify it is atomic along with other extent
counts.

Thanks,

> 
> Thanks,
> 
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> > ---
> >  fs/f2fs/debug.c        | 5 +++--
> >  fs/f2fs/extent_cache.c | 8 ++++----
> >  fs/f2fs/f2fs.h         | 2 +-
> >  fs/f2fs/node.c         | 3 ++-
> >  fs/f2fs/shrinker.c     | 3 ++-
> >  5 files changed, 12 insertions(+), 9 deletions(-)
> > 
> > diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
> > index bb307e6..ed5dfcc 100644
> > --- a/fs/f2fs/debug.c
> > +++ b/fs/f2fs/debug.c
> > @@ -38,7 +38,7 @@ static void update_general_status(struct f2fs_sb_info *sbi)
> >  	si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
> >  	si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
> >  	si->total_ext = atomic64_read(&sbi->total_hit_ext);
> > -	si->ext_tree = sbi->total_ext_tree;
> > +	si->ext_tree = atomic_read(&sbi->total_ext_tree);
> >  	si->ext_node = atomic_read(&sbi->total_ext_node);
> >  	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
> >  	si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
> > @@ -193,7 +193,8 @@ get_cache:
> >  	si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
> >  	for (i = 0; i <= UPDATE_INO; i++)
> >  		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
> > -	si->cache_mem += sbi->total_ext_tree * sizeof(struct extent_tree);
> > +	si->cache_mem += atomic_read(&sbi->total_ext_tree) *
> > +						sizeof(struct extent_tree);
> >  	si->cache_mem += atomic_read(&sbi->total_ext_node) *
> >  						sizeof(struct extent_node);
> > 
> > diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> > index e86e9f1e..0e97d6af 100644
> > --- a/fs/f2fs/extent_cache.c
> > +++ b/fs/f2fs/extent_cache.c
> > @@ -70,7 +70,7 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
> >  		rwlock_init(&et->lock);
> >  		atomic_set(&et->refcount, 0);
> >  		et->count = 0;
> > -		sbi->total_ext_tree++;
> > +		atomic_inc(&sbi->total_ext_tree);
> >  	}
> >  	atomic_inc(&et->refcount);
> >  	up_write(&sbi->extent_tree_lock);
> > @@ -570,7 +570,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> > nr_shrink)
> > 
> >  				radix_tree_delete(root, et->ino);
> >  				kmem_cache_free(extent_tree_slab, et);
> > -				sbi->total_ext_tree--;
> > +				atomic_dec(&sbi->total_ext_tree);
> >  				tree_cnt++;
> > 
> >  				if (node_cnt + tree_cnt >= nr_shrink)
> > @@ -663,7 +663,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
> >  	f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count);
> >  	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
> >  	kmem_cache_free(extent_tree_slab, et);
> > -	sbi->total_ext_tree--;
> > +	atomic_dec(&sbi->total_ext_tree);
> >  	up_write(&sbi->extent_tree_lock);
> > 
> >  	F2FS_I(inode)->extent_tree = NULL;
> > @@ -715,7 +715,7 @@ void init_extent_cache_info(struct f2fs_sb_info *sbi)
> >  	init_rwsem(&sbi->extent_tree_lock);
> >  	INIT_LIST_HEAD(&sbi->extent_list);
> >  	spin_lock_init(&sbi->extent_lock);
> > -	sbi->total_ext_tree = 0;
> > +	atomic_set(&sbi->total_ext_tree, 0);
> >  	atomic_set(&sbi->total_ext_node, 0);
> >  }
> > 
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 19beabe..a7f6191 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -762,7 +762,7 @@ struct f2fs_sb_info {
> >  	struct rw_semaphore extent_tree_lock;	/* locking extent radix tree */
> >  	struct list_head extent_list;		/* lru list for shrinker */
> >  	spinlock_t extent_lock;			/* locking extent lru list */
> > -	int total_ext_tree;			/* extent tree count */
> > +	atomic_t total_ext_tree;		/* extent tree count */
> >  	atomic_t total_ext_node;		/* extent info count */
> > 
> >  	/* basic filesystem units */
> > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> > index d842b19..6cc8ac7 100644
> > --- a/fs/f2fs/node.c
> > +++ b/fs/f2fs/node.c
> > @@ -65,7 +65,8 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
> >  				sizeof(struct ino_entry)) >> PAGE_CACHE_SHIFT;
> >  		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
> >  	} else if (type == EXTENT_CACHE) {
> > -		mem_size = (sbi->total_ext_tree * sizeof(struct extent_tree) +
> > +		mem_size = (atomic_read(&sbi->total_ext_tree) *
> > +				sizeof(struct extent_tree) +
> >  				atomic_read(&sbi->total_ext_node) *
> >  				sizeof(struct extent_node)) >> PAGE_CACHE_SHIFT;
> >  		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
> > diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> > index da0d8e0..a11e099 100644
> > --- a/fs/f2fs/shrinker.c
> > +++ b/fs/f2fs/shrinker.c
> > @@ -32,7 +32,8 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
> > 
> >  static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
> >  {
> > -	return sbi->total_ext_tree + atomic_read(&sbi->total_ext_node);
> > +	return atomic_read(&sbi->total_ext_tree) +
> > +				atomic_read(&sbi->total_ext_node);
> >  }
> > 
> >  unsigned long f2fs_shrink_count(struct shrinker *shrink,
> > --
> > 2.5.4 (Apple Git-61)
> > 
> > 
> > ------------------------------------------------------------------------------
> > _______________________________________________
> > Linux-f2fs-devel mailing list
> > Linux-f2fs-devel@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

Re: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries

[Jaegeuk Kim]

On Tue, Dec 22, 2015 at 01:20:13PM +0800, Chao Yu wrote:
> Hi Jaegeuk,
> 
> We should update &total_zombie_tree whenever removing unreferenced
> extent tree during shrinking:
> - f2fs_shrink_extent_tree
> if (!atomic_read(&et->refcount)) {
> 	...
> 	atomic_dec(&sbi->total_ext_tree);
> 	atomic_dec(&sbi->total_zombie_tree);
> 	...

Sure. :)

Thanks,

> }
> 
> Other parts look good to me. :)
> 
> Reviewed-by: Chao Yu <chao2.yu@samsung.com>
> 
> Thanks,
> 
> > -----Original Message-----
> > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > Sent: Tuesday, December 22, 2015 11:39 AM
> > To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> > linux-f2fs-devel@lists.sourceforge.net
> > Cc: Jaegeuk Kim
> > Subject: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries
> > 
> > If there is no candidates for shrinking slab entries, we don't need to traverse
> > any trees at all.
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> > ---
> >  fs/f2fs/extent_cache.c | 12 ++++++++++++
> >  fs/f2fs/f2fs.h         |  1 +
> >  fs/f2fs/shrinker.c     |  2 +-
> >  3 files changed, 14 insertions(+), 1 deletion(-)
> > 
> > diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> > index 0e97d6af..32693af 100644
> > --- a/fs/f2fs/extent_cache.c
> > +++ b/fs/f2fs/extent_cache.c
> > @@ -71,6 +71,8 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
> >  		atomic_set(&et->refcount, 0);
> >  		et->count = 0;
> >  		atomic_inc(&sbi->total_ext_tree);
> > +	} else {
> > +		atomic_dec(&sbi->total_zombie_tree);
> >  	}
> >  	atomic_inc(&et->refcount);
> >  	up_write(&sbi->extent_tree_lock);
> > @@ -547,10 +549,14 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> > nr_shrink)
> >  	unsigned int found;
> >  	unsigned int node_cnt = 0, tree_cnt = 0;
> >  	int remained;
> > +	bool do_free = false;
> > 
> >  	if (!test_opt(sbi, EXTENT_CACHE))
> >  		return 0;
> > 
> > +	if (!atomic_read(&sbi->total_zombie_tree))
> > +		goto free_node;
> > +
> >  	if (!down_write_trylock(&sbi->extent_tree_lock))
> >  		goto out;
> > 
> > @@ -580,6 +586,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> > nr_shrink)
> >  	}
> >  	up_write(&sbi->extent_tree_lock);
> > 
> > +free_node:
> >  	/* 2. remove LRU extent entries */
> >  	if (!down_write_trylock(&sbi->extent_tree_lock))
> >  		goto out;
> > @@ -591,9 +598,13 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> > nr_shrink)
> >  		if (!remained--)
> >  			break;
> >  		list_del_init(&en->list);
> > +		do_free = true;
> >  	}
> >  	spin_unlock(&sbi->extent_lock);
> > 
> > +	if (do_free == false)
> > +		goto unlock_out;
> > +
> >  	/*
> >  	 * reset ino for searching victims from beginning of global extent tree.
> >  	 */
> > @@ -651,6 +662,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
> > 
> >  	if (inode->i_nlink && !is_bad_inode(inode) && et->count) {
> >  		atomic_dec(&et->refcount);
> > +		atomic_dec(&sbi->total_zombie_tree);
> >  		return;
> >  	}
> > 
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index a7f6191..90fb970 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -763,6 +763,7 @@ struct f2fs_sb_info {
> >  	struct list_head extent_list;		/* lru list for shrinker */
> >  	spinlock_t extent_lock;			/* locking extent lru list */
> >  	atomic_t total_ext_tree;		/* extent tree count */
> > +	atomic_t total_zombie_tree;		/* extent zombie tree count */
> >  	atomic_t total_ext_node;		/* extent info count */
> > 
> >  	/* basic filesystem units */
> > diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> > index a11e099..93606f2 100644
> > --- a/fs/f2fs/shrinker.c
> > +++ b/fs/f2fs/shrinker.c
> > @@ -32,7 +32,7 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
> > 
> >  static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
> >  {
> > -	return atomic_read(&sbi->total_ext_tree) +
> > +	return atomic_read(&sbi->total_zombie_tree) +
> >  				atomic_read(&sbi->total_ext_node);
> >  }
> > 
> > --
> > 2.5.4 (Apple Git-61)
> > 
> > 
> > ------------------------------------------------------------------------------
> > _______________________________________________
> > Linux-f2fs-devel mailing list
> > Linux-f2fs-devel@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

RE: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree

[Chao Yu]

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Tuesday, December 22, 2015 3:35 PM
> To: Chao Yu
> Cc: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Subject: Re: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree
> 
> On Tue, Dec 22, 2015 at 01:28:09PM +0800, Chao Yu wrote:
> > Hi Jaegeuk,
> >
> > > -----Original Message-----
> > > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > > Sent: Tuesday, December 22, 2015 11:39 AM
> > > To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> > > linux-f2fs-devel@lists.sourceforge.net
> > > Cc: Jaegeuk Kim
> > > Subject: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree
> > >
> > > It would be better to use atomic variable for total_extent_tree.
> >
> > total_extent_tree was protected by extent_tree_lock semaphore, so intention here
> > is to make related calculation in available_free_memory or update_general_status
> > more accurate, right?
> 
> Moreover, another major thing is to specify it is atomic along with other extent
> counts.

Right, :) Please add:

Reviewed-by: Chao Yu <chao2.yu@samsung.com>

Re: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries

[He YunLei]

On 2015/12/22 13:20, Chao Yu wrote:
> Hi Jaegeuk,
>
> We should update &total_zombie_tree whenever removing unreferenced
> extent tree during shrinking:
> - f2fs_shrink_extent_tree
> if (!atomic_read(&et->refcount)) {
> 	...
> 	atomic_dec(&sbi->total_ext_tree);
> 	atomic_dec(&sbi->total_zombie_tree);
> 	...
> }
>
> Other parts look good to me. :)
>
> Reviewed-by: Chao Yu <chao2.yu@samsung.com>
>
> Thanks,
>
>> -----Original Message-----
>> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
>> Sent: Tuesday, December 22, 2015 11:39 AM
>> To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
>> linux-f2fs-devel@lists.sourceforge.net
>> Cc: Jaegeuk Kim
>> Subject: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries
>>
>> If there is no candidates for shrinking slab entries, we don't need to traverse
>> any trees at all.
>>
>> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
>> ---
>>   fs/f2fs/extent_cache.c | 12 ++++++++++++
>>   fs/f2fs/f2fs.h         |  1 +
>>   fs/f2fs/shrinker.c     |  2 +-
>>   3 files changed, 14 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
>> index 0e97d6af..32693af 100644
>> --- a/fs/f2fs/extent_cache.c
>> +++ b/fs/f2fs/extent_cache.c
>> @@ -71,6 +71,8 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
>>   		atomic_set(&et->refcount, 0);
>>   		et->count = 0;
>>   		atomic_inc(&sbi->total_ext_tree);
>> +	} else {
>> +		atomic_dec(&sbi->total_zombie_tree);
>>   	}
>>   	atomic_inc(&et->refcount);
>>   	up_write(&sbi->extent_tree_lock);
>> @@ -547,10 +549,14 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
>> nr_shrink)
>>   	unsigned int found;
>>   	unsigned int node_cnt = 0, tree_cnt = 0;
>>   	int remained;
>> +	bool do_free = false;
>>
>>   	if (!test_opt(sbi, EXTENT_CACHE))
>>   		return 0;
>>
>> +	if (!atomic_read(&sbi->total_zombie_tree))
>> +		goto free_node;
>> +
>>   	if (!down_write_trylock(&sbi->extent_tree_lock))
>>   		goto out;
>>
>> @@ -580,6 +586,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
>> nr_shrink)
>>   	}
>>   	up_write(&sbi->extent_tree_lock);
>>
>> +free_node:
>>   	/* 2. remove LRU extent entries */
>>   	if (!down_write_trylock(&sbi->extent_tree_lock))
>>   		goto out;
>> @@ -591,9 +598,13 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
>> nr_shrink)
>>   		if (!remained--)
>>   			break;
>>   		list_del_init(&en->list);
>> +		do_free = true;
>>   	}
>>   	spin_unlock(&sbi->extent_lock);
>>
>> +	if (do_free == false)
>> +		goto unlock_out;
>> +
>>   	/*
>>   	 * reset ino for searching victims from beginning of global extent tree.
>>   	 */
>> @@ -651,6 +662,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
>>
>>   	if (inode->i_nlink && !is_bad_inode(inode) && et->count) {
>>   		atomic_dec(&et->refcount);
>> +		atomic_dec(&sbi->total_zombie_tree);
>>   		return;
>>   	}
Hi,all
	here, sbi->total_ext_tree-- also should change to
	atomic_dec(&sbi->total_ext_tree);
Thanks,

>>
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index a7f6191..90fb970 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -763,6 +763,7 @@ struct f2fs_sb_info {
>>   	struct list_head extent_list;		/* lru list for shrinker */
>>   	spinlock_t extent_lock;			/* locking extent lru list */
>>   	atomic_t total_ext_tree;		/* extent tree count */
>> +	atomic_t total_zombie_tree;		/* extent zombie tree count */
>>   	atomic_t total_ext_node;		/* extent info count */
>>
>>   	/* basic filesystem units */
>> diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
>> index a11e099..93606f2 100644
>> --- a/fs/f2fs/shrinker.c
>> +++ b/fs/f2fs/shrinker.c
>> @@ -32,7 +32,7 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
>>
>>   static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
>>   {
>> -	return atomic_read(&sbi->total_ext_tree) +
>> +	return atomic_read(&sbi->total_zombie_tree) +
>>   				atomic_read(&sbi->total_ext_node);
>>   }
>>
>> --
>> 2.5.4 (Apple Git-61)
>>
>>
>> ------------------------------------------------------------------------------
>> _______________________________________________
>> Linux-f2fs-devel mailing list
>> Linux-f2fs-devel@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
>
>
> ------------------------------------------------------------------------------
> _______________________________________________
> Linux-f2fs-devel mailing list
> Linux-f2fs-devel@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
>
> .
>

RE: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries

[Chao Yu]

> -----Original Message-----
> From: He YunLei [mailto:heyunlei@huawei.com]
> Sent: Tuesday, December 22, 2015 8:35 PM
> To: Chao Yu
> Cc: 'Jaegeuk Kim'; linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Subject: Re: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries
> 
> On 2015/12/22 13:20, Chao Yu wrote:
> > Hi Jaegeuk,
> >
> > We should update &total_zombie_tree whenever removing unreferenced
> > extent tree during shrinking:
> > - f2fs_shrink_extent_tree
> > if (!atomic_read(&et->refcount)) {
> > 	...
> > 	atomic_dec(&sbi->total_ext_tree);
> > 	atomic_dec(&sbi->total_zombie_tree);
> > 	...
> > }
> >
> > Other parts look good to me. :)
> >
> > Reviewed-by: Chao Yu <chao2.yu@samsung.com>
> >
> > Thanks,
> >
> >> -----Original Message-----
> >> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> >> Sent: Tuesday, December 22, 2015 11:39 AM
> >> To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> >> linux-f2fs-devel@lists.sourceforge.net
> >> Cc: Jaegeuk Kim
> >> Subject: [f2fs-dev] [PATCH 2/2] f2fs: speed up shrinking extent tree entries
> >>
> >> If there is no candidates for shrinking slab entries, we don't need to traverse
> >> any trees at all.
> >>
> >> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> >> ---
> >>   fs/f2fs/extent_cache.c | 12 ++++++++++++
> >>   fs/f2fs/f2fs.h         |  1 +
> >>   fs/f2fs/shrinker.c     |  2 +-
> >>   3 files changed, 14 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> >> index 0e97d6af..32693af 100644
> >> --- a/fs/f2fs/extent_cache.c
> >> +++ b/fs/f2fs/extent_cache.c
> >> @@ -71,6 +71,8 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
> >>   		atomic_set(&et->refcount, 0);
> >>   		et->count = 0;
> >>   		atomic_inc(&sbi->total_ext_tree);
> >> +	} else {
> >> +		atomic_dec(&sbi->total_zombie_tree);
> >>   	}
> >>   	atomic_inc(&et->refcount);
> >>   	up_write(&sbi->extent_tree_lock);
> >> @@ -547,10 +549,14 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> >> nr_shrink)
> >>   	unsigned int found;
> >>   	unsigned int node_cnt = 0, tree_cnt = 0;
> >>   	int remained;
> >> +	bool do_free = false;
> >>
> >>   	if (!test_opt(sbi, EXTENT_CACHE))
> >>   		return 0;
> >>
> >> +	if (!atomic_read(&sbi->total_zombie_tree))
> >> +		goto free_node;
> >> +
> >>   	if (!down_write_trylock(&sbi->extent_tree_lock))
> >>   		goto out;
> >>
> >> @@ -580,6 +586,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> >> nr_shrink)
> >>   	}
> >>   	up_write(&sbi->extent_tree_lock);
> >>
> >> +free_node:
> >>   	/* 2. remove LRU extent entries */
> >>   	if (!down_write_trylock(&sbi->extent_tree_lock))
> >>   		goto out;
> >> @@ -591,9 +598,13 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> >> nr_shrink)
> >>   		if (!remained--)
> >>   			break;
> >>   		list_del_init(&en->list);
> >> +		do_free = true;
> >>   	}
> >>   	spin_unlock(&sbi->extent_lock);
> >>
> >> +	if (do_free == false)
> >> +		goto unlock_out;
> >> +
> >>   	/*
> >>   	 * reset ino for searching victims from beginning of global extent tree.
> >>   	 */
> >> @@ -651,6 +662,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
> >>
> >>   	if (inode->i_nlink && !is_bad_inode(inode) && et->count) {
> >>   		atomic_dec(&et->refcount);
> >> +		atomic_dec(&sbi->total_zombie_tree);
> >>   		return;
> >>   	}
> Hi,all
> 	here, sbi->total_ext_tree-- also should change to
> 	atomic_dec(&sbi->total_ext_tree);

Yunlei,

Seems not right.

Thanks,

> Thanks,
> 
> >>
> >> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> >> index a7f6191..90fb970 100644
> >> --- a/fs/f2fs/f2fs.h
> >> +++ b/fs/f2fs/f2fs.h
> >> @@ -763,6 +763,7 @@ struct f2fs_sb_info {
> >>   	struct list_head extent_list;		/* lru list for shrinker */
> >>   	spinlock_t extent_lock;			/* locking extent lru list */
> >>   	atomic_t total_ext_tree;		/* extent tree count */
> >> +	atomic_t total_zombie_tree;		/* extent zombie tree count */
> >>   	atomic_t total_ext_node;		/* extent info count */
> >>
> >>   	/* basic filesystem units */
> >> diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> >> index a11e099..93606f2 100644
> >> --- a/fs/f2fs/shrinker.c
> >> +++ b/fs/f2fs/shrinker.c
> >> @@ -32,7 +32,7 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
> >>
> >>   static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
> >>   {
> >> -	return atomic_read(&sbi->total_ext_tree) +
> >> +	return atomic_read(&sbi->total_zombie_tree) +
> >>   				atomic_read(&sbi->total_ext_node);
> >>   }
> >>
> >> --
> >> 2.5.4 (Apple Git-61)
> >>
> >>
> >> ------------------------------------------------------------------------------
> >> _______________________________________________
> >> Linux-f2fs-devel mailing list
> >> Linux-f2fs-devel@lists.sourceforge.net
> >> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
> >
> >
> > ------------------------------------------------------------------------------
> > _______________________________________________
> > Linux-f2fs-devel mailing list
> > Linux-f2fs-devel@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
> >
> > .
> >

Re: [PATCH 1/2] f2fs: use atomic variable for total_extent_tree

[He YunLei]

On 2015/12/22 11:38, Jaegeuk Kim wrote:
> It would be better to use atomic variable for total_extent_tree.
>
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>   fs/f2fs/debug.c        | 5 +++--
>   fs/f2fs/extent_cache.c | 8 ++++----
>   fs/f2fs/f2fs.h         | 2 +-
>   fs/f2fs/node.c         | 3 ++-
>   fs/f2fs/shrinker.c     | 3 ++-
>   5 files changed, 12 insertions(+), 9 deletions(-)
>
> diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
> index bb307e6..ed5dfcc 100644
> --- a/fs/f2fs/debug.c
> +++ b/fs/f2fs/debug.c
> @@ -38,7 +38,7 @@ static void update_general_status(struct f2fs_sb_info *sbi)
>   	si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
>   	si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
>   	si->total_ext = atomic64_read(&sbi->total_hit_ext);
> -	si->ext_tree = sbi->total_ext_tree;
> +	si->ext_tree = atomic_read(&sbi->total_ext_tree);
>   	si->ext_node = atomic_read(&sbi->total_ext_node);
>   	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
>   	si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
> @@ -193,7 +193,8 @@ get_cache:
>   	si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
>   	for (i = 0; i <= UPDATE_INO; i++)
>   		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
> -	si->cache_mem += sbi->total_ext_tree * sizeof(struct extent_tree);
> +	si->cache_mem += atomic_read(&sbi->total_ext_tree) *
> +						sizeof(struct extent_tree);
>   	si->cache_mem += atomic_read(&sbi->total_ext_node) *
>   						sizeof(struct extent_node);
>
> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> index e86e9f1e..0e97d6af 100644
> --- a/fs/f2fs/extent_cache.c
> +++ b/fs/f2fs/extent_cache.c
> @@ -70,7 +70,7 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
>   		rwlock_init(&et->lock);
>   		atomic_set(&et->refcount, 0);
>   		et->count = 0;
> -		sbi->total_ext_tree++;
> +		atomic_inc(&sbi->total_ext_tree);
>   	}
>   	atomic_inc(&et->refcount);
>   	up_write(&sbi->extent_tree_lock);
> @@ -570,7 +570,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
>
>   				radix_tree_delete(root, et->ino);
>   				kmem_cache_free(extent_tree_slab, et);
> -				sbi->total_ext_tree--;
> +				atomic_dec(&sbi->total_ext_tree);
>   				tree_cnt++;
>
>   				if (node_cnt + tree_cnt >= nr_shrink)
> @@ -663,7 +663,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
>   	f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count);
>   	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
>   	kmem_cache_free(extent_tree_slab, et);
> -	sbi->total_ext_tree--;
> +	atomic_dec(&sbi->total_ext_tree);
>   	up_write(&sbi->extent_tree_lock);
>
>   	F2FS_I(inode)->extent_tree = NULL;
> @@ -715,7 +715,7 @@ void init_extent_cache_info(struct f2fs_sb_info *sbi)
>   	init_rwsem(&sbi->extent_tree_lock);
>   	INIT_LIST_HEAD(&sbi->extent_list);
>   	spin_lock_init(&sbi->extent_lock);
> -	sbi->total_ext_tree = 0;
> +	atomic_set(&sbi->total_ext_tree, 0);
Hi,
	here we'd better to init total_zombie_tree:
	atomic_set(&sbi->total_zombie_tree, 0);
Thanks,
>   	atomic_set(&sbi->total_ext_node, 0);
>   }
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 19beabe..a7f6191 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -762,7 +762,7 @@ struct f2fs_sb_info {
>   	struct rw_semaphore extent_tree_lock;	/* locking extent radix tree */
>   	struct list_head extent_list;		/* lru list for shrinker */
>   	spinlock_t extent_lock;			/* locking extent lru list */
> -	int total_ext_tree;			/* extent tree count */
> +	atomic_t total_ext_tree;		/* extent tree count */
>   	atomic_t total_ext_node;		/* extent info count */
>
>   	/* basic filesystem units */
> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> index d842b19..6cc8ac7 100644
> --- a/fs/f2fs/node.c
> +++ b/fs/f2fs/node.c
> @@ -65,7 +65,8 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
>   				sizeof(struct ino_entry)) >> PAGE_CACHE_SHIFT;
>   		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
>   	} else if (type == EXTENT_CACHE) {
> -		mem_size = (sbi->total_ext_tree * sizeof(struct extent_tree) +
> +		mem_size = (atomic_read(&sbi->total_ext_tree) *
> +				sizeof(struct extent_tree) +
>   				atomic_read(&sbi->total_ext_node) *
>   				sizeof(struct extent_node)) >> PAGE_CACHE_SHIFT;
>   		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
> diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> index da0d8e0..a11e099 100644
> --- a/fs/f2fs/shrinker.c
> +++ b/fs/f2fs/shrinker.c
> @@ -32,7 +32,8 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
>
>   static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
>   {
> -	return sbi->total_ext_tree + atomic_read(&sbi->total_ext_node);
> +	return atomic_read(&sbi->total_ext_tree) +
> +				atomic_read(&sbi->total_ext_node);
>   }
>
>   unsigned long f2fs_shrink_count(struct shrinker *shrink,
>


------------------------------------------------------------------------------

RE: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree

[Chao Yu]

Hi Yunlei,

Thanks for your report, but the fix should be done in another patch. :)

Hi Jaegeuk,

We should add to init total_zombie_tree in ("f2fs: speed up shrinking
extent tree entries") as Yunlei reported.

Thanks,

> -----Original Message-----
> From: He YunLei [mailto:heyunlei@huawei.com]
> Sent: Tuesday, December 29, 2015 7:11 PM
> To: Jaegeuk Kim
> Cc: linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Subject: Re: [f2fs-dev] [PATCH 1/2] f2fs: use atomic variable for total_extent_tree
> 
> On 2015/12/22 11:38, Jaegeuk Kim wrote:
> > It would be better to use atomic variable for total_extent_tree.
> >
> > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> > ---
> >   fs/f2fs/debug.c        | 5 +++--
> >   fs/f2fs/extent_cache.c | 8 ++++----
> >   fs/f2fs/f2fs.h         | 2 +-
> >   fs/f2fs/node.c         | 3 ++-
> >   fs/f2fs/shrinker.c     | 3 ++-
> >   5 files changed, 12 insertions(+), 9 deletions(-)
> >
> > diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
> > index bb307e6..ed5dfcc 100644
> > --- a/fs/f2fs/debug.c
> > +++ b/fs/f2fs/debug.c
> > @@ -38,7 +38,7 @@ static void update_general_status(struct f2fs_sb_info *sbi)
> >   	si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
> >   	si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
> >   	si->total_ext = atomic64_read(&sbi->total_hit_ext);
> > -	si->ext_tree = sbi->total_ext_tree;
> > +	si->ext_tree = atomic_read(&sbi->total_ext_tree);
> >   	si->ext_node = atomic_read(&sbi->total_ext_node);
> >   	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
> >   	si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
> > @@ -193,7 +193,8 @@ get_cache:
> >   	si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
> >   	for (i = 0; i <= UPDATE_INO; i++)
> >   		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
> > -	si->cache_mem += sbi->total_ext_tree * sizeof(struct extent_tree);
> > +	si->cache_mem += atomic_read(&sbi->total_ext_tree) *
> > +						sizeof(struct extent_tree);
> >   	si->cache_mem += atomic_read(&sbi->total_ext_node) *
> >   						sizeof(struct extent_node);
> >
> > diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> > index e86e9f1e..0e97d6af 100644
> > --- a/fs/f2fs/extent_cache.c
> > +++ b/fs/f2fs/extent_cache.c
> > @@ -70,7 +70,7 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode)
> >   		rwlock_init(&et->lock);
> >   		atomic_set(&et->refcount, 0);
> >   		et->count = 0;
> > -		sbi->total_ext_tree++;
> > +		atomic_inc(&sbi->total_ext_tree);
> >   	}
> >   	atomic_inc(&et->refcount);
> >   	up_write(&sbi->extent_tree_lock);
> > @@ -570,7 +570,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int
> nr_shrink)
> >
> >   				radix_tree_delete(root, et->ino);
> >   				kmem_cache_free(extent_tree_slab, et);
> > -				sbi->total_ext_tree--;
> > +				atomic_dec(&sbi->total_ext_tree);
> >   				tree_cnt++;
> >
> >   				if (node_cnt + tree_cnt >= nr_shrink)
> > @@ -663,7 +663,7 @@ void f2fs_destroy_extent_tree(struct inode *inode)
> >   	f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count);
> >   	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
> >   	kmem_cache_free(extent_tree_slab, et);
> > -	sbi->total_ext_tree--;
> > +	atomic_dec(&sbi->total_ext_tree);
> >   	up_write(&sbi->extent_tree_lock);
> >
> >   	F2FS_I(inode)->extent_tree = NULL;
> > @@ -715,7 +715,7 @@ void init_extent_cache_info(struct f2fs_sb_info *sbi)
> >   	init_rwsem(&sbi->extent_tree_lock);
> >   	INIT_LIST_HEAD(&sbi->extent_list);
> >   	spin_lock_init(&sbi->extent_lock);
> > -	sbi->total_ext_tree = 0;
> > +	atomic_set(&sbi->total_ext_tree, 0);
> Hi,
> 	here we'd better to init total_zombie_tree:
> 	atomic_set(&sbi->total_zombie_tree, 0);
> Thanks,
> >   	atomic_set(&sbi->total_ext_node, 0);
> >   }
> >
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 19beabe..a7f6191 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -762,7 +762,7 @@ struct f2fs_sb_info {
> >   	struct rw_semaphore extent_tree_lock;	/* locking extent radix tree */
> >   	struct list_head extent_list;		/* lru list for shrinker */
> >   	spinlock_t extent_lock;			/* locking extent lru list */
> > -	int total_ext_tree;			/* extent tree count */
> > +	atomic_t total_ext_tree;		/* extent tree count */
> >   	atomic_t total_ext_node;		/* extent info count */
> >
> >   	/* basic filesystem units */
> > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> > index d842b19..6cc8ac7 100644
> > --- a/fs/f2fs/node.c
> > +++ b/fs/f2fs/node.c
> > @@ -65,7 +65,8 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
> >   				sizeof(struct ino_entry)) >> PAGE_CACHE_SHIFT;
> >   		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
> >   	} else if (type == EXTENT_CACHE) {
> > -		mem_size = (sbi->total_ext_tree * sizeof(struct extent_tree) +
> > +		mem_size = (atomic_read(&sbi->total_ext_tree) *
> > +				sizeof(struct extent_tree) +
> >   				atomic_read(&sbi->total_ext_node) *
> >   				sizeof(struct extent_node)) >> PAGE_CACHE_SHIFT;
> >   		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
> > diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> > index da0d8e0..a11e099 100644
> > --- a/fs/f2fs/shrinker.c
> > +++ b/fs/f2fs/shrinker.c
> > @@ -32,7 +32,8 @@ static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
> >
> >   static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
> >   {
> > -	return sbi->total_ext_tree + atomic_read(&sbi->total_ext_node);
> > +	return atomic_read(&sbi->total_ext_tree) +
> > +				atomic_read(&sbi->total_ext_node);
> >   }
> >
> >   unsigned long f2fs_shrink_count(struct shrinker *shrink,
> >
> 
> 
> ------------------------------------------------------------------------------
> _______________________________________________
> Linux-f2fs-devel mailing list
> Linux-f2fs-devel@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel