Commit a03f01f2 authored by Hou Pengyang's avatar Hou Pengyang Committed by Jaegeuk Kim
Browse files

f2fs: reconstruct the code to free an extent_node 



There are three steps to free an extent node:
1) list_del_init, 2)__detach_extent_node, 3) kmem_cache_free

In path f2fs_destroy_extent_tree, 1->2->3 to free a node,
But in path f2fs_update_extent_tree_range, it is 2->1->3.

This patch makes all the order to be: 1->2->3
It makes sense, since in the next patch, we import a victim list in the
path shrink_extent_tree, we could check if the extent_node is in the victim
list by checking the list_empty(). So it is necessary to put 1) first.

Signed-off-by: default avatarHou Pengyang <houpengyang@huawei.com>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 7c506896

fs/f2fs/extent_cache.c

+25 −30
Original line number Diff line number Diff line
@@ -50,6 +50,24 @@ static void __detach_extent_node(struct f2fs_sb_info *sbi, 


	if (et->cached_en == en)

		et->cached_en = NULL;

	kmem_cache_free(extent_node_slab, en);

}



/*

 * Flow to release an extent_node:

 * 1. list_del_init

 * 2. __detach_extent_node

 * 3. kmem_cache_free.

 */

static void __release_extent_node(struct f2fs_sb_info *sbi,

			struct extent_tree *et, struct extent_node *en)

{

	spin_lock(&sbi->extent_lock);

	if (!list_empty(&en->list))

		list_del_init(&en->list);

	spin_unlock(&sbi->extent_lock);



	__detach_extent_node(sbi, et, en);

}



static struct extent_tree *__grab_extent_tree(struct inode *inode)
@@ -140,17 +158,10 @@ static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi, 
		next = rb_next(node);

		en = rb_entry(node, struct extent_node, rb_node);



		if (free_all) {

			spin_lock(&sbi->extent_lock);

			if (!list_empty(&en->list))

				list_del_init(&en->list);

			spin_unlock(&sbi->extent_lock);

		}



		if (free_all || list_empty(&en->list)) {

		if (free_all)

			__release_extent_node(sbi, et, en);

		else if (list_empty(&en->list))

			__detach_extent_node(sbi, et, en);

			kmem_cache_free(extent_node_slab, en);

		}

		node = next;

	}
@@ -329,7 +340,6 @@ lookup_neighbors: 


static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi,

				struct extent_tree *et, struct extent_info *ei,

				struct extent_node **den,

				struct extent_node *prev_ex,

				struct extent_node *next_ex)

{
@@ -342,10 +352,8 @@ static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi, 
	}



	if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) {

		if (en) {

			__detach_extent_node(sbi, et, prev_ex);

			*den = prev_ex;

		}

		if (en)

			__release_extent_node(sbi, et, prev_ex);

		next_ex->ei.fofs = ei->fofs;

		next_ex->ei.blk = ei->blk;

		next_ex->ei.len += ei->len;
@@ -479,7 +487,7 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode, 
		if (parts)

			__try_update_largest_extent(et, en);

		else

			__detach_extent_node(sbi, et, en);

			__release_extent_node(sbi, et, en);



		/*

		 * if original extent is split into zero or two parts, extent
@@ -493,26 +501,18 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode, 


		/* update in global extent list */

		spin_lock(&sbi->extent_lock);

		if (!parts && !list_empty(&en->list))

			list_del(&en->list);

		if (en1)

			list_add_tail(&en1->list, &sbi->extent_list);

		spin_unlock(&sbi->extent_lock);



		/* release extent node */

		if (!parts)

			kmem_cache_free(extent_node_slab, en);



		en = next_en;

	}



	/* 3. update extent in extent cache */

	if (blkaddr) {

		struct extent_node *den = NULL;



		set_extent_info(&ei, fofs, blkaddr, len);

		en1 = __try_merge_extent_node(sbi, et, &ei, &den,

							prev_en, next_en);

		en1 = __try_merge_extent_node(sbi, et, &ei, prev_en, next_en);

		if (!en1)

			en1 = __insert_extent_tree(sbi, et, &ei,

						insert_p, insert_parent);
@@ -532,12 +532,7 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode, 
			else

				list_move_tail(&en1->list, &sbi->extent_list);

		}

		if (den && !list_empty(&den->list))

			list_del(&den->list);

		spin_unlock(&sbi->extent_lock);



		if (den)

			kmem_cache_free(extent_node_slab, den);

	}



	if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT))

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