Commit 8a7ed66a authored by Jaegeuk Kim's avatar Jaegeuk Kim
Browse files

f2fs: introduce a radix_tree for the free_nid list 



This patch introduces a radix tree for the list of free_nids, which enhances
the performance on free nid management.

Signed-off-by: default avatarJaegeuk Kim <jaegeuk.kim@samsung.com>
parent f978f5a0

fs/f2fs/f2fs.h

+1 −0
Original line number Diff line number Diff line
@@ -247,6 +247,7 @@ struct f2fs_nm_info { 
	struct list_head dirty_nat_entries; /* cached nat entry list (dirty) */



	/* free node ids management */

	struct radix_tree_root free_nid_root;/* root of the free_nid cache */

	struct list_head free_nid_list;	/* a list for free nids */

	spinlock_t free_nid_list_lock;	/* protect free nid list */

	unsigned int fcnt;		/* the number of free node id */

fs/f2fs/node.c

+17 −19
Original line number Diff line number Diff line
@@ -1269,21 +1269,17 @@ const struct address_space_operations f2fs_node_aops = { 
	.releasepage	= f2fs_release_node_page,

};



static struct free_nid *__lookup_free_nid_list(nid_t n, struct list_head *head)

static struct free_nid *__lookup_free_nid_list(struct f2fs_nm_info *nm_i,

						nid_t n)

{

	struct list_head *this;

	struct free_nid *i;

	list_for_each(this, head) {

		i = list_entry(this, struct free_nid, list);

		if (i->nid == n)

			return i;

	}

	return NULL;

	return radix_tree_lookup(&nm_i->free_nid_root, n);

}



static void __del_from_free_nid_list(struct free_nid *i)

static void __del_from_free_nid_list(struct f2fs_nm_info *nm_i,

						struct free_nid *i)

{

	list_del(&i->list);

	radix_tree_delete(&nm_i->free_nid_root, i->nid);

	kmem_cache_free(free_nid_slab, i);

}
@@ -1304,7 +1300,8 @@ static int add_free_nid(struct f2fs_nm_info *nm_i, nid_t nid, bool build) 
		/* do not add allocated nids */

		read_lock(&nm_i->nat_tree_lock);

		ne = __lookup_nat_cache(nm_i, nid);

		if (ne && nat_get_blkaddr(ne) != NULL_ADDR)

		if (ne &&

			(!ne->checkpointed || nat_get_blkaddr(ne) != NULL_ADDR))

			allocated = true;

		read_unlock(&nm_i->nat_tree_lock);

		if (allocated)
@@ -1316,7 +1313,7 @@ static int add_free_nid(struct f2fs_nm_info *nm_i, nid_t nid, bool build) 
	i->state = NID_NEW;



	spin_lock(&nm_i->free_nid_list_lock);

	if (__lookup_free_nid_list(nid, &nm_i->free_nid_list)) {

	if (radix_tree_insert(&nm_i->free_nid_root, i->nid, i)) {

		spin_unlock(&nm_i->free_nid_list_lock);

		kmem_cache_free(free_nid_slab, i);

		return 0;
@@ -1331,9 +1328,9 @@ static void remove_free_nid(struct f2fs_nm_info *nm_i, nid_t nid) 
{

	struct free_nid *i;

	spin_lock(&nm_i->free_nid_list_lock);

	i = __lookup_free_nid_list(nid, &nm_i->free_nid_list);

	i = __lookup_free_nid_list(nm_i, nid);

	if (i && i->state == NID_NEW) {

		__del_from_free_nid_list(i);

		__del_from_free_nid_list(nm_i, i);

		nm_i->fcnt--;

	}

	spin_unlock(&nm_i->free_nid_list_lock);
@@ -1457,9 +1454,9 @@ void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid) 
	struct free_nid *i;



	spin_lock(&nm_i->free_nid_list_lock);

	i = __lookup_free_nid_list(nid, &nm_i->free_nid_list);

	i = __lookup_free_nid_list(nm_i, nid);

	f2fs_bug_on(!i || i->state != NID_ALLOC);

	__del_from_free_nid_list(i);

	__del_from_free_nid_list(nm_i, i);

	spin_unlock(&nm_i->free_nid_list_lock);

}
@@ -1475,10 +1472,10 @@ void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t nid) 
		return;



	spin_lock(&nm_i->free_nid_list_lock);

	i = __lookup_free_nid_list(nid, &nm_i->free_nid_list);

	i = __lookup_free_nid_list(nm_i, nid);

	f2fs_bug_on(!i || i->state != NID_ALLOC);

	if (nm_i->fcnt > 2 * MAX_FREE_NIDS) {

		__del_from_free_nid_list(i);

		__del_from_free_nid_list(nm_i, i);

	} else {

		i->state = NID_NEW;

		nm_i->fcnt++;
@@ -1812,6 +1809,7 @@ static int init_node_manager(struct f2fs_sb_info *sbi) 
	nm_i->fcnt = 0;

	nm_i->nat_cnt = 0;



	INIT_RADIX_TREE(&nm_i->free_nid_root, GFP_ATOMIC);

	INIT_LIST_HEAD(&nm_i->free_nid_list);

	INIT_RADIX_TREE(&nm_i->nat_root, GFP_ATOMIC);

	INIT_LIST_HEAD(&nm_i->nat_entries);
@@ -1865,7 +1863,7 @@ void destroy_node_manager(struct f2fs_sb_info *sbi) 
	spin_lock(&nm_i->free_nid_list_lock);

	list_for_each_entry_safe(i, next_i, &nm_i->free_nid_list, list) {

		f2fs_bug_on(i->state == NID_ALLOC);

		__del_from_free_nid_list(i);

		__del_from_free_nid_list(nm_i, i);

		nm_i->fcnt--;

	}

	f2fs_bug_on(nm_i->fcnt);