Commit a95ba66a authored by Jaegeuk Kim's avatar Jaegeuk Kim
Browse files

f2fs: avoid race condition for shrinker count 



Light reported sometimes shinker gets nat_cnt < dirty_nat_cnt resulting in
wrong do_shinker work. Let's avoid to return insane overflowed value by adding
single tracking value.

Reported-by: default avatarLight Hsieh <Light.Hsieh@mediatek.com>
Reviewed-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 5fdb322f

fs/f2fs/checkpoint.c

+1 −1
Original line number Diff line number Diff line
@@ -1619,7 +1619,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) 
			goto out;

		}



		if (NM_I(sbi)->dirty_nat_cnt == 0 &&

		if (NM_I(sbi)->nat_cnt[DIRTY_NAT] == 0 &&

				SIT_I(sbi)->dirty_sentries == 0 &&

				prefree_segments(sbi) == 0) {

			f2fs_flush_sit_entries(sbi, cpc);

fs/f2fs/debug.c

+6 −5
Original line number Diff line number Diff line
@@ -145,8 +145,8 @@ static void update_general_status(struct f2fs_sb_info *sbi) 
		si->node_pages = NODE_MAPPING(sbi)->nrpages;

	if (sbi->meta_inode)

		si->meta_pages = META_MAPPING(sbi)->nrpages;

	si->nats = NM_I(sbi)->nat_cnt;

	si->dirty_nats = NM_I(sbi)->dirty_nat_cnt;

	si->nats = NM_I(sbi)->nat_cnt[TOTAL_NAT];

	si->dirty_nats = NM_I(sbi)->nat_cnt[DIRTY_NAT];

	si->sits = MAIN_SEGS(sbi);

	si->dirty_sits = SIT_I(sbi)->dirty_sentries;

	si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID];
@@ -278,8 +278,9 @@ static void update_mem_info(struct f2fs_sb_info *sbi) 
	si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID] +

				NM_I(sbi)->nid_cnt[PREALLOC_NID]) *

				sizeof(struct free_nid);

	si->cache_mem += NM_I(sbi)->nat_cnt * sizeof(struct nat_entry);

	si->cache_mem += NM_I(sbi)->dirty_nat_cnt *

	si->cache_mem += NM_I(sbi)->nat_cnt[TOTAL_NAT] *

				sizeof(struct nat_entry);

	si->cache_mem += NM_I(sbi)->nat_cnt[DIRTY_NAT] *

				sizeof(struct nat_entry_set);

	si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);

	for (i = 0; i < MAX_INO_ENTRY; i++)

fs/f2fs/f2fs.h

+8 −2
Original line number Diff line number Diff line
@@ -820,6 +820,13 @@ enum nid_state { 
	MAX_NID_STATE,

};



enum nat_state {

	TOTAL_NAT,

	DIRTY_NAT,

	RECLAIMABLE_NAT,

	MAX_NAT_STATE,

};



struct f2fs_nm_info {

	block_t nat_blkaddr;		/* base disk address of NAT */

	nid_t max_nid;			/* maximum possible node ids */
@@ -835,8 +842,7 @@ struct f2fs_nm_info { 
	struct rw_semaphore nat_tree_lock;	/* protect nat_tree_lock */

	struct list_head nat_entries;	/* cached nat entry list (clean) */

	spinlock_t nat_list_lock;	/* protect clean nat entry list */

	unsigned int nat_cnt;		/* the # of cached nat entries */

	unsigned int dirty_nat_cnt;	/* total num of nat entries in set */

	unsigned int nat_cnt[MAX_NAT_STATE]; /* the # of cached nat entries */

	unsigned int nat_blocks;	/* # of nat blocks */



	/* free node ids management */

fs/f2fs/node.c

+18 −11
Original line number Diff line number Diff line
@@ -62,8 +62,8 @@ bool f2fs_available_free_memory(struct f2fs_sb_info *sbi, int type) 
				sizeof(struct free_nid)) >> PAGE_SHIFT;

		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 2);

	} else if (type == NAT_ENTRIES) {

		mem_size = (nm_i->nat_cnt * sizeof(struct nat_entry)) >>

							PAGE_SHIFT;

		mem_size = (nm_i->nat_cnt[TOTAL_NAT] *

				sizeof(struct nat_entry)) >> PAGE_SHIFT;

		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 2);

		if (excess_cached_nats(sbi))

			res = false;
@@ -177,7 +177,8 @@ static struct nat_entry *__init_nat_entry(struct f2fs_nm_info *nm_i, 
	list_add_tail(&ne->list, &nm_i->nat_entries);

	spin_unlock(&nm_i->nat_list_lock);



	nm_i->nat_cnt++;

	nm_i->nat_cnt[TOTAL_NAT]++;

	nm_i->nat_cnt[RECLAIMABLE_NAT]++;

	return ne;

}
@@ -207,7 +208,8 @@ static unsigned int __gang_lookup_nat_cache(struct f2fs_nm_info *nm_i, 
static void __del_from_nat_cache(struct f2fs_nm_info *nm_i, struct nat_entry *e)

{

	radix_tree_delete(&nm_i->nat_root, nat_get_nid(e));

	nm_i->nat_cnt--;

	nm_i->nat_cnt[TOTAL_NAT]--;

	nm_i->nat_cnt[RECLAIMABLE_NAT]--;

	__free_nat_entry(e);

}
@@ -253,7 +255,8 @@ static void __set_nat_cache_dirty(struct f2fs_nm_info *nm_i, 
	if (get_nat_flag(ne, IS_DIRTY))

		goto refresh_list;



	nm_i->dirty_nat_cnt++;

	nm_i->nat_cnt[DIRTY_NAT]++;

	nm_i->nat_cnt[RECLAIMABLE_NAT]--;

	set_nat_flag(ne, IS_DIRTY, true);

refresh_list:

	spin_lock(&nm_i->nat_list_lock);
@@ -273,7 +276,8 @@ static void __clear_nat_cache_dirty(struct f2fs_nm_info *nm_i, 


	set_nat_flag(ne, IS_DIRTY, false);

	set->entry_cnt--;

	nm_i->dirty_nat_cnt--;

	nm_i->nat_cnt[DIRTY_NAT]--;

	nm_i->nat_cnt[RECLAIMABLE_NAT]++;

}



static unsigned int __gang_lookup_nat_set(struct f2fs_nm_info *nm_i,
@@ -2944,14 +2948,17 @@ int f2fs_flush_nat_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc) 
	LIST_HEAD(sets);

	int err = 0;



	/* during unmount, let's flush nat_bits before checking dirty_nat_cnt */

	/*

	 * during unmount, let's flush nat_bits before checking

	 * nat_cnt[DIRTY_NAT].

	 */

	if (enabled_nat_bits(sbi, cpc)) {

		down_write(&nm_i->nat_tree_lock);

		remove_nats_in_journal(sbi);

		up_write(&nm_i->nat_tree_lock);

	}



	if (!nm_i->dirty_nat_cnt)

	if (!nm_i->nat_cnt[DIRTY_NAT])

		return 0;



	down_write(&nm_i->nat_tree_lock);
@@ -2962,7 +2969,8 @@ int f2fs_flush_nat_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc) 
	 * into nat entry set.

	 */

	if (enabled_nat_bits(sbi, cpc) ||

		!__has_cursum_space(journal, nm_i->dirty_nat_cnt, NAT_JOURNAL))

		!__has_cursum_space(journal,

			nm_i->nat_cnt[DIRTY_NAT], NAT_JOURNAL))

		remove_nats_in_journal(sbi);



	while ((found = __gang_lookup_nat_set(nm_i,
@@ -3086,7 +3094,6 @@ static int init_node_manager(struct f2fs_sb_info *sbi) 
						F2FS_RESERVED_NODE_NUM;

	nm_i->nid_cnt[FREE_NID] = 0;

	nm_i->nid_cnt[PREALLOC_NID] = 0;

	nm_i->nat_cnt = 0;

	nm_i->ram_thresh = DEF_RAM_THRESHOLD;

	nm_i->ra_nid_pages = DEF_RA_NID_PAGES;

	nm_i->dirty_nats_ratio = DEF_DIRTY_NAT_RATIO_THRESHOLD;
@@ -3220,7 +3227,7 @@ void f2fs_destroy_node_manager(struct f2fs_sb_info *sbi) 
			__del_from_nat_cache(nm_i, natvec[idx]);

		}

	}

	f2fs_bug_on(sbi, nm_i->nat_cnt);

	f2fs_bug_on(sbi, nm_i->nat_cnt[TOTAL_NAT]);



	/* destroy nat set cache */

	nid = 0;

fs/f2fs/node.h

+2 −2
Original line number Diff line number Diff line
@@ -126,13 +126,13 @@ static inline void raw_nat_from_node_info(struct f2fs_nat_entry *raw_ne, 


static inline bool excess_dirty_nats(struct f2fs_sb_info *sbi)

{

	return NM_I(sbi)->dirty_nat_cnt >= NM_I(sbi)->max_nid *

	return NM_I(sbi)->nat_cnt[DIRTY_NAT] >= NM_I(sbi)->max_nid *

					NM_I(sbi)->dirty_nats_ratio / 100;

}



static inline bool excess_cached_nats(struct f2fs_sb_info *sbi)

{

	return NM_I(sbi)->nat_cnt >= DEF_NAT_CACHE_THRESHOLD;

	return NM_I(sbi)->nat_cnt[TOTAL_NAT] >= DEF_NAT_CACHE_THRESHOLD;

}



static inline bool excess_dirty_nodes(struct f2fs_sb_info *sbi)