Commits
Chao Yu committed 04d47e67386
f2fs: fix to account total free nid correctly
Thread A Thread B Thread C
- f2fs_create
- f2fs_new_inode
- f2fs_lock_op
- alloc_nid
alloc last nid
- f2fs_unlock_op
- f2fs_create
- f2fs_new_inode
- f2fs_lock_op
- alloc_nid
as node count still not
be increased, we will
loop in alloc_nid
- f2fs_write_node_pages
- f2fs_balance_fs_bg
- f2fs_sync_fs
- write_checkpoint
- block_operations
- f2fs_lock_all
- f2fs_lock_op
While creating new inode, we do not allocate and account nid atomically,
so that when there is almost no free nids left, we may encounter deadloop
like above stack.
In order to avoid that, reuse nm_i::available_nids for accounting free nids
and make nid allocation and counting being atomical during node creation.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>