Btrfs: don't re-enter when allocating a chunk

If we start running low on metadata space we will try to allocate a chunk,
which could then try to allocate a chunk to add the device entry.  The thing
is we allocate a chunk before we try really hard to make the allocation, so
we should be able to find space for the device entry.  Add a flag to the
trans handle so we know we're currently allocating a chunk so we can just
bail out if we try to allocate another chunk.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
This commit is contained in:
Josef Bacik 2012-12-18 09:16:16 -05:00
parent 2ab28f322f
commit c6b305a89b
3 changed files with 9 additions and 0 deletions

View file

@ -3570,6 +3570,10 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
int wait_for_alloc = 0;
int ret = 0;
/* Don't re-enter if we're already allocating a chunk */
if (trans->allocating_chunk)
return -ENOSPC;
space_info = __find_space_info(extent_root->fs_info, flags);
if (!space_info) {
ret = update_space_info(extent_root->fs_info, flags,
@ -3612,6 +3616,8 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
goto again;
}
trans->allocating_chunk = true;
/*
* If we have mixed data/metadata chunks we want to make sure we keep
* allocating mixed chunks instead of individual chunks.
@ -3638,6 +3644,7 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
check_system_chunk(trans, extent_root, flags);
ret = btrfs_alloc_chunk(trans, extent_root, flags);
trans->allocating_chunk = false;
if (ret < 0 && ret != -ENOSPC)
goto out;

View file

@ -385,6 +385,7 @@ start_transaction(struct btrfs_root *root, u64 num_items, int type,
h->qgroup_reserved = qgroup_reserved;
h->delayed_ref_elem.seq = 0;
h->type = type;
h->allocating_chunk = false;
INIT_LIST_HEAD(&h->qgroup_ref_list);
INIT_LIST_HEAD(&h->new_bgs);

View file

@ -68,6 +68,7 @@ struct btrfs_trans_handle {
struct btrfs_block_rsv *orig_rsv;
short aborted;
short adding_csums;
bool allocating_chunk;
enum btrfs_trans_type type;
/*
* this root is only needed to validate that the root passed to