From: Jeff Mahoney <je...@suse.com>
Rather than iterate over all outstanding backrefs to resolve missing keys,
use a separate list that only contains refs that need missing keys resolved.
Once the missing key is resolved, move the ref to the pending list.
Signed-off-by: Jeff Mahoney <je...@suse.com>
---
backref.c | 28 +++++++++++++++++-----------
1 file changed, 17 insertions(+), 11 deletions(-)
diff --git a/backref.c b/backref.c
index be3376a..1d670ee 100644
--- a/backref.c
+++ b/backref.c
@@ -137,11 +137,13 @@ static struct __prelim_ref *list_first_pref(struct
list_head *head)
struct pref_state {
struct list_head pending;
+ struct list_head pending_missing_keys;
};
static void init_pref_state(struct pref_state *prefstate)
{
INIT_LIST_HEAD(&prefstate->pending);
+ INIT_LIST_HEAD(&prefstate->pending_missing_keys);
}
/*
@@ -188,7 +190,7 @@ static int __add_prelim_ref(struct pref_state *prefstate,
u64 root_id,
u64 parent, u64 wanted_disk_byte, int count,
gfp_t gfp_mask)
{
- struct list_head *head = &prefstate->pending;
+ struct list_head *head;
struct __prelim_ref *ref;
if (root_id == BTRFS_DATA_RELOC_TREE_OBJECTID)
@@ -199,16 +201,20 @@ static int __add_prelim_ref(struct pref_state *prefstate,
u64 root_id,
return -ENOMEM;
ref->root_id = root_id;
- if (key)
+ if (key) {
ref->key_for_search = *key;
- else
+ head = &prefstate->pending;
+ } else {
memset(&ref->key_for_search, 0, sizeof(ref->key_for_search));
+ head = &prefstate->pending_missing_keys;
+ }
ref->inode_list = NULL;
ref->level = level;
ref->count = count;
ref->parent = parent;
ref->wanted_disk_byte = wanted_disk_byte;
+
list_add_tail(&ref->list, head);
return 0;
@@ -454,18 +460,15 @@ static inline int ref_for_same_block(struct __prelim_ref
*ref1,
static int __add_missing_keys(struct btrfs_fs_info *fs_info,
struct pref_state *prefstate)
{
- struct list_head *head = &prefstate->pending;
- struct list_head *pos;
struct extent_buffer *eb;
- list_for_each(pos, head) {
+ while(!list_empty(&prefstate->pending_missing_keys)) {
struct __prelim_ref *ref;
- ref = list_entry(pos, struct __prelim_ref, list);
+ ref = list_first_pref(&prefstate->pending_missing_keys);
- if (ref->parent)
- continue;
- if (ref->key_for_search.type)
- continue;
+ ASSERT(ref->root_id);
+ ASSERT(!ref->parent);
+ ASSERT(ref->key_for_search.type);
BUG_ON(!ref->wanted_disk_byte);
eb = read_tree_block(fs_info->tree_root, ref->wanted_disk_byte,
fs_info->tree_root->nodesize, 0);
@@ -478,6 +481,7 @@ static int __add_missing_keys(struct btrfs_fs_info *fs_info,
else
btrfs_node_key_to_cpu(eb, &ref->key_for_search, 0);
free_extent_buffer(eb);
+ list_move(&ref->list, &prefstate->pending);
}
return 0;
}
@@ -808,6 +812,8 @@ static int find_parent_nodes(struct btrfs_trans_handle
*trans,
__merge_refs(&prefstate, 2);
+ BUG_ON(!list_empty(&prefstate.pending_missing_keys));
+
while (!list_empty(&prefstate.pending)) {
ref = list_first_pref(&prefstate.pending);
WARN_ON(ref->count < 0);
--
2.11.0
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
