From d278850eff3053ef166cf64c16f798dfe36278a2 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 29 Sep 2017 15:43:57 -0400 Subject: btrfs: remove delayed_ref_node from ref_head This is just excessive information in the ref_head, and makes the code complicated. It is a relic from when we had the heads and the refs in the same tree, which is no longer the case. With this removal I've cleaned up a bunch of the cruft around this old assumption as well. Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/delayed-ref.c | 126 +++++++++++++++++++++---------------------------- 1 file changed, 54 insertions(+), 72 deletions(-) (limited to 'fs/btrfs/delayed-ref.c') diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index 93ffa898df6d..b9b41c838da4 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -96,15 +96,15 @@ static struct btrfs_delayed_ref_head *htree_insert(struct rb_root *root, u64 bytenr; ins = rb_entry(node, struct btrfs_delayed_ref_head, href_node); - bytenr = ins->node.bytenr; + bytenr = ins->bytenr; while (*p) { parent_node = *p; entry = rb_entry(parent_node, struct btrfs_delayed_ref_head, href_node); - if (bytenr < entry->node.bytenr) + if (bytenr < entry->bytenr) p = &(*p)->rb_left; - else if (bytenr > entry->node.bytenr) + else if (bytenr > entry->bytenr) p = &(*p)->rb_right; else return entry; @@ -133,15 +133,15 @@ find_ref_head(struct rb_root *root, u64 bytenr, while (n) { entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node); - if (bytenr < entry->node.bytenr) + if (bytenr < entry->bytenr) n = n->rb_left; - else if (bytenr > entry->node.bytenr) + else if (bytenr > entry->bytenr) n = n->rb_right; else return entry; } if (entry && return_bigger) { - if (bytenr > entry->node.bytenr) { + if (bytenr > entry->bytenr) { n = rb_next(&entry->href_node); if (!n) n = rb_first(root); @@ -164,17 +164,17 @@ int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans, if (mutex_trylock(&head->mutex)) return 0; - refcount_inc(&head->node.refs); + refcount_inc(&head->refs); spin_unlock(&delayed_refs->lock); mutex_lock(&head->mutex); spin_lock(&delayed_refs->lock); - if (!head->node.in_tree) { + if (RB_EMPTY_NODE(&head->href_node)) { mutex_unlock(&head->mutex); - btrfs_put_delayed_ref(&head->node); + btrfs_put_delayed_ref_head(head); return -EAGAIN; } - btrfs_put_delayed_ref(&head->node); + btrfs_put_delayed_ref_head(head); return 0; } @@ -183,15 +183,10 @@ static inline void drop_delayed_ref(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_head *head, struct btrfs_delayed_ref_node *ref) { - if (btrfs_delayed_ref_is_head(ref)) { - head = btrfs_delayed_node_to_head(ref); - rb_erase(&head->href_node, &delayed_refs->href_root); - } else { - assert_spin_locked(&head->lock); - list_del(&ref->list); - if (!list_empty(&ref->add_list)) - list_del(&ref->add_list); - } + assert_spin_locked(&head->lock); + list_del(&ref->list); + if (!list_empty(&ref->add_list)) + list_del(&ref->add_list); ref->in_tree = 0; btrfs_put_delayed_ref(ref); atomic_dec(&delayed_refs->num_entries); @@ -380,8 +375,8 @@ again: head->processing = 1; WARN_ON(delayed_refs->num_heads_ready == 0); delayed_refs->num_heads_ready--; - delayed_refs->run_delayed_start = head->node.bytenr + - head->node.num_bytes; + delayed_refs->run_delayed_start = head->bytenr + + head->num_bytes; return head; } @@ -469,20 +464,16 @@ add_tail: */ static noinline void update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs, - struct btrfs_delayed_ref_node *existing, - struct btrfs_delayed_ref_node *update, + struct btrfs_delayed_ref_head *existing, + struct btrfs_delayed_ref_head *update, int *old_ref_mod_ret) { - struct btrfs_delayed_ref_head *existing_ref; - struct btrfs_delayed_ref_head *ref; int old_ref_mod; - existing_ref = btrfs_delayed_node_to_head(existing); - ref = btrfs_delayed_node_to_head(update); - BUG_ON(existing_ref->is_data != ref->is_data); + BUG_ON(existing->is_data != update->is_data); - spin_lock(&existing_ref->lock); - if (ref->must_insert_reserved) { + spin_lock(&existing->lock); + if (update->must_insert_reserved) { /* if the extent was freed and then * reallocated before the delayed ref * entries were processed, we can end up @@ -490,7 +481,7 @@ update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs, * the must_insert_reserved flag set. * Set it again here */ - existing_ref->must_insert_reserved = ref->must_insert_reserved; + existing->must_insert_reserved = update->must_insert_reserved; /* * update the num_bytes so we make sure the accounting @@ -500,22 +491,22 @@ update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs, } - if (ref->extent_op) { - if (!existing_ref->extent_op) { - existing_ref->extent_op = ref->extent_op; + if (update->extent_op) { + if (!existing->extent_op) { + existing->extent_op = update->extent_op; } else { - if (ref->extent_op->update_key) { - memcpy(&existing_ref->extent_op->key, - &ref->extent_op->key, - sizeof(ref->extent_op->key)); - existing_ref->extent_op->update_key = true; + if (update->extent_op->update_key) { + memcpy(&existing->extent_op->key, + &update->extent_op->key, + sizeof(update->extent_op->key)); + existing->extent_op->update_key = true; } - if (ref->extent_op->update_flags) { - existing_ref->extent_op->flags_to_set |= - ref->extent_op->flags_to_set; - existing_ref->extent_op->update_flags = true; + if (update->extent_op->update_flags) { + existing->extent_op->flags_to_set |= + update->extent_op->flags_to_set; + existing->extent_op->update_flags = true; } - btrfs_free_delayed_extent_op(ref->extent_op); + btrfs_free_delayed_extent_op(update->extent_op); } } /* @@ -523,23 +514,23 @@ update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs, * only need the lock for this case cause we could be processing it * currently, for refs we just added we know we're a-ok. */ - old_ref_mod = existing_ref->total_ref_mod; + old_ref_mod = existing->total_ref_mod; if (old_ref_mod_ret) *old_ref_mod_ret = old_ref_mod; existing->ref_mod += update->ref_mod; - existing_ref->total_ref_mod += update->ref_mod; + existing->total_ref_mod += update->ref_mod; /* * If we are going to from a positive ref mod to a negative or vice * versa we need to make sure to adjust pending_csums accordingly. */ - if (existing_ref->is_data) { - if (existing_ref->total_ref_mod >= 0 && old_ref_mod < 0) + if (existing->is_data) { + if (existing->total_ref_mod >= 0 && old_ref_mod < 0) delayed_refs->pending_csums -= existing->num_bytes; - if (existing_ref->total_ref_mod < 0 && old_ref_mod >= 0) + if (existing->total_ref_mod < 0 && old_ref_mod >= 0) delayed_refs->pending_csums += existing->num_bytes; } - spin_unlock(&existing_ref->lock); + spin_unlock(&existing->lock); } /* @@ -550,14 +541,13 @@ update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs, static noinline struct btrfs_delayed_ref_head * add_delayed_ref_head(struct btrfs_fs_info *fs_info, struct btrfs_trans_handle *trans, - struct btrfs_delayed_ref_node *ref, + struct btrfs_delayed_ref_head *head_ref, struct btrfs_qgroup_extent_record *qrecord, u64 bytenr, u64 num_bytes, u64 ref_root, u64 reserved, int action, int is_data, int *qrecord_inserted_ret, int *old_ref_mod, int *new_ref_mod) { struct btrfs_delayed_ref_head *existing; - struct btrfs_delayed_ref_head *head_ref = NULL; struct btrfs_delayed_ref_root *delayed_refs; int count_mod = 1; int must_insert_reserved = 0; @@ -593,26 +583,21 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info, delayed_refs = &trans->transaction->delayed_refs; - /* first set the basic ref node struct up */ - refcount_set(&ref->refs, 1); - ref->bytenr = bytenr; - ref->num_bytes = num_bytes; - ref->ref_mod = count_mod; - ref->type = 0; - ref->action = 0; - ref->is_head = 1; - ref->in_tree = 1; - ref->seq = 0; - - head_ref = btrfs_delayed_node_to_head(ref); + refcount_set(&head_ref->refs, 1); + head_ref->bytenr = bytenr; + head_ref->num_bytes = num_bytes; + head_ref->ref_mod = count_mod; head_ref->must_insert_reserved = must_insert_reserved; head_ref->is_data = is_data; INIT_LIST_HEAD(&head_ref->ref_list); INIT_LIST_HEAD(&head_ref->ref_add_list); + RB_CLEAR_NODE(&head_ref->href_node); head_ref->processing = 0; head_ref->total_ref_mod = count_mod; head_ref->qgroup_reserved = 0; head_ref->qgroup_ref_root = 0; + spin_lock_init(&head_ref->lock); + mutex_init(&head_ref->mutex); /* Record qgroup extent info if provided */ if (qrecord) { @@ -632,17 +617,14 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info, qrecord_inserted = 1; } - spin_lock_init(&head_ref->lock); - mutex_init(&head_ref->mutex); - - trace_add_delayed_ref_head(fs_info, ref, head_ref, action); + trace_add_delayed_ref_head(fs_info, head_ref, action); existing = htree_insert(&delayed_refs->href_root, &head_ref->href_node); if (existing) { WARN_ON(ref_root && reserved && existing->qgroup_ref_root && existing->qgroup_reserved); - update_existing_head_ref(delayed_refs, &existing->node, ref, + update_existing_head_ref(delayed_refs, existing, head_ref, old_ref_mod); /* * we've updated the existing ref, free the newly @@ -821,7 +803,7 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info, * insert both the head node and the new ref without dropping * the spin lock */ - head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record, + head_ref = add_delayed_ref_head(fs_info, trans, head_ref, record, bytenr, num_bytes, 0, 0, action, 0, &qrecord_inserted, old_ref_mod, new_ref_mod); @@ -888,7 +870,7 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info, * insert both the head node and the new ref without dropping * the spin lock */ - head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record, + head_ref = add_delayed_ref_head(fs_info, trans, head_ref, record, bytenr, num_bytes, ref_root, reserved, action, 1, &qrecord_inserted, old_ref_mod, new_ref_mod); @@ -920,7 +902,7 @@ int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info, delayed_refs = &trans->transaction->delayed_refs; spin_lock(&delayed_refs->lock); - add_delayed_ref_head(fs_info, trans, &head_ref->node, NULL, bytenr, + add_delayed_ref_head(fs_info, trans, head_ref, NULL, bytenr, num_bytes, 0, 0, BTRFS_UPDATE_DELAYED_HEAD, extent_op->is_data, NULL, NULL, NULL); -- cgit v1.2.3 From 3b60d436a165f890597d0226def17858973fa985 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 29 Sep 2017 15:43:58 -0400 Subject: btrfs: remove type argument from comp_tree_refs We can get this from the ref we've passed in. Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/delayed-ref.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'fs/btrfs/delayed-ref.c') diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index b9b41c838da4..a2973340a94f 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -41,9 +41,9 @@ struct kmem_cache *btrfs_delayed_extent_op_cachep; * compare two delayed tree backrefs with same bytenr and type */ static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2, - struct btrfs_delayed_tree_ref *ref1, int type) + struct btrfs_delayed_tree_ref *ref1) { - if (type == BTRFS_TREE_BLOCK_REF_KEY) { + if (ref1->node.type == BTRFS_TREE_BLOCK_REF_KEY) { if (ref1->root < ref2->root) return -1; if (ref1->root > ref2->root) @@ -223,8 +223,7 @@ static bool merge_ref(struct btrfs_trans_handle *trans, if ((ref->type == BTRFS_TREE_BLOCK_REF_KEY || ref->type == BTRFS_SHARED_BLOCK_REF_KEY) && comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref), - btrfs_delayed_node_to_tree_ref(next), - ref->type)) + btrfs_delayed_node_to_tree_ref(next))) goto next; if ((ref->type == BTRFS_EXTENT_DATA_REF_KEY || ref->type == BTRFS_SHARED_DATA_REF_KEY) && @@ -409,8 +408,7 @@ add_delayed_ref_tail_merge(struct btrfs_trans_handle *trans, if ((exist->type == BTRFS_TREE_BLOCK_REF_KEY || exist->type == BTRFS_SHARED_BLOCK_REF_KEY) && comp_tree_refs(btrfs_delayed_node_to_tree_ref(exist), - btrfs_delayed_node_to_tree_ref(ref), - ref->type)) + btrfs_delayed_node_to_tree_ref(ref))) goto add_tail; if ((exist->type == BTRFS_EXTENT_DATA_REF_KEY || exist->type == BTRFS_SHARED_DATA_REF_KEY) && -- cgit v1.2.3 From c7ad7c843965d8691269f581e132633a4ca9ef91 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 19 Oct 2017 14:15:58 -0400 Subject: btrfs: switch args for comp_*_refs Make it more consistent, we want the inserted ref to be compared against what's already in there. This will make the order go from lowest seq -> highest seq, which will make us more likely to make forward progress if there's a seqlock currently held. Signed-off-by: Josef Bacik Signed-off-by: David Sterba --- fs/btrfs/delayed-ref.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'fs/btrfs/delayed-ref.c') diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index a2973340a94f..bc940bb374cf 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -40,8 +40,8 @@ struct kmem_cache *btrfs_delayed_extent_op_cachep; /* * compare two delayed tree backrefs with same bytenr and type */ -static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2, - struct btrfs_delayed_tree_ref *ref1) +static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref1, + struct btrfs_delayed_tree_ref *ref2) { if (ref1->node.type == BTRFS_TREE_BLOCK_REF_KEY) { if (ref1->root < ref2->root) @@ -60,8 +60,8 @@ static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2, /* * compare two delayed data backrefs with same bytenr and type */ -static int comp_data_refs(struct btrfs_delayed_data_ref *ref2, - struct btrfs_delayed_data_ref *ref1) +static int comp_data_refs(struct btrfs_delayed_data_ref *ref1, + struct btrfs_delayed_data_ref *ref2) { if (ref1->node.type == BTRFS_EXTENT_DATA_REF_KEY) { if (ref1->root < ref2->root) -- cgit v1.2.3 From 1d148e5939f55c76d06108548c7c0226e55dde8e Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 19 Oct 2017 14:15:59 -0400 Subject: btrfs: add a comp_refs() helper Instead of open-coding the delayed ref comparisons, add a helper to do the comparisons generically and use that everywhere. We compare sequence numbers last for following patches. Signed-off-by: Josef Bacik Signed-off-by: David Sterba --- fs/btrfs/delayed-ref.c | 54 ++++++++++++++++++++++++++++---------------------- 1 file changed, 30 insertions(+), 24 deletions(-) (limited to 'fs/btrfs/delayed-ref.c') diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index bc940bb374cf..8c7d7db01f7a 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -85,6 +85,34 @@ static int comp_data_refs(struct btrfs_delayed_data_ref *ref1, return 0; } +static int comp_refs(struct btrfs_delayed_ref_node *ref1, + struct btrfs_delayed_ref_node *ref2, + bool check_seq) +{ + int ret = 0; + + if (ref1->type < ref2->type) + return -1; + if (ref1->type > ref2->type) + return 1; + if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY || + ref1->type == BTRFS_SHARED_BLOCK_REF_KEY) + ret = comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref1), + btrfs_delayed_node_to_tree_ref(ref2)); + else + ret = comp_data_refs(btrfs_delayed_node_to_data_ref(ref1), + btrfs_delayed_node_to_data_ref(ref2)); + if (ret) + return ret; + if (check_seq) { + if (ref1->seq < ref2->seq) + return -1; + if (ref1->seq > ref2->seq) + return 1; + } + return 0; +} + /* insert a new ref to head ref rbtree */ static struct btrfs_delayed_ref_head *htree_insert(struct rb_root *root, struct rb_node *node) @@ -217,18 +245,7 @@ static bool merge_ref(struct btrfs_trans_handle *trans, if (seq && next->seq >= seq) goto next; - if (next->type != ref->type) - goto next; - - if ((ref->type == BTRFS_TREE_BLOCK_REF_KEY || - ref->type == BTRFS_SHARED_BLOCK_REF_KEY) && - comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref), - btrfs_delayed_node_to_tree_ref(next))) - goto next; - if ((ref->type == BTRFS_EXTENT_DATA_REF_KEY || - ref->type == BTRFS_SHARED_DATA_REF_KEY) && - comp_data_refs(btrfs_delayed_node_to_data_ref(ref), - btrfs_delayed_node_to_data_ref(next))) + if (comp_refs(ref, next, false)) goto next; if (ref->action == next->action) { @@ -402,18 +419,7 @@ add_delayed_ref_tail_merge(struct btrfs_trans_handle *trans, exist = list_entry(href->ref_list.prev, struct btrfs_delayed_ref_node, list); /* No need to compare bytenr nor is_head */ - if (exist->type != ref->type || exist->seq != ref->seq) - goto add_tail; - - if ((exist->type == BTRFS_TREE_BLOCK_REF_KEY || - exist->type == BTRFS_SHARED_BLOCK_REF_KEY) && - comp_tree_refs(btrfs_delayed_node_to_tree_ref(exist), - btrfs_delayed_node_to_tree_ref(ref))) - goto add_tail; - if ((exist->type == BTRFS_EXTENT_DATA_REF_KEY || - exist->type == BTRFS_SHARED_DATA_REF_KEY) && - comp_data_refs(btrfs_delayed_node_to_data_ref(exist), - btrfs_delayed_node_to_data_ref(ref))) + if (comp_refs(exist, ref, true)) goto add_tail; /* Now we are sure we can merge */ -- cgit v1.2.3 From 0e0adbcfdc908684317c99a9bf5e13383f03b7ec Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 19 Oct 2017 14:16:00 -0400 Subject: btrfs: track refs in a rb_tree instead of a list If we get a significant amount of delayed refs for a single block (think modifying multiple snapshots) we can end up spending an ungodly amount of time looping through all of the entries trying to see if they can be merged. This is because we only add them to a list, so we have O(2n) for every ref head. This doesn't make any sense as we likely have refs for different roots, and so they cannot be merged. Tracking in a tree will allow us to break as soon as we hit an entry that doesn't match, making our worst case O(n). With this we can also merge entries more easily. Before we had to hope that matching refs were on the ends of our list, but with the tree we can search down to exact matches and merge them at insert time. Signed-off-by: Josef Bacik Signed-off-by: David Sterba --- fs/btrfs/backref.c | 5 ++- fs/btrfs/delayed-ref.c | 108 +++++++++++++++++++++++++------------------------ fs/btrfs/delayed-ref.h | 5 +-- fs/btrfs/disk-io.c | 10 +++-- fs/btrfs/extent-tree.c | 21 ++++++---- 5 files changed, 82 insertions(+), 67 deletions(-) (limited to 'fs/btrfs/delayed-ref.c') diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 523d2dba7745..7d0dc100a09a 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -773,6 +773,7 @@ static int add_delayed_refs(const struct btrfs_fs_info *fs_info, struct btrfs_key key; struct btrfs_key tmp_op_key; struct btrfs_key *op_key = NULL; + struct rb_node *n; int count; int ret = 0; @@ -782,7 +783,9 @@ static int add_delayed_refs(const struct btrfs_fs_info *fs_info, } spin_lock(&head->lock); - list_for_each_entry(node, &head->ref_list, list) { + for (n = rb_first(&head->ref_tree); n; n = rb_next(n)) { + node = rb_entry(n, struct btrfs_delayed_ref_node, + ref_node); if (node->seq > seq) continue; diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index 8c7d7db01f7a..83be8f9fd906 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -143,6 +143,34 @@ static struct btrfs_delayed_ref_head *htree_insert(struct rb_root *root, return NULL; } +static struct btrfs_delayed_ref_node* tree_insert(struct rb_root *root, + struct btrfs_delayed_ref_node *ins) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *node = &ins->ref_node; + struct rb_node *parent_node = NULL; + struct btrfs_delayed_ref_node *entry; + + while (*p) { + int comp; + + parent_node = *p; + entry = rb_entry(parent_node, struct btrfs_delayed_ref_node, + ref_node); + comp = comp_refs(ins, entry, true); + if (comp < 0) + p = &(*p)->rb_left; + else if (comp > 0) + p = &(*p)->rb_right; + else + return entry; + } + + rb_link_node(node, parent_node, p); + rb_insert_color(node, root); + return NULL; +} + /* * find an head entry based on bytenr. This returns the delayed ref * head if it was able to find one, or NULL if nothing was in that spot. @@ -212,7 +240,8 @@ static inline void drop_delayed_ref(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_node *ref) { assert_spin_locked(&head->lock); - list_del(&ref->list); + rb_erase(&ref->ref_node, &head->ref_tree); + RB_CLEAR_NODE(&ref->ref_node); if (!list_empty(&ref->add_list)) list_del(&ref->add_list); ref->in_tree = 0; @@ -229,24 +258,18 @@ static bool merge_ref(struct btrfs_trans_handle *trans, u64 seq) { struct btrfs_delayed_ref_node *next; + struct rb_node *node = rb_next(&ref->ref_node); bool done = false; - next = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node, - list); - while (!done && &next->list != &head->ref_list) { + while (!done && node) { int mod; - struct btrfs_delayed_ref_node *next2; - - next2 = list_next_entry(next, list); - - if (next == ref) - goto next; + next = rb_entry(node, struct btrfs_delayed_ref_node, ref_node); + node = rb_next(node); if (seq && next->seq >= seq) - goto next; - + break; if (comp_refs(ref, next, false)) - goto next; + break; if (ref->action == next->action) { mod = next->ref_mod; @@ -270,8 +293,6 @@ static bool merge_ref(struct btrfs_trans_handle *trans, WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY || ref->type == BTRFS_SHARED_BLOCK_REF_KEY); } -next: - next = next2; } return done; @@ -283,11 +304,12 @@ void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_head *head) { struct btrfs_delayed_ref_node *ref; + struct rb_node *node; u64 seq = 0; assert_spin_locked(&head->lock); - if (list_empty(&head->ref_list)) + if (RB_EMPTY_ROOT(&head->ref_tree)) return; /* We don't have too many refs to merge for data. */ @@ -304,22 +326,13 @@ void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, } spin_unlock(&fs_info->tree_mod_seq_lock); - ref = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node, - list); - while (&ref->list != &head->ref_list) { +again: + for (node = rb_first(&head->ref_tree); node; node = rb_next(node)) { + ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node); if (seq && ref->seq >= seq) - goto next; - - if (merge_ref(trans, delayed_refs, head, ref, seq)) { - if (list_empty(&head->ref_list)) - break; - ref = list_first_entry(&head->ref_list, - struct btrfs_delayed_ref_node, - list); continue; - } -next: - ref = list_next_entry(ref, list); + if (merge_ref(trans, delayed_refs, head, ref, seq)) + goto again; } } @@ -402,25 +415,19 @@ again: * Return 0 for insert. * Return >0 for merge. */ -static int -add_delayed_ref_tail_merge(struct btrfs_trans_handle *trans, - struct btrfs_delayed_ref_root *root, - struct btrfs_delayed_ref_head *href, - struct btrfs_delayed_ref_node *ref) +static int insert_delayed_ref(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_root *root, + struct btrfs_delayed_ref_head *href, + struct btrfs_delayed_ref_node *ref) { struct btrfs_delayed_ref_node *exist; int mod; int ret = 0; spin_lock(&href->lock); - /* Check whether we can merge the tail node with ref */ - if (list_empty(&href->ref_list)) - goto add_tail; - exist = list_entry(href->ref_list.prev, struct btrfs_delayed_ref_node, - list); - /* No need to compare bytenr nor is_head */ - if (comp_refs(exist, ref, true)) - goto add_tail; + exist = tree_insert(&href->ref_tree, ref); + if (!exist) + goto inserted; /* Now we are sure we can merge */ ret = 1; @@ -451,9 +458,7 @@ add_delayed_ref_tail_merge(struct btrfs_trans_handle *trans, drop_delayed_ref(trans, root, href, exist); spin_unlock(&href->lock); return ret; - -add_tail: - list_add_tail(&ref->list, &href->ref_list); +inserted: if (ref->action == BTRFS_ADD_DELAYED_REF) list_add_tail(&ref->add_list, &href->ref_add_list); atomic_inc(&root->num_entries); @@ -593,7 +598,7 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info, head_ref->ref_mod = count_mod; head_ref->must_insert_reserved = must_insert_reserved; head_ref->is_data = is_data; - INIT_LIST_HEAD(&head_ref->ref_list); + head_ref->ref_tree = RB_ROOT; INIT_LIST_HEAD(&head_ref->ref_add_list); RB_CLEAR_NODE(&head_ref->href_node); head_ref->processing = 0; @@ -685,7 +690,7 @@ add_delayed_tree_ref(struct btrfs_fs_info *fs_info, ref->is_head = 0; ref->in_tree = 1; ref->seq = seq; - INIT_LIST_HEAD(&ref->list); + RB_CLEAR_NODE(&ref->ref_node); INIT_LIST_HEAD(&ref->add_list); full_ref = btrfs_delayed_node_to_tree_ref(ref); @@ -699,7 +704,7 @@ add_delayed_tree_ref(struct btrfs_fs_info *fs_info, trace_add_delayed_tree_ref(fs_info, ref, full_ref, action); - ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref); + ret = insert_delayed_ref(trans, delayed_refs, head_ref, ref); /* * XXX: memory should be freed at the same level allocated. @@ -742,7 +747,7 @@ add_delayed_data_ref(struct btrfs_fs_info *fs_info, ref->is_head = 0; ref->in_tree = 1; ref->seq = seq; - INIT_LIST_HEAD(&ref->list); + RB_CLEAR_NODE(&ref->ref_node); INIT_LIST_HEAD(&ref->add_list); full_ref = btrfs_delayed_node_to_data_ref(ref); @@ -758,8 +763,7 @@ add_delayed_data_ref(struct btrfs_fs_info *fs_info, trace_add_delayed_data_ref(fs_info, ref, full_ref, action); - ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref); - + ret = insert_delayed_ref(trans, delayed_refs, head_ref, ref); if (ret > 0) kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref); } diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h index 1ce11858d727..a43af432f859 100644 --- a/fs/btrfs/delayed-ref.h +++ b/fs/btrfs/delayed-ref.h @@ -27,8 +27,7 @@ #define BTRFS_UPDATE_DELAYED_HEAD 4 /* not changing ref count on head ref */ struct btrfs_delayed_ref_node { - /*data/tree ref use list, stored in ref_head->ref_list. */ - struct list_head list; + struct rb_node ref_node; /* * If action is BTRFS_ADD_DELAYED_REF, also link this node to * ref_head->ref_add_list, then we do not need to iterate the @@ -92,7 +91,7 @@ struct btrfs_delayed_ref_head { struct mutex mutex; spinlock_t lock; - struct list_head ref_list; + struct rb_root ref_tree; /* accumulate add BTRFS_ADD_DELAYED_REF nodes to this ref_add_list. */ struct list_head ref_add_list; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index d1f396f72979..efce9a2fa9be 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -4113,7 +4113,7 @@ static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans, while ((node = rb_first(&delayed_refs->href_root)) != NULL) { struct btrfs_delayed_ref_head *head; - struct btrfs_delayed_ref_node *tmp; + struct rb_node *n; bool pin_bytes = false; head = rb_entry(node, struct btrfs_delayed_ref_head, @@ -4129,10 +4129,12 @@ static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans, continue; } spin_lock(&head->lock); - list_for_each_entry_safe_reverse(ref, tmp, &head->ref_list, - list) { + while ((n = rb_first(&head->ref_tree)) != NULL) { + ref = rb_entry(n, struct btrfs_delayed_ref_node, + ref_node); ref->in_tree = 0; - list_del(&ref->list); + rb_erase(&ref->ref_node, &head->ref_tree); + RB_CLEAR_NODE(&ref->ref_node); if (!list_empty(&ref->add_list)) list_del(&ref->add_list); atomic_dec(&delayed_refs->num_entries); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index fc9720e28005..673ac4e01dd0 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2519,7 +2519,7 @@ select_delayed_ref(struct btrfs_delayed_ref_head *head) { struct btrfs_delayed_ref_node *ref; - if (list_empty(&head->ref_list)) + if (RB_EMPTY_ROOT(&head->ref_tree)) return NULL; /* @@ -2532,8 +2532,8 @@ select_delayed_ref(struct btrfs_delayed_ref_head *head) return list_first_entry(&head->ref_add_list, struct btrfs_delayed_ref_node, add_list); - ref = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node, - list); + ref = rb_entry(rb_first(&head->ref_tree), + struct btrfs_delayed_ref_node, ref_node); ASSERT(list_empty(&ref->add_list)); return ref; } @@ -2593,7 +2593,7 @@ static int cleanup_ref_head(struct btrfs_trans_handle *trans, spin_unlock(&head->lock); spin_lock(&delayed_refs->lock); spin_lock(&head->lock); - if (!list_empty(&head->ref_list) || head->extent_op) { + if (!RB_EMPTY_ROOT(&head->ref_tree) || head->extent_op) { spin_unlock(&head->lock); spin_unlock(&delayed_refs->lock); return 1; @@ -2740,7 +2740,8 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, actual_count++; ref->in_tree = 0; - list_del(&ref->list); + rb_erase(&ref->ref_node, &locked_ref->ref_tree); + RB_CLEAR_NODE(&ref->ref_node); if (!list_empty(&ref->add_list)) list_del(&ref->add_list); /* @@ -3138,6 +3139,7 @@ static noinline int check_delayed_ref(struct btrfs_root *root, struct btrfs_delayed_data_ref *data_ref; struct btrfs_delayed_ref_root *delayed_refs; struct btrfs_transaction *cur_trans; + struct rb_node *node; int ret = 0; cur_trans = root->fs_info->running_transaction; @@ -3170,7 +3172,12 @@ static noinline int check_delayed_ref(struct btrfs_root *root, spin_unlock(&delayed_refs->lock); spin_lock(&head->lock); - list_for_each_entry(ref, &head->ref_list, list) { + /* + * XXX: We should replace this with a proper search function in the + * future. + */ + for (node = rb_first(&head->ref_tree); node; node = rb_next(node)) { + ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node); /* If it's a shared ref we know a cross reference exists */ if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) { ret = 1; @@ -7141,7 +7148,7 @@ static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans, goto out_delayed_unlock; spin_lock(&head->lock); - if (!list_empty(&head->ref_list)) + if (!RB_EMPTY_ROOT(&head->ref_tree)) goto out; if (head->extent_op) { -- cgit v1.2.3