Introduce btrfs_update_block_group_priority() to update
block_groups::priority. It will move block group from old tree
to new tree if need.
Signed-off-by: Su Yue <suy.f...@cn.fujitsu.com>
---
fs/btrfs/extent-tree.c | 76 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 76 insertions(+)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b559c9a9afc6..5ea1f2e40701 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -11466,3 +11466,79 @@ void btrfs_remove_block_group_priority(struct
btrfs_block_group_cache *cache)
spin_unlock(&cache->lock);
up_write(&pt->groups_sem);
}
+
+static inline struct btrfs_priority_tree *
+find_priority_tree(struct btrfs_space_info *sinfo, u64 flags, int level)
+{
+ int index = btrfs_bg_flags_to_raid_index(flags);
+
+ return search_priority_tree(&sinfo->priority_trees[index], level);
+}
+
+void btrfs_update_block_group_priority(struct btrfs_block_group_cache *cache)
+{
+ struct btrfs_priority_tree *old_tree, *new_tree;
+ struct rw_semaphore *front_sem, *back_sem;
+ long priority;
+ int old_level, new_level;
+
+ if (!is_priority_alloc_enabled(cache->fs_info))
+ return;
+
+ spin_lock(&cache->lock);
+ if (cache->priority != PRIORITY_BG_UPDATING) {
+ spin_unlock(&cache->lock);
+ return;
+ }
+
+ old_level = cache->priority_tree->level;
+ priority = compute_block_group_priority(cache);
+ new_level = compute_priority_level(cache->fs_info, priority);
+
+ /* no need to move the block group */
+ if (old_level == new_level) {
+ cache->priority = priority;
+ spin_unlock(&cache->lock);
+ return;
+ }
+ spin_unlock(&cache->lock);
+
+ old_tree = cache->priority_tree;
+ new_tree = find_priority_tree(cache->space_info, cache->flags,
+ new_level);
+
+ if (!old_tree || !new_tree) {
+ btrfs_err(cache->fs_info,
+"can't found priority tree %d for block_group %llu old level %d new priority
%ld",
+ old_tree ? new_level : old_level,
+ cache->key.objectid, old_level, priority);
+ BUG();
+ }
+
+ if (old_level > new_level) {
+ front_sem = &old_tree->groups_sem;
+ back_sem = &new_tree->groups_sem;
+ } else {
+ front_sem = &new_tree->groups_sem;
+ back_sem = &old_tree->groups_sem;
+ }
+
+ down_write(front_sem);
+ down_write(back_sem);
+ spin_lock(&cache->lock);
+
+ /* the block group was removed/is removing */
+ if (cache->priority != PRIORITY_BG_UPDATING ||
+ priority != compute_block_group_priority(cache) ||
+ old_tree != cache->priority_tree)
+ goto out;
+
+ unlink_block_group_priority(old_tree, cache);
+ cache->priority = priority;
+ link_block_group_priority(new_tree, cache);
+ cache->priority_tree = new_tree;
+out:
+ spin_unlock(&cache->lock);
+ up_write(front_sem);
+ up_write(back_sem);
+}
--
2.19.1
