Btrfs: fix metadata dirty throttling limits (585ad2c3) · Commits · 戴 / test

Once a metadata block has been written, it must be recowed, so the btrfs dirty balancing call has a check to make sure a fair amount of metadata was actually dirty before it started writing it back to disk. A previous commit had changed the dirty tracking for metadata without updating the btrfs dirty balancing checks. This commit switches it to use the correct counter. Signed-off-by:

Chris Mason <chris.mason@oracle.com>

fs/btrfs/disk-io.c

+2 −5

Original line number	Diff line number	Diff line
		@@ -2378,17 +2378,14 @@ void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
		* looks as though older kernels can get into trouble with
		* this code, they end up stuck in balance_dirty_pages forever
		*/
		struct extent_io_tree *tree;
		u64 num_dirty;
		u64 start = 0;
		unsigned long thresh = 32 * 1024 * 1024;
		tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;

		if (current->flags & PF_MEMALLOC)
		return;

		num_dirty = count_range_bits(tree, &start, (u64)-1,
		thresh, EXTENT_DIRTY);
		num_dirty = root->fs_info->dirty_metadata_bytes;

		if (num_dirty > thresh) {
		balance_dirty_pages_ratelimited_nr(
		root->fs_info->btree_inode->i_mapping, 1);

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