Btrfs: Replace extent tree preallocation code with some bit radix magic. (26b8003f) · Commits · 戴 / test

fs/btrfs/ctree.h

+1 −6

Original line number	Diff line number	Diff line
		@@ -299,12 +299,7 @@ struct btrfs_fs_info {
		struct radix_tree_root block_group_radix;
		struct radix_tree_root block_group_data_radix;
		struct radix_tree_root extent_map_radix;

		u64 extent_tree_insert[BTRFS_MAX_LEVEL * 6];
		int extent_tree_insert_nr;
		u64 extent_tree_prealloc[BTRFS_MAX_LEVEL * 6];
		int extent_tree_prealloc_nr;

		struct radix_tree_root extent_ins_radix;
		u64 generation;
		struct btrfs_transaction *running_transaction;
		struct btrfs_super_block *disk_super;

fs/btrfs/disk-io.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -427,6 +427,7 @@ struct btrfs_root open_ctree(struct super_block sb)
		init_bit_radix(&fs_info->pinned_radix);
		init_bit_radix(&fs_info->pending_del_radix);
		init_bit_radix(&fs_info->extent_map_radix);
		init_bit_radix(&fs_info->extent_ins_radix);
		INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
		INIT_RADIX_TREE(&fs_info->block_group_radix, GFP_KERNEL);
		INIT_RADIX_TREE(&fs_info->block_group_data_radix, GFP_KERNEL);
		@@ -443,8 +444,6 @@ struct btrfs_root open_ctree(struct super_block sb)
		fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
		fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
		fs_info->do_barriers = 1;
		fs_info->extent_tree_insert_nr = 0;
		fs_info->extent_tree_prealloc_nr = 0;
		fs_info->closing = 0;

		INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);

fs/btrfs/extent-tree.c

+43 −187

Original line number	Diff line number	Diff line
		@@ -22,12 +22,6 @@
		#include "print-tree.h"
		#include "transaction.h"

		static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
		*orig_root, u64 num_blocks, u64 empty_size,
		u64 search_start,
		u64 search_end, u64 hint_block,
		struct btrfs_key *ins, u64 exclude_start,
		u64 exclude_nr, int data);
		static int finish_current_insert(struct btrfs_trans_handle *trans, struct
		btrfs_root *extent_root);
		static int del_pending_extents(struct btrfs_trans_handle *trans, struct
		@@ -174,9 +168,6 @@ static u64 find_search_start(struct btrfs_root *root,

		if (cache->data)
		goto out;
		if (num > 1) {
		last = max(last, cache->last_prealloc);
		}
		again:
		ret = cache_block_group(root, cache);
		if (ret)
		@@ -374,18 +365,12 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
		struct btrfs_key key;
		struct btrfs_leaf *l;
		struct btrfs_extent_item *item;
		struct btrfs_key ins;
		u32 refs;

		path = btrfs_alloc_path();
		if (!path)
		return -ENOMEM;
		ret = find_free_extent(trans, root->fs_info->extent_root, 0, 0, 0,
		(u64)-1, 0, &ins, 0, 0, 0);
		if (ret) {
		btrfs_free_path(path);
		return ret;
		}

		key.objectid = blocknr;
		key.flags = 0;
		btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
		@@ -532,13 +517,7 @@ static int write_one_cache_group(struct btrfs_trans_handle *trans,
		int pending_ret;
		struct btrfs_root *extent_root = root->fs_info->extent_root;
		struct btrfs_block_group_item *bi;
		struct btrfs_key ins;

		ret = find_free_extent(trans, extent_root, 0, 0, 0, (u64)-1, 0, &ins,
		0, 0, 0);
		/* FIXME, set bit to recalc cache groups on next mount */
		if (ret)
		return ret;
		ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
		if (ret < 0)
		goto fail;
		@@ -706,14 +685,6 @@ static int update_block_group(struct btrfs_trans_handle *trans,
		return 0;
		}

		static int try_remove_page(struct address_space *mapping, unsigned long index)
		{
		int ret;
		return 0;
		ret = invalidate_mapping_pages(mapping, index, index);
		return ret;
		}

		int btrfs_copy_pinned(struct btrfs_root root, struct radix_tree_root copy)
		{
		unsigned long gang[8];
		@@ -732,6 +703,9 @@ int btrfs_copy_pinned(struct btrfs_root root, struct radix_tree_root copy)
		last = gang[i] + 1;
		}
		}
		ret = find_first_radix_bit(&root->fs_info->extent_ins_radix, gang, 0,
		ARRAY_SIZE(gang));
		WARN_ON(ret);
		return 0;
		}

		@@ -740,7 +714,6 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
		struct radix_tree_root *unpin_radix)
		{
		unsigned long gang[8];
		struct inode *btree_inode = root->fs_info->btree_inode;
		struct btrfs_block_group_cache *block_group;
		u64 first = 0;
		int ret;
		@@ -765,14 +738,9 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
		block_group->pinned--;
		if (gang[i] < block_group->last_alloc)
		block_group->last_alloc = gang[i];
		if (gang[i] < block_group->last_prealloc)
		block_group->last_prealloc = gang[i];
		if (!block_group->data)
		set_radix_bit(extent_radix, gang[i]);
		}
		try_remove_page(btree_inode->i_mapping,
		gang[i] << (PAGE_CACHE_SHIFT -
		btree_inode->i_blkbits));
		}
		}
		return 0;
		@@ -785,7 +753,8 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct
		struct btrfs_extent_item extent_item;
		int i;
		int ret;
		u64 super_blocks_used;
		int err;
		unsigned long gang[8];
		struct btrfs_fs_info *info = extent_root->fs_info;

		btrfs_set_extent_refs(&extent_item, 1);
		@@ -794,16 +763,21 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct
		btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
		btrfs_set_extent_owner(&extent_item, extent_root->root_key.objectid);

		for (i = 0; i < extent_root->fs_info->extent_tree_insert_nr; i++) {
		ins.objectid = extent_root->fs_info->extent_tree_insert[i];
		super_blocks_used = btrfs_super_blocks_used(&info->super_copy);
		btrfs_set_super_blocks_used(&info->super_copy,
		super_blocks_used + 1);
		ret = btrfs_insert_item(trans, extent_root, &ins, &extent_item,
		while(1) {
		ret = find_first_radix_bit(&info->extent_ins_radix, gang, 0,
		ARRAY_SIZE(gang));
		if (!ret)
		break;

		for (i = 0; i < ret; i++) {
		ins.objectid = gang[i];
		err = btrfs_insert_item(trans, extent_root, &ins,
		&extent_item,
		sizeof(extent_item));
		BUG_ON(ret);
		clear_radix_bit(&info->extent_ins_radix, gang[i]);
		WARN_ON(err);
		}
		}
		extent_root->fs_info->extent_tree_insert_nr = 0;
		return 0;
		}

		@@ -856,7 +830,6 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
		struct btrfs_root *extent_root = info->extent_root;
		int ret;
		struct btrfs_extent_item *ei;
		struct btrfs_key ins;
		u32 refs;

		key.objectid = blocknr;
		@@ -868,12 +841,6 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
		if (!path)
		return -ENOMEM;

		ret = find_free_extent(trans, root, 0, 0, 0, (u64)-1, 0, &ins, 0, 0, 0);
		if (ret) {
		btrfs_free_path(path);
		return ret;
		}

		ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
		if (ret < 0)
		return ret;
		@@ -1003,35 +970,17 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
		struct btrfs_root * root = orig_root->fs_info->extent_root;
		struct btrfs_fs_info *info = root->fs_info;
		int total_needed = num_blocks;
		int total_found = 0;
		int fill_prealloc = 0;
		int level;
		struct btrfs_block_group_cache *block_group;
		int full_scan = 0;
		int wrapped = 0;
		u64 limit;

		WARN_ON(num_blocks < 1);
		ins->flags = 0;
		btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);

		level = btrfs_header_level(btrfs_buffer_header(root->node));
		if (num_blocks == 0) {
		fill_prealloc = 1;
		num_blocks = 1;
		total_needed = (min(level + 1, BTRFS_MAX_LEVEL)) * 6;
		}
		if (fill_prealloc) {
		u64 first;
		int nr = info->extent_tree_prealloc_nr;
		first = info->extent_tree_prealloc[nr - 1];
		if (info->extent_tree_prealloc_nr >= total_needed &&
		first >= search_start) {
		ins->objectid = info->extent_tree_prealloc[0];
		ins->offset = 1;
		return 0;
		}
		info->extent_tree_prealloc_nr = 0;
		}
		if (search_end == (u64)-1)
		search_end = btrfs_super_total_blocks(&info->super_copy);
		if (hint_block) {
		@@ -1091,10 +1040,6 @@ check_failed:
		l = btrfs_buffer_leaf(path->nodes[0]);
		slot = path->slots[0];
		if (slot >= btrfs_header_nritems(&l->header)) {
		if (fill_prealloc) {
		info->extent_tree_prealloc_nr = 0;
		total_found = 0;
		}
		if (start_found)
		limit = last_block +
		(block_group->key.offset >> 1);
		@@ -1170,68 +1115,22 @@ check_pending:
		}
		for (test_block = ins->objectid;
		test_block < ins->objectid + num_blocks; test_block++) {
		if (test_radix_bit(&info->pinned_radix, test_block)) {
		if (test_radix_bit(&info->pinned_radix, test_block) \|\|
		test_radix_bit(&info->extent_ins_radix, test_block)) {
		search_start = test_block + 1;
		goto new_group;
		}
		}
		if (!fill_prealloc && info->extent_tree_insert_nr) {
		u64 last =
		info->extent_tree_insert[info->extent_tree_insert_nr - 1];
		if (ins->objectid + num_blocks >
		info->extent_tree_insert[0] &&
		ins->objectid <= last) {
		search_start = last + 1;
		WARN_ON(!full_scan);
		goto new_group;
		}
		}
		if (!fill_prealloc && info->extent_tree_prealloc_nr) {
		u64 first =
		info->extent_tree_prealloc[info->extent_tree_prealloc_nr - 1];
		if (ins->objectid + num_blocks > first &&
		ins->objectid <= info->extent_tree_prealloc[0]) {
		search_start = info->extent_tree_prealloc[0] + 1;
		goto new_group;
		}
		}
		if (exclude_nr > 0 && (ins->objectid + num_blocks > exclude_start &&
		ins->objectid < exclude_start + exclude_nr)) {
		search_start = exclude_start + exclude_nr;
		goto new_group;
		}
		if (fill_prealloc) {
		int nr;
		test_block = ins->objectid;
		if (test_block - info->extent_tree_prealloc[total_needed - 1] >=
		leaf_range(root)) {
		total_found = 0;
		info->extent_tree_prealloc_nr = total_found;
		}
		while(test_block < ins->objectid + ins->offset &&
		total_found < total_needed) {
		nr = total_needed - total_found - 1;
		BUG_ON(nr < 0);
		info->extent_tree_prealloc[nr] = test_block;
		total_found++;
		test_block++;
		}
		if (total_found < total_needed) {
		search_start = test_block;
		goto new_group;
		}
		info->extent_tree_prealloc_nr = total_found;
		}
		if (!data) {
		block_group = btrfs_lookup_block_group(info, ins->objectid);
		if (block_group) {
		if (fill_prealloc)
		block_group->last_prealloc =
		info->extent_tree_prealloc[total_needed-1];
		else
		if (block_group)
		trans->block_group = block_group;
		}
		}
		ins->offset = num_blocks;
		btrfs_free_path(path);
		return 0;
		@@ -1278,85 +1177,41 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
		int pending_ret;
		u64 super_blocks_used;
		u64 search_start = 0;
		u64 exclude_start = 0;
		u64 exclude_nr = 0;
		struct btrfs_fs_info *info = root->fs_info;
		struct btrfs_root *extent_root = info->extent_root;
		struct btrfs_extent_item extent_item;
		struct btrfs_key prealloc_key;

		btrfs_set_extent_refs(&extent_item, 1);
		btrfs_set_extent_owner(&extent_item, owner);

		if (root == extent_root) {
		int nr;
		BUG_ON(info->extent_tree_prealloc_nr == 0);
		BUG_ON(num_blocks != 1);
		ins->offset = 1;
		info->extent_tree_prealloc_nr--;
		nr = info->extent_tree_prealloc_nr;
		ins->objectid = info->extent_tree_prealloc[nr];
		info->extent_tree_insert[info->extent_tree_insert_nr++] =
		ins->objectid;
		ret = update_block_group(trans, root,
		ins->objectid, ins->offset, 1, 0, 0);
		WARN_ON(info->extent_tree_insert_nr >
		ARRAY_SIZE(info->extent_tree_insert));
		BUG_ON(ret);
		return 0;
		}

		/*
		* if we're doing a data allocation, preallocate room in the
		* extent tree first. This way the extent tree blocks end up
		* in the correct block group.
		*/
		if (data) {
		ret = find_free_extent(trans, root, 0, 0, 0,
		search_end, 0, &prealloc_key, 0, 0, 0);
		BUG_ON(ret);
		if (ret)
		return ret;
		exclude_nr = info->extent_tree_prealloc_nr;
		exclude_start = info->extent_tree_prealloc[exclude_nr - 1];
		}

		/* do the real allocation */
		WARN_ON(num_blocks < 1);
		ret = find_free_extent(trans, root, num_blocks, empty_size,
		search_start, search_end, hint_block, ins,
		exclude_start, exclude_nr, data);
		trans->alloc_exclude_start,
		trans->alloc_exclude_nr, data);
		BUG_ON(ret);
		if (ret)
		return ret;

		/*
		* if we're doing a metadata allocation, preallocate space in the
		* extent tree second. This way, we don't create a tiny hole
		* in the allocation map between any unused preallocation blocks
		* and the metadata block we're actually allocating. On disk,
		* it'll go:
		* [block we've allocated], [used prealloc 1], [ unused prealloc ]
		* The unused prealloc will get reused the next time around.
		*/
		if (!data) {
		exclude_start = ins->objectid;
		exclude_nr = ins->offset;
		hint_block = exclude_start + exclude_nr;
		ret = find_free_extent(trans, root, 0, 0, search_start,
		search_end, hint_block,
		&prealloc_key, exclude_start,
		exclude_nr, 0);
		BUG_ON(ret);
		if (ret)
		return ret;
		}

		super_blocks_used = btrfs_super_blocks_used(&info->super_copy);
		btrfs_set_super_blocks_used(&info->super_copy, super_blocks_used +
		num_blocks);

		if (root == extent_root) {
		BUG_ON(num_blocks != 1);
		set_radix_bit(&root->fs_info->extent_ins_radix, ins->objectid);
		goto update_block;
		}

		WARN_ON(trans->alloc_exclude_nr);
		trans->alloc_exclude_start = ins->objectid;
		trans->alloc_exclude_nr = ins->offset;
		ret = btrfs_insert_item(trans, extent_root, ins, &extent_item,
		sizeof(extent_item));

		trans->alloc_exclude_start = 0;
		trans->alloc_exclude_nr = 0;

		BUG_ON(ret);
		finish_current_insert(trans, extent_root);
		pending_ret = del_pending_extents(trans, extent_root);
		@@ -1366,6 +1221,8 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
		if (pending_ret) {
		return pending_ret;
		}

		update_block:
		ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0,
		data);
		BUG_ON(ret);
		@@ -1750,7 +1607,6 @@ int btrfs_read_block_groups(struct btrfs_root *root)
		memcpy(&cache->key, &found_key, sizeof(found_key));
		cache->last_alloc = cache->key.objectid;
		cache->first_free = cache->key.objectid;
		cache->last_prealloc = cache->key.objectid;
		cache->pinned = 0;
		cache->cached = 0;

fs/btrfs/transaction.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -109,6 +109,8 @@ struct btrfs_trans_handle btrfs_start_transaction(struct btrfs_root root,
		h->blocks_reserved = num_blocks;
		h->blocks_used = 0;
		h->block_group = NULL;
		h->alloc_exclude_nr = 0;
		h->alloc_exclude_start = 0;
		root->fs_info->running_transaction->use_count++;
		mutex_unlock(&root->fs_info->trans_mutex);
		return h;

fs/btrfs/transaction.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -39,6 +39,8 @@ struct btrfs_trans_handle {
		unsigned long blocks_used;
		struct btrfs_transaction *transaction;
		struct btrfs_block_group_cache *block_group;
		u64 alloc_exclude_start;
		u64 alloc_exclude_nr;
		};

Admin message