Btrfs: Replace extent tree preallocation code with some bit radix magic.
authorChris Mason <chris.mason@oracle.com>
Thu, 9 Aug 2007 00:17:12 +0000 (20:17 -0400)
committerDavid Woodhouse <dwmw2@hera.kernel.org>
Thu, 9 Aug 2007 00:17:12 +0000 (20:17 -0400)
Signed-off-by: Chris Mason <chris.mason@oracle.com>
fs/btrfs/ctree.h
fs/btrfs/disk-io.c
fs/btrfs/extent-tree.c
fs/btrfs/transaction.c
fs/btrfs/transaction.h

index 8b7d01597f4fdd57b0d3065aa66945f434787811..59e09e37ab9306f8cef1e26e50f352cb9317cafa 100644 (file)
@@ -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;
index c948416fea3aca8f9673ef98eca60e3c85a77eb1..192211274ce5cf692e18688430c65ad88eff5bdd 100644 (file)
@@ -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);
index f7d76d34fc3752a22d26761d4b8f487c8166d6b4..ba50bd7b9a785f5fea638fc6fbadc4c650eee720 100644 (file)
 #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,
-                                       sizeof(extent_item));
-               BUG_ON(ret);
+       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));
+                       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);
@@ -1170,67 +1115,21 @@ 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
-                               trans->block_group = block_group;
-               }
+               if (block_group)
+                       trans->block_group = block_group;
        }
        ins->offset = num_blocks;
        btrfs_free_path(path);
@@ -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;
 
index 88b0752550b63d0a84cebc2580cce4340f6b9c16..e64ecec3f52eab3773f4b276ec29059e6774151d 100644 (file)
@@ -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;
index 8b2714e65562985ee64f01fb11c11e5e4eb8ea51..65a395eeca917c865f21155c78bef8ea8f2adf80 100644 (file)
@@ -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;
 };