From 5da9d01b66458b180a6bee0e637a1d0a3effc622 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Sun, 16 May 2010 10:46:25 -0400 Subject: [PATCH] Btrfs: Shrink delay allocated space in a synchronized Shrink delayed allocation space in a synchronized manner is more controllable than flushing all delay allocated space in an async thread. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 6 +- fs/btrfs/disk-io.c | 6 -- fs/btrfs/extent-tree.c | 165 +++++++++++++++++-------------------------------- fs/btrfs/inode.c | 32 ++++++++++ 4 files changed, 88 insertions(+), 121 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index a68f346..85c7b95 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -700,10 +700,6 @@ struct btrfs_space_info { struct list_head list; - /* for controlling how we free up space for allocations */ - wait_queue_head_t flush_wait; - int flushing; - /* for block groups in our same type */ struct list_head block_groups[BTRFS_NR_RAID_TYPES]; spinlock_t lock; @@ -928,7 +924,6 @@ struct btrfs_fs_info { struct btrfs_workers endio_meta_write_workers; struct btrfs_workers endio_write_workers; struct btrfs_workers submit_workers; - struct btrfs_workers enospc_workers; /* * fixup workers take dirty pages that didn't properly go through * the cow mechanism and make them safe to write. It happens @@ -2312,6 +2307,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, u32 min_type); int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput); +int btrfs_start_one_delalloc_inode(struct btrfs_root *root, int delay_iput); int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, struct extent_state **cached_state); int btrfs_writepages(struct address_space *mapping, diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index feca041..05f26ac 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1759,9 +1759,6 @@ struct btrfs_root *open_ctree(struct super_block *sb, min_t(u64, fs_devices->num_devices, fs_info->thread_pool_size), &fs_info->generic_worker); - btrfs_init_workers(&fs_info->enospc_workers, "enospc", - fs_info->thread_pool_size, - &fs_info->generic_worker); /* a higher idle thresh on the submit workers makes it much more * likely that bios will be send down in a sane order to the @@ -1809,7 +1806,6 @@ struct btrfs_root *open_ctree(struct super_block *sb, btrfs_start_workers(&fs_info->endio_meta_workers, 1); btrfs_start_workers(&fs_info->endio_meta_write_workers, 1); btrfs_start_workers(&fs_info->endio_write_workers, 1); - btrfs_start_workers(&fs_info->enospc_workers, 1); fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super); fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages, @@ -2040,7 +2036,6 @@ fail_sb_buffer: btrfs_stop_workers(&fs_info->endio_meta_write_workers); btrfs_stop_workers(&fs_info->endio_write_workers); btrfs_stop_workers(&fs_info->submit_workers); - btrfs_stop_workers(&fs_info->enospc_workers); fail_iput: invalidate_inode_pages2(fs_info->btree_inode->i_mapping); iput(fs_info->btree_inode); @@ -2473,7 +2468,6 @@ int close_ctree(struct btrfs_root *root) btrfs_stop_workers(&fs_info->endio_meta_write_workers); btrfs_stop_workers(&fs_info->endio_write_workers); btrfs_stop_workers(&fs_info->submit_workers); - btrfs_stop_workers(&fs_info->enospc_workers); btrfs_close_devices(fs_info->fs_devices); btrfs_mapping_tree_free(&fs_info->mapping_tree); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 2c95507..f32b161 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -74,6 +74,9 @@ static void dump_space_info(struct btrfs_space_info *info, u64 bytes, static int maybe_allocate_chunk(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_space_info *sinfo, u64 num_bytes); +static int shrink_delalloc(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_space_info *sinfo, u64 to_reclaim); static noinline int block_group_cache_done(struct btrfs_block_group_cache *cache) @@ -2693,7 +2696,6 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags, for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) INIT_LIST_HEAD(&found->block_groups[i]); init_rwsem(&found->groups_sem); - init_waitqueue_head(&found->flush_wait); spin_lock_init(&found->lock); found->flags = flags & (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM | @@ -2907,105 +2909,6 @@ static void check_force_delalloc(struct btrfs_space_info *meta_sinfo) meta_sinfo->force_delalloc = 0; } -struct async_flush { - struct btrfs_root *root; - struct btrfs_space_info *info; - struct btrfs_work work; -}; - -static noinline void flush_delalloc_async(struct btrfs_work *work) -{ - struct async_flush *async; - struct btrfs_root *root; - struct btrfs_space_info *info; - - async = container_of(work, struct async_flush, work); - root = async->root; - info = async->info; - - btrfs_start_delalloc_inodes(root, 0); - wake_up(&info->flush_wait); - btrfs_wait_ordered_extents(root, 0, 0); - - spin_lock(&info->lock); - info->flushing = 0; - spin_unlock(&info->lock); - wake_up(&info->flush_wait); - - kfree(async); -} - -static void wait_on_flush(struct btrfs_space_info *info) -{ - DEFINE_WAIT(wait); - u64 used; - - while (1) { - prepare_to_wait(&info->flush_wait, &wait, - TASK_UNINTERRUPTIBLE); - spin_lock(&info->lock); - if (!info->flushing) { - spin_unlock(&info->lock); - break; - } - - used = info->bytes_used + info->bytes_reserved + - info->bytes_pinned + info->bytes_readonly + - info->bytes_super + info->bytes_root + - info->bytes_may_use + info->bytes_delalloc; - if (used < info->total_bytes) { - spin_unlock(&info->lock); - break; - } - spin_unlock(&info->lock); - schedule(); - } - finish_wait(&info->flush_wait, &wait); -} - -static void flush_delalloc(struct btrfs_root *root, - struct btrfs_space_info *info) -{ - struct async_flush *async; - bool wait = false; - - spin_lock(&info->lock); - - if (!info->flushing) - info->flushing = 1; - else - wait = true; - - spin_unlock(&info->lock); - - if (wait) { - wait_on_flush(info); - return; - } - - async = kzalloc(sizeof(*async), GFP_NOFS); - if (!async) - goto flush; - - async->root = root; - async->info = info; - async->work.func = flush_delalloc_async; - - btrfs_queue_worker(&root->fs_info->enospc_workers, - &async->work); - wait_on_flush(info); - return; - -flush: - btrfs_start_delalloc_inodes(root, 0); - btrfs_wait_ordered_extents(root, 0, 0); - - spin_lock(&info->lock); - info->flushing = 0; - spin_unlock(&info->lock); - wake_up(&info->flush_wait); -} - /* * Reserve metadata space for delalloc. */ @@ -3058,7 +2961,7 @@ again: filemap_flush(inode->i_mapping); goto again; } else if (flushed == 3) { - flush_delalloc(root, meta_sinfo); + shrink_delalloc(NULL, root, meta_sinfo, num_bytes); goto again; } spin_lock(&meta_sinfo->lock); @@ -3171,7 +3074,7 @@ again: } if (retries == 2) { - flush_delalloc(root, meta_sinfo); + shrink_delalloc(NULL, root, meta_sinfo, num_bytes); goto again; } spin_lock(&meta_sinfo->lock); @@ -3197,7 +3100,7 @@ int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode, { struct btrfs_space_info *data_sinfo; u64 used; - int ret = 0, committed = 0, flushed = 0; + int ret = 0, committed = 0; /* make sure bytes are sectorsize aligned */ bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1); @@ -3217,13 +3120,6 @@ again: if (used + bytes > data_sinfo->total_bytes) { struct btrfs_trans_handle *trans; - if (!flushed) { - spin_unlock(&data_sinfo->lock); - flush_delalloc(root, data_sinfo); - flushed = 1; - goto again; - } - /* * if we don't have enough free bytes in this space then we need * to alloc a new chunk. @@ -3467,6 +3363,55 @@ static int maybe_allocate_chunk(struct btrfs_trans_handle *trans, return ret == 1 ? 1 : 0; } +/* + * shrink metadata reservation for delalloc + */ +static int shrink_delalloc(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_space_info *sinfo, u64 to_reclaim) +{ + u64 reserved; + u64 max_reclaim; + u64 reclaimed = 0; + int pause = 1; + int ret; + + spin_lock(&sinfo->lock); + reserved = sinfo->bytes_delalloc; + spin_unlock(&sinfo->lock); + + if (reserved == 0) + return 0; + + max_reclaim = min(reserved, to_reclaim); + + while (1) { + ret = btrfs_start_one_delalloc_inode(root, trans ? 1 : 0); + if (!ret) { + __set_current_state(TASK_INTERRUPTIBLE); + schedule_timeout(pause); + pause <<= 1; + if (pause > HZ / 10) + pause = HZ / 10; + } else { + pause = 1; + } + + spin_lock(&sinfo->lock); + if (reserved > sinfo->bytes_delalloc) + reclaimed = reserved - sinfo->bytes_delalloc; + reserved = sinfo->bytes_delalloc; + spin_unlock(&sinfo->lock); + + if (reserved == 0 || reclaimed >= max_reclaim) + break; + + if (trans && trans->transaction->blocked) + return -EAGAIN; + } + return reclaimed >= to_reclaim; +} + static int update_block_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, int alloc, diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 2bfdc64..d53cad1 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5611,6 +5611,38 @@ int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput) return 0; } +int btrfs_start_one_delalloc_inode(struct btrfs_root *root, int delay_iput) +{ + struct btrfs_inode *binode; + struct inode *inode = NULL; + + spin_lock(&root->fs_info->delalloc_lock); + while (!list_empty(&root->fs_info->delalloc_inodes)) { + binode = list_entry(root->fs_info->delalloc_inodes.next, + struct btrfs_inode, delalloc_inodes); + inode = igrab(&binode->vfs_inode); + if (inode) { + list_move_tail(&binode->delalloc_inodes, + &root->fs_info->delalloc_inodes); + break; + } + + list_del_init(&binode->delalloc_inodes); + cond_resched_lock(&root->fs_info->delalloc_lock); + } + spin_unlock(&root->fs_info->delalloc_lock); + + if (inode) { + write_inode_now(inode, 0); + if (delay_iput) + btrfs_add_delayed_iput(inode); + else + iput(inode); + return 1; + } + return 0; +} + static int btrfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) { -- 2.7.4