On Fri, Feb 5, 2021 at 9:15 AM Naohiro Aota <naohiro.a...@wdc.com> wrote: > > David, could you fold the below incremental diff to this patch? Or, I > can send a full replacement patch. > > diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c > index 8be3164d4c5d..4e72794342c0 100644 > --- a/fs/btrfs/tree-log.c > +++ b/fs/btrfs/tree-log.c > @@ -143,6 +143,7 @@ static int start_log_trans(struct btrfs_trans_handle > *trans, > struct btrfs_root *tree_root = fs_info->tree_root; > const bool zoned = btrfs_is_zoned(fs_info); > int ret = 0; > + bool created = false; > > /* > * First check if the log root tree was already created. If not, > create > @@ -152,8 +153,10 @@ static int start_log_trans(struct btrfs_trans_handle > *trans, > mutex_lock(&tree_root->log_mutex); > if (!fs_info->log_root_tree) { > ret = btrfs_init_log_root_tree(trans, fs_info); > - if (!ret) > + if (!ret) { > set_bit(BTRFS_ROOT_HAS_LOG_TREE, > &tree_root->state); > + created = true; > + } > } > mutex_unlock(&tree_root->log_mutex); > if (ret) > @@ -183,16 +186,16 @@ static int start_log_trans(struct btrfs_trans_handle > *trans, > set_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); > } > } else { > - if (zoned) { > - mutex_lock(&fs_info->tree_log_mutex); > - if (fs_info->log_root_tree) > - ret = -EAGAIN; > - else > - ret = btrfs_init_log_root_tree(trans, > fs_info); > - mutex_unlock(&fs_info->tree_log_mutex); > - } > - if (ret) > + /* > + * This means fs_info->log_root_tree was already created > + * for some other FS trees. Do the full commit not to mix > + * nodes from multiple log transactions to do sequential > + * writing. > + */ > + if (zoned && !created) { > + ret = -EAGAIN; > goto out; > + } > > ret = btrfs_add_log_tree(trans, root); > if (ret) >
Ok, with this, it looks good to me and you can have, Reviewed-by: Filipe Manana <fdman...@suse.com> Thanks. > > On Thu, Feb 04, 2021 at 07:22:19PM +0900, Naohiro Aota wrote: > > This is the 2/3 patch to enable tree-log on zoned filesystems. > > > > Since we can start more than one log transactions per subvolume > > simultaneously, nodes from multiple transactions can be allocated > > interleaved. Such mixed allocation results in non-sequential writes at the > > time of a log transaction commit. The nodes of the global log root tree > > (fs_info->log_root_tree), also have the same problem with mixed > > allocation. > > > > Serializes log transactions by waiting for a committing transaction when > > someone tries to start a new transaction, to avoid the mixed allocation > > problem. We must also wait for running log transactions from another > > subvolume, but there is no easy way to detect which subvolume root is > > running a log transaction. So, this patch forbids starting a new log > > transaction when other subvolumes already allocated the global log root > > tree. > > > > Cc: Filipe Manana <fdman...@gmail.com> > > Reviewed-by: Josef Bacik <jo...@toxicpanda.com> > > Signed-off-by: Naohiro Aota <naohiro.a...@wdc.com> > > --- > > fs/btrfs/tree-log.c | 29 +++++++++++++++++++++++++++++ > > 1 file changed, 29 insertions(+) > > > > diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c > > index c02eeeac439c..8be3164d4c5d 100644 > > --- a/fs/btrfs/tree-log.c > > +++ b/fs/btrfs/tree-log.c > > @@ -105,6 +105,7 @@ static noinline int replay_dir_deletes(struct > > btrfs_trans_handle *trans, > > struct btrfs_root *log, > > struct btrfs_path *path, > > u64 dirid, int del_all); > > +static void wait_log_commit(struct btrfs_root *root, int transid); > > > > /* > > * tree logging is a special write ahead log used to make sure that > > @@ -140,6 +141,7 @@ static int start_log_trans(struct btrfs_trans_handle > > *trans, > > { > > struct btrfs_fs_info *fs_info = root->fs_info; > > struct btrfs_root *tree_root = fs_info->tree_root; > > + const bool zoned = btrfs_is_zoned(fs_info); > > int ret = 0; > > > > /* > > @@ -160,12 +162,20 @@ static int start_log_trans(struct btrfs_trans_handle > > *trans, > > > > mutex_lock(&root->log_mutex); > > > > +again: > > if (root->log_root) { > > + int index = (root->log_transid + 1) % 2; > > + > > if (btrfs_need_log_full_commit(trans)) { > > ret = -EAGAIN; > > goto out; > > } > > > > + if (zoned && atomic_read(&root->log_commit[index])) { > > + wait_log_commit(root, root->log_transid - 1); > > + goto again; > > + } > > + > > if (!root->log_start_pid) { > > clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); > > root->log_start_pid = current->pid; > > @@ -173,6 +183,17 @@ static int start_log_trans(struct btrfs_trans_handle > > *trans, > > set_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); > > } > > } else { > > + if (zoned) { > > + mutex_lock(&fs_info->tree_log_mutex); > > + if (fs_info->log_root_tree) > > + ret = -EAGAIN; > > + else > > + ret = btrfs_init_log_root_tree(trans, > > fs_info); > > + mutex_unlock(&fs_info->tree_log_mutex); > > + } > > + if (ret) > > + goto out; > > + > > ret = btrfs_add_log_tree(trans, root); > > if (ret) > > goto out; > > @@ -201,14 +222,22 @@ static int start_log_trans(struct btrfs_trans_handle > > *trans, > > */ > > static int join_running_log_trans(struct btrfs_root *root) > > { > > + const bool zoned = btrfs_is_zoned(root->fs_info); > > int ret = -ENOENT; > > > > if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE, &root->state)) > > return ret; > > > > mutex_lock(&root->log_mutex); > > +again: > > if (root->log_root) { > > + int index = (root->log_transid + 1) % 2; > > + > > ret = 0; > > + if (zoned && atomic_read(&root->log_commit[index])) { > > + wait_log_commit(root, root->log_transid - 1); > > + goto again; > > + } > > atomic_inc(&root->log_writers); > > } > > mutex_unlock(&root->log_mutex); > > -- > > 2.30.0 > > -- Filipe David Manana, “Whether you think you can, or you think you can't — you're right.”