On Mon, Jan 20, 2020 at 04:09:16PM +0200, Nikolay Borisov wrote:
> In preparation to making pinned extents per-transaction ensure that
> log such extents are always excluded from caching. To achieve this in
> addition to marking them via btrfs_pin_extent_for_log_replay they also
> need to be marked with btrfs_add_excluded_extent to prevent log tree
> extent buffer being loaded by the free space caching thread. That's
> required since log treeblocks are not recorded in the extent tree, hence
> they always look free.
>
> Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
> ---
> fs/btrfs/extent-tree.c | 8 ++++++++
> fs/btrfs/tree-log.c | 2 +-
> 2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
> index 7dcf9217a622..d680f2ac336b 100644
> --- a/fs/btrfs/extent-tree.c
> +++ b/fs/btrfs/extent-tree.c
> @@ -2634,6 +2634,8 @@ int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans,
> struct btrfs_block_group *cache;
> int ret;
>
> + btrfs_add_excluded_extent(trans->fs_info, bytenr, num_bytes);
Again lack of error handling, I thought that untangling and cleaning up
the extent pinning was motivated to actually handle the errors.
> +
> cache = btrfs_lookup_block_group(trans->fs_info, bytenr);
> if (!cache)
> return -EINVAL;
> @@ -2920,6 +2922,12 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans)
> mutex_unlock(&fs_info->unused_bg_unpin_mutex);
> break;
> }
> + if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) {
> + clear_extent_bits(&fs_info->freed_extents[0], start,
> + end, EXTENT_UPTODATE);
> + clear_extent_bits(&fs_info->freed_extents[1], start,
> + end, EXTENT_UPTODATE);
> + }
>
> if (btrfs_test_opt(fs_info, DISCARD_SYNC))
> ret = btrfs_discard_extent(fs_info, start,
> diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
> index b535d409a728..f89de24838d5 100644
> --- a/fs/btrfs/tree-log.c
> +++ b/fs/btrfs/tree-log.c
> @@ -2994,7 +2994,7 @@ static inline void btrfs_remove_log_ctx(struct btrfs_root *root,
> mutex_unlock(&root->log_mutex);
> }
>
> -/*
> +/*
> * Invoked in log mutex context, or be sure there is no other task which
> * can access the list.
> */
> --
> 2.17.1
