[PATCH 1/2] Btrfs: remove no longer used log_list member of struct btrfs_ordered_extent

[PATCH 1/2] Btrfs: remove no longer used log_list member of struct btrfs_ordered_extent

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

The 'log_list' member of an ordered extent was used keep track of which
ordered extents we needed to wait after logging metadata, but is not used
anymore since commit 5636cf7d6dc86f ("btrfs: remove the logged extents
infrastructure"), as we now always wait on ordered extent completion
before logging metadata. So just remove it since it's doing nothing and
making each ordered extent structure waste more memory (2 pointers).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/ordered-data.c | 2 --
 fs/btrfs/ordered-data.h | 3 ---
 2 files changed, 5 deletions(-)

diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index e13b3d28c063..73d5352c401b 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -197,7 +197,6 @@ static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 	INIT_LIST_HEAD(&entry->root_extent_list);
 	INIT_LIST_HEAD(&entry->work_list);
 	init_completion(&entry->completion);
-	INIT_LIST_HEAD(&entry->log_list);
 	INIT_LIST_HEAD(&entry->trans_list);
 
 	trace_btrfs_ordered_extent_add(inode, entry);
@@ -429,7 +428,6 @@ void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 	trace_btrfs_ordered_extent_put(entry->inode, entry);
 
 	if (refcount_dec_and_test(&entry->refs)) {
-		ASSERT(list_empty(&entry->log_list));
 		ASSERT(list_empty(&entry->trans_list));
 		ASSERT(list_empty(&entry->root_extent_list));
 		ASSERT(RB_EMPTY_NODE(&entry->rb_node));
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index c01c9698250b..35e81b80bd5d 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -101,9 +101,6 @@ struct btrfs_ordered_extent {
 	/* list of checksums for insertion when the extent io is done */
 	struct list_head list;
 
-	/* If we need to wait on this to be done */
-	struct list_head log_list;
-
 	/* If the transaction needs to wait on this ordered extent */
 	struct list_head trans_list;
 
-- 
2.26.2

Re: [PATCH 1/2] Btrfs: remove no longer used log_list member of struct btrfs_ordered_extent

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>

Re: [PATCH 1/2] Btrfs: remove no longer used log_list member of struct btrfs_ordered_extent

[David Sterba]

On Mon, Jun 15, 2020 at 10:36:48AM +0100, fdmanana@kernel.org wrote:
> From: Filipe Manana <fdmanana@suse.com>
> 
> The 'log_list' member of an ordered extent was used keep track of which
> ordered extents we needed to wait after logging metadata, but is not used
> anymore since commit 5636cf7d6dc86f ("btrfs: remove the logged extents
> infrastructure"), as we now always wait on ordered extent completion
> before logging metadata. So just remove it since it's doing nothing and
> making each ordered extent structure waste more memory (2 pointers).
> 
> Signed-off-by: Filipe Manana <fdmanana@suse.com>

Added to misc-next, thanks.