btrfs_delayed_extent_op can be packed in a better way, it's 40 bytes now
and has 8 unused bytes. Reducing the level type to u8 makes it possible
to squeeze it to the padding byte after key. The bitfields were switched
to bool as there's space to store the full byte without increasing the
whole structure, besides that the generated assembly is smaller.
struct btrfs_delayed_extent_op {
struct btrfs_disk_key key; /* 0 17 */
u8 level; /* 17 1 */
bool update_key; /* 18 1 */
bool update_flags; /* 19 1 */
bool is_data; /* 20 1 */
/* XXX 3 bytes hole, try to pack */
u64 flags_to_set; /* 24 8 */
/* size: 32, cachelines: 1, members: 6 */
/* sum members: 29, holes: 1, sum holes: 3 */
/* last cacheline: 32 bytes */
};
The final size is 32 bytes which gives +26 object per slab page.
text data bss dec hex filename
938811 43670 23144 1005625 f5839 fs/btrfs/btrfs.ko.before
938747 43670 23144 1005561 f57f9 fs/btrfs/btrfs.ko.after
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
---
fs/btrfs/delayed-ref.c | 4 ++--
fs/btrfs/delayed-ref.h | 8 ++++----
fs/btrfs/extent-tree.c | 15 ++++++---------
fs/btrfs/extent-tree.h | 0
4 files changed, 12 insertions(+), 15 deletions(-)
delete mode 100644 fs/btrfs/extent-tree.h
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index e06dd75ad13f..914ac13bd92f 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -493,12 +493,12 @@ update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs,
memcpy(&existing_ref->extent_op->key,
&ref->extent_op->key,
sizeof(ref->extent_op->key));
- existing_ref->extent_op->update_key = 1;
+ existing_ref->extent_op->update_key = true;
}
if (ref->extent_op->update_flags) {
existing_ref->extent_op->flags_to_set |=
ref->extent_op->flags_to_set;
- existing_ref->extent_op->update_flags = 1;
+ existing_ref->extent_op->update_flags = true;
}
btrfs_free_delayed_extent_op(ref->extent_op);
}
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
index 00ed02cbf3e9..c24b653c7343 100644
--- a/fs/btrfs/delayed-ref.h
+++ b/fs/btrfs/delayed-ref.h
@@ -75,11 +75,11 @@ struct btrfs_delayed_ref_node {
struct btrfs_delayed_extent_op {
struct btrfs_disk_key key;
+ u8 level;
+ bool update_key;
+ bool update_flags;
+ bool is_data;
u64 flags_to_set;
- int level;
- unsigned int update_key:1;
- unsigned int update_flags:1;
- unsigned int is_data:1;
};
/*
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index acf3ed11cfb6..5c542f10c9b6 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2988,9 +2988,9 @@ int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
return -ENOMEM;
extent_op->flags_to_set = flags;
- extent_op->update_flags = 1;
- extent_op->update_key = 0;
- extent_op->is_data = is_data ? 1 : 0;
+ extent_op->update_flags = true;
+ extent_op->update_key = false;
+ extent_op->is_data = is_data ? true : false;
extent_op->level = level;
ret = btrfs_add_delayed_extent_op(root->fs_info, trans, bytenr,
@@ -7977,12 +7977,9 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
else
memset(&extent_op->key, 0, sizeof(extent_op->key));
extent_op->flags_to_set = flags;
- if (skinny_metadata)
- extent_op->update_key = 0;
- else
- extent_op->update_key = 1;
- extent_op->update_flags = 1;
- extent_op->is_data = 0;
+ extent_op->update_key = skinny_metadata ? false : true;
+ extent_op->update_flags = true;
+ extent_op->is_data = false;
extent_op->level = level;
ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
diff --git a/fs/btrfs/extent-tree.h b/fs/btrfs/extent-tree.h
deleted file mode 100644
index e69de29bb2d1..000000000000
--
1.8.4.5
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