On 2018/9/26 下午10:40, David Sterba wrote:
> On Tue, Sep 11, 2018 at 01:38:17PM +0800, Qu Wenruo wrote:
>> For btrfs_add_delayed_tree_ref(), its ref_root parameter can be
>> different from its real root.
>> This is pretty common for reloc tree, in that case @ref_root is passed
>> as the original tree owner (source file tree).
>>
>> However btrfs_add_delayed_tree_ref() uses @ref_root to determine whether
>> we should do heavy qgroup tracing for it, so for balance this could
>> cause a lot of unnecessary extent tracing.
>>
>> This patch will introduce a parameter, @root for qgroup code to
>> determine whether we really need to do the heavy-lifting tracing work.
>>
>> This patch would reduce the qgroup dirty extent number from 'number of
>> extents being relocated' to 0 for the transaction before real tree swap.
>>
>> Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
>> ---
>> fs/btrfs/delayed-ref.c | 5 +++--
>> fs/btrfs/delayed-ref.h | 1 +
>> fs/btrfs/extent-tree.c | 17 ++++++++++-------
>> 3 files changed, 14 insertions(+), 9 deletions(-)
>>
>> diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
>> index 62ff545ba1f7..7f681dd36e7f 100644
>> --- a/fs/btrfs/delayed-ref.c
>> +++ b/fs/btrfs/delayed-ref.c
>> @@ -710,8 +710,9 @@ static void init_delayed_ref_common(struct btrfs_fs_info *fs_info,
>> * transaction commits.
>> */
>> int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
>> + struct btrfs_root *root,
>> u64 bytenr, u64 num_bytes, u64 parent,
>> - u64 ref_root, int level, int action,
>> + u64 ref_root, int level, int action,
>
> Unrelated change
Will avoid it in next update.
>
>> struct btrfs_delayed_extent_op *extent_op,
>> int *old_ref_mod, int *new_ref_mod)
>> {
>> @@ -737,7 +738,7 @@ int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
>> }
>>
>> if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) &&
>> - is_fstree(ref_root)) {
>> + is_fstree(root->root_key.objectid)) {
>> record = kmalloc(sizeof(*record), GFP_NOFS);
>> if (!record) {
>> kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
>> diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
>> index d9f2a4ebd5db..a51560a3cb66 100644
>> --- a/fs/btrfs/delayed-ref.h
>> +++ b/fs/btrfs/delayed-ref.h
>> @@ -235,6 +235,7 @@ static inline void btrfs_put_delayed_ref_head(struct btrfs_delayed_ref_head *hea
>> }
>>
>> int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
>> + struct btrfs_root *root,
>> u64 bytenr, u64 num_bytes, u64 parent,
>> u64 ref_root, int level, int action,
>> struct btrfs_delayed_extent_op *extent_op,
>> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
>> index 4588153f414c..7a3c650b11f8 100644
>> --- a/fs/btrfs/extent-tree.c
>> +++ b/fs/btrfs/extent-tree.c
>> @@ -2040,9 +2040,10 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
>> owner, offset, BTRFS_ADD_DELAYED_REF);
>>
>> if (owner < BTRFS_FIRST_FREE_OBJECTID) {
>> - ret = btrfs_add_delayed_tree_ref(trans, bytenr,
>> + ret = btrfs_add_delayed_tree_ref(trans, root, bytenr,
>> num_bytes, parent,
>> - root_objectid, (int)owner,
>> + root_objectid,
>> + (int)owner,
>
> Here as well and a few more below. The (int) typecast is actually a bug
> as it trims the owner to just 32bits, so if you want to update the
> formatting, please send a separate patch.
Will avoid the unrelated change in next update.
But for the "bug" part, it's a mess.
Since owner is smaller than BTRFS_FIRST_FREE_OBJECTID, truncating to
32bits is in fact completely OK.
However the declaration of btrfs_add_delayed_tree_ref() says that
parameter is in fact @level.
On the other hand, ref->level is passed to __btrfs_inc_extent_ref() as
@onwer (and u64) again, so it's not causing problem (or we're already
screwed up badly).
The naming and forced convert is really a mess here though.
I'll just keep that mess as is and don't touch it for the patchset.
Thanks,
Qu
>
>> BTRFS_ADD_DELAYED_REF, NULL,
>> &old_ref_mod, &new_ref_mod);
>> } else {
>> @@ -6993,7 +6994,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
>> root->root_key.objectid,
>> btrfs_header_level(buf), 0,
>> BTRFS_DROP_DELAYED_REF);
>> - ret = btrfs_add_delayed_tree_ref(trans, buf->start,
>> + ret = btrfs_add_delayed_tree_ref(trans, root, buf->start,
>> buf->len, parent,
>> root->root_key.objectid,
>> btrfs_header_level(buf),
>> @@ -7072,9 +7073,10 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
>> old_ref_mod = new_ref_mod = 0;
>> ret = 0;
>> } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
>> - ret = btrfs_add_delayed_tree_ref(trans, bytenr,
>> + ret = btrfs_add_delayed_tree_ref(trans, root, bytenr,
>> num_bytes, parent,
>> - root_objectid, (int)owner,
>> + root_objectid,
>> + (int)owner,
>> BTRFS_DROP_DELAYED_REF, NULL,
>> &old_ref_mod, &new_ref_mod);
>> } else {
>> @@ -8293,9 +8295,10 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
>> btrfs_ref_tree_mod(root, ins.objectid, ins.offset, parent,
>> root_objectid, level, 0,
>> BTRFS_ADD_DELAYED_EXTENT);
>> - ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
>> + ret = btrfs_add_delayed_tree_ref(trans, root, ins.objectid,
>> ins.offset, parent,
>> - root_objectid, level,
>> + root_objectid,
>> + level,
>> BTRFS_ADD_DELAYED_EXTENT,
>> extent_op, NULL, NULL);
>> if (ret)
>> --
>> 2.18.0
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