On Thu, Mar 12, 2015 at 04:33:27PM +0800, Qu Wenruo wrote:
> Use inline functions to do such things, to improve readability.

This has actually hiden informations behind the helper function and
old_refcnt and new_refcnt can explain themselves, I don't see any benefit.

Thanks,

-liubo
> 
> Signed-off-by: Qu Wenruo <[email protected]>
> ---
>  fs/btrfs/qgroup.c | 102 
> ++++++++++++++++++++++++++++++++++--------------------
>  1 file changed, 65 insertions(+), 37 deletions(-)
> 
> diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
> index 97159a8..3f2a1e7 100644
> --- a/fs/btrfs/qgroup.c
> +++ b/fs/btrfs/qgroup.c
> @@ -84,11 +84,58 @@ struct btrfs_qgroup {
>  
>       /*
>        * temp variables for accounting operations
> +      * Refer to qgroup_shared_accouting() for details.
>        */
>       u64 old_refcnt;
>       u64 new_refcnt;
>  };
>  
> +static void update_qg_refcnt(struct btrfs_qgroup *qg, u64 seq, int mod,
> +                          int update_old)
> +{
> +     if (update_old) {
> +             if (qg->old_refcnt < seq)
> +                     qg->old_refcnt = seq;
> +             qg->old_refcnt += mod;
> +     } else {
> +             if (qg->new_refcnt < seq)
> +                     qg->new_refcnt = seq;
> +             qg->new_refcnt += mod;
> +     }
> +}
> +
> +static void update_qg_old_refcnt(struct btrfs_qgroup *qg, u64 seq, int mod)
> +{
> +     update_qg_refcnt(qg, seq, mod, 1);
> +}
> +
> +static void update_qg_new_refcnt(struct btrfs_qgroup *qg, u64 seq, int mod)
> +{
> +     update_qg_refcnt(qg, seq, mod, 0);
> +}
> +
> +static inline u64 get_qg_refcnt(struct btrfs_qgroup *qg, u64 seq, int 
> get_old)
> +{
> +     if (get_old) {
> +             if (qg->old_refcnt < seq)
> +                     return 0;
> +             return qg->old_refcnt - seq;
> +     }
> +     if (qg->new_refcnt < seq)
> +             return 0;
> +     return qg->new_refcnt - seq;
> +}
> +
> +static inline u64 get_qg_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
> +{
> +     return get_qg_refcnt(qg, seq, 1);
> +}
> +
> +static inline u64 get_qg_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
> +{
> +     return get_qg_refcnt(qg, seq, 0);
> +}
> +
>  /*
>   * glue structure to represent the relations between qgroups.
>   */
> @@ -1497,6 +1544,7 @@ static int qgroup_calc_old_refcnt(struct btrfs_fs_info 
> *fs_info,
>               ULIST_ITER_INIT(&tmp_uiter);
>               while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
>                       struct btrfs_qgroup_list *glist;
> +                     int mod;
>  
>                       qg = u64_to_ptr(tmp_unode->aux);
>                       /*
> @@ -1508,20 +1556,15 @@ static int qgroup_calc_old_refcnt(struct 
> btrfs_fs_info *fs_info,
>                        * upper level qgroups in order to determine exclusive
>                        * counts.
>                        *
> -                      * For rescan we want to set old_refcnt to seq so our
> -                      * exclusive calculations end up correct.
> +                      * For rescan none of the extent is recorded before so
> +                      * we just don't add old_refcnt.
>                        */
>                       if (rescan)
> -                             qg->old_refcnt = seq;
> -                     else if (qg->old_refcnt < seq)
> -                             qg->old_refcnt = seq + 1;
> +                             mod = 0;
>                       else
> -                             qg->old_refcnt++;
> -
> -                     if (qg->new_refcnt < seq)
> -                             qg->new_refcnt = seq + 1;
> -                     else
> -                             qg->new_refcnt++;
> +                             mod = 1;
> +                     update_qg_old_refcnt(qg, seq, mod);
> +                     update_qg_new_refcnt(qg, seq, 1);
>                       list_for_each_entry(glist, &qg->groups, next_group) {
>                               ret = ulist_add(qgroups, glist->group->qgroupid,
>                                               ptr_to_u64(glist->group),
> @@ -1619,10 +1662,8 @@ next:
>                       qg->old_refcnt = seq + 1;
>               else
>                       qg->old_refcnt++;
> -             if (qg->new_refcnt < seq)
> -                     qg->new_refcnt = seq + 1;
> -             else
> -                     qg->new_refcnt++;
> +             update_qg_old_refcnt(qg, seq, 1);
> +             update_qg_new_refcnt(qg, seq, 1);
>               list_for_each_entry(glist, &qg->groups, next_group) {
>                       ret = ulist_add(qgroups, glist->group->qgroupid,
>                                       ptr_to_u64(glist->group), GFP_ATOMIC);
> @@ -1663,17 +1704,10 @@ static int qgroup_calc_new_refcnt(struct 
> btrfs_fs_info *fs_info,
>               struct btrfs_qgroup_list *glist;
>  
>               qg = u64_to_ptr(unode->aux);
> -             if (oper->type == BTRFS_QGROUP_OPER_ADD_SHARED) {
> -                     if (qg->new_refcnt < seq)
> -                             qg->new_refcnt = seq + 1;
> -                     else
> -                             qg->new_refcnt++;
> -             } else {
> -                     if (qg->old_refcnt < seq)
> -                             qg->old_refcnt = seq + 1;
> -                     else
> -                             qg->old_refcnt++;
> -             }
> +             if (oper->type == BTRFS_QGROUP_OPER_ADD_SHARED)
> +                     update_qg_new_refcnt(qg, seq, 1);
> +             else
> +                     update_qg_old_refcnt(qg, seq, 1);
>               list_for_each_entry(glist, &qg->groups, next_group) {
>                       ret = ulist_add(tmp, glist->group->qgroupid,
>                                       ptr_to_u64(glist->group), GFP_ATOMIC);
> @@ -1706,11 +1740,14 @@ static int qgroup_adjust_counters(struct 
> btrfs_fs_info *fs_info,
>               bool dirty = false;
>  
>               qg = u64_to_ptr(unode->aux);
> +             cur_old_count = get_qg_old_refcnt(qg, seq);
> +             cur_new_count = get_qg_new_refcnt(qg, seq);
> +
>               /*
>                * Wasn't referenced before but is now, add to the reference
>                * counters.
>                */
> -             if (qg->old_refcnt <= seq && qg->new_refcnt > seq) {
> +             if (cur_old_count == 0 && cur_new_count > 0) {
>                       qg->rfer += num_bytes;
>                       qg->rfer_cmpr += num_bytes;
>                       dirty = true;
> @@ -1720,21 +1757,12 @@ static int qgroup_adjust_counters(struct 
> btrfs_fs_info *fs_info,
>                * Was referenced before but isn't now, subtract from the
>                * reference counters.
>                */
> -             if (qg->old_refcnt > seq && qg->new_refcnt <= seq) {
> +             if (cur_old_count > 0 && cur_new_count == 0) {
>                       qg->rfer -= num_bytes;
>                       qg->rfer_cmpr -= num_bytes;
>                       dirty = true;
>               }
>  
> -             if (qg->old_refcnt < seq)
> -                     cur_old_count = 0;
> -             else
> -                     cur_old_count = qg->old_refcnt - seq;
> -             if (qg->new_refcnt < seq)
> -                     cur_new_count = 0;
> -             else
> -                     cur_new_count = qg->new_refcnt - seq;
> -
>               /*
>                * If our refcount was the same as the roots previously but our
>                * new count isn't the same as the number of roots now then we
> -- 
> 2.3.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to [email protected]
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to