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 <quwenruo@xxxxxxxxxxxxxx>
> ---
> 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 majordomo@xxxxxxxxxxxxxxx
> 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 majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
