| Message ID | 20230522050656.96215-9-zhangpeng.00@bytedance.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Clean ups for maple tree | expand |
* Peng Zhang <zhangpeng.00@bytedance.com> [230522 01:07]: > The code of mas_wr_slot_store() is messy, make it clearer and concise, > and add comments. In addition, get whether the two gaps are empty to > avoid calling mas_update_gap() all the time. Try to concentrate on what you did in the log: Clean up the code and add comments, but the best part of this patch is the last "in addition" part, you should start your log with that. > > Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> > --- > lib/maple_tree.c | 53 +++++++++++++++++------------------------------- > 1 file changed, 19 insertions(+), 34 deletions(-) > > diff --git a/lib/maple_tree.c b/lib/maple_tree.c > index afbfdcdde5db..1fc872f7683c 100644 > --- a/lib/maple_tree.c > +++ b/lib/maple_tree.c > @@ -4203,49 +4203,34 @@ static inline bool mas_wr_node_store(struct ma_wr_state *wr_mas) > static inline bool mas_wr_slot_store(struct ma_wr_state *wr_mas) > { > struct ma_state *mas = wr_mas->mas; > - unsigned long lmax; /* Logical max. */ > unsigned char offset = mas->offset; > + bool gap = false; > > - if ((wr_mas->r_max > mas->last) && ((wr_mas->r_min != mas->index) || > - (offset != wr_mas->node_end))) > + if (wr_mas->offset_end - offset != 1) > return false; > > - if (offset == wr_mas->node_end - 1) > - lmax = mas->max; > - else > - lmax = wr_mas->pivots[offset + 1]; > - > - /* going to overwrite too many slots. */ > - if (lmax < mas->last) > - return false; > - > - if (wr_mas->r_min == mas->index) { > - /* overwriting two or more ranges with one. */ > - if (lmax == mas->last) > - return false; > + gap |= !mt_slot_locked(mas->tree, wr_mas->slots, offset); > + gap |= !mt_slot_locked(mas->tree, wr_mas->slots, offset + 1); > > - /* Overwriting all of offset and a portion of offset + 1. */ > + if (mas->index == wr_mas->r_min) { > + /* Overwriting the range and over a part of the next range. */ > rcu_assign_pointer(wr_mas->slots[offset], wr_mas->entry); > wr_mas->pivots[offset] = mas->last; > - goto done; > + } else { > + /* Overwriting a part of the range and over the next range */ > + rcu_assign_pointer(wr_mas->slots[offset + 1], wr_mas->entry); > + wr_mas->pivots[offset] = mas->index - 1; > + mas->offset++; /* Keep mas accurate. */ > } > > - /* Doesn't end on the next range end. */ > - if (lmax != mas->last) > - return false; > - > - /* Overwriting a portion of offset and all of offset + 1 */ > - if ((offset + 1 < mt_pivots[wr_mas->type]) && > - (wr_mas->entry || wr_mas->pivots[offset + 1])) > - wr_mas->pivots[offset + 1] = mas->last; > - > - rcu_assign_pointer(wr_mas->slots[offset + 1], wr_mas->entry); > - wr_mas->pivots[offset] = mas->index - 1; > - mas->offset++; /* Keep mas accurate. */ > - > -done: > trace_ma_write(__func__, mas, 0, wr_mas->entry); > - mas_update_gap(mas); > + /* > + * Only update gap when the new entry is empty or there is an empty > + * entry in the original two ranges. > + */ > + if (!wr_mas->entry || gap) > + mas_update_gap(mas); > + > return true; > } > > @@ -4392,7 +4377,7 @@ static inline void mas_wr_modify(struct ma_wr_state *wr_mas) > if (new_end == wr_mas->node_end + 1 && mas_wr_append(wr_mas)) > return; > > - if ((wr_mas->offset_end - mas->offset <= 1) && mas_wr_slot_store(wr_mas)) > + if (new_end == wr_mas->node_end && mas_wr_slot_store(wr_mas)) > return; > else if (mas_wr_node_store(wr_mas)) > return; > -- > 2.20.1 >
diff --git a/lib/maple_tree.c b/lib/maple_tree.c index afbfdcdde5db..1fc872f7683c 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -4203,49 +4203,34 @@ static inline bool mas_wr_node_store(struct ma_wr_state *wr_mas) static inline bool mas_wr_slot_store(struct ma_wr_state *wr_mas) { struct ma_state *mas = wr_mas->mas; - unsigned long lmax; /* Logical max. */ unsigned char offset = mas->offset; + bool gap = false; - if ((wr_mas->r_max > mas->last) && ((wr_mas->r_min != mas->index) || - (offset != wr_mas->node_end))) + if (wr_mas->offset_end - offset != 1) return false; - if (offset == wr_mas->node_end - 1) - lmax = mas->max; - else - lmax = wr_mas->pivots[offset + 1]; - - /* going to overwrite too many slots. */ - if (lmax < mas->last) - return false; - - if (wr_mas->r_min == mas->index) { - /* overwriting two or more ranges with one. */ - if (lmax == mas->last) - return false; + gap |= !mt_slot_locked(mas->tree, wr_mas->slots, offset); + gap |= !mt_slot_locked(mas->tree, wr_mas->slots, offset + 1); - /* Overwriting all of offset and a portion of offset + 1. */ + if (mas->index == wr_mas->r_min) { + /* Overwriting the range and over a part of the next range. */ rcu_assign_pointer(wr_mas->slots[offset], wr_mas->entry); wr_mas->pivots[offset] = mas->last; - goto done; + } else { + /* Overwriting a part of the range and over the next range */ + rcu_assign_pointer(wr_mas->slots[offset + 1], wr_mas->entry); + wr_mas->pivots[offset] = mas->index - 1; + mas->offset++; /* Keep mas accurate. */ } - /* Doesn't end on the next range end. */ - if (lmax != mas->last) - return false; - - /* Overwriting a portion of offset and all of offset + 1 */ - if ((offset + 1 < mt_pivots[wr_mas->type]) && - (wr_mas->entry || wr_mas->pivots[offset + 1])) - wr_mas->pivots[offset + 1] = mas->last; - - rcu_assign_pointer(wr_mas->slots[offset + 1], wr_mas->entry); - wr_mas->pivots[offset] = mas->index - 1; - mas->offset++; /* Keep mas accurate. */ - -done: trace_ma_write(__func__, mas, 0, wr_mas->entry); - mas_update_gap(mas); + /* + * Only update gap when the new entry is empty or there is an empty + * entry in the original two ranges. + */ + if (!wr_mas->entry || gap) + mas_update_gap(mas); + return true; } @@ -4392,7 +4377,7 @@ static inline void mas_wr_modify(struct ma_wr_state *wr_mas) if (new_end == wr_mas->node_end + 1 && mas_wr_append(wr_mas)) return; - if ((wr_mas->offset_end - mas->offset <= 1) && mas_wr_slot_store(wr_mas)) + if (new_end == wr_mas->node_end && mas_wr_slot_store(wr_mas)) return; else if (mas_wr_node_store(wr_mas)) return;
The code of mas_wr_slot_store() is messy, make it clearer and concise, and add comments. In addition, get whether the two gaps are empty to avoid calling mas_update_gap() all the time. Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com> --- lib/maple_tree.c | 53 +++++++++++++++++------------------------------- 1 file changed, 19 insertions(+), 34 deletions(-)