| Message ID | 20230515131757.60035-5-zhangpeng.00@bytedance.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Clean ups for maple tree | expand |
* Peng Zhang <zhangpeng.00@bytedance.com> [230515 09:18]: > Make the code for detecting spanning writes more concise. > > Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com> > --- > lib/maple_tree.c | 36 +++++++++--------------------------- > 1 file changed, 9 insertions(+), 27 deletions(-) > > diff --git a/lib/maple_tree.c b/lib/maple_tree.c > index 43a25d3042c1b..fbb6efc40e576 100644 > --- a/lib/maple_tree.c > +++ b/lib/maple_tree.c > @@ -3728,41 +3728,23 @@ static bool mas_is_span_wr(struct ma_wr_state *wr_mas) > { > unsigned long max; > unsigned long last = wr_mas->mas->last; > - unsigned long piv = wr_mas->r_max; > enum maple_type type = wr_mas->type; > void *entry = wr_mas->entry; > > - /* Contained in this pivot */ > - if (piv > last) I test this first since it is far more likely than the rest of the cases in this function. Most writes will land in a leaf node eventually, so this will be true most of the time. I'd like to keep it as a fast path. > + max = unlikely(ma_is_leaf(type)) ? wr_mas->mas->max : wr_mas->r_max; Please expand this to multiple lines. It is better to be more clear than compact lines of code. > + if (last < max) { > + /* Contained in this pivot or this leaf node */ > return false; > - > - max = wr_mas->mas->max; > - if (unlikely(ma_is_leaf(type))) { > - /* Fits in the node, but may span slots. */ > - if (last < max) > - return false; > - > - /* Writes to the end of the node but not null. */ > - if ((last == max) && entry) > - return false; > - > + } else if (last == max) { > /* > - * Writing ULONG_MAX is not a spanning write regardless of the > - * value being written as long as the range fits in the node. > + * The last entry of leaf node cannot be NULL unless it is the > + * rightmost node (writing ULONG_MAX), otherwise it spans slots. > + * If this is not leaf node, detect spanning store wr walk. > */ > - if ((last == ULONG_MAX) && (last == max)) > - return false; > - } else if (piv == last) { > - if (entry) > - return false; > - > - /* Detect spanning store wr walk */ > - if (last == ULONG_MAX) > + if (entry || last == ULONG_MAX) > return false; > } > - > - trace_ma_write(__func__, wr_mas->mas, piv, entry); > - > + trace_ma_write(__func__, wr_mas->mas, wr_mas->r_max, entry); > return true; > } > > -- > 2.20.1 >
diff --git a/lib/maple_tree.c b/lib/maple_tree.c index 43a25d3042c1b..fbb6efc40e576 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -3728,41 +3728,23 @@ static bool mas_is_span_wr(struct ma_wr_state *wr_mas) { unsigned long max; unsigned long last = wr_mas->mas->last; - unsigned long piv = wr_mas->r_max; enum maple_type type = wr_mas->type; void *entry = wr_mas->entry; - /* Contained in this pivot */ - if (piv > last) + max = unlikely(ma_is_leaf(type)) ? wr_mas->mas->max : wr_mas->r_max; + if (last < max) { + /* Contained in this pivot or this leaf node */ return false; - - max = wr_mas->mas->max; - if (unlikely(ma_is_leaf(type))) { - /* Fits in the node, but may span slots. */ - if (last < max) - return false; - - /* Writes to the end of the node but not null. */ - if ((last == max) && entry) - return false; - + } else if (last == max) { /* - * Writing ULONG_MAX is not a spanning write regardless of the - * value being written as long as the range fits in the node. + * The last entry of leaf node cannot be NULL unless it is the + * rightmost node (writing ULONG_MAX), otherwise it spans slots. + * If this is not leaf node, detect spanning store wr walk. */ - if ((last == ULONG_MAX) && (last == max)) - return false; - } else if (piv == last) { - if (entry) - return false; - - /* Detect spanning store wr walk */ - if (last == ULONG_MAX) + if (entry || last == ULONG_MAX) return false; } - - trace_ma_write(__func__, wr_mas->mas, piv, entry); - + trace_ma_write(__func__, wr_mas->mas, wr_mas->r_max, entry); return true; }
Make the code for detecting spanning writes more concise. Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com> --- lib/maple_tree.c | 36 +++++++++--------------------------- 1 file changed, 9 insertions(+), 27 deletions(-)