From: "Liam R. Howlett" Liam.Howlett@oracle.com
mainline inclusion from mainline-v6.8-rc1 commit e9c52d8940cbfd94b36035bbebce7f55954e7728 category: performance bugzilla: https://gitee.com/openeuler/kernel/issues/I9EHBO CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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When looking for the next entry, don't recalculate the node end as it is now tracked in the maple state.
Link: https://lkml.kernel.org/r/20231101171629.3612299-6-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Liam.Howlett@oracle.com Cc: Peng Zhang zhangpeng.00@bytedance.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: ZhangPeng zhangpeng362@huawei.com --- lib/maple_tree.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/lib/maple_tree.c b/lib/maple_tree.c index f0652557bd71..a118e584c64f 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -4539,6 +4539,7 @@ static inline int mas_next_node(struct ma_state *mas, struct maple_node *node, unsigned long min; unsigned long *pivots; struct maple_enode *enode; + struct maple_node *tmp; int level = 0; unsigned char node_end; enum maple_type mt; @@ -4591,6 +4592,10 @@ static inline int mas_next_node(struct ma_state *mas, struct maple_node *node, pivots = ma_pivots(node, mt);
mas->max = mas_safe_pivot(mas, pivots, mas->offset, mt); + tmp = mte_to_node(enode); + mt = mte_node_type(enode); + pivots = ma_pivots(tmp, mt); + mas->end = ma_data_end(tmp, mt, pivots, mas->max); if (unlikely(ma_dead_node(node))) return 1;
@@ -4625,7 +4630,6 @@ static void *mas_next_slot(struct ma_state *mas, unsigned long max, bool empty, unsigned long pivot; enum maple_type type; struct maple_node *node; - unsigned char data_end; unsigned long save_point = mas->last; void *entry;
@@ -4633,12 +4637,11 @@ static void *mas_next_slot(struct ma_state *mas, unsigned long max, bool empty, node = mas_mn(mas); type = mte_node_type(mas->node); pivots = ma_pivots(node, type); - data_end = ma_data_end(node, type, pivots, mas->max); if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) goto retry;
if (mas->max >= max) { - if (likely(mas->offset < data_end)) + if (likely(mas->offset < mas->end)) pivot = pivots[mas->offset]; else goto overflow; @@ -4650,11 +4653,11 @@ static void *mas_next_slot(struct ma_state *mas, unsigned long max, bool empty, goto overflow; }
- if (likely(mas->offset < data_end)) { + if (likely(mas->offset < mas->end)) { mas->index = pivots[mas->offset] + 1; again: mas->offset++; - if (likely(mas->offset < data_end)) + if (likely(mas->offset < mas->end)) mas->last = pivots[mas->offset]; else mas->last = mas->max; @@ -4691,7 +4694,6 @@ static void *mas_next_slot(struct ma_state *mas, unsigned long max, bool empty, goto overflow;
mas->index = mas->last + 1; - /* Node cannot end on NULL, so it's safe to short-cut here */ goto again; }