From c58b9bf4c367ae2f4feb46c63b2bbce30e835808 Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" Date: Fri, 21 Feb 2020 23:00:32 -0500 Subject: [PATCH] maple_tree: Fix mas_prev issue with parent slot & loop at root. parent slots were not being set correctly for the first ascend. This caused data to be skipped. There was also an infinite loop if this was the first entry in a deep tree. Signed-off-by: Liam R. Howlett --- lib/maple_tree.c | 10 +- lib/test_maple_tree.c | 290 +++++++++++++++++++++++++++++++++++++++++- 2 files changed, 294 insertions(+), 6 deletions(-) diff --git a/lib/maple_tree.c b/lib/maple_tree.c index 37b452600181..69c63082c7d3 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -2814,16 +2814,15 @@ static inline void mas_prev_node(struct ma_state *mas, unsigned long limit) int slot; unsigned long start_piv; - slot = mas_get_slot(mas); start_piv = mas_get_safe_pivot(mas, slot); restart_prev_node: level = 0; - slot = mas_get_slot(mas); if (mte_is_root(mas->node) || mas->node == MAS_NONE) goto no_entry; while (1) { unsigned long min; + slot = mte_parent_slot(mas->node); mas_ascend(mas); level++; @@ -2877,8 +2876,6 @@ restart_prev_node: ascend: if (mte_is_root(mas->node)) goto no_entry; - - slot = mte_parent_slot(mas->node); } no_entry: @@ -3244,6 +3241,9 @@ void *mas_prev(struct ma_state *mas, unsigned long min) do { entry = _mas_prev(mas, min); + if (!mas_searchable(mas)) + break; + } while (!entry || mt_will_coalesce(entry)); return entry; @@ -3982,7 +3982,7 @@ static inline int mas_safe_slot(struct ma_state *mas, int *slot, return false; entry = mte_get_rcu_slot(mas->node, (*slot) + delta); - if (!mt_is_empty(entry)) + if (!mt_is_empty(entry) && !xa_is_retry(entry)) return true; *slot += delta; } diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c index 6daa7a74ec99..c8a81ef5a28b 100644 --- a/lib/test_maple_tree.c +++ b/lib/test_maple_tree.c @@ -10331,6 +10331,275 @@ STORE, 140222968504320, 140222970597375, STORE, 140222970597376, 140222970605567, ERASE, 140222970597376, 140222970605567, STORE, 140222970597376, 140222970605567, + }; + unsigned long set19[] = { +STORE, 140737488347136, 140737488351231, +STORE, 140725182459904, 140737488351231, +SNULL, 140725182463999, 140737488351231, +STORE, 140725182459904, 140725182463999, +STORE, 140725182328832, 140725182463999, +STORE, 94730166636544, 94730166763519, +SNULL, 94730166747135, 94730166763519, +STORE, 94730166636544, 94730166747135, +STORE, 94730166747136, 94730166763519, +ERASE, 94730166747136, 94730166763519, +STORE, 94730166751232, 94730166763519, +STORE, 140656834555904, 140656836808703, +SNULL, 140656834699263, 140656836808703, +STORE, 140656834555904, 140656834699263, +STORE, 140656834699264, 140656836808703, +ERASE, 140656834699264, 140656836808703, +STORE, 140656836796416, 140656836804607, +STORE, 140656836804608, 140656836808703, +STORE, 140725183389696, 140725183393791, +STORE, 140725183377408, 140725183389695, +STORE, 140656836788224, 140656836796415, +STORE, 140656832331776, 140656834555903, +SNULL, 140656833982463, 140656834555903, +STORE, 140656832331776, 140656833982463, +STORE, 140656833982464, 140656834555903, +SNULL, 140656833982464, 140656834551807, +STORE, 140656834551808, 140656834555903, +STORE, 140656833982464, 140656834551807, +ERASE, 140656833982464, 140656834551807, +STORE, 140656833982464, 140656834551807, +ERASE, 140656834551808, 140656834555903, +STORE, 140656834551808, 140656834555903, +STORE, 140656836763648, 140656836788223, +STORE, 140656830070784, 140656832331775, +SNULL, 140656830070784, 140656830222335, +STORE, 140656830222336, 140656832331775, +STORE, 140656830070784, 140656830222335, +SNULL, 140656832315391, 140656832331775, +STORE, 140656830222336, 140656832315391, +STORE, 140656832315392, 140656832331775, +SNULL, 140656832315392, 140656832323583, +STORE, 140656832323584, 140656832331775, +STORE, 140656832315392, 140656832323583, +ERASE, 140656832315392, 140656832323583, +STORE, 140656832315392, 140656832323583, +ERASE, 140656832323584, 140656832331775, +STORE, 140656832323584, 140656832331775, +STORE, 140656827940864, 140656830070783, +SNULL, 140656827940864, 140656827969535, +STORE, 140656827969536, 140656830070783, +STORE, 140656827940864, 140656827969535, +SNULL, 140656830062591, 140656830070783, +STORE, 140656827969536, 140656830062591, +STORE, 140656830062592, 140656830070783, +ERASE, 140656830062592, 140656830070783, +STORE, 140656830062592, 140656830070783, +STORE, 140656825724928, 140656827940863, +SNULL, 140656825724928, 140656825823231, +STORE, 140656825823232, 140656827940863, +STORE, 140656825724928, 140656825823231, +SNULL, 140656827916287, 140656827940863, +STORE, 140656825823232, 140656827916287, +STORE, 140656827916288, 140656827940863, +SNULL, 140656827916288, 140656827924479, +STORE, 140656827924480, 140656827940863, +STORE, 140656827916288, 140656827924479, +ERASE, 140656827916288, 140656827924479, +STORE, 140656827916288, 140656827924479, +ERASE, 140656827924480, 140656827940863, +STORE, 140656827924480, 140656827940863, +STORE, 140656821927936, 140656825724927, +SNULL, 140656821927936, 140656823586815, +STORE, 140656823586816, 140656825724927, +STORE, 140656821927936, 140656823586815, +SNULL, 140656825683967, 140656825724927, +STORE, 140656823586816, 140656825683967, +STORE, 140656825683968, 140656825724927, +SNULL, 140656825683968, 140656825708543, +STORE, 140656825708544, 140656825724927, +STORE, 140656825683968, 140656825708543, +ERASE, 140656825683968, 140656825708543, +STORE, 140656825683968, 140656825708543, +ERASE, 140656825708544, 140656825724927, +STORE, 140656825708544, 140656825724927, +STORE, 140656819806208, 140656821927935, +SNULL, 140656819806208, 140656819822591, +STORE, 140656819822592, 140656821927935, +STORE, 140656819806208, 140656819822591, +SNULL, 140656821919743, 140656821927935, +STORE, 140656819822592, 140656821919743, +STORE, 140656821919744, 140656821927935, +ERASE, 140656821919744, 140656821927935, +STORE, 140656821919744, 140656821927935, +STORE, 140656836755456, 140656836763647, +STORE, 140656817553408, 140656819806207, +SNULL, 140656817553408, 140656817704959, +STORE, 140656817704960, 140656819806207, +STORE, 140656817553408, 140656817704959, +SNULL, 140656819798015, 140656819806207, +STORE, 140656817704960, 140656819798015, +STORE, 140656819798016, 140656819806207, +ERASE, 140656819798016, 140656819806207, +STORE, 140656819798016, 140656819806207, +STORE, 140656815382528, 140656817553407, +SNULL, 140656815382528, 140656815452159, +STORE, 140656815452160, 140656817553407, +STORE, 140656815382528, 140656815452159, +SNULL, 140656817545215, 140656817553407, +STORE, 140656815452160, 140656817545215, +STORE, 140656817545216, 140656817553407, +ERASE, 140656817545216, 140656817553407, +STORE, 140656817545216, 140656817553407, +STORE, 140656812171264, 140656815382527, +SNULL, 140656812171264, 140656813248511, +STORE, 140656813248512, 140656815382527, +STORE, 140656812171264, 140656813248511, +SNULL, 140656815345663, 140656815382527, +STORE, 140656813248512, 140656815345663, +STORE, 140656815345664, 140656815382527, +ERASE, 140656815345664, 140656815382527, +STORE, 140656815345664, 140656815382527, +STORE, 140656810037248, 140656812171263, +SNULL, 140656810037248, 140656810065919, +STORE, 140656810065920, 140656812171263, +STORE, 140656810037248, 140656810065919, +SNULL, 140656812163071, 140656812171263, +STORE, 140656810065920, 140656812163071, +STORE, 140656812163072, 140656812171263, +ERASE, 140656812163072, 140656812171263, +STORE, 140656812163072, 140656812171263, +STORE, 140656807727104, 140656810037247, +SNULL, 140656807727104, 140656807931903, +STORE, 140656807931904, 140656810037247, +STORE, 140656807727104, 140656807931903, +SNULL, 140656810029055, 140656810037247, +STORE, 140656807931904, 140656810029055, +STORE, 140656810029056, 140656810037247, +ERASE, 140656810029056, 140656810037247, +STORE, 140656810029056, 140656810037247, +STORE, 140656805343232, 140656807727103, +SNULL, 140656805343232, 140656805535743, +STORE, 140656805535744, 140656807727103, +STORE, 140656805343232, 140656805535743, +SNULL, 140656807628799, 140656807727103, +STORE, 140656805535744, 140656807628799, +STORE, 140656807628800, 140656807727103, +ERASE, 140656807628800, 140656807727103, +STORE, 140656807628800, 140656807727103, +STORE, 140656836747264, 140656836763647, +STORE, 140656802775040, 140656805343231, +SNULL, 140656802775040, 140656803241983, +STORE, 140656803241984, 140656805343231, +STORE, 140656802775040, 140656803241983, +SNULL, 140656805335039, 140656805343231, +STORE, 140656803241984, 140656805335039, +STORE, 140656805335040, 140656805343231, +ERASE, 140656805335040, 140656805343231, +STORE, 140656805335040, 140656805343231, +STORE, 140656800661504, 140656802775039, +SNULL, 140656800661504, 140656800673791, +STORE, 140656800673792, 140656802775039, +STORE, 140656800661504, 140656800673791, +SNULL, 140656802766847, 140656802775039, +STORE, 140656800673792, 140656802766847, +STORE, 140656802766848, 140656802775039, +ERASE, 140656802766848, 140656802775039, +STORE, 140656802766848, 140656802775039, +STORE, 140656798482432, 140656800661503, +SNULL, 140656798482432, 140656798560255, +STORE, 140656798560256, 140656800661503, +STORE, 140656798482432, 140656798560255, +SNULL, 140656800653311, 140656800661503, +STORE, 140656798560256, 140656800653311, +STORE, 140656800653312, 140656800661503, +ERASE, 140656800653312, 140656800661503, +STORE, 140656800653312, 140656800661503, +STORE, 140656796364800, 140656798482431, +SNULL, 140656796364800, 140656796381183, +STORE, 140656796381184, 140656798482431, +STORE, 140656796364800, 140656796381183, +SNULL, 140656798474239, 140656798482431, +STORE, 140656796381184, 140656798474239, +STORE, 140656798474240, 140656798482431, +ERASE, 140656798474240, 140656798482431, +STORE, 140656798474240, 140656798482431, +STORE, 140656836739072, 140656836763647, +STORE, 140656836726784, 140656836763647, +SNULL, 140656825700351, 140656825708543, +STORE, 140656825683968, 140656825700351, +STORE, 140656825700352, 140656825708543, +SNULL, 140656798478335, 140656798482431, +STORE, 140656798474240, 140656798478335, +STORE, 140656798478336, 140656798482431, +SNULL, 140656800657407, 140656800661503, +STORE, 140656800653312, 140656800657407, +STORE, 140656800657408, 140656800661503, +SNULL, 140656802770943, 140656802775039, +STORE, 140656802766848, 140656802770943, +STORE, 140656802770944, 140656802775039, +SNULL, 140656827920383, 140656827924479, +STORE, 140656827916288, 140656827920383, +STORE, 140656827920384, 140656827924479, +SNULL, 140656805339135, 140656805343231, +STORE, 140656805335040, 140656805339135, +STORE, 140656805339136, 140656805343231, +SNULL, 140656807723007, 140656807727103, +STORE, 140656807628800, 140656807723007, +STORE, 140656807723008, 140656807727103, +SNULL, 140656810033151, 140656810037247, +STORE, 140656810029056, 140656810033151, +STORE, 140656810033152, 140656810037247, +SNULL, 140656812167167, 140656812171263, +STORE, 140656812163072, 140656812167167, +STORE, 140656812167168, 140656812171263, +SNULL, 140656815353855, 140656815382527, +STORE, 140656815345664, 140656815353855, +STORE, 140656815353856, 140656815382527, +SNULL, 140656817549311, 140656817553407, +STORE, 140656817545216, 140656817549311, +STORE, 140656817549312, 140656817553407, +SNULL, 140656819802111, 140656819806207, +STORE, 140656819798016, 140656819802111, +STORE, 140656819802112, 140656819806207, +SNULL, 140656821923839, 140656821927935, +STORE, 140656821919744, 140656821923839, +STORE, 140656821923840, 140656821927935, +SNULL, 140656830066687, 140656830070783, +STORE, 140656830062592, 140656830066687, +STORE, 140656830066688, 140656830070783, +SNULL, 140656832319487, 140656832323583, +STORE, 140656832315392, 140656832319487, +STORE, 140656832319488, 140656832323583, +SNULL, 140656834547711, 140656834551807, +STORE, 140656833982464, 140656834547711, +STORE, 140656834547712, 140656834551807, +SNULL, 94730166759423, 94730166763519, +STORE, 94730166751232, 94730166759423, +STORE, 94730166759424, 94730166763519, +SNULL, 140656836800511, 140656836804607, +STORE, 140656836796416, 140656836800511, +STORE, 140656836800512, 140656836804607, +ERASE, 140656836763648, 140656836788223, +STORE, 94730171318272, 94730171453439, +STORE, 140656836784128, 140656836788223, +STORE, 140656836780032, 140656836784127, +STORE, 140656791920640, 140656796364799, +STORE, 140656836775936, 140656836780031, +STORE, 140656787476480, 140656791920639, +STORE, 140656779083776, 140656787476479, +SNULL, 140656779087871, 140656787476479, +STORE, 140656779083776, 140656779087871, +STORE, 140656779087872, 140656787476479, +STORE, 140656836771840, 140656836775935, +STORE, 140656774639616, 140656779083775, +STORE, 140656766246912, 140656774639615, +SNULL, 140656766251007, 140656774639615, +STORE, 140656766246912, 140656766251007, +STORE, 140656766251008, 140656774639615, +ERASE, 140656791920640, 140656796364799, +ERASE, 140656836780032, 140656836784127, +ERASE, 140656787476480, 140656791920639, +ERASE, 140656836775936, 140656836780031, +STORE, 140656836780032, 140656836784127, +STORE, 140656791920640, 140656796364799, +STORE, 140656836775936, 140656836780031, +STORE, 140656787476480, 140656791920639, +ERASE, 140656774639616, 140656779083775, }; int cnt = 0; MA_STATE(mas, mt, 0, 0); @@ -10466,9 +10735,28 @@ STORE, 140222970597376, 140222970605567, check_erase2_testset(mt, set18, ARRAY_SIZE(set18)); rcu_barrier(); mas_get_unmapped_area_rev(&mas, 4096, 140222972858368, 2215936); - printk("Found %lu\n", mas.index); MT_BUG_ON(mt, mas.index != 140222966259712); mtree_destroy(mt); + + /* set19 found 2 bugs in prev. + * 1. If we hit root without finding anything, then there was an + * infinite loop. + * 2. The first ascending wasn't using the correct slot which may have + * have caused missed entries. + */ + mt_set_non_kernel(99); + mas_reset(&mas); + mtree_init(mt, MAPLE_ALLOC_RANGE); + check_erase2_testset(mt, set19, ARRAY_SIZE(set19)); + rcu_barrier(); + mt_dump(mt); + mas.index = 140656779083776; + entry = mas_find(&mas, ULONG_MAX); + MT_BUG_ON(mt, entry != xa_mk_value(140656779083776)); + entry = mas_prev(&mas, 0); + MT_BUG_ON(mt, entry != xa_mk_value(140656766251008)); + + mtree_destroy(mt); } static noinline void check_alloc_rev_range(struct maple_tree *mt) -- 2.50.1