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replace atomics with C11/C++ atomics with explicit memory order; passes tsan. Issue #130

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daan
2020-07-26 18:00:38 -07:00
parent a468430772
commit ef8e5d18a6
14 changed files with 248 additions and 315 deletions
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14
src/bitmap.inc.c
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@@ -121,9 +121,9 @@ static inline bool mi_bitmap_try_claim_field(mi_bitmap_t bitmap, size_t bitmap_f
mi_assert_internal(bitmap_fields > idx); UNUSED(bitmap_fields);
mi_assert_internal(bitidx + count <= MI_BITMAP_FIELD_BITS);
uintptr_t field = mi_atomic_read_relaxed(&bitmap[idx]);
uintptr_t field = mi_atomic_load_relaxed(&bitmap[idx]);
if ((field & mask) == 0) { // free?
if (mi_atomic_cas_strong(&bitmap[idx], &field, (field|mask))) {
if (mi_atomic_cas_strong_acq_rel(&bitmap[idx], &field, (field|mask))) {
// claimed!
return true;
}
@@ -138,7 +138,7 @@ static inline bool mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx
{
mi_assert_internal(bitmap_idx != NULL);
_Atomic(uintptr_t)* field = &bitmap[idx];
uintptr_t map = mi_atomic_read(field);
uintptr_t map = mi_atomic_load_relaxed(field);
if (map==MI_BITMAP_FIELD_FULL) return false; // short cut
// search for 0-bit sequence of length count
@@ -158,7 +158,7 @@ static inline bool mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx
mi_assert_internal((m >> bitidx) == mask); // no overflow?
const uintptr_t newmap = map | m;
mi_assert_internal((newmap^map) >> bitidx == mask);
if (!mi_atomic_cas_weak(field, &map, newmap)) { // TODO: use strong cas here?
if (!mi_atomic_cas_weak_acq_rel(field, &map, newmap)) { // TODO: use strong cas here?
// no success, another thread claimed concurrently.. keep going (with updated `map`)
continue;
}
@@ -204,7 +204,7 @@ static inline bool mi_bitmap_unclaim(mi_bitmap_t bitmap, size_t bitmap_fields, s
const uintptr_t mask = mi_bitmap_mask_(count, bitidx);
mi_assert_internal(bitmap_fields > idx); UNUSED(bitmap_fields);
// mi_assert_internal((bitmap[idx] & mask) == mask);
uintptr_t prev = mi_atomic_and(&bitmap[idx], ~mask);
uintptr_t prev = mi_atomic_and_acq_rel(&bitmap[idx], ~mask);
return ((prev & mask) == mask);
}
@@ -217,7 +217,7 @@ static inline bool mi_bitmap_claim(mi_bitmap_t bitmap, size_t bitmap_fields, siz
const uintptr_t mask = mi_bitmap_mask_(count, bitidx);
mi_assert_internal(bitmap_fields > idx); UNUSED(bitmap_fields);
//mi_assert_internal(any_zero != NULL || (bitmap[idx] & mask) == 0);
uintptr_t prev = mi_atomic_or(&bitmap[idx], mask);
uintptr_t prev = mi_atomic_or_acq_rel(&bitmap[idx], mask);
if (any_zero != NULL) *any_zero = ((prev & mask) != mask);
return ((prev & mask) == 0);
}
@@ -228,7 +228,7 @@ static inline bool mi_bitmap_is_claimedx(mi_bitmap_t bitmap, size_t bitmap_field
const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
const uintptr_t mask = mi_bitmap_mask_(count, bitidx);
mi_assert_internal(bitmap_fields > idx); UNUSED(bitmap_fields);
uintptr_t field = mi_atomic_read_relaxed(&bitmap[idx]);
uintptr_t field = mi_atomic_load_relaxed(&bitmap[idx]);
if (any_ones != NULL) *any_ones = ((field & mask) != 0);
return ((field & mask) == mask);
}