kiper220/mimalloc
1
0
Fork 0
mirror of https://github.com/microsoft/mimalloc.git synced 2025-05-06 23:39:31 +03:00
Code Issues Projects Releases Packages Wiki Activity Actions

remove busy wait for arena reservation

Browse source
This commit is contained in:
daanx 2024-12-20 17:31:48 -08:00
parent bc459b5e16
commit 7141d9f164
1 changed files with 13 additions and 10 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

21
src/arena.c
View file

@ -453,7 +453,7 @@ static mi_decl_noinline void* mi_arena_try_alloc(
mi_assert(slice_count <= MI_ARENA_MAX_OBJ_SLICES);
mi_assert(alignment <= MI_ARENA_SLICE_ALIGN);
void* p;
again:
// try to find free slices in the arena's
p = mi_arena_try_find_free(slice_count, alignment, commit, allow_large, req_arena_id, tseq, memid);
if (p != NULL) return p;
@ -465,22 +465,25 @@ again:
if (_mi_preloading()) return NULL;
// otherwise, try to reserve a new arena -- but one thread at a time.. (todo: allow 2 or 4 to reduce contention?)
if (mi_lock_try_acquire(&mi_arena_reserve_lock)) {
const size_t arena_count = mi_arena_get_count();
if (mi_lock_acquire(&mi_arena_reserve_lock)) {
bool ok = true;
if (arena_count == mi_arena_get_count()) {
// we are the first to enter the lock, reserve a fresh arena
mi_arena_id_t arena_id = 0;
bool ok = mi_arena_reserve(mi_size_of_slices(slice_count), allow_large, req_arena_id, &arena_id);
ok = mi_arena_reserve(mi_size_of_slices(slice_count), allow_large, req_arena_id, &arena_id);
}
else {
// another thread already reserved a new arena
}
mi_lock_release(&mi_arena_reserve_lock);
if (ok) {
// and try allocate in there
// try once more to allocate in the new arena
mi_assert_internal(req_arena_id == _mi_arena_id_none());
p = mi_arena_try_find_free(slice_count, alignment, commit, allow_large, req_arena_id, tseq, memid);
if (p != NULL) return p;
}
}
else {
// if we are racing with another thread wait until the new arena is reserved (todo: a better yield?)
mi_atomic_yield();
goto again;
}
return NULL;
}