Re: [PATCH v9 0/8] MR1628: ntdll: Implement Low Fragmentation Heap.

[Jinoh Kang (＠iamahuman)]

Jinoh Kang (@iamahuman) commented about dlls/ntdll/heap.c:
> - BOOL enable = FALSE;
> -
> - if (bin == heap->bins && alloc > 0x10) enable = TRUE;
> - else if (bin - heap->bins < 0x30 && alloc > 0x800) enable = TRUE;
> - else if (bin - heap->bins < 0x30 && alloc - freed > 0x10) enable = TRUE;
> - else if (alloc - freed > 0x400000 / block_size) enable = TRUE;
> - if (!enable) return;
> -
> - if (ReadNoFence( &heap->compat_info ) != HEAP_LFH)
> - {
> -
>    ULONG info = HEAP_LFH;
> -
>    RtlSetHeapInformation( heap, HeapCompatibilityInformation, &info, sizeof(info) );
> - }
> -
> - /* paired with ReadAcquire in heap_allocate_block_lfh. */
> - WriteRelease( &bin->enabled, TRUE );

`heap_allocate_block_lfh` would not be introduced until commit "ntdll: Implement Low Fragmentation Heap frontend."  For atomic commits, you should first use `WriteNoFence` and then switch to `WriteRelease` later.