// Bartok uses the extra field in the PageTable to easily
// map from a stack address to the thread that owns that stack.
// This is used to implement GetCurrentThread.
// Singularity uses a different mechanism that does not involve
// the extra data at all.
private static unsafe void SetStackPages(UIntPtr startAddr,
UIntPtr endAddr,
Thread thread)
{
UIntPtr startPage = PageTable.Page(startAddr);
UIntPtr endPage = PageTable.Page(endAddr);
UIntPtr pageCount = endPage - startPage;
PageTable.VerifyType(startPage, pageCount, PageType.Unallocated);
PageTable.VerifyExtra(startPage, pageCount, 0);
PageTable.SetType(startPage, pageCount, PageType.Stack);
PageTable.SetExtra(startPage, pageCount,
(uint)thread.threadIndex);
}