public void DisposeMultiHandles([Values] bool smart)
{
// Create and initialize two overlapping Multi Region Handles, with PageSize granularity.
const int pageCount = 32;
const int overlapStart = 16;
Assert.AreEqual((0, 0), _tracking.GetRegionCounts());
IMultiRegionHandle handleLow = GetGranular(smart, 0, PageSize * pageCount, PageSize);
PreparePages(handleLow, pageCount);
Assert.AreEqual((pageCount, pageCount), _tracking.GetRegionCounts());
IMultiRegionHandle handleHigh = GetGranular(smart, PageSize * overlapStart, PageSize * pageCount, PageSize);
PreparePages(handleHigh, pageCount, PageSize * overlapStart);
// Combined pages (and assuming overlapStart <= pageCount) should be pageCount after overlapStart.
int totalPages = overlapStart + pageCount;
Assert.AreEqual((totalPages, totalPages), _tracking.GetRegionCounts());
handleLow.Dispose(); // After disposing one, the pages for the other remain.
Assert.AreEqual((pageCount, pageCount), _tracking.GetRegionCounts());
handleHigh.Dispose(); // After disposing the other, there are no pages left.
Assert.AreEqual((0, 0), _tracking.GetRegionCounts());
}
public void DirtyRegionOrdering([Values] bool smart)
{
const int pageCount = 32;
IMultiRegionHandle handle = GetGranular(smart, 0, PageSize * pageCount, PageSize);
Random random = new Random();
PreparePages(handle, pageCount);
IEnumerable <int> halfRange = Enumerable.Range(0, pageCount / 2);
List <int> odd = halfRange.Select(x => x * 2 + 1).ToList();
List <int> even = halfRange.Select(x => x * 2).ToList();
// Write to all the odd pages.
RandomOrder(random, odd, (i) =>
{
_tracking.VirtualMemoryEvent((ulong)i * PageSize, PageSize, true);
});
int oddRegionCount = ExpectQueryInOrder(handle, 0, PageSize * pageCount, (address) => (address / PageSize) % 2 == 1);
Assert.AreEqual(oddRegionCount, pageCount / 2); // Must have written to all odd pages.
// Write to all the even pages.
RandomOrder(random, even, (i) =>
{
_tracking.VirtualMemoryEvent((ulong)i * PageSize, PageSize, true);
});
int evenRegionCount = ExpectQueryInOrder(handle, 0, PageSize * pageCount, (address) => (address / PageSize) % 2 == 0);
Assert.AreEqual(evenRegionCount, pageCount / 2);
}
public void SmartRegionTracking()
{
// Smart multi region handles dynamically change their tracking granularity based on QueryMemory calls.
// This can save on reprotects on larger resources.
const int pageCount = 32;
IMultiRegionHandle handle = GetGranular(true, 0, PageSize * pageCount, PageSize);
// Query some large regions to prep the subdivision of the tracking region.
int[] regionSizes = new int[] { 6, 4, 3, 2, 6, 1 };
ulong address = 0;
for (int i = 0; i < regionSizes.Length; i++)
{
int region = regionSizes[i];
handle.QueryModified(address, (ulong)(PageSize * region), (address, size) => { });
// There should be a gap between regions,
// So that they don't combine and we can see the full effects.
address += (ulong)(PageSize * (region + 1));
}
// Clear modified.
handle.QueryModified((address, size) => { });
// Trigger each region with a 1 byte write.
address = 0;
for (int i = 0; i < regionSizes.Length; i++)
{
int region = regionSizes[i];
_tracking.VirtualMemoryEvent(address, 1, true);
address += (ulong)(PageSize * (region + 1));
}
int regionInd = 0;
ulong expectedAddress = 0;
// Expect each region to trigger in its entirety, in address ascending order.
handle.QueryModified((address, size) => {
int region = regionSizes[regionInd++];
Assert.AreEqual(address, expectedAddress);
Assert.AreEqual(size, (ulong)(PageSize * region));
expectedAddress += (ulong)(PageSize * (region + 1));
});
}
private void PreparePages(IMultiRegionHandle handle, int pageCount, ulong address = 0)
{
Random random = new Random();
// Make sure the list has minimum granularity (smart region changes granularity based on requested ranges)
RandomOrder(random, Enumerable.Range(0, pageCount).ToList(), (i) =>
{
ulong resultAddress = ulong.MaxValue;
handle.QueryModified((ulong)i * PageSize + address, PageSize, (address, range) =>
{
resultAddress = address;
});
Assert.AreEqual(resultAddress, (ulong)i * PageSize + address);
});
}
private int ExpectQueryInOrder(IMultiRegionHandle handle, ulong startAddress, ulong size, Func <ulong, bool> addressPredicate, int sequenceNumber)
{
int regionCount = 0;
ulong lastAddress = startAddress;
handle.QueryModified(startAddress, size, (address, range) =>
{
Assert.IsTrue(addressPredicate(address)); // Written pages must be even.
Assert.GreaterOrEqual(address, lastAddress); // Must be signalled in ascending order, regardless of write order.
lastAddress = address;
regionCount++;
}, sequenceNumber);
return(regionCount);
}
public void SequenceNumber([Values] bool smart)
{
// The sequence number can be used to ignore dirty flags, and defer their consumption until later.
// If a user consumes a dirty flag with sequence number 1, then there is a write to the protected region,
// the dirty flag will not be acknowledged until the sequence number is 2.
// This is useful for situations where we know that the data was complete when the sequence number was set.
// ...essentially, when that data can only be updated on a future sequence number.
const int pageCount = 32;
IMultiRegionHandle handle = GetGranular(smart, 0, PageSize * pageCount, PageSize);
PreparePages(handle, pageCount);
Random random = new Random();
IEnumerable <int> halfRange = Enumerable.Range(0, pageCount / 2);
List <int> odd = halfRange.Select(x => x * 2 + 1).ToList();
List <int> even = halfRange.Select(x => x * 2).ToList();
// Write to all the odd pages.
RandomOrder(random, odd, (i) =>
{
_tracking.VirtualMemoryEvent((ulong)i * PageSize, PageSize, true);
});
int oddRegionCount = 0;
// Track with sequence number 1. Future dirty flags should only be consumed with sequence number != 1.
// Only track the odd pages, so the even ones don't have their sequence number set.
foreach (int index in odd)
{
handle.QueryModified((ulong)index * PageSize, PageSize, (address, range) =>
{
oddRegionCount++;
}, 1);
}
Assert.AreEqual(oddRegionCount, pageCount / 2); // Must have written to all odd pages.
// Write to all pages.
_tracking.VirtualMemoryEvent(0, PageSize * pageCount, true);
// Only the even regions should be reported for sequence number 1.
int evenRegionCount = ExpectQueryInOrder(handle, 0, PageSize * pageCount, (address) => (address / PageSize) % 2 == 0, 1);
Assert.AreEqual(evenRegionCount, pageCount / 2); // Must have written to all even pages.
oddRegionCount = 0;
handle.QueryModified(0, PageSize * pageCount, (address, range) => { oddRegionCount++; }, 1);
Assert.AreEqual(oddRegionCount, 0); // Sequence number has not changed, so found no dirty subregions.
// With sequence number 2, all all pages should be reported as modified.
oddRegionCount = ExpectQueryInOrder(handle, 0, PageSize * pageCount, (address) => (address / PageSize) % 2 == 1, 2);
Assert.AreEqual(oddRegionCount, pageCount / 2); // Must have written to all odd pages.
}
