Fixing segmentOffset access (#100)

* Fixing computation of segment offset * clean up
microsoft · Feb 26, 2019 · 35e8732 · 35e8732
1 parent f970f4e
commit 35e8732
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Showing 3 changed files with 22 additions and 23 deletions.
diff --git a/cs/src/core/Allocator/AllocatorBase.cs b/cs/src/core/Allocator/AllocatorBase.cs
@@ -343,9 +343,8 @@ public unsafe abstract class AllocatorBase<Key, Value> : IDisposable
         /// <summary>
         /// Clear page
         /// </summary>
-        /// <param name="page"></param>
-        /// <param name="pageZero"></param>
-        protected abstract void ClearPage(int page, bool pageZero);
+        /// <param name="page">Page number to be cleared</param>
+        protected abstract void ClearPage(long page);
         /// <summary>
         /// Write page (async)
         /// </summary>
@@ -378,6 +377,16 @@ public unsafe abstract class AllocatorBase<Key, Value> : IDisposable
         /// </summary>
         /// <returns></returns>
         public abstract long[] GetSegmentOffsets();
+
+        /// <summary>
+        /// Pull-based scan interface for HLOG
+        /// </summary>
+        /// <param name="beginAddress"></param>
+        /// <param name="endAddress"></param>
+        /// <param name="scanBufferingMode"></param>
+        /// <returns></returns>
+        public abstract IFasterScanIterator<Key, Value> Scan(long beginAddress, long endAddress, ScanBufferingMode scanBufferingMode = ScanBufferingMode.DoublePageBuffering);
+
         #endregion
 
         /// <summary>
@@ -850,11 +859,11 @@ public void OnPagesClosed(long newSafeHeadAddress)
                         var oldStatus = PageStatusIndicator[closePage].PageFlushCloseStatus;
                         if (oldStatus.PageFlushStatus == PMMFlushStatus.Flushed)
                         {
-                            ClearPage(closePage, (closePageAddress >> LogPageSizeBits) == 0);
+                            ClearPage(closePageAddress >> LogPageSizeBits);
                         }
                         else
                         {
-                            throw new Exception("Impossible");
+                            throw new Exception("Error: page should already be flushed at this point");
                         }
 
                         var newStatus = oldStatus;
@@ -1161,7 +1170,7 @@ internal void AsyncReadRecordToMemory(long fromLogical, int numBytes, IOCompleti
                 }
                 else
                 {
-                    ClearPage(pageIndex, readPage == 0);
+                    ClearPage(readPage);
                 }
                 var asyncResult = new PageAsyncReadResult<TContext>()
                 {
@@ -1421,7 +1430,7 @@ private void AsyncFlushPageCallback(uint errorCode, uint numBytes, NativeOverlap
                         var oldStatus = PageStatusIndicator[result.page % BufferSize].PageFlushCloseStatus;
                         if (oldStatus.PageCloseStatus == PMMCloseStatus.Closed)
                         {
-                            ClearPage((int)(result.page % BufferSize), result.page == 0);
+                            throw new Exception("Error: page should not be closed at this point");
                         }
                         var newStatus = oldStatus;
                         newStatus.PageFlushStatus = PMMFlushStatus.Flushed;
@@ -1479,14 +1488,5 @@ public virtual void ShallowCopy(ref Value src, ref Value dst)
         {
             dst = src;
         }
-
-        /// <summary>
-        /// Pull-based scan interface for HLOG
-        /// </summary>
-        /// <param name="beginAddress"></param>
-        /// <param name="endAddress"></param>
-        /// <param name="scanBufferingMode"></param>
-        /// <returns></returns>
-        public abstract IFasterScanIterator<Key, Value> Scan(long beginAddress, long endAddress, ScanBufferingMode scanBufferingMode = ScanBufferingMode.DoublePageBuffering);
     }
 }
diff --git a/cs/src/core/Allocator/BlittableAllocator.cs b/cs/src/core/Allocator/BlittableAllocator.cs
@@ -241,9 +241,9 @@ public override long GetStartLogicalAddress(long page)
         }
 
 
-        protected override void ClearPage(int page, bool pageZero)
+        protected override void ClearPage(long page)
         {
-            Array.Clear(values[page], 0, values[page].Length);
+            Array.Clear(values[page % BufferSize], 0, values[page % BufferSize].Length);
         }
 
         private void WriteAsync<TContext>(IntPtr alignedSourceAddress, ulong alignedDestinationAddress, uint numBytesToWrite,

diff --git a/cs/src/core/Allocator/GenericAllocator.cs b/cs/src/core/Allocator/GenericAllocator.cs
@@ -232,18 +232,17 @@ protected override void WriteAsync<TContext>(long flushPage, IOCompletionCallbac
 
 
 
-        protected override void ClearPage(int page, bool pageZero)
+        protected override void ClearPage(long page)
         {
-            Array.Clear(values[page], 0, values[page].Length);
+            Array.Clear(values[page % BufferSize], 0, values[page % BufferSize].Length);
 
             // Close segments
             var thisCloseSegment = page >> (LogSegmentSizeBits - LogPageSizeBits);
-            var nextClosePage = page + 1;
-            var nextCloseSegment = nextClosePage >> (LogSegmentSizeBits - LogPageSizeBits);
+            var nextCloseSegment = (page + 1) >> (LogSegmentSizeBits - LogPageSizeBits);
 
             if (thisCloseSegment != nextCloseSegment)
             {
-                // Last page in current segment
+                // We are clearing the last page in current segment
                 segmentOffsets[thisCloseSegment % SegmentBufferSize] = 0;
             }
         }