1 files changed, 55 insertions, 0 deletions
diff --git a/src/mongo/db/pagefault.cpp b/src/mongo/db/pagefault.cpp
new file mode 100644
index 00000000000..4b9b1b23e02
--- /dev/null
+++ b/src/mongo/db/pagefault.cpp
@@ -0,0 +1,55 @@
+// @file pagefault.cpp
+
+#include "pch.h"
+#include "diskloc.h"
+#include "pagefault.h"
+#include "client.h"
+#include "pdfile.h"
+#include "server.h"
+
+namespace mongo { 
+
+    PageFaultException::PageFaultException(Record *_r)
+    {
+        assert( cc()._pageFaultRetryableSection != 0 );
+        cc()._pageFaultRetryableSection->_laps++;
+        assert( cc()._pageFaultRetryableSection->_laps < 1000 );
+        r = _r;
+        era = LockMongoFilesShared::getEra();
+    }
+
+    void PageFaultException::touch() { 
+        assert( !d.dbMutex.atLeastReadLocked() );
+        LockMongoFilesShared lk;
+        if( LockMongoFilesShared::getEra() != era ) {
+            // files opened and closed.  we don't try to handle but just bail out; this is much simpler
+            // and less error prone and saves us from taking a dbmutex readlock.
+            dlog(2) << "era changed" << endl;
+            return;
+        }
+        r->touch();
+    }
+
+    PageFaultRetryableSection::~PageFaultRetryableSection() {
+        cc()._pageFaultRetryableSection = old;
+    }
+    PageFaultRetryableSection::PageFaultRetryableSection() {
+        _laps = 0;
+        old = cc()._pageFaultRetryableSection;
+        if( d.dbMutex.atLeastReadLocked() ) { 
+            cc()._pageFaultRetryableSection = 0;
+            if( debug || logLevel > 2 ) { 
+                LOGSOME << "info PageFaultRetryableSection will not yield, already locked upon reaching" << endl;
+            }
+        }
+        else if( cc()._pageFaultRetryableSection ) { 
+            cc()._pageFaultRetryableSection = 0;
+            dlog(2) << "info nested PageFaultRetryableSection will not yield on fault" << endl;
+        }
+        else {
+            cc()._pageFaultRetryableSection = this;
+            cc()._hasWrittenThisPass = false;
+        }
+    }
+
+}