diff -r 4833717b9d1e -r df27a0033426 src/mem/cache/base.hh
--- a/src/mem/cache/base.hh	Tue May 05 16:47:24 2015 +0100
+++ b/src/mem/cache/base.hh	Wed May 27 13:50:01 2015 +0100
@@ -404,6 +404,9 @@
     /** The number of cache copies performed. */
     Stats::Scalar cacheCopies;
 
+    /** The number of times a HW-prefetched block is evicted w/o reference. */
+    Stats::Scalar unusedPrefetches;
+
     /** Number of blocks written back per thread. */
     Stats::Vector writebacks;
 
diff -r 4833717b9d1e -r df27a0033426 src/mem/cache/base.cc
--- a/src/mem/cache/base.cc	Tue May 05 16:47:24 2015 +0100
+++ b/src/mem/cache/base.cc	Wed May 27 13:50:01 2015 +0100
@@ -439,6 +439,11 @@
         .desc("number of cache copies performed")
         ;
 
+    unusedPrefetches
+        .name(name() + ".unused_prefetches")
+        .desc("number of HardPF blocks evicted w/o reference")
+        ;
+
     writebacks
         .init(system->maxMasters())
         .name(name() + ".writebacks")
diff -r 4833717b9d1e -r df27a0033426 src/mem/cache/cache.cc
--- a/src/mem/cache/cache.cc	Tue May 05 16:47:24 2015 +0100
+++ b/src/mem/cache/cache.cc	Wed May 27 13:50:01 2015 +0100
@@ -1676,6 +1676,9 @@
                     addr, is_secure ? "s" : "ns",
                     blk->isDirty() ? "writeback" : "clean");
 
+            if (blk->wasPrefetched()) {
+                unusedPrefetches++;
+            }
             // Will send up Writeback/CleanEvict snoops via isCachedAbove
             // when pushing this writeback list into the write buffer.
             if (blk->isDirty() || writebackClean) {