mem-cache: allow prefetchers to emit page crossing references

QueuedPrefetcher takes the responsability to check for page
crossing references.

Change-Id: I0ae6bf8be465118990d9ea1cac0da8f70e69aeb1
Reviewed-on: https://gem5-review.googlesource.com/c/14735
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>

1 files changed, 12 insertions, 6 deletions

diff --git a/src/mem/cache/prefetch/queued.cc b/src/mem/cache/prefetch/queued.cc
index f48ea185d..bce6fbb97 100644
--- a/src/mem/cache/prefetch/queued.cc
+++ b/src/mem/cache/prefetch/queued.cc
@@ -93,14 +93,20 @@ QueuedPrefetcher::notify(const PacketPtr &pkt, const PrefetchInfo &pfi)
         // Block align prefetch address
         addr_prio.first = blockAddress(addr_prio.first);
 
-        PrefetchInfo new_pfi(pfi,addr_prio.first);
+        if (samePage(pfi.getAddr(), addr_prio.first)) {
+            PrefetchInfo new_pfi(pfi,addr_prio.first);
 
-        pfIdentified++;
-        DPRINTF(HWPrefetch, "Found a pf candidate addr: %#x, "
-                "inserting into prefetch queue.\n", new_pfi.getAddr());
+            pfIdentified++;
+            DPRINTF(HWPrefetch, "Found a pf candidate addr: %#x, "
+                    "inserting into prefetch queue.\n", new_pfi.getAddr());
 
-        // Create and insert the request
-        insert(pkt, new_pfi, addr_prio.second);
+            // Create and insert the request
+            insert(pkt, new_pfi, addr_prio.second);
+        } else {
+            // Record the number of page crossing prefetches generate
+            pfSpanPage += 1;
+            DPRINTF(HWPrefetch, "Ignoring page crossing prefetch.\n");
+        }
     }
 }