commit 21020aa778e8a26633c8820b1c89d52f0a4fff23
author Yu-hsin Wang <yuhsingw@google.com> Thu Oct 13 17:05:39 2022 +0800
committer Yu-hsin Wang <yuhsingw@google.com> Mon Oct 17 02:04:40 2022 +0000
tree adc09657f6b7a6bb5f70bac8ee2f22f1f838b52a
parent 9e76e7a321a6ca657d0dca2e13ecb74fe7e74ad0

systemc: prevent from invalidate callback re-registration

Remove the redundant callback to save the memory.

Change-Id: Iafa6ada06f62ac2928a580c25ebbcbbe3f195670
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64474
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Earl Ou <shunhsingou@google.com>

src/systemc/tlm_bridge/tlm_to_gem5.cc

diff --git a/src/systemc/tlm_bridge/tlm_to_gem5.cc b/src/systemc/tlm_bridge/tlm_to_gem5.cc
index 9fd887d..7aec14f 100644
--- a/src/systemc/tlm_bridge/tlm_to_gem5.cc
+++ b/src/systemc/tlm_bridge/tlm_to_gem5.cc
@@ -285,6 +285,7 @@
 {
     socket->invalidate_direct_mem_ptr(
             backdoor.range().start(), backdoor.range().end());
+    requestedBackdoors.erase(const_cast<gem5::MemBackdoorPtr>(&backdoor));
 }
 
 template <unsigned int BITWIDTH>
@@ -417,12 +418,16 @@
             access = (access_t)(access | tlm::tlm_dmi::DMI_ACCESS_WRITE);
         dmi_data.set_granted_access(access);
 
-        backdoor->addInvalidationCallback(
-            [this](const MemBackdoor &backdoor)
-            {
-                invalidateDmi(backdoor);
-            }
-        );
+        // We only need to register the callback at the first time.
+        if (requestedBackdoors.find(backdoor) == requestedBackdoors.end()) {
+            backdoor->addInvalidationCallback(
+                [this](const MemBackdoor &backdoor)
+                {
+                    invalidateDmi(backdoor);
+                }
+            );
+            requestedBackdoors.emplace(backdoor);
+        }
     }
 
     gem5::Packet::SenderState *senderState = pkt->popSenderState();

src/systemc/tlm_bridge/tlm_to_gem5.hh

diff --git a/src/systemc/tlm_bridge/tlm_to_gem5.hh b/src/systemc/tlm_bridge/tlm_to_gem5.hh
index e452d8b..deb332e 100644
--- a/src/systemc/tlm_bridge/tlm_to_gem5.hh
+++ b/src/systemc/tlm_bridge/tlm_to_gem5.hh
@@ -59,6 +59,7 @@
 #define __SYSTEMC_TLM_BRIDGE_TLM_TO_GEM5_HH__
 
 #include <functional>
+#include <unordered_set>
 #include <utility>
 
 #include "mem/port.hh"
@@ -122,6 +123,8 @@
 
     bool responseInProgress;
 
+    std::unordered_set<gem5::MemBackdoorPtr> requestedBackdoors;
+
     BridgeRequestPort bmp;
     tlm_utils::simple_target_socket<
         TlmToGem5Bridge<BITWIDTH>, BITWIDTH> socket;