Learn gem5 #4 (Event-driven programming)

だいぶ空いてしまった。

Event-driven programming

ソースを編集。

--- ../backup/1/src/learning_gem5/part2/hello_object.hh 2024-04-03 22:02:25.385861133 +0900
+++ src/learning_gem5/part2/hello_object.hh     2024-04-03 22:04:29.235837762 +0900
@@ -9,8 +9,12 @@

 class HelloObject : public SimObject
 {
+  private:
+    void processEvent();
+    EventFunctionWrapper event;
   public:
     HelloObject(const HelloObjectParams &p);
+    void startup() override;
 };

 } // namespace gem5

--- ../backup/1/src/learning_gem5/part2/hello_object.cc 2024-03-24 16:17:08.087853809 +0900
+++ src/learning_gem5/part2/hello_object.cc     2024-04-03 22:06:04.745818640 +0900
@@ -8,9 +8,19 @@
 {

 HelloObject::HelloObject(const HelloObjectParams &params) :
-    SimObject(params)
+    SimObject(params), event([this]{processEvent();}, name())
 {
     DPRINTF(HelloExample, "Created the hello object\n");
 }

+void HelloObject::processEvent()
+{
+  DPRINTF(HelloExample, "Hello world! Processing the event!\n");
+}
+
+void HelloObject::startup()
+{
+  schedule(event, 100);
+}
+
 } // namespace gem5

実行する。

$ scons build/X86/gem5.opt -j20
$ build/X86/gem5.opt --debug-flags=HelloExample configs/learning_gem5/part2/run_hello.py

以下のメッセージが出る。

    100: hello: Hello world! Processing the event!

さらに変更を加える。

--- ../backup/2/src/learning_gem5/part2/hello_object.hh 2024-04-03 22:17:05.645691333 +0900
+++ src/learning_gem5/part2/hello_object.hh     2024-04-03 22:17:41.355683887 +0900
@@ -12,6 +12,8 @@
   private:
     void processEvent();
     EventFunctionWrapper event;
+    const Tick latency;
+    int timesLeft;
   public:
     HelloObject(const HelloObjectParams &p);
     void startup() override;

--- ../backup/2/src/learning_gem5/part2/hello_object.cc 2024-04-03 22:17:10.005690492 +0900
+++ src/learning_gem5/part2/hello_object.cc     2024-04-03 22:19:40.035660455 +0900
@@ -8,19 +8,27 @@
 {

 HelloObject::HelloObject(const HelloObjectParams &params) :
-    SimObject(params), event([this]{processEvent();}, name())
+    SimObject(params), event([this]{processEvent();}, name()),
+    latency(100), timesLeft(10)
 {
     DPRINTF(HelloExample, "Created the hello object\n");
 }

 void HelloObject::processEvent()
 {
-  DPRINTF(HelloExample, "Hello world! Processing the event!\n");
+  timesLeft--;
+  DPRINTF(HelloExample, "Hello world! Processing the event! %d left\n", timesLeft);
+
+  if (timesLeft <= 0) {
+    DPRINTF(HelloExample, "Done firing!\n");
+  } else {
+    schedule(event, curTick() + latency);
+  }
 }

 void HelloObject::startup()
 {
-  schedule(event, 100);
+  schedule(event, latency);
 }

 } // namespace gem5

実行する。

$ scons build/X86/gem5.opt -j20
$ build/X86/gem5.opt --debug-flags=HelloExample configs/learning_gem5/part2/run_hello.py

以下のメッセージが出る。

src/sim/simulate.cc:199: info: Entering event queue @ 0.  Starting simulation...
    100: hello: Hello world! Processing the event! 9 left
    200: hello: Hello world! Processing the event! 8 left
    300: hello: Hello world! Processing the event! 7 left
    400: hello: Hello world! Processing the event! 6 left
    500: hello: Hello world! Processing the event! 5 left
    600: hello: Hello world! Processing the event! 4 left
    700: hello: Hello world! Processing the event! 3 left
    800: hello: Hello world! Processing the event! 2 left
    900: hello: Hello world! Processing the event! 1 left
   1000: hello: Hello world! Processing the event! 0 left
   1000: hello: Done firing!