ticketlock foo

main.cc

@@ -13,7 +13,7 @@
 #include "device/ps2controller.h"
 #include "arch/ioapic.h"
 #include "user/app1/appl.h"
-
+#include "sync/ticketlock.h"
 TextStream kout = TextStream(0, 80, 0, 10, true);
 
 //TextStream dout[8] = {
@@ -47,6 +47,7 @@ CopyStream copystream[Core::MAX]{
     {&dout[6], &sout},
     {&dout[7], &sout},
 };
+Ticketlock ticketlock;
 
 OutputStream* copyout[Core::MAX]{
     &dout[0],
@@ -99,7 +100,6 @@ extern "C" int main() {
   PS2Controller::drainBuffer();
 
   Application{}.action();
-
   while (true){
   }
 

sync/ticketlock.cc

@@ -0,0 +1,12 @@
+#include "sync/ticketlock.h"
+
+void Ticketlock::lock() {
+    uint64_t ticket = __atomic_fetch_add(&ticket_count, 1, __ATOMIC_SEQ_CST);
+    while (ticket != ticket_current) {
+        Core::pause();
+    }
+}
+
+void Ticketlock::unlock() {
+    __atomic_fetch_add(&ticket_current, 1, __ATOMIC_SEQ_CST);
+}

sync/ticketlock.h

@@ -4,6 +4,8 @@
 
 #pragma once
 
+#include "arch/core.h"
+#include "arch/cache.h"
 /*! \brief Using Ticketlocks, it is possible to serialize blocks of code
  *  that might otherwise run in parallel on multiple CPU cores,
  *  or be interleaved due to interrupts or scheduling.
@@ -29,12 +31,17 @@ class Ticketlock {
   Ticketlock(const Ticketlock& copy) = delete;
   Ticketlock& operator=(const Ticketlock&) = delete;
 
+  
+ private:
+	volatile uint64_t ticket_current;
+	volatile uint64_t ticket_count;
+
  public:
   /*! \brief Constructor
    *
    * \todo(12) Complete Constructor (for \MPStuBS)
    */
-  consteval Ticketlock() {}
+  consteval Ticketlock() : ticket_current(0), ticket_count(0) {}
 
   /*! \brief Enters the critical area. In case the area is already locked,
    *  \ref lock() will actively wait until the area can be entered.
@@ -42,11 +49,11 @@ class Ticketlock {
    * \see \ref Core::pause()
    * \todo(12) Implement Method (for \MPStuBS)
    */
-  void lock() {}
+  void lock();
 
   /*! \brief Unblocks the critical area.
    *
    * \todo(12) Implement Method (for \MPStuBS)
    */
-  void unlock() {}
+  void unlock();
 };

user/app1/appl.cc

@@ -4,7 +4,8 @@
 #include "../../device/ps2controller.h"
 #include "../../object/outputstream.h"
 #include "../../device/textstream.h"
-
+#include "../../sync/ticketlock.h"
+#include "../../arch/core.h"
 char text[] = "Ich mag\n\
 Saftige Pflaumen voller Aroma\n\
 Ich knuddel jede Oma ins Koma\n\
@@ -19,7 +20,7 @@ Und wacht sie aus'm Koma auf, kriegt sie von mir 'n Sticker\n\
 \n";
 
 extern TextStream kout;
-
+extern Ticketlock ticketlock;
 void activeWaitDelay(uint64_t cycles) {
     uint64_t counter = 0; // Use volatile to prevent optimization
     for (uint64_t i = 0; i < cycles; ++i) {
@@ -31,6 +32,8 @@ void activeWaitDelay(uint64_t cycles) {
 void Application::action() {  // NOLINT
 	uint16_t cnt = 0;
 	while (1) {
+		Core::Interrupt::disable();
+        ticketlock.lock();
 		while(text[cnt++] != '\n'){
 			kout << text[cnt-1];
 		}
@@ -39,5 +42,8 @@ void Application::action() {  // NOLINT
 		activeWaitDelay(1000000000);
 		if(cnt >= sizeof(text)-1)
 			cnt=0;
+
+		ticketlock.unlock();
+		Core::Interrupt::enable();
 	}
 }