Implement timeout on wait_queue

fix #1

core/kthread.c

@@ -8,6 +8,7 @@
 #include "vga.h"
 
 static struct kthread *currentThread;
+static struct kthread *threadWithTimeout;
 
 void kthreadExit()
 {
@@ -36,6 +37,7 @@ int kthreadSetup(vaddr_t mainStack, size_t mainStackSize)
     current->state = RUNNING;
 
     list_singleton(currentThread, current);
+    list_init_named(threadWithTimeout, timePrev, timeNext);
 
     return 0;
 }
@@ -47,7 +49,9 @@ struct kthread *kthreadCreate(const char *name, cpu_kstate_function_arg1_t func,
         return NULL;
 
     thread->stackAddr = (vaddr_t)malloc(KTHREAD_DEFAULT_STACK_SIZE);
+#ifdef DEBUG
     printf("Alloc stask at 0x%x struct at 0x%x\n", thread->stackAddr, thread);
+#endif
     thread->stackSize = KTHREAD_DEFAULT_STACK_SIZE;
 
     if (!thread->stackAddr)
@@ -102,13 +106,18 @@ struct kthread *kthreadSelectNext()
 struct cpu_state *kthreadSwitch(struct cpu_state *prevCpu)
 {
     uint32_t flags;
+    struct kthread *nextThread;
+
     disable_IRQs(flags);
+
+    nextThread              = kthreadSelectNext();
     currentThread->cpuState = prevCpu;
     currentThread->state    = READY;
-    struct kthread *nextThread = kthreadSelectNext();
     currentThread           = nextThread;
     currentThread->state    = RUNNING;
+
     restore_IRQs(flags);
+
     return nextThread->cpuState;
 }
 
@@ -127,6 +136,17 @@ int kthreadOnJieffiesTick()
             }
         }
     }
+    list_foreach_named(threadWithTimeout, nextThread, idx, timePrev, timeNext)
+    {
+        if (nextThread->state == WAITING && nextThread->jiffiesSleeping) {
+            nextThread->jiffiesSleeping--;
+            if (!nextThread->jiffiesSleeping) {
+                nextThread->sleepHaveTimeouted = 1;
+                list_delete_named(threadWithTimeout, nextThread, timePrev, timeNext);
+                kthreadAddThread(nextThread);
+            }
+        }
+    }
     restore_IRQs(flags);
     return 0;
 }
@@ -138,29 +158,27 @@ int kthreadUnsched(struct kthread *th)
     return 0;
 }
 
-int kthreadSaveAndYield(struct kthread *current)
+// Must be called with IRQ disabled
+int kthreadWait(struct kthread *current, struct kthread *next, unsigned long msec)
 {
-    uint32_t flags;
-
-    disable_IRQs(flags);
-    struct kthread *next = kthreadSelectNext();
-
     if (current == next) {
-        restore_IRQs(flags);
+        assertmsg(0, "Cannot yield from %s to %s\n", current->name, next->name);
         return 0;
     }
 
     assertmsg(next->state == READY, "thread %s is in state %d\n", next->name, next->state);
 
-    if (current->state == RUNNING)
-        current->state = READY;
+    current->jiffiesSleeping    = msecs_to_jiffies(msec);
+    current->sleepHaveTimeouted = 0;
+
+    if (current->jiffiesSleeping)
+        list_add_tail_named(threadWithTimeout, current, timePrev, timeNext);
 
     currentThread        = next;
     currentThread->state = RUNNING;
     cpu_context_switch(&current->cpuState, next->cpuState);
-    restore_IRQs(flags);
 
-    return 0;
+    return current->sleepHaveTimeouted;
 }
 
 int kthreadYield()
@@ -202,6 +220,7 @@ int kthreadMsleep(unsigned long msec)
               current->state, msec);
 
     current->state              = SLEEPING;
+    current->sleepHaveTimeouted = 0;
     current->jiffiesSleeping    = msecs_to_jiffies(msec);
     next                        = kthreadSelectNext();
 
@@ -211,9 +230,8 @@ int kthreadMsleep(unsigned long msec)
     currentThread        = next;
     currentThread->state = RUNNING;
     cpu_context_switch(&current->cpuState, next->cpuState);
-
     restore_IRQs(flags);
-    return 0;
+    return current->sleepHaveTimeouted == 1;
 }
 
 struct kthread *getCurrentThread()

core/kthread.h

@@ -22,8 +22,11 @@ struct kthread {
     vaddr_t stackAddr;
     size_t stackSize;
     unsigned long jiffiesSleeping;
+    int sleepHaveTimeouted;
     struct kthread *next;
     struct kthread *prev;
+    struct kthread *timeNext;
+    struct kthread *timePrev;
 };
 
 int kthreadSetup(vaddr_t mainStack, size_t mainStackSize);
@@ -36,9 +39,9 @@ struct kthread *kthreadSelectNext();
 struct cpu_state *kthreadSwitch(struct cpu_state *prevCpu);
 
 int kthreadYield();
-int kthreadSaveAndYield(struct kthread *);
+int kthreadWait(struct kthread *current, struct kthread *next, unsigned long msec);
+int kthreadUnsched(struct kthread *th);
 int kthreadMsleep(unsigned long msec);
 int kthreadOnJieffiesTick();
 struct kthread *getCurrentThread();
 int kthreadAddThread(struct kthread *th);
-int kthreadUnsched(struct kthread *th);

core/wait.c

@@ -1,7 +1,7 @@
-#include "wait.h"
 #include "irq.h"
 #include "kthread.h"
 #include "list.h"
+#include "wait.h"
 
 int wake_up(struct wait_queue *wq)
 {
@@ -21,17 +21,25 @@ int wake_up(struct wait_queue *wq)
 
 int wait(struct wait_queue *wq)
 {
-    struct kthread *current;
+    return waitTimeout(wq, 0);
+}
+
+int waitTimeout(struct wait_queue *wq, unsigned long msec)
+{
+    struct kthread *current, *next;
     uint32_t flags;
+    int ret;
 
     disable_IRQs(flags);
 
     current = getCurrentThread();
-    kthreadUnsched(current);
-    list_add_tail(wq->thread, current);
     current->state = WAITING;
-    kthreadSaveAndYield(current);
+    next = kthreadSelectNext();
+    kthreadUnsched(current);
+
+    list_add_tail(wq->thread, current);
+    ret = kthreadWait(current, next, msec);
 
     restore_IRQs(flags);
-    return 0;
+    return ret;
 }

core/wait.h

@@ -8,7 +8,16 @@ struct wait_queue {
     struct wait_queue *prev;
 };
 
+#define __WAITQUEUE_INITIALIZER(name)                                                         \
+    {                                                                                         \
+        .thread = NULL, .next = NULL, .prev = NULL                                            \
+    }
+
+#define DECLARE_WAITQUEUE(name)					\
+	struct wait_queue name = __WAITQUEUE_INITIALIZER(name)
+
 int wait(struct wait_queue *);
+int waitTimeout(struct wait_queue *wq, unsigned long msec);
 int wake_up(struct wait_queue *);
 
 #define wait_event(wq, condition)                                                             \