struggling with new multitasking

1 files changed, 44 insertions, 98 deletions

diff --git a/kernel/task.c b/kernel/task.c
index 08301cf..620977e 100644
--- a/kernel/task.c
+++ b/kernel/task.c
@@ -14,75 +14,27 @@
 #include "fs/ext2.h"
 #define FOOLOS_MODULE_NAME "task"
 
-int started;
-static volatile int c1,c2,c3;
 
-void task_test1()
-{
-    // simple built-in shell
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"spawning build-in shell");
-
-   while(1)
-   {
-    
-	char c;
-	if(ringbuffer_get(&c))
-	{
-	    console_put_char_white(c);
-	}
-    }
-
-    /*
-	c1++;
-	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"task 1 progress: %d", c1);
-	sleep(2);
-	*/
-
-   
-
-}
+#define MAX_TASKS 10
 
-void task_test2()
-{
-   while(1)
-   {
-       c2++;
-       //log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"task 2 progress: %d", c2);
-//	sleep(2);
-
-   }
+static volatile int current_task=-2;
 
-}
-
-void task_test3()
+static volatile struct task_list_struct
 {
-   while(1)
-   {
-       c3++;
-//	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"task 3 progress: %d", c3);
-//	sleep(2);
-   }
-
-}
-
-//////////////
-//
-typedef struct{        //Simple structure for a thread
-      unsigned int esp0;   //Stack for kernel
-        unsigned int esp3;   //Stack for process
-} Thread;
-
-
-Thread Threads[3];     //Space for our simple threads.
-volatile int CurrentTask;  //The thread currenlty running (-1 == none) 
+    bool active;
+    uint32_t esp; // stack pointer of the task;
+    uint32_t vmem; // number of virtual memory table to switch to
+    
+}task_list[MAX_TASKS];
 
 
 void task_create(int pid,void(*thread)())
 {
      unsigned int *stack;
 
-    Threads[pid].esp0 = pmmngr_alloc_block();
-    stack = (unsigned int*)Threads[pid].esp0+4095; //This makes a pointer to the stack for us
+    task_list[pid].esp = pmmngr_alloc_block();
+    stack = (unsigned int*)task_list[pid].esp+4095; //This makes a pointer to the stack for us
+
     log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"new task: stack: 0x%08X  thread: 0x%08X", stack, thread);
 
  //First, this stuff is pushed by the processor
@@ -108,60 +60,54 @@ void task_create(int pid,void(*thread)())
  *--stack = 0x10; //GS
  */
  
- Threads[pid].esp0 = (uint32_t)stack; //Update the stack pointer
-
+    task_list[pid].esp = (uint32_t)stack; //Update the stack pointer
+    task_list[pid].active=true;
 
 };
 
+// this gets called by our clock interrupt regularly!
 uint32_t task_switch_next(uint32_t oldesp)
 {
+    timer_tick();
 
-    //console_put_char('.');
-  timer_tick();
-  if(started!=0xabcde) return oldesp;
-  if(CurrentTask!=-1)Threads[CurrentTask].esp0=oldesp;
-
-  CurrentTask++;
-  if(CurrentTask>2)CurrentTask=0;
-
-  /*
-  log(
-    FOOLOS_MODULE_NAME,
-    FOOLOS_LOG_INFO,
-    "oldesp: 0x%08X saved / next task: %d (esp: 0x%08X) ",
-    oldesp, 
-    CurrentTask,
-    Threads[CurrentTask].esp0);
- 
-//  return oldesp;
-//  */
-
-  return Threads[CurrentTask].esp0; //Return new stack pointer to ASM
-}
+    if(current_task==-2)return oldesp;
+    if(current_task!=-1)task_list[current_task].esp=oldesp;
 
-void stack_trace(uint32_t *stack,int size)
-{
-    for(int i=size;i>=0;i--)
+    for(int i=0;i<MAX_TASKS;i++)
     {
-	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"stack: 0x%08X -> 0x%08X", stack, *stack);
-	stack++;
+	int pid=(current_task+1+i)%MAX_TASKS; // schedule round robin style
 
+	if(task_list[pid].active)
+	{
+	    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"switch from %d to pid: %d (0x%08X)", current_task,pid,task_list[pid].esp);
+	    current_task=pid;
+	    return task_list[pid].esp;
+	}
 
     }
-}
-
-void task_init()
-{
 
+    // if no task found retunr the old esp
+    return oldesp;
+}
 
-   CurrentTask=-1;
+volatile int c1,c2;
 
-   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"init multitasking.");
-   task_create(0,task_test1);
-   task_create(1,task_test2);
-   task_create(2,task_test3);
-   started=0xabcde;
+volatile void test1()
+{
+    c1++;
+   // syscall_write(1,">",1);
 }
 
+volatile void test2()
+{
+    c2++;
+  //  syscall_write(1,"<",1);
+}
+void task_init()
+{
+    task_create(1,test1);
+    task_create(2,test2);
+    current_task=-1;
+}