preempt: irq supervisor draft

[bertos.git] / bertos / kern / preempt.c

diff --git a/bertos/kern/preempt.c b/bertos/kern/preempt.c
index ab3fc7a8f7db005e5f1e3f2c8623b8647a6a737e..339dc09fe089e8e00e7e38b5e77c04a412f22016 100644 (file)
--- a/bertos/kern/preempt.c
+++ b/bertos/kern/preempt.c
@@ -26,8 +26,7 @@
  * invalidate any other reasons why the executable file might be covered by
  * the GNU General Public License.
  *
- * Copyright 2001, 2004 Develer S.r.l. (http://www.develer.com/)
- * Copyright 1999, 2000, 2001, 2008 Bernie Innocenti <bernie@codewiz.org>
+ * Copyright 2008 Bernie Innocenti <bernie@codewiz.org>
  * -->
  *
  * \brief Simple realtime multitasking scheduler.
@@ -35,15 +34,13 @@
  *
  * \version $Id: proc.c 1616 2008-08-10 19:41:26Z bernie $
  * \author Bernie Innocenti <bernie@codewiz.org>
- * \author Stefano Fedrigo <aleph@develer.com>
  */
 
 #include "proc_p.h"
 #include "proc.h"
 
 #include <cpu/frame.h> // CPU_IDLE
-
-#include <unistd.h> // XXX alarm()
+#include <drv/timer.h>
 
 
 /*
@@ -52,6 +49,8 @@
  */
 uint16_t Quantum;
 
+Timer preempt_timer;
+
 /**
  * Disable preemptive task switching.
  *
@@ -97,7 +96,7 @@ void proc_preempt(void)
        /* Poll on the ready queue for the first ready process */
        while (!(CurrentProcess = (struct Process *)list_remHead(&ProcReadyList)))
        {
-       TRACEMSG("hello2");
+       //TRACEMSG("hello2");
                /*
                 * Make sure we physically reenable interrupts here, no matter what
                 * the current task status is. This is important because if we
@@ -114,24 +113,26 @@ void proc_preempt(void)
                //FIXME: calls Qt stuff from sighandler! CPU_IDLE;
                MEMORY_BARRIER;
                IRQ_DISABLE;
-       TRACEMSG("hello3");
+       //TRACEMSG("hello3");
        }
        IRQ_ENABLE;
        TRACEMSG("hello4");
 }
 
-void proc_preempt_timer(void)
+void proc_preempt_timer(UNUSED_ARG(void *, param))
 {
-       // TODO: check Quantum
-
-       alarm(1);
-
+       IRQ_DISABLE;
        if (CurrentProcess)
        {
                TRACEMSG("preempting %p:%s", CurrentProcess, CurrentProcess->monitor.name);
-               ATOMIC(SCHED_ENQUEUE(CurrentProcess));
-               proc_schedule();
+               SCHED_ENQUEUE(CurrentProcess);
+               IRQ_ENABLE;
+               proc_preempt();
        }
+       IRQ_ENABLE;
+
+       timer_setDelay(&preempt_timer, CONFIG_KERN_QUANTUM);
+       timer_add(&preempt_timer);
 }
 
 void proc_schedule(void)
@@ -158,51 +159,60 @@ void proc_entry(void (*user_entry)(void))
 /* signal handler */
 void irq_entry(int signum)
 {
-       Process *old_process;
-
-//     TRACEMSG("storing %p:%s", CurrentProcess, CurrentProcess->monitor.name);
-//     CurrentProcess->leaving = false;
-//     getcontext(&CurrentProcess->context);
-       /* We get here in two ways: directly, and after setcontext() below */
-
-//     if (CurrentProcess->leaving)
-//     {
-//             TRACEMSG("leaving to %p:%s", CurrentProcess, CurrentProcess->monitor.name);
-//             return;
-//     }
-
-       old_process = CurrentProcess;
+       Process * const old_process = CurrentProcess;
 
        irq_handlers[signum]();
 
-       if (old_process != CurrentProcess)
+       if (!CurrentProcess)
        {
-               TRACEMSG("switching from %p:%s to %p:%s",
-                       old_process, old_process->monitor.name,
-                       CurrentProcess, CurrentProcess->monitor.name);
-               swapcontext(&old_process->context, &CurrentProcess->context);
-//             TRACEMSG("launching %p:%s", CurrentProcess, CurrentProcess->monitor.name);
-//             CurrentProcess->leaving = true;
-//             setcontext(&CurrentProcess->context);
-               /* not reached */
+               TRACEMSG("no runnable processes!");
+               IRQ_ENABLE;
+               pause();
+       }
+       else
+       {
+               if (old_process != CurrentProcess)
+               {
+                       TRACEMSG("switching from %p:%s to %p:%s",
+                               old_process, old_process ? old_process->monitor.name : "-",
+                               CurrentProcess, CurrentProcess->monitor.name);
+
+                       if (old_process)
+                               swapcontext(&old_process->context, &CurrentProcess->context);
+                       else
+                               setcontext(&CurrentProcess->context);
+
+                       /* not reached */
+               }
+               TRACEMSG("keeping %p:%s", CurrentProcess, CurrentProcess->monitor.name);
        }
+}
 
-       TRACEMSG("keeping %p:%s", CurrentProcess, CurrentProcess->monitor.name);
+void irq_register(int irq, void (*callback)(void))
+{
+       irq_handlers[irq] = callback;
 }
 
-void preempt_init(void)
+void irq_init(void)
 {
        struct sigaction act;
        act.sa_handler = irq_entry;
        sigemptyset(&act.sa_mask);
-       sigaddset(&act.sa_mask, SIGUSR1);
-       sigaddset(&act.sa_mask, SIGALRM);
+       //sigaddset(&act.sa_mask, irq);
        act.sa_flags = SA_RESTART; /* | SA_SIGINFO; */
 
-       irq_handlers[SIGUSR1] = proc_preempt;
-       irq_handlers[SIGALRM] = proc_preempt_timer;
        sigaction(SIGUSR1, &act, NULL);
-       sigaction(SIGALRM, &act, NULL);
+       #if !(ARCH & ARCH_QT)
+               sigaction(SIGALRM, &act, NULL);
+       #endif
+}
+
+void preempt_init(void)
+{
+       irq_init(); // FIXME: move before
+       irq_register(SIGUSR1, proc_preempt);
 
-       alarm(1);  // FIXME
+       timer_setSoftInt(&preempt_timer, proc_preempt_timer, NULL);
+       timer_setDelay(&preempt_timer, CONFIG_KERN_QUANTUM);
+       timer_add(&preempt_timer);
 }