WebSVN – HelenOS-historic – Diff – //kernel/trunk/generic/src/proc/scheduler.c

 #include <print.h>
 #include <debug.h>
 atomic_t nrdy;
-/** Take actions before new thread runs
+/** Take actions before new thread runs.
+ *
  * Perform actions that need to be
  * taken before the newly selected
  * tread is passed control.
+ *
         THREAD->fpu_context_exists=1;
+    }
 #endif
+}
+/** Take actions after old thread ran.
+ *
+ * Perform actions that need to be
+ * taken after the running thread
+ * was preempted by the scheduler.
+ *
+ * THREAD->lock is locked on entry
+ *
+ */
+void after_thread_ran(void)
+{
+    after_thread_ran_arch();
+}
 #ifdef CONFIG_FPU_LAZY
 void scheduler_fpu_lazy_request(void)
+{
     fpu_enable();
     spinlock_lock(&CPU->lock);
     int priority;
     ASSERT(CPU != NULL);
     if (THREAD) {
+        /* must be run after switch to scheduler stack */
+        after_thread_ran();
         switch (THREAD->state) {
             case Running:
             THREAD->state = Ready;
             spinlock_unlock(&THREAD->lock);
             thread_ready(THREAD);
              * Entering state is unexpected.
              */
             panic("tid%d: unexpected state %s\n", THREAD->tid, thread_states[THREAD->state]);
             break;
+        }
         THREAD = NULL;
+    }
     THREAD = find_best_thread();
     #ifdef SCHEDULER_VERBOSE
     printf("cpu%d: tid %d (priority=%d,ticks=%d,nrdy=%d)\n", CPU->id, THREAD->tid, THREAD->priority, THREAD->ticks, atomic_get(&CPU->nrdy));
     #endif
     /*
+     * Some architectures provide late kernel PA2KA(identity)
+     * mapping in a page fault handler. However, the page fault
+     * handler uses the kernel stack of the running thread and
+     * therefore cannot be used to map it. The kernel stack, if
+     * necessary, is to be mapped in before_thread_runs(). This
+     * function must be executed before the switch to the new stack.
+     */
+    before_thread_runs();
+    /*
      * Copy the knowledge of CPU, TASK, THREAD and preemption counter to thread's stack.
      */
     the_copy(THE, (the_t *) THREAD->kstack);
     context_restore(&THREAD->saved_context);
 #endif
         if (!context_save(&THREAD->saved_context)) {
             /*
              * This is the place where threads leave scheduler();
              */
-            before_thread_runs();
             spinlock_unlock(&THREAD->lock);
             interrupts_restore(THREAD->saved_context.ipl);
             return;
+        }

Subversion Repositories HelenOS-historic

(root)//kernel/trunk/generic/src/proc/scheduler.c – Rev 827 → 897