X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Fkern%2Fproc.c;h=acaf4220a1bdd3527f274762096b648f65ecac20;hb=4cedc580e66cca972b055b9002ccadada6d5da75;hp=18c89599eb689dcce8344ef5be7a9af626f669d2;hpb=e62f2f13f13bca63f05e8ce92c945dcadb0f712f;p=bertos.git

diff --git a/bertos/kern/proc.c b/bertos/kern/proc.c
index 18c89599..acaf4220 100644
--- a/bertos/kern/proc.c
+++ b/bertos/kern/proc.c
@@ -85,7 +85,7 @@ static struct Process main_process;
 /**
  * Local heap dedicated to allocate the memory used by the processes.
  */
-static HEAP_DEFINE_BUF(heap_buf, KERN_MINSTACKSIZE * 128);
+static HEAP_DEFINE_BUF(heap_buf, CONFIG_KERN_HEAP_SIZE);
 static Heap proc_heap;
 
 /*
@@ -139,11 +139,6 @@ void proc_init(void)
 	monitor_init();
 	monitor_add(current_process, "main");
 #endif
-
-#if CONFIG_KERN_PREEMPT
-	preempt_init();
-#endif
-
 	MOD_INIT(proc);
 }
 
@@ -425,11 +420,40 @@ void proc_exit(void)
 	ASSERT(0);
 }
 
-
 /**
- * Get the pointer to the user data of the current process
+ * Call the scheduler and eventually replace the current running process.
  */
-iptr_t proc_currentUserData(void)
+void proc_schedule(void)
 {
-	return current_process->user_data;
+	Process *old_process = current_process;
+
+	IRQ_ASSERT_DISABLED();
+
+	/* Poll on the ready queue for the first ready process */
+	LIST_ASSERT_VALID(&proc_ready_list);
+	while (!(current_process = (struct Process *)list_remHead(&proc_ready_list)))
+	{
+		/*
+		 * Make sure we physically reenable interrupts here, no matter what
+		 * the current task status is. This is important because if we
+		 * are idle-spinning, we must allow interrupts, otherwise no
+		 * process will ever wake up.
+		 *
+		 * During idle-spinning, an interrupt can occur and it may
+		 * modify \p proc_ready_list. To ensure that compiler reload this
+		 * variable every while cycle we call CPU_MEMORY_BARRIER.
+		 * The memory barrier ensure that all variables used in this context
+		 * are reloaded.
+		 * \todo If there was a way to write sig_wait() so that it does not
+		 * disable interrupts while waiting, there would not be any
+		 * reason to do this.
+		 */
+		IRQ_ENABLE;
+		CPU_IDLE;
+		MEMORY_BARRIER;
+		IRQ_DISABLE;
+	}
+	proc_switchTo(current_process, old_process);
+	/* This RET resumes the execution on the new process */
+	LOG_INFO("resuming %p:%s\n", current_process, proc_currentName());
 }