Simplify sched: Use only a single task list.

[paraslash.git] / sched.c

diff --git a/sched.c b/sched.c
index d42e149801e4a7ecabd4f96cc1f79802eb7a4ff1..86069029f2820a4844fd296a423617a95ae0b4c5 100644 (file)
--- a/sched.c
+++ b/sched.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2006-2013 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2014 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -21,25 +21,6 @@
 static struct timeval now_struct;
 struct timeval *now = &now_struct;
 
-/*
- * Remove a task from the scheduler.
- *
- * \param t The task to remove.
- *
- * If the pre_select pointer of \a t is not \p NULL, it is removed from
- * the pre_select list of the scheduler. Same goes for \a post_select.
- */
-static void unregister_task(struct task *t)
-{
-       assert(t->error < 0);
-       PARA_INFO_LOG("unregistering %s (%s)\n", t->status,
-               para_strerror(-t->error));
-       if (t->pre_select)
-               list_del(&t->pre_select_node);
-       if (t->post_select)
-               list_del(&t->post_select_node);
-}
-
 static inline bool timeout_is_zero(struct sched *s)
 {
        struct timeval *tv = &s->select_timeout;
@@ -50,7 +31,9 @@ static void sched_preselect(struct sched *s)
 {
        struct task *t, *tmp;
 
-       list_for_each_entry_safe(t, tmp, &s->pre_select_list, pre_select_node) {
+       list_for_each_entry_safe(t, tmp, &s->task_list, node) {
+               if (t->error < 0)
+                       continue;
                if (t->notification != 0)
                        sched_min_delay(s);
                if (t->pre_select)
@@ -82,19 +65,16 @@ static void sched_post_select(struct sched *s)
 {
        struct task *t, *tmp;
 
-       list_for_each_entry_safe(t, tmp, &s->post_select_list, post_select_node) {
-               if (t->error >= 0)
-                       call_post_select(s, t);
-//             PARA_INFO_LOG("%s: %d\n", t->status, t->ret);
+       list_for_each_entry_safe(t, tmp, &s->task_list, node) {
+               call_post_select(s, t);
                t->notification = 0;
-               if (t->error >= 0)
-                       continue;
-               unregister_task(t);
+               if (t->error < 0)
+                       list_del(&t->node);
        }
 }
 
 /**
- * The core function for all paraslash programs.
+ * The core function of all paraslash programs.
  *
  * \param s Pointer to the scheduler struct.
  *
@@ -103,10 +83,10 @@ static void sched_post_select(struct sched *s)
  * the fd sets of \a s.  Next, it calls para_select() and makes the result available
  * to the registered tasks by calling their post_select hook.
  *
- * \return Zero if no more tasks are left in either of the two lists, negative
- * if para_select returned an error.
+ * \return Zero if no more tasks are left in the task list, negative if the
+ * select function returned an error.
  *
- * \sa task, now.
+ * \sa \ref task, \ref now.
  */
 int schedule(struct sched *s)
 {
@@ -137,7 +117,7 @@ again:
        }
        clock_get_realtime(now);
        sched_post_select(s);
-       if (list_empty(&s->pre_select_list) && list_empty(&s->post_select_list))
+       if (list_empty(&s->task_list))
                return 0;
        goto again;
 }
@@ -148,27 +128,16 @@ again:
  * \param t The task to add.
  * \param s The scheduler instance to add the task to.
  *
- * If the pre_select pointer of \a t is not \p NULL, it is added to
- * the pre_select list of the scheduler. Same goes for post_select.
- *
  * \sa task::pre_select, task::post_select
  */
 void register_task(struct sched *s, struct task *t)
 {
        PARA_INFO_LOG("registering %s (%p)\n", t->status, t);
+       assert(t->post_select);
        t->notification = 0;
-       if (!s->pre_select_list.next)
-               INIT_LIST_HEAD(&s->pre_select_list);
-       if (!s->post_select_list.next)
-               INIT_LIST_HEAD(&s->post_select_list);
-       if (t->pre_select) {
-               PARA_DEBUG_LOG("pre_select: %p\n", &t->pre_select);
-               list_add_tail(&t->pre_select_node, &s->pre_select_list);
-       }
-       if (t->post_select) {
-               PARA_DEBUG_LOG("post_select: %p\n", &t->post_select);
-               list_add_tail(&t->post_select_node, &s->post_select_list);
-       }
+       if (!s->task_list.next)
+               INIT_LIST_HEAD(&s->task_list);
+       list_add_tail(&t->node, &s->task_list);
 }
 
 /**
@@ -186,21 +155,12 @@ char *get_task_list(struct sched *s)
        struct task *t, *tmp;
        char *msg = NULL;
 
-       list_for_each_entry_safe(t, tmp, &s->pre_select_list, pre_select_node) {
-               char *tmp_msg;
-               tmp_msg = make_message("%s%p\tpre\t%s\n", msg? msg : "", t, t->status);
-               free(msg);
-               msg = tmp_msg;
-       }
-       list_for_each_entry_safe(t, tmp, &s->post_select_list, post_select_node) {
+       list_for_each_entry_safe(t, tmp, &s->task_list, node) {
                char *tmp_msg;
-//             if (t->pre_select)
-//                     continue;
-               tmp_msg = make_message("%s%p\tpost\t%s\n", msg? msg : "", t, t->status);
+               tmp_msg = make_message("%s%p\t%s\n", msg? msg : "", t, t->status);
                free(msg);
                msg = tmp_msg;
        }
-       //PARA_DEBUG_LOG("task list:\n%s", msg);
        return msg;
 }
 
@@ -261,9 +221,7 @@ void task_notify_all(struct sched *s, int err)
 {
        struct task *t;
 
-       list_for_each_entry(t, &s->pre_select_list, pre_select_node)
-               task_notify(t, err);
-       list_for_each_entry(t, &s->post_select_list, post_select_node)
+       list_for_each_entry(t, &s->task_list, node)
                task_notify(t, err);
 }