X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=sched.c;h=86069029f2820a4844fd296a423617a95ae0b4c5;hp=e67579b32339c17101bbe2e3cedc45c9410cc7bc;hb=00cedf20a69178ac3ec3e43035a2d54868f1bc6d;hpb=58ce610c5a46eb03810d8a93b10d5bc51bc10b12 diff --git a/sched.c b/sched.c index e67579b3..86069029 100644 --- a/sched.c +++ b/sched.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2006-2012 Andre Noll + * Copyright (C) 2006-2014 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -8,7 +8,6 @@ #include #include -#include #include "para.h" #include "ipc.h" @@ -22,25 +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; @@ -50,20 +30,14 @@ static inline bool timeout_is_zero(struct sched *s) 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) { - if (t->error < 0) { - unregister_task(t); + + list_for_each_entry_safe(t, tmp, &s->task_list, node) { + if (t->error < 0) continue; - } - if (t->notification != 0) { + if (t->notification != 0) sched_min_delay(s); - break; - } - if (!t->pre_select) - continue; - t->pre_select(s, t); - if (timeout_is_zero(s)) - break; + if (t->pre_select) + t->pre_select(s, t); } } @@ -71,14 +45,14 @@ static void sched_preselect(struct sched *s) static inline void call_post_select(struct sched *s, struct task *t) { #ifndef SCHED_DEBUG - t->post_select(s, t); + t->error = t->post_select(s, t); #else struct timeval t1, t2, diff; unsigned long pst; - gettimeofday(&t1, NULL); - t->post_select(s, t); - gettimeofday(&t2, NULL); + clock_get_realtime(&t1); + t->error = t->post_select(s, t); + clock_get_realtime(&t2); tv_diff(&t1, &t2, &diff); pst = tv2ms(&diff); if (pst > 50) @@ -91,27 +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; - /* - * We have to check whether the list is empty because the call - * to ->post_select() might have called sched_shutdown(). In - * this case t has been unregistered already, so we must not - * unregister it again. - */ - if (list_empty(&s->post_select_list)) - return; - 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. * @@ -120,10 +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) { @@ -136,32 +99,25 @@ again: FD_ZERO(&s->wfds); s->select_timeout = s->default_timeout; s->max_fileno = -1; - gettimeofday(now, NULL); + clock_get_realtime(now); sched_preselect(s); - if (list_empty(&s->pre_select_list) && list_empty(&s->post_select_list)) - return 0; - if (!timeout_is_zero(s)) { - ret = s->select_function(s->max_fileno + 1, &s->rfds, &s->wfds, - &s->select_timeout); - if (ret < 0) - return ret; - if (ret == 0) { - /* - * APUE: Be careful not to check the descriptor sets on return - * unless the return value is greater than zero. The return - * state of the descriptor sets is implementation dependent if - * either a signal is caught or the timer expires. - */ - FD_ZERO(&s->rfds); - FD_ZERO(&s->wfds); - } - gettimeofday(now, NULL); - } else { + ret = s->select_function(s->max_fileno + 1, &s->rfds, &s->wfds, + &s->select_timeout); + if (ret < 0) + return ret; + if (ret == 0) { + /* + * APUE: Be careful not to check the descriptor sets on return + * unless the return value is greater than zero. The return + * state of the descriptor sets is implementation dependent if + * either a signal is caught or the timer expires. + */ FD_ZERO(&s->rfds); FD_ZERO(&s->wfds); } + 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; } @@ -172,50 +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); - } -} - -/** - * Unregister all tasks. - * - * \param s The scheduler instance to shut down. - * - * This will cause \a schedule() to return immediately because both the - * \a pre_select_list and the \a post_select_list are empty. This function - * must be called from the post_select (rather than the pre_select) method. - */ -void sched_shutdown(struct sched *s) -{ - struct task *t, *tmp; - - list_for_each_entry_safe(t, tmp, &s->pre_select_list, pre_select_node) { - t->error = -E_SCHED_SHUTDOWN; - unregister_task(t); - } - list_for_each_entry_safe(t, tmp, &s->post_select_list, post_select_node) { - t->error = -E_SCHED_SHUTDOWN; - unregister_task(t); - } + if (!s->task_list.next) + INIT_LIST_HEAD(&s->task_list); + list_add_tail(&t->node, &s->task_list); } /** @@ -233,21 +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) { + list_for_each_entry_safe(t, tmp, &s->task_list, node) { char *tmp_msg; - tmp_msg = make_message("%s%p\tpre\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; } - list_for_each_entry_safe(t, tmp, &s->post_select_list, post_select_node) { - char *tmp_msg; -// if (t->pre_select) -// continue; - tmp_msg = make_message("%s%p\tpost\t%s\n", msg? msg : "", t, t->status); - free(msg); - msg = tmp_msg; - } - //PARA_DEBUG_LOG("task list:\n%s", msg); return msg; } @@ -295,6 +208,23 @@ int task_get_notification(struct task *t) return t->notification; } +/** + * Set the notification value of all tasks of a scheduler instance. + * + * \param s The scheduler instance whose tasks should be notified. + * \param err A positive error code. + * + * This simply iterates over all existing tasks of \a s and sets each + * task's notification value to \p -err. + */ +void task_notify_all(struct sched *s, int err) +{ + struct task *t; + + list_for_each_entry(t, &s->task_list, node) + task_notify(t, err); +} + /** * Set the select timeout to the minimal possible value. *