summaryrefslogtreecommitdiffstats
path: root/net/rxrpc/krxtimod.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/rxrpc/krxtimod.c')
-rw-r--r--net/rxrpc/krxtimod.c203
1 files changed, 203 insertions, 0 deletions
diff --git a/net/rxrpc/krxtimod.c b/net/rxrpc/krxtimod.c
new file mode 100644
index 000000000000..249c2b0290bb
--- /dev/null
+++ b/net/rxrpc/krxtimod.c
@@ -0,0 +1,203 @@
+/* krxtimod.c: RXRPC timeout daemon
+ *
+ * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <rxrpc/rxrpc.h>
+#include <rxrpc/krxtimod.h>
+#include <asm/errno.h>
+#include "internal.h"
+
+static DECLARE_COMPLETION(krxtimod_alive);
+static DECLARE_COMPLETION(krxtimod_dead);
+static DECLARE_WAIT_QUEUE_HEAD(krxtimod_sleepq);
+static int krxtimod_die;
+
+static LIST_HEAD(krxtimod_list);
+static DEFINE_SPINLOCK(krxtimod_lock);
+
+static int krxtimod(void *arg);
+
+/*****************************************************************************/
+/*
+ * start the timeout daemon
+ */
+int rxrpc_krxtimod_start(void)
+{
+ int ret;
+
+ ret = kernel_thread(krxtimod, NULL, 0);
+ if (ret < 0)
+ return ret;
+
+ wait_for_completion(&krxtimod_alive);
+
+ return ret;
+} /* end rxrpc_krxtimod_start() */
+
+/*****************************************************************************/
+/*
+ * stop the timeout daemon
+ */
+void rxrpc_krxtimod_kill(void)
+{
+ /* get rid of my daemon */
+ krxtimod_die = 1;
+ wake_up(&krxtimod_sleepq);
+ wait_for_completion(&krxtimod_dead);
+
+} /* end rxrpc_krxtimod_kill() */
+
+/*****************************************************************************/
+/*
+ * timeout processing daemon
+ */
+static int krxtimod(void *arg)
+{
+ DECLARE_WAITQUEUE(myself, current);
+
+ rxrpc_timer_t *timer;
+
+ printk("Started krxtimod %d\n", current->pid);
+
+ daemonize("krxtimod");
+
+ complete(&krxtimod_alive);
+
+ /* loop around looking for things to attend to */
+ loop:
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&krxtimod_sleepq, &myself);
+
+ for (;;) {
+ unsigned long jif;
+ signed long timeout;
+
+ /* deal with the server being asked to die */
+ if (krxtimod_die) {
+ remove_wait_queue(&krxtimod_sleepq, &myself);
+ _leave("");
+ complete_and_exit(&krxtimod_dead, 0);
+ }
+
+ try_to_freeze(PF_FREEZE);
+
+ /* discard pending signals */
+ rxrpc_discard_my_signals();
+
+ /* work out the time to elapse before the next event */
+ spin_lock(&krxtimod_lock);
+ if (list_empty(&krxtimod_list)) {
+ timeout = MAX_SCHEDULE_TIMEOUT;
+ }
+ else {
+ timer = list_entry(krxtimod_list.next,
+ rxrpc_timer_t, link);
+ timeout = timer->timo_jif;
+ jif = jiffies;
+
+ if (time_before_eq((unsigned long) timeout, jif))
+ goto immediate;
+
+ else {
+ timeout = (long) timeout - (long) jiffies;
+ }
+ }
+ spin_unlock(&krxtimod_lock);
+
+ schedule_timeout(timeout);
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+
+ /* the thing on the front of the queue needs processing
+ * - we come here with the lock held and timer pointing to the expired
+ * entry
+ */
+ immediate:
+ remove_wait_queue(&krxtimod_sleepq, &myself);
+ set_current_state(TASK_RUNNING);
+
+ _debug("@@@ Begin Timeout of %p", timer);
+
+ /* dequeue the timer */
+ list_del_init(&timer->link);
+ spin_unlock(&krxtimod_lock);
+
+ /* call the timeout function */
+ timer->ops->timed_out(timer);
+
+ _debug("@@@ End Timeout");
+ goto loop;
+
+} /* end krxtimod() */
+
+/*****************************************************************************/
+/*
+ * (re-)queue a timer
+ */
+void rxrpc_krxtimod_add_timer(rxrpc_timer_t *timer, unsigned long timeout)
+{
+ struct list_head *_p;
+ rxrpc_timer_t *ptimer;
+
+ _enter("%p,%lu", timer, timeout);
+
+ spin_lock(&krxtimod_lock);
+
+ list_del(&timer->link);
+
+ /* the timer was deferred or reset - put it back in the queue at the
+ * right place */
+ timer->timo_jif = jiffies + timeout;
+
+ list_for_each(_p, &krxtimod_list) {
+ ptimer = list_entry(_p, rxrpc_timer_t, link);
+ if (time_before(timer->timo_jif, ptimer->timo_jif))
+ break;
+ }
+
+ list_add_tail(&timer->link, _p); /* insert before stopping point */
+
+ spin_unlock(&krxtimod_lock);
+
+ wake_up(&krxtimod_sleepq);
+
+ _leave("");
+} /* end rxrpc_krxtimod_add_timer() */
+
+/*****************************************************************************/
+/*
+ * dequeue a timer
+ * - returns 0 if the timer was deleted or -ENOENT if it wasn't queued
+ */
+int rxrpc_krxtimod_del_timer(rxrpc_timer_t *timer)
+{
+ int ret = 0;
+
+ _enter("%p", timer);
+
+ spin_lock(&krxtimod_lock);
+
+ if (list_empty(&timer->link))
+ ret = -ENOENT;
+ else
+ list_del_init(&timer->link);
+
+ spin_unlock(&krxtimod_lock);
+
+ wake_up(&krxtimod_sleepq);
+
+ _leave(" = %d", ret);
+ return ret;
+} /* end rxrpc_krxtimod_del_timer() */