0,0 → 1,211 |
/* |
* Copyright (C) 2001-2004 Jakub Jermar |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - Redistributions in binary form must reproduce the above copyright |
* notice, this list of conditions and the following disclaimer in the |
* documentation and/or other materials provided with the distribution. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
*/ |
|
/** |
* @file timeout.c |
* @brief Timeout management functions. |
*/ |
|
#include <time/timeout.h> |
#include <typedefs.h> |
#include <arch/types.h> |
#include <config.h> |
#include <panic.h> |
#include <synch/spinlock.h> |
#include <func.h> |
#include <cpu.h> |
#include <arch/asm.h> |
#include <arch.h> |
|
|
/** Initialize timeouts |
* |
* Initialize kernel timeouts. |
* |
*/ |
void timeout_init(void) |
{ |
spinlock_initialize(&CPU->timeoutlock, "timeout_lock"); |
list_initialize(&CPU->timeout_active_head); |
} |
|
|
/** Reinitialize timeout |
* |
* Initialize all members except the lock. |
* |
* @param t Timeout to be initialized. |
* |
*/ |
void timeout_reinitialize(timeout_t *t) |
{ |
t->cpu = NULL; |
t->ticks = 0; |
t->handler = NULL; |
t->arg = NULL; |
link_initialize(&t->link); |
} |
|
|
/** Initialize timeout |
* |
* Initialize all members including the lock. |
* |
* @param t Timeout to be initialized. |
* |
*/ |
void timeout_initialize(timeout_t *t) |
{ |
spinlock_initialize(&t->lock, "timeout_t_lock"); |
timeout_reinitialize(t); |
} |
|
|
/** Register timeout |
* |
* Insert timeout handler f (with argument arg) |
* to timeout list and make it execute in |
* time microseconds (or slightly more). |
* |
* @param t Timeout structure. |
* @param time Number of usec in the future to execute |
* the handler. |
* @param f Timeout handler function. |
* @param arg Timeout handler argument. |
* |
*/ |
void timeout_register(timeout_t *t, __u64 time, timeout_handler_t f, void *arg) |
{ |
timeout_t *hlp = NULL; |
link_t *l, *m; |
ipl_t ipl; |
__u64 sum; |
|
ipl = interrupts_disable(); |
spinlock_lock(&CPU->timeoutlock); |
spinlock_lock(&t->lock); |
|
if (t->cpu) |
panic("t->cpu != 0"); |
|
t->cpu = CPU; |
t->ticks = us2ticks(time); |
|
t->handler = f; |
t->arg = arg; |
|
/* |
* Insert t into the active timeouts list according to t->ticks. |
*/ |
sum = 0; |
l = CPU->timeout_active_head.next; |
while (l != &CPU->timeout_active_head) { |
hlp = list_get_instance(l, timeout_t, link); |
spinlock_lock(&hlp->lock); |
if (t->ticks < sum + hlp->ticks) { |
spinlock_unlock(&hlp->lock); |
break; |
} |
sum += hlp->ticks; |
spinlock_unlock(&hlp->lock); |
l = l->next; |
} |
|
m = l->prev; |
list_prepend(&t->link, m); /* avoid using l->prev */ |
|
/* |
* Adjust t->ticks according to ticks accumulated in h's predecessors. |
*/ |
t->ticks -= sum; |
|
/* |
* Decrease ticks of t's immediate succesor by t->ticks. |
*/ |
if (l != &CPU->timeout_active_head) { |
spinlock_lock(&hlp->lock); |
hlp->ticks -= t->ticks; |
spinlock_unlock(&hlp->lock); |
} |
|
spinlock_unlock(&t->lock); |
spinlock_unlock(&CPU->timeoutlock); |
interrupts_restore(ipl); |
} |
|
|
/** Unregister timeout |
* |
* Remove timeout from timeout list. |
* |
* @param t Timeout to unregister. |
* |
* @return true on success, false on failure. |
*/ |
bool timeout_unregister(timeout_t *t) |
{ |
timeout_t *hlp; |
link_t *l; |
ipl_t ipl; |
|
grab_locks: |
ipl = interrupts_disable(); |
spinlock_lock(&t->lock); |
if (!t->cpu) { |
spinlock_unlock(&t->lock); |
interrupts_restore(ipl); |
return false; |
} |
if (!spinlock_trylock(&t->cpu->timeoutlock)) { |
spinlock_unlock(&t->lock); |
interrupts_restore(ipl); |
goto grab_locks; |
} |
|
/* |
* Now we know for sure that t hasn't been activated yet |
* and is lurking in t->cpu->timeout_active_head queue. |
*/ |
|
l = t->link.next; |
if (l != &t->cpu->timeout_active_head) { |
hlp = list_get_instance(l, timeout_t, link); |
spinlock_lock(&hlp->lock); |
hlp->ticks += t->ticks; |
spinlock_unlock(&hlp->lock); |
} |
|
list_remove(&t->link); |
spinlock_unlock(&t->cpu->timeoutlock); |
|
timeout_reinitialize(t); |
spinlock_unlock(&t->lock); |
|
interrupts_restore(ipl); |
return true; |
} |