0,0 → 1,219 |
/* |
* Copyright (c) 2009 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. |
*/ |
|
/** @addtogroup libc |
* @{ |
*/ |
/** @file |
*/ |
|
#include <fibril_sync.h> |
#include <fibril.h> |
#include <async.h> |
#include <adt/list.h> |
#include <futex.h> |
#include <assert.h> |
|
void fibril_mutex_initialize(fibril_mutex_t *fm) |
{ |
fm->counter = 1; |
list_initialize(&fm->waiters); |
} |
|
void fibril_mutex_lock(fibril_mutex_t *fm) |
{ |
futex_down(&async_futex); |
if (fm->counter-- <= 0) { |
fibril_t *f = (fibril_t *) fibril_get_id(); |
list_append(&f->link, &fm->waiters); |
fibril_switch(FIBRIL_TO_MANAGER); |
} else { |
futex_up(&async_futex); |
} |
} |
|
bool fibril_mutex_trylock(fibril_mutex_t *fm) |
{ |
bool locked = false; |
|
futex_down(&async_futex); |
if (fm->counter > 0) { |
fm->counter--; |
locked = true; |
} |
futex_up(&async_futex); |
|
return locked; |
} |
|
static void _fibril_mutex_unlock_unsafe(fibril_mutex_t *fm) |
{ |
assert(fm->counter <= 0); |
if (fm->counter++ < 0) { |
link_t *tmp; |
fibril_t *f; |
|
assert(!list_empty(&fm->waiters)); |
tmp = fm->waiters.next; |
f = list_get_instance(tmp, fibril_t, link); |
list_remove(&f->link); |
fibril_add_ready((fid_t) f); |
} |
} |
|
void fibril_mutex_unlock(fibril_mutex_t *fm) |
{ |
futex_down(&async_futex); |
_fibril_mutex_unlock_unsafe(fm); |
futex_up(&async_futex); |
} |
|
void fibril_rwlock_initialize(fibril_rwlock_t *frw) |
{ |
frw->writers = 0; |
frw->readers = 0; |
list_initialize(&frw->waiters); |
} |
|
void fibril_rwlock_read_lock(fibril_rwlock_t *frw) |
{ |
futex_down(&async_futex); |
if (frw->writers) { |
fibril_t *f = (fibril_t *) fibril_get_id(); |
f->flags &= ~FIBRIL_WRITER; |
list_append(&f->link, &frw->waiters); |
fibril_switch(FIBRIL_TO_MANAGER); |
} else { |
frw->readers++; |
futex_up(&async_futex); |
} |
} |
|
void fibril_rwlock_write_lock(fibril_rwlock_t *frw) |
{ |
futex_down(&async_futex); |
if (frw->writers || frw->readers) { |
fibril_t *f = (fibril_t *) fibril_get_id(); |
f->flags |= FIBRIL_WRITER; |
list_append(&f->link, &frw->waiters); |
fibril_switch(FIBRIL_TO_MANAGER); |
} else { |
frw->writers++; |
futex_up(&async_futex); |
} |
} |
|
static void _fibril_rwlock_common_unlock(fibril_rwlock_t *frw) |
{ |
futex_down(&async_futex); |
assert(frw->readers || (frw->writers == 1)); |
if (frw->readers) { |
if (--frw->readers) |
goto out; |
} else { |
frw->writers--; |
} |
|
assert(!frw->readers && !frw->writers); |
|
while (!list_empty(&frw->waiters)) { |
link_t *tmp = frw->waiters.next; |
fibril_t *f = list_get_instance(tmp, fibril_t, link); |
|
if (f->flags & FIBRIL_WRITER) { |
if (frw->readers) |
break; |
list_remove(&f->link); |
fibril_add_ready((fid_t) f); |
frw->writers++; |
break; |
} else { |
list_remove(&f->link); |
fibril_add_ready((fid_t) f); |
frw->readers++; |
} |
} |
out: |
futex_up(&async_futex); |
} |
|
void fibril_rwlock_read_unlock(fibril_rwlock_t *frw) |
{ |
_fibril_rwlock_common_unlock(frw); |
} |
|
void fibril_rwlock_write_unlock(fibril_rwlock_t *frw) |
{ |
_fibril_rwlock_common_unlock(frw); |
} |
|
void fibril_condvar_initialize(fibril_condvar_t *fcv) |
{ |
list_initialize(&fcv->waiters); |
} |
|
void fibril_condvar_wait(fibril_condvar_t *fcv, fibril_mutex_t *fm) |
{ |
fibril_t *f = (fibril_t *) fibril_get_id(); |
|
futex_down(&async_futex); |
list_append(&f->link, &fcv->waiters); |
_fibril_mutex_unlock_unsafe(fm); |
fibril_switch(FIBRIL_TO_MANAGER); |
fibril_mutex_lock(fm); |
} |
|
static void _fibril_condvar_wakeup_common(fibril_condvar_t *fcv, bool once) |
{ |
link_t *tmp; |
fibril_t *f; |
|
futex_down(&async_futex); |
while (!list_empty(&fcv->waiters)) { |
tmp = fcv->waiters.next; |
f = list_get_instance(tmp, fibril_t, link); |
list_remove(&f->link); |
fibril_add_ready((fid_t) f); |
if (once) |
break; |
} |
futex_up(&async_futex); |
} |
|
void fibril_condvar_signal(fibril_condvar_t *fcv) |
{ |
_fibril_condvar_wakeup_common(fcv, true); |
} |
|
void fibril_condvar_broadcast(fibril_condvar_t *fcv) |
{ |
_fibril_condvar_wakeup_common(fcv, false); |
} |
|
/** @} |
*/ |