newlib-cygwin/libgloss/sparc_leon/kernel_mutex.c

108 lines
2.9 KiB
C

/*
* Copyright (c) 2011 Aeroflex Gaisler
*
* BSD license:
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <asm-leon/queue.h>
/*#include <sys/fsu_pthread_queue.h>*/
#include <asm-leon/contextswitch.h>
#include <asm-leon/leonbare_kernel.h>
#include <asm-leon/leonbare_debug.h>
#include <asm-leon/stack.h>
#include <asm-leon/leonstack.h>
#include <asm-leon/irq.h>
leonbare_mutex_t
leonbare_mutex_init (leonbare_mutex_t m)
{
m->mx_owner_cnt = 0;
m->mx_owner = 0;
LBTAILQ_INIT (&(m->mx_threads));
LEONBARE_PROTECT_KERNEL_START ();
{
LBTAILQ_INSERT_TAIL (LEONBARE_KR_ALLM, m, mx_allm);
}
LEONBARE_PROTECT_KERNEL_END ();
}
int
_self__leonbare_mutex_lock (leonbare_mutex_t m, int wait)
{
int ret = LEONBARE_MUTEX_LOCK_OK;
leonbare_thread_t c;
LEONBARE_PROTECT_MUTEXSTRUCT_START (m);
while (1)
{
if (LEONBARE_MUTEX_OWNER_GET (m) == 0)
{
LEONBARE_MUTEX_OWNER_SET (m, LEONBARE_KR_CURRENT);
LEONBARE_MUTEX_OWNER_CNT_SET (m, 0);
LBTAILQ_INSERT_TAIL (&c->th_mutex_locked, m, mx_locked);
ret = LEONBARE_MUTEX_LOCK_OK;
break;
}
else if (m->mx_owner == LEONBARE_KR_CURRENT)
{
m->mx_owner_cnt++;
ret = LEONBARE_MUTEX_LOCK_OK;
break;
}
LBTAILQ_INSERT_TAIL (&m->mx_threads, c, th_mutex);
current_suspend ();
}
LEONBARE_PROTECT_MUTEXSTRUCT_END (m);
return ret;
}
int
leonbare_mutex_unlock (leonbare_mutex_t m)
{
int ret = LEONBARE_MUTEX_UNLOCK_ERROR;
leonbare_thread_t c, h;
LEONBARE_PROTECT_MUTEXSTRUCT_START (m);
{
c = LEONBARE_KR_CURRENT;
if (m->mx_owner != c)
{
ret = LEONBARE_MUTEX_UNLOCK_OK;
}
else if (m->mx_owner == c && m->mx_owner_cnt)
{
m->mx_owner_cnt--;
ret = LEONBARE_MUTEX_UNLOCK_OK;
}
else if ((h = LBTAILQ_FIRST (&m->mx_threads)))
{
LBTAILQ_REMOVE (&m->mx_threads, h, th_mutex);
leonbare_thread_resume (h);
ret = LEONBARE_MUTEX_UNLOCK_OK;
}
}
LEONBARE_PROTECT_MUTEXSTRUCT_END (m);
return ret;
}