2022-08-04 11:40:24 +08:00

110 lines
2.3 KiB
C

/*
* This file is part of open_agb_firm
* Copyright (C) 2021 derrek, profi200
*
* 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 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include "types.h"
#include "internal/list.h"
#include "internal/kernel_private.h"
#include "internal/util.h"
#include "internal/slabheap.h"
#include "internal/config.h"
typedef struct
{
const TaskCb *owner;
ListNode waitQueue;
} KMutex;
static SlabHeap g_mutexSlab = {0};
void _mutexSlabInit(void)
{
slabInit(&g_mutexSlab, sizeof(KMutex), MAX_MUTEXES);
}
// TODO: Test mutex with multiple cores.
KHandle createMutex(void)
{
KMutex *const kmutex = (KMutex*)slabAlloc(&g_mutexSlab);
kmutex->owner = NULL;
listInit(&kmutex->waitQueue);
return (KHandle)kmutex;
}
void deleteMutex(KHandle const kmutex)
{
KMutex *const mutex = (KMutex*)kmutex;
kernelLock();
waitQueueWakeN(&mutex->waitQueue, (u32)-1, KRES_HANDLE_DELETED, true);
slabFree(&g_mutexSlab, mutex);
}
KRes lockMutex(KHandle const kmutex)
{
KMutex *const mutex = (KMutex*)kmutex;
KRes res;
do
{
kernelLock();
if(UNLIKELY(mutex->owner != NULL))
{
res = waitQueueBlock(&mutex->waitQueue);
if(UNLIKELY(res != KRES_OK)) break;
}
else
{
mutex->owner = getCurrentTask();
kernelUnlock();
res = KRES_OK;
break;
}
} while(1);
return res;
}
// TODO: Test if it works and only unlocks if current task == owner.
KRes unlockMutex(KHandle const kmutex)
{
KMutex *const mutex = (KMutex*)kmutex;
KRes res = KRES_OK;
kernelLock();
if(LIKELY(mutex->owner != NULL))
{
if(LIKELY(mutex->owner == getCurrentTask()))
{
mutex->owner = NULL;
waitQueueWakeN(&mutex->waitQueue, 1, KRES_OK, true);
}
else res = KRES_NO_PERMISSIONS;
}
else kernelUnlock();
return res;
}