| /* phil_fiber.c - dining philosopher */ |
| |
| /* |
| * Copyright (c) 2011-2015 Wind River Systems, Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| #include <zephyr.h> |
| #include "phil.h" |
| |
| #ifdef CONFIG_NANOKERNEL |
| #define FORK(x) (&forks[x]) |
| #define TAKE(x) nano_fiber_sem_take(x, TICKS_UNLIMITED) |
| #define GIVE(x) nano_fiber_sem_give(x) |
| #else /* ! CONFIG_NANOKERNEL */ |
| #define FORK(x) forks[x] |
| #define TAKE(x) task_mutex_lock(x, TICKS_UNLIMITED) |
| #define GIVE(x) task_mutex_unlock(x) |
| #endif /* CONFIG_NANOKERNEL */ |
| |
| #define RANDDELAY(x) myDelay(((sys_tick_get_32() * ((x) + 1)) & 0x1f) + 1) |
| |
| #define PRINT(x, y) myPrint(x, y) |
| |
| #ifdef CONFIG_NANOKERNEL |
| /* externs */ |
| |
| extern struct nano_sem forks[N_PHILOSOPHERS]; |
| #else /* ! CONFIG_NANOKERNEL */ |
| kmutex_t forks[] = {forkMutex0, forkMutex1, forkMutex2, forkMutex3, forkMutex4, |
| forkMutex5}; |
| #endif /* CONFIG_NANOKERNEL */ |
| |
| /** |
| * |
| * @brief Print a philosophers state |
| * |
| * @param id Philosopher ID. |
| * @param str EATING or THINKING. |
| * |
| * @return N/A |
| */ |
| |
| static void myPrint(int id, char *str) |
| { |
| PRINTF("\x1b[%d;%dHPhilosopher %d %s\n", id + 1, 1, id, str); |
| } |
| |
| /** |
| * |
| * @brief Wait for a number of ticks to elapse |
| * |
| * @param ticks Number of ticks to delay. |
| * |
| * @return N/A |
| */ |
| |
| static void myDelay(int ticks) |
| { |
| #ifdef CONFIG_MICROKERNEL |
| task_sleep(ticks); |
| #else |
| struct nano_timer timer; |
| |
| nano_timer_init(&timer, (void *) 0); |
| nano_fiber_timer_start(&timer, ticks); |
| nano_fiber_timer_test(&timer, TICKS_UNLIMITED); |
| #endif |
| } |
| |
| /** |
| * |
| * @brief Entry point to a philosopher's thread |
| * |
| * This routine runs as a task in the microkernel environment |
| * and as a fiber in the nanokernel environment. |
| * |
| * @return N/A |
| */ |
| |
| void philEntry(void) |
| { |
| #ifdef CONFIG_NANOKERNEL |
| struct nano_sem *f1; /* fork #1 */ |
| struct nano_sem *f2; /* fork #2 */ |
| #else |
| kmutex_t f1; /* fork #1 */ |
| kmutex_t f2; /* fork #2 */ |
| #endif |
| static int myId; /* next philosopher ID */ |
| int pri = irq_lock(); /* interrupt lock level */ |
| int id = myId++; /* current philosopher ID */ |
| |
| irq_unlock(pri); |
| |
| /* always take the lowest fork first */ |
| if ((id+1) != N_PHILOSOPHERS) { |
| f1 = FORK(id); |
| f2 = FORK(id + 1); |
| } else { |
| f1 = FORK(0); |
| f2 = FORK(id); |
| } |
| |
| while (1) { |
| TAKE(f1); |
| TAKE(f2); |
| |
| PRINT(id, "EATING "); |
| RANDDELAY(id); |
| |
| GIVE(f2); |
| GIVE(f1); |
| |
| PRINT(id, "THINKING"); |
| RANDDELAY(id); |
| } |
| } |