| /* |
| * RT-Mutex-tester: scriptable tester for rt mutexes |
| * |
| * started by Thomas Gleixner: |
| * |
| * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com> |
| * |
| */ |
| #include <linux/kthread.h> |
| #include <linux/module.h> |
| #include <linux/sched.h> |
| #include <linux/smp_lock.h> |
| #include <linux/spinlock.h> |
| #include <linux/sysdev.h> |
| #include <linux/timer.h> |
| |
| #include "rtmutex.h" |
| |
| #define MAX_RT_TEST_THREADS 8 |
| #define MAX_RT_TEST_MUTEXES 8 |
| |
| static spinlock_t rttest_lock; |
| static atomic_t rttest_event; |
| |
| struct test_thread_data { |
| int opcode; |
| int opdata; |
| int mutexes[MAX_RT_TEST_MUTEXES]; |
| int bkl; |
| int event; |
| struct sys_device sysdev; |
| }; |
| |
| static struct test_thread_data thread_data[MAX_RT_TEST_THREADS]; |
| static struct task_struct *threads[MAX_RT_TEST_THREADS]; |
| static struct rt_mutex mutexes[MAX_RT_TEST_MUTEXES]; |
| |
| enum test_opcodes { |
| RTTEST_NOP = 0, |
| RTTEST_SCHEDOT, /* 1 Sched other, data = nice */ |
| RTTEST_SCHEDRT, /* 2 Sched fifo, data = prio */ |
| RTTEST_LOCK, /* 3 Lock uninterruptible, data = lockindex */ |
| RTTEST_LOCKNOWAIT, /* 4 Lock uninterruptible no wait in wakeup, data = lockindex */ |
| RTTEST_LOCKINT, /* 5 Lock interruptible, data = lockindex */ |
| RTTEST_LOCKINTNOWAIT, /* 6 Lock interruptible no wait in wakeup, data = lockindex */ |
| RTTEST_LOCKCONT, /* 7 Continue locking after the wakeup delay */ |
| RTTEST_UNLOCK, /* 8 Unlock, data = lockindex */ |
| RTTEST_LOCKBKL, /* 9 Lock BKL */ |
| RTTEST_UNLOCKBKL, /* 10 Unlock BKL */ |
| RTTEST_SIGNAL, /* 11 Signal other test thread, data = thread id */ |
| RTTEST_RESETEVENT = 98, /* 98 Reset event counter */ |
| RTTEST_RESET = 99, /* 99 Reset all pending operations */ |
| }; |
| |
| static int handle_op(struct test_thread_data *td, int lockwakeup) |
| { |
| int i, id, ret = -EINVAL; |
| |
| switch(td->opcode) { |
| |
| case RTTEST_NOP: |
| return 0; |
| |
| case RTTEST_LOCKCONT: |
| td->mutexes[td->opdata] = 1; |
| td->event = atomic_add_return(1, &rttest_event); |
| return 0; |
| |
| case RTTEST_RESET: |
| for (i = 0; i < MAX_RT_TEST_MUTEXES; i++) { |
| if (td->mutexes[i] == 4) { |
| rt_mutex_unlock(&mutexes[i]); |
| td->mutexes[i] = 0; |
| } |
| } |
| |
| if (!lockwakeup && td->bkl == 4) { |
| unlock_kernel(); |
| td->bkl = 0; |
| } |
| return 0; |
| |
| case RTTEST_RESETEVENT: |
| atomic_set(&rttest_event, 0); |
| return 0; |
| |
| default: |
| if (lockwakeup) |
| return ret; |
| } |
| |
| switch(td->opcode) { |
| |
| case RTTEST_LOCK: |
| case RTTEST_LOCKNOWAIT: |
| id = td->opdata; |
| if (id < 0 || id >= MAX_RT_TEST_MUTEXES) |
| return ret; |
| |
| td->mutexes[id] = 1; |
| td->event = atomic_add_return(1, &rttest_event); |
| rt_mutex_lock(&mutexes[id]); |
| td->event = atomic_add_return(1, &rttest_event); |
| td->mutexes[id] = 4; |
| return 0; |
| |
| case RTTEST_LOCKINT: |
| case RTTEST_LOCKINTNOWAIT: |
| id = td->opdata; |
| if (id < 0 || id >= MAX_RT_TEST_MUTEXES) |
| return ret; |
| |
| td->mutexes[id] = 1; |
| td->event = atomic_add_return(1, &rttest_event); |
| ret = rt_mutex_lock_interruptible(&mutexes[id], 0); |
| td->event = atomic_add_return(1, &rttest_event); |
| td->mutexes[id] = ret ? 0 : 4; |
| return ret ? -EINTR : 0; |
| |
| case RTTEST_UNLOCK: |
| id = td->opdata; |
| if (id < 0 || id >= MAX_RT_TEST_MUTEXES || td->mutexes[id] != 4) |
| return ret; |
| |
| td->event = atomic_add_return(1, &rttest_event); |
| rt_mutex_unlock(&mutexes[id]); |
| td->event = atomic_add_return(1, &rttest_event); |
| td->mutexes[id] = 0; |
| return 0; |
| |
| case RTTEST_LOCKBKL: |
| if (td->bkl) |
| return 0; |
| td->bkl = 1; |
| lock_kernel(); |
| td->bkl = 4; |
| return 0; |
| |
| case RTTEST_UNLOCKBKL: |
| if (td->bkl != 4) |
| break; |
| unlock_kernel(); |
| td->bkl = 0; |
| return 0; |
| |
| default: |
| break; |
| } |
| return ret; |
| } |
| |
| /* |
| * Schedule replacement for rtsem_down(). Only called for threads with |
| * PF_MUTEX_TESTER set. |
| * |
| * This allows us to have finegrained control over the event flow. |
| * |
| */ |
| void schedule_rt_mutex_test(struct rt_mutex *mutex) |
| { |
| int tid, op, dat; |
| struct test_thread_data *td; |
| |
| /* We have to lookup the task */ |
| for (tid = 0; tid < MAX_RT_TEST_THREADS; tid++) { |
| if (threads[tid] == current) |
| break; |
| } |
| |
| BUG_ON(tid == MAX_RT_TEST_THREADS); |
| |
| td = &thread_data[tid]; |
| |
| op = td->opcode; |
| dat = td->opdata; |
| |
| switch (op) { |
| case RTTEST_LOCK: |
| case RTTEST_LOCKINT: |
| case RTTEST_LOCKNOWAIT: |
| case RTTEST_LOCKINTNOWAIT: |
| if (mutex != &mutexes[dat]) |
| break; |
| |
| if (td->mutexes[dat] != 1) |
| break; |
| |
| td->mutexes[dat] = 2; |
| td->event = atomic_add_return(1, &rttest_event); |
| break; |
| |
| case RTTEST_LOCKBKL: |
| default: |
| break; |
| } |
| |
| schedule(); |
| |
| |
| switch (op) { |
| case RTTEST_LOCK: |
| case RTTEST_LOCKINT: |
| if (mutex != &mutexes[dat]) |
| return; |
| |
| if (td->mutexes[dat] != 2) |
| return; |
| |
| td->mutexes[dat] = 3; |
| td->event = atomic_add_return(1, &rttest_event); |
| break; |
| |
| case RTTEST_LOCKNOWAIT: |
| case RTTEST_LOCKINTNOWAIT: |
| if (mutex != &mutexes[dat]) |
| return; |
| |
| if (td->mutexes[dat] != 2) |
| return; |
| |
| td->mutexes[dat] = 1; |
| td->event = atomic_add_return(1, &rttest_event); |
| return; |
| |
| case RTTEST_LOCKBKL: |
| return; |
| default: |
| return; |
| } |
| |
| td->opcode = 0; |
| |
| for (;;) { |
| set_current_state(TASK_INTERRUPTIBLE); |
| |
| if (td->opcode > 0) { |
| int ret; |
| |
| set_current_state(TASK_RUNNING); |
| ret = handle_op(td, 1); |
| set_current_state(TASK_INTERRUPTIBLE); |
| if (td->opcode == RTTEST_LOCKCONT) |
| break; |
| td->opcode = ret; |
| } |
| |
| /* Wait for the next command to be executed */ |
| schedule(); |
| } |
| |
| /* Restore previous command and data */ |
| td->opcode = op; |
| td->opdata = dat; |
| } |
| |
| static int test_func(void *data) |
| { |
| struct test_thread_data *td = data; |
| int ret; |
| |
| current->flags |= PF_MUTEX_TESTER; |
| allow_signal(SIGHUP); |
| |
| for(;;) { |
| |
| set_current_state(TASK_INTERRUPTIBLE); |
| |
| if (td->opcode > 0) { |
| set_current_state(TASK_RUNNING); |
| ret = handle_op(td, 0); |
| set_current_state(TASK_INTERRUPTIBLE); |
| td->opcode = ret; |
| } |
| |
| /* Wait for the next command to be executed */ |
| schedule(); |
| try_to_freeze(); |
| |
| if (signal_pending(current)) |
| flush_signals(current); |
| |
| if(kthread_should_stop()) |
| break; |
| } |
| return 0; |
| } |
| |
| /** |
| * sysfs_test_command - interface for test commands |
| * @dev: thread reference |
| * @buf: command for actual step |
| * @count: length of buffer |
| * |
| * command syntax: |
| * |
| * opcode:data |
| */ |
| static ssize_t sysfs_test_command(struct sys_device *dev, const char *buf, |
| size_t count) |
| { |
| struct sched_param schedpar; |
| struct test_thread_data *td; |
| char cmdbuf[32]; |
| int op, dat, tid, ret; |
| |
| td = container_of(dev, struct test_thread_data, sysdev); |
| tid = td->sysdev.id; |
| |
| /* strings from sysfs write are not 0 terminated! */ |
| if (count >= sizeof(cmdbuf)) |
| return -EINVAL; |
| |
| /* strip of \n: */ |
| if (buf[count-1] == '\n') |
| count--; |
| if (count < 1) |
| return -EINVAL; |
| |
| memcpy(cmdbuf, buf, count); |
| cmdbuf[count] = 0; |
| |
| if (sscanf(cmdbuf, "%d:%d", &op, &dat) != 2) |
| return -EINVAL; |
| |
| switch (op) { |
| case RTTEST_SCHEDOT: |
| schedpar.sched_priority = 0; |
| ret = sched_setscheduler(threads[tid], SCHED_NORMAL, &schedpar); |
| if (ret) |
| return ret; |
| set_user_nice(current, 0); |
| break; |
| |
| case RTTEST_SCHEDRT: |
| schedpar.sched_priority = dat; |
| ret = sched_setscheduler(threads[tid], SCHED_FIFO, &schedpar); |
| if (ret) |
| return ret; |
| break; |
| |
| case RTTEST_SIGNAL: |
| send_sig(SIGHUP, threads[tid], 0); |
| break; |
| |
| default: |
| if (td->opcode > 0) |
| return -EBUSY; |
| td->opdata = dat; |
| td->opcode = op; |
| wake_up_process(threads[tid]); |
| } |
| |
| return count; |
| } |
| |
| /** |
| * sysfs_test_status - sysfs interface for rt tester |
| * @dev: thread to query |
| * @buf: char buffer to be filled with thread status info |
| */ |
| static ssize_t sysfs_test_status(struct sys_device *dev, char *buf) |
| { |
| struct test_thread_data *td; |
| struct task_struct *tsk; |
| char *curr = buf; |
| int i; |
| |
| td = container_of(dev, struct test_thread_data, sysdev); |
| tsk = threads[td->sysdev.id]; |
| |
| spin_lock(&rttest_lock); |
| |
| curr += sprintf(curr, |
| "O: %4d, E:%8d, S: 0x%08lx, P: %4d, N: %4d, B: %p, K: %d, M:", |
| td->opcode, td->event, tsk->state, |
| (MAX_RT_PRIO - 1) - tsk->prio, |
| (MAX_RT_PRIO - 1) - tsk->normal_prio, |
| tsk->pi_blocked_on, td->bkl); |
| |
| for (i = MAX_RT_TEST_MUTEXES - 1; i >=0 ; i--) |
| curr += sprintf(curr, "%d", td->mutexes[i]); |
| |
| spin_unlock(&rttest_lock); |
| |
| curr += sprintf(curr, ", T: %p, R: %p\n", tsk, |
| mutexes[td->sysdev.id].owner); |
| |
| return curr - buf; |
| } |
| |
| static SYSDEV_ATTR(status, 0600, sysfs_test_status, NULL); |
| static SYSDEV_ATTR(command, 0600, NULL, sysfs_test_command); |
| |
| static struct sysdev_class rttest_sysclass = { |
| set_kset_name("rttest"), |
| }; |
| |
| static int init_test_thread(int id) |
| { |
| thread_data[id].sysdev.cls = &rttest_sysclass; |
| thread_data[id].sysdev.id = id; |
| |
| threads[id] = kthread_run(test_func, &thread_data[id], "rt-test-%d", id); |
| if (IS_ERR(threads[id])) |
| return PTR_ERR(threads[id]); |
| |
| return sysdev_register(&thread_data[id].sysdev); |
| } |
| |
| static int init_rttest(void) |
| { |
| int ret, i; |
| |
| spin_lock_init(&rttest_lock); |
| |
| for (i = 0; i < MAX_RT_TEST_MUTEXES; i++) |
| rt_mutex_init(&mutexes[i]); |
| |
| ret = sysdev_class_register(&rttest_sysclass); |
| if (ret) |
| return ret; |
| |
| for (i = 0; i < MAX_RT_TEST_THREADS; i++) { |
| ret = init_test_thread(i); |
| if (ret) |
| break; |
| ret = sysdev_create_file(&thread_data[i].sysdev, &attr_status); |
| if (ret) |
| break; |
| ret = sysdev_create_file(&thread_data[i].sysdev, &attr_command); |
| if (ret) |
| break; |
| } |
| |
| printk("Initializing RT-Tester: %s\n", ret ? "Failed" : "OK" ); |
| |
| return ret; |
| } |
| |
| device_initcall(init_rttest); |