- Add more strict in_atomic() checking to the mutex entry

function just to be extra safety and paranoid.

- Rewrite the thread shim to take full advantage of the
new kernel kthread API.  This greatly simplifies things.

- Add a new regression test for thread_exit() to ensure
it properly terminates a thread immediately without
allowing futher execution of the thread.



git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@69 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
This commit is contained in:
behlendo
2008-04-11 17:03:57 +00:00
parent 79f92663e3
commit 115aed0dd8
3 changed files with 123 additions and 73 deletions
+15 -46
View File
@@ -1,4 +1,5 @@
#include <sys/thread.h>
#include <sys/kmem.h>
/*
* Thread interfaces
@@ -10,9 +11,6 @@ typedef struct thread_priv_s {
size_t tp_len; /* Len to be passed to function */
int tp_state; /* State to start thread at */
pri_t tp_pri; /* Priority to start threat at */
volatile kthread_t *tp_task; /* Task pointer for new thread */
spinlock_t tp_lock; /* Syncronization lock */
wait_queue_head_t tp_waitq; /* Syncronization wait queue */
} thread_priv_t;
static int
@@ -22,21 +20,13 @@ thread_generic_wrapper(void *arg)
void (*func)(void *);
void *args;
spin_lock(&tp->tp_lock);
BUG_ON(tp->tp_magic != TP_MAGIC);
func = tp->tp_func;
args = tp->tp_args;
tp->tp_task = get_current();
set_current_state(tp->tp_state);
set_user_nice((kthread_t *)tp->tp_task, PRIO_TO_NICE(tp->tp_pri));
set_user_nice((kthread_t *)get_current(), PRIO_TO_NICE(tp->tp_pri));
kmem_free(arg, sizeof(thread_priv_t));
spin_unlock(&tp->tp_lock);
wake_up(&tp->tp_waitq);
/* DO NOT USE 'ARG' AFTER THIS POINT, EVER, EVER, EVER!
* Local variables are used here because after the calling thread
* has been woken up it will exit and this memory will no longer
* be safe to access since it was declared on the callers stack. */
if (func)
func(args);
@@ -59,7 +49,7 @@ __thread_create(caddr_t stk, size_t stksize, thread_func_t func,
const char *name, void *args, size_t len, int *pp,
int state, pri_t pri)
{
thread_priv_t tp;
thread_priv_t *tp;
DEFINE_WAIT(wait);
struct task_struct *tsk;
@@ -68,45 +58,24 @@ __thread_create(caddr_t stk, size_t stksize, thread_func_t func,
BUG_ON(stk != NULL);
BUG_ON(stk != 0);
/* Variable tp is located on the stack and not the heap because I want
* to minimize any chance of a failure, since the Solaris code is designed
* such that this function cannot fail. This is a little dangerous since
* we're passing a stack address to a new thread but correct locking was
* added to ensure the callee can use the data safely until wake_up(). */
tp.tp_magic = TP_MAGIC;
tp.tp_func = func;
tp.tp_args = args;
tp.tp_len = len;
tp.tp_state = state;
tp.tp_pri = pri;
tp.tp_task = NULL;
spin_lock_init(&tp.tp_lock);
init_waitqueue_head(&tp.tp_waitq);
tp = kmem_alloc(sizeof(thread_priv_t), KM_SLEEP);
if (tp == NULL)
return NULL;
spin_lock(&tp.tp_lock);
tp->tp_magic = TP_MAGIC;
tp->tp_func = func;
tp->tp_args = args;
tp->tp_len = len;
tp->tp_state = state;
tp->tp_pri = pri;
tsk = kthread_create(thread_generic_wrapper, (void *)&tp, "%s", name);
tsk = kthread_create(thread_generic_wrapper, (void *)tp, "%s", name);
if (IS_ERR(tsk)) {
printk("spl: Failed to create thread: %ld\n", PTR_ERR(tsk));
return NULL;
}
wake_up_process(tsk);
/* All signals are ignored due to sleeping TASK_UNINTERRUPTIBLE */
for (;;) {
prepare_to_wait(&tp.tp_waitq, &wait, TASK_UNINTERRUPTIBLE);
if (tp.tp_task != NULL)
break;
spin_unlock(&tp.tp_lock);
schedule();
spin_lock(&tp.tp_lock);
}
BUG_ON(tsk != tp.tp_task); /* Extra paranoia */
spin_unlock(&tp.tp_lock);
return (kthread_t *)tp.tp_task;
return (kthread_t *)tsk;
}
EXPORT_SYMBOL(__thread_create);