[PATCH] usbatm: use kthread_ API

From: Christoph Hellwig
Date: Tue Feb 14 2006 - 12:49:51 EST


Use the kthread_ API instead of opencoding lots of hairy code for kernel
thread creation and teardown.

Note: due to the short thread runtime we don't need a
kthread_should_stop()

Note2: all this is a bit odd and I don't have hardware, Duncan or David,
could you give it a try?


Signed-off-by: Christoph Hellwig <hch@xxxxxx>

Index: linux-2.6/drivers/usb/atm/usbatm.c
===================================================================
--- linux-2.6.orig/drivers/usb/atm/usbatm.c 2006-02-04 13:35:01.000000000 +0100
+++ linux-2.6/drivers/usb/atm/usbatm.c 2006-02-14 18:08:04.000000000 +0100
@@ -75,6 +75,7 @@
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
+#include <linux/kthread.h>
#include <linux/signal.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
@@ -999,38 +1000,24 @@
struct usbatm_data *instance = arg;
int ret;

- daemonize(instance->driver->driver_name);
- allow_signal(SIGTERM);
-
- complete(&instance->thread_started);
-
ret = instance->driver->heavy_init(instance, instance->usb_intf);
-
if (!ret)
ret = usbatm_atm_init(instance);
-
- mutex_lock(&instance->serialize);
- instance->thread_pid = -1;
- mutex_unlock(&instance->serialize);
-
- complete_and_exit(&instance->thread_exited, ret);
+ return 0;
}

static int usbatm_heavy_init(struct usbatm_data *instance)
{
- int ret = kernel_thread(usbatm_do_heavy_init, instance, CLONE_KERNEL);
+ int ret;

- if (ret < 0) {
- usb_err(instance, "%s: failed to create kernel_thread (%d)!\n", __func__, ret);
+ instance->thread = kthread_run(usbatm_do_heavy_init, instance, "%s",
+ instance->driver->driver_name);
+ if (IS_ERR(instance->thread)) {
+ ret = PTR_ERR(instance->thread);
+ usb_err(instance, "%s: failed to create kernel thread (%d)!\n", __func__, ret);
return ret;
}

- mutex_lock(&instance->serialize);
- instance->thread_pid = ret;
- mutex_unlock(&instance->serialize);
-
- wait_for_completion(&instance->thread_started);
-
return 0;
}

@@ -1112,10 +1099,6 @@
kref_init(&instance->refcount); /* dropped in usbatm_usb_disconnect */
mutex_init(&instance->serialize);

- instance->thread_pid = -1;
- init_completion(&instance->thread_started);
- init_completion(&instance->thread_exited);
-
INIT_LIST_HEAD(&instance->vcc_list);
skb_queue_head_init(&instance->sndqueue);

@@ -1227,7 +1210,6 @@
if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) {
error = usbatm_heavy_init(instance);
} else {
- complete(&instance->thread_exited); /* pretend that heavy_init was run */
error = usbatm_atm_init(instance);
}

@@ -1275,12 +1257,10 @@

mutex_lock(&instance->serialize);
instance->disconnected = 1;
- if (instance->thread_pid >= 0)
- kill_proc(instance->thread_pid, SIGTERM, 1);
+ if (instance->thread);
+ kthread_stop(instance->thread);
mutex_unlock(&instance->serialize);

- wait_for_completion(&instance->thread_exited);
-
mutex_lock(&instance->serialize);
list_for_each_entry(vcc_data, &instance->vcc_list, list)
vcc_release_async(vcc_data->vcc, -EPIPE);
Index: linux-2.6/drivers/usb/atm/usbatm.h
===================================================================
--- linux-2.6.orig/drivers/usb/atm/usbatm.h 2006-02-04 13:35:01.000000000 +0100
+++ linux-2.6/drivers/usb/atm/usbatm.h 2006-02-14 18:07:11.000000000 +0100
@@ -176,9 +176,7 @@
int disconnected;

/* heavy init */
- int thread_pid;
- struct completion thread_started;
- struct completion thread_exited;
+ struct task_struct *thread;

/* ATM device */
struct list_head vcc_list;

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/