[Bluetooth] Convert RFCOMM to use kthread API

This patch does the full kthread conversion for the RFCOMM protocol. It
makes the code slightly simpler and more maintainable.

Based on a patch from Christoph Hellwig <hch@lst.de>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index bb7220770f2c671c879cca9aecdb3404021323a4..e7ac6ba7ecab0391829956d3bc97ad756a2c3800 100644 (file)
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -33,11 +33,11 @@
 #include <linux/sched.h>
 #include <linux/signal.h>
 #include <linux/init.h>
-#include <linux/freezer.h>
 #include <linux/wait.h>
 #include <linux/device.h>
 #include <linux/net.h>
 #include <linux/mutex.h>
+#include <linux/kthread.h>
 
 #include <net/sock.h>
 #include <asm/uaccess.h>
@@ -68,7 +68,6 @@ static DEFINE_MUTEX(rfcomm_mutex);
 static unsigned long rfcomm_event;
 
 static LIST_HEAD(session_list);
-static atomic_t terminate, running;
 
 static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len);
 static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci);
@@ -1850,26 +1849,6 @@ static inline void rfcomm_process_sessions(void)
        rfcomm_unlock();
 }
 
-static void rfcomm_worker(void)
-{
-       BT_DBG("");
-
-       while (!atomic_read(&terminate)) {
-               set_current_state(TASK_INTERRUPTIBLE);
-               if (!test_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event)) {
-                       /* No pending events. Let's sleep.
-                        * Incoming connections and data will wake us up. */
-                       schedule();
-               }
-               set_current_state(TASK_RUNNING);
-
-               /* Process stuff */
-               clear_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event);
-               rfcomm_process_sessions();
-       }
-       return;
-}
-
 static int rfcomm_add_listener(bdaddr_t *ba)
 {
        struct sockaddr_l2 addr;
@@ -1935,22 +1914,28 @@ static void rfcomm_kill_listener(void)
 
 static int rfcomm_run(void *unused)
 {
-       rfcomm_thread = current;
-
-       atomic_inc(&running);
+       BT_DBG("");
 
-       daemonize("krfcommd");
        set_user_nice(current, -10);
 
-       BT_DBG("");
-
        rfcomm_add_listener(BDADDR_ANY);
 
-       rfcomm_worker();
+       while (!kthread_should_stop()) {
+               set_current_state(TASK_INTERRUPTIBLE);
+               if (!test_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event)) {
+                       /* No pending events. Let's sleep.
+                        * Incoming connections and data will wake us up. */
+                       schedule();
+               }
+               set_current_state(TASK_RUNNING);
+
+               /* Process stuff */
+               clear_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event);
+               rfcomm_process_sessions();
+       }
 
        rfcomm_kill_listener();
 
-       atomic_dec(&running);
        return 0;
 }
 
@@ -2059,7 +2044,11 @@ static int __init rfcomm_init(void)
 
        hci_register_cb(&rfcomm_cb);
 
-       kernel_thread(rfcomm_run, NULL, CLONE_KERNEL);
+       rfcomm_thread = kthread_run(rfcomm_run, NULL, "krfcommd");
+       if (IS_ERR(rfcomm_thread)) {
+               hci_unregister_cb(&rfcomm_cb);
+               return PTR_ERR(rfcomm_thread);
+       }
 
        if (class_create_file(bt_class, &class_attr_rfcomm_dlc) < 0)
                BT_ERR("Failed to create RFCOMM info file");
@@ -2081,14 +2070,7 @@ static void __exit rfcomm_exit(void)
 
        hci_unregister_cb(&rfcomm_cb);
 
-       /* Terminate working thread.
-        * ie. Set terminate flag and wake it up */
-       atomic_inc(&terminate);
-       rfcomm_schedule(RFCOMM_SCHED_STATE);
-
-       /* Wait until thread is running */
-       while (atomic_read(&running))
-               schedule();
+       kthread_stop(rfcomm_thread);
 
 #ifdef CONFIG_BT_RFCOMM_TTY
        rfcomm_cleanup_ttys();