[SPARC]: Use kthread infrastructure in envctrl

envctrl currently uses very odd ways to stop a thread, using various
things that should be exposed to drivers at all.

This patch (which is untested as I don't have sparc hardware) switches
it to use the proper kthread infrastructure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 31 deletions

diff --git a/drivers/sbus/char/envctrl.c b/drivers/sbus/char/envctrl.c
index 9a8c572554f5..e103b12f9efe 100644
--- a/drivers/sbus/char/envctrl.c
+++ b/drivers/sbus/char/envctrl.c
@@ -24,6 +24,7 @@
 #include <linux/config.h>
 #include <linux/module.h>
 #include <linux/sched.h>
+#include <linux/kthread.h>
 #include <linux/errno.h>
 #include <linux/delay.h>
 #include <linux/ioport.h>
@@ -1010,16 +1011,13 @@ static int kenvctrld(void *__unused)
 
         poll_interval = 5000; /* TODO env_mon_interval */
 
-        daemonize("kenvctrld");
-        allow_signal(SIGKILL);
-
-        kenvctrld_task = current;
-
         printk(KERN_INFO "envctrl: %s starting...\n", current->comm);
         for (;;) {
-                if(msleep_interruptible(poll_interval))
-                        break;
+                msleep_interruptible(poll_interval);
 
+                if (kthread_should_stop())
+                        break;
+                
                 for (whichcpu = 0; whichcpu < ENVCTRL_MAX_CPU; ++whichcpu) {
                         if (0 < envctrl_read_cpu_info(whichcpu, cputemp,
                                                       ENVCTRL_CPUTEMP_MON,
@@ -1118,9 +1116,11 @@ done:
                         i2c_childlist[i].addr, (0 == i) ? ("\n") : (" "));
         }
 
-        err = kernel_thread(kenvctrld, NULL, CLONE_FS | CLONE_FILES);
-        if (err < 0)
+        kenvctrld_task = kthread_run(kenvctrld, NULL, "kenvctrld");
+        if (IS_ERR(kenvctrld_task)) {
+                err = ERR_PTR(kenvctrld_task);
                 goto out_deregister;
+        }
 
         return 0;
 
@@ -1142,28 +1142,7 @@ static void __exit envctrl_cleanup(void)
 {
         int i;
 
-        if (NULL != kenvctrld_task) {
-                force_sig(SIGKILL, kenvctrld_task);
-                for (;;) {
-                        struct task_struct *p;
-                        int found = 0;
-
-                        read_lock(&tasklist_lock);
-                        for_each_process(p) {
-                                if (p == kenvctrld_task) {
-                                        found = 1;
-                                        break;
-                                }
-                        }
-                        read_unlock(&tasklist_lock);
-
-                        if (!found)
-                                break;
-
-                        msleep(1000);
-                }
-                kenvctrld_task = NULL;
-        }
+        kthread_stop(kenvctrld_task);
 
         iounmap(i2c);
         misc_deregister(&envctrl_dev);