Staging: rt2870: Removal of kernel_thread() API

Replacing the use of kernel_thread() with kthread_run().   But as
kthread_run() returned a task structure, as compared with
kernel_thread() returning a PID, it was found to be more efficient to
store the task structure pointer as a field data instead of PID
pointer.   On top of modifying the field to store task structure
pointer, the initialization of the field (assigned to
THREAD_PID_INIT_VALUE) was also found unnecessary - as no where it is
found to be used.


Signed-off-by: Peter Teoh <htmldeveloper@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

7 files changed, 53 insertions, 74 deletions

diff --git a/drivers/staging/rt2870/2870_main_dev.c b/drivers/staging/rt2870/2870_main_dev.c
index 04c764d95d7..9d59e3167fe 100644
--- a/drivers/staging/rt2870/2870_main_dev.c
+++ b/drivers/staging/rt2870/2870_main_dev.c
@@ -265,7 +265,7 @@ INT MlmeThread(
          */
         DBGPRINT(RT_DEBUG_TRACE,( "<---%s\n",__func__));
 
-        pObj->MLMEThr_pid = THREAD_PID_INIT_VALUE;
+        pObj->MLMEThr_task = NULL;
 
         complete_and_exit (&pAd->mlmeComplete, 0);
         return 0;
@@ -373,7 +373,7 @@ INT RTUSBCmdThread(
          */
         DBGPRINT(RT_DEBUG_TRACE,( "<---RTUSBCmdThread\n"));
 
-        pObj->RTUSBCmdThr_pid = THREAD_PID_INIT_VALUE;
+        pObj->RTUSBCmdThr_task = NULL;
 
         complete_and_exit (&pAd->CmdQComplete, 0);
         return 0;
@@ -467,7 +467,7 @@ INT TimerQThread(
          */
         DBGPRINT(RT_DEBUG_TRACE,( "<---%s\n",__func__));
 
-        pObj->TimerQThr_pid = THREAD_PID_INIT_VALUE;
+        pObj->TimerQThr_task = NULL;
 
         complete_and_exit(&pAd->TimerQComplete, 0);
         return 0;
@@ -944,69 +944,46 @@ VOID RT28xxThreadTerminate(
         RTUSBCancelPendingIRPs(pAd);
 
         // Terminate Threads
-        CHECK_PID_LEGALITY(pObj->TimerQThr_pid)
+        BUG_ON(pObj->TimerQThr_task == NULL);
+        CHECK_PID_LEGALITY(task_pid(pObj->TimerQThr_task))
         {
                 POS_COOKIE pObj = (POS_COOKIE)pAd->OS_Cookie;
 
-                printk("Terminate the TimerQThr_pid=%d!\n", GET_PID_NUMBER(pObj->TimerQThr_pid));
+                printk(KERN_DEBUG "Terminate the TimerQThr pid=%d!\n",
+                        pid_nr(task_pid(pObj->TimerQThr_task)));
                 mb();
                 pAd->TimerFunc_kill = 1;
                 mb();
-                ret = KILL_THREAD_PID(pObj->TimerQThr_pid, SIGTERM, 1);
-                if (ret)
-                {
-                        printk(KERN_WARNING "%s: unable to stop TimerQThread, pid=%d, ret=%d!\n",
-                                        pAd->net_dev->name, GET_PID_NUMBER(pObj->TimerQThr_pid), ret);
-                }
-                else
-                {
-                        wait_for_completion(&pAd->TimerQComplete);
-                        pObj->TimerQThr_pid = THREAD_PID_INIT_VALUE;
-                }
+                kthread_stop(pObj->TimerQThr_task);
+                pObj->TimerQThr_task = NULL;
         }
 
-        CHECK_PID_LEGALITY(pObj->MLMEThr_pid)
+        BUG_ON(pObj->MLMEThr_task == NULL);
+        CHECK_PID_LEGALITY(task_pid(pObj->MLMEThr_task))
         {
-                printk("Terminate the MLMEThr_pid=%d!\n", GET_PID_NUMBER(pObj->MLMEThr_pid));
+                printk(KERN_DEBUG "Terminate the MLMEThr pid=%d!\n",
+                        pid_nr(task_pid(pObj->MLMEThr_task)));
                 mb();
                 pAd->mlme_kill = 1;
                 //RT28XX_MLME_HANDLER(pAd);
                 mb();
-                ret = KILL_THREAD_PID(pObj->MLMEThr_pid, SIGTERM, 1);
-                if (ret)
-                {
-                        printk (KERN_WARNING "%s: unable to Mlme thread, pid=%d, ret=%d!\n",
-                                        pAd->net_dev->name, GET_PID_NUMBER(pObj->MLMEThr_pid), ret);
-                }
-                else
-                {
-                        //wait_for_completion (&pAd->notify);
-                        wait_for_completion (&pAd->mlmeComplete);
-                        pObj->MLMEThr_pid = THREAD_PID_INIT_VALUE;
-                }
+                kthread_stop(pObj->MLMEThr_task);
+                pObj->MLMEThr_task = NULL;
         }
 
-        CHECK_PID_LEGALITY(pObj->RTUSBCmdThr_pid)
+        BUG_ON(pObj->RTUSBCmdThr_task == NULL);
+        CHECK_PID_LEGALITY(task_pid(pObj->RTUSBCmdThr_task))
         {
-                printk("Terminate the RTUSBCmdThr_pid=%d!\n", GET_PID_NUMBER(pObj->RTUSBCmdThr_pid));
+                printk(KERN_DEBUG "Terminate the RTUSBCmdThr pid=%d!\n",
+                        pid_nr(task_pid(pObj->RTUSBCmdThr_task)));
                 mb();
                 NdisAcquireSpinLock(&pAd->CmdQLock);
                 pAd->CmdQ.CmdQState = RT2870_THREAD_STOPED;
                 NdisReleaseSpinLock(&pAd->CmdQLock);
                 mb();
                 //RTUSBCMDUp(pAd);
-                ret = KILL_THREAD_PID(pObj->RTUSBCmdThr_pid, SIGTERM, 1);
-                if (ret)
-                {
-                        printk(KERN_WARNING "%s: unable to RTUSBCmd thread, pid=%d, ret=%d!\n",
-                                        pAd->net_dev->name, GET_PID_NUMBER(pObj->RTUSBCmdThr_pid), ret);
-                }
-                else
-                {
-                        //wait_for_completion (&pAd->notify);
-                        wait_for_completion (&pAd->CmdQComplete);
-                        pObj->RTUSBCmdThr_pid = THREAD_PID_INIT_VALUE;
-        }
+                kthread_stop(pObj->RTUSBCmdThr_task);
+                pObj->RTUSBCmdThr_task = NULL;
         }
 
 
@@ -1067,7 +1044,7 @@ BOOLEAN RT28XXChipsetCheck(
                 if (dev_p->descriptor.idVendor == rtusb_usb_id[i].idVendor &&
                         dev_p->descriptor.idProduct == rtusb_usb_id[i].idProduct)
                 {
-                        printk("rt2870: idVendor = 0x%x, idProduct = 0x%x\n",
+                        printk(KERN_DEBUG "rt2870: idVendor = 0x%x, idProduct = 0x%x\n",
                                         dev_p->descriptor.idVendor, dev_p->descriptor.idProduct);
                         break;
                 }
diff --git a/drivers/staging/rt2870/common/2870_rtmp_init.c b/drivers/staging/rt2870/common/2870_rtmp_init.c
index 9f5143b3922..cb16d2fcf60 100644
--- a/drivers/staging/rt2870/common/2870_rtmp_init.c
+++ b/drivers/staging/rt2870/common/2870_rtmp_init.c
@@ -727,8 +727,8 @@ NDIS_STATUS AdapterBlockAllocateMemory(
 
         usb_dev = pObj->pUsb_Dev;
 
-        pObj->MLMEThr_pid               = THREAD_PID_INIT_VALUE;
-        pObj->RTUSBCmdThr_pid   = THREAD_PID_INIT_VALUE;
+        pObj->MLMEThr_task              = NULL;
+        pObj->RTUSBCmdThr_task  = NULL;
 
         *ppAd = (PVOID)vmalloc(sizeof(RTMP_ADAPTER));
 
@@ -765,7 +765,7 @@ NDIS_STATUS	 CreateThreads(
 {
         PRTMP_ADAPTER pAd = net_dev->ml_priv;
         POS_COOKIE pObj = (POS_COOKIE) pAd->OS_Cookie;
-        pid_t pid_number = -1;
+        struct task_struct *tsk;
 
         //init_MUTEX(&(pAd->usbdev_semaphore));
 
@@ -779,36 +779,39 @@ NDIS_STATUS	 CreateThreads(
         init_completion (&pAd->TimerQComplete);
 
         // Creat MLME Thread
-        pObj->MLMEThr_pid= THREAD_PID_INIT_VALUE;
-        pid_number = kernel_thread(MlmeThread, pAd, CLONE_VM);
-        if (pid_number < 0)
-        {
+        pObj->MLMEThr_task = NULL;
+        tsk = kthread_run(MlmeThread, pAd, pAd->net_dev->name);
+
+        if (IS_ERR(tsk)) {
                 printk (KERN_WARNING "%s: unable to start Mlme thread\n",pAd->net_dev->name);
                 return NDIS_STATUS_FAILURE;
         }
-        pObj->MLMEThr_pid = GET_PID(pid_number);
+
+        pObj->MLMEThr_task = tsk;
         // Wait for the thread to start
         wait_for_completion(&(pAd->mlmeComplete));
 
         // Creat Command Thread
-        pObj->RTUSBCmdThr_pid= THREAD_PID_INIT_VALUE;
-        pid_number = kernel_thread(RTUSBCmdThread, pAd, CLONE_VM);
-        if (pid_number < 0)
+        pObj->RTUSBCmdThr_task = NULL;
+        tsk = kthread_run(RTUSBCmdThread, pAd, pAd->net_dev->name);
+
+        if (IS_ERR(tsk) < 0)
         {
                 printk (KERN_WARNING "%s: unable to start RTUSBCmd thread\n",pAd->net_dev->name);
                 return NDIS_STATUS_FAILURE;
         }
-        pObj->RTUSBCmdThr_pid = GET_PID(pid_number);
+
+        pObj->RTUSBCmdThr_task = tsk;
         wait_for_completion(&(pAd->CmdQComplete));
 
-        pObj->TimerQThr_pid= THREAD_PID_INIT_VALUE;
-        pid_number = kernel_thread(TimerQThread, pAd, CLONE_VM);
-        if (pid_number < 0)
+        pObj->TimerQThr_task = NULL;
+        tsk = kthread_run(TimerQThread, pAd, pAd->net_dev->name);
+        if (IS_ERR(tsk) < 0)
         {
                 printk (KERN_WARNING "%s: unable to start TimerQThread\n",pAd->net_dev->name);
                 return NDIS_STATUS_FAILURE;
         }
-        pObj->TimerQThr_pid = GET_PID(pid_number);
+        pObj->TimerQThr_task = tsk;
         // Wait for the thread to start
         wait_for_completion(&(pAd->TimerQComplete));
 
diff --git a/drivers/staging/rt2870/common/cmm_data.c b/drivers/staging/rt2870/common/cmm_data.c
index fd809abf6df..f8e0ebd7bca 100644
--- a/drivers/staging/rt2870/common/cmm_data.c
+++ b/drivers/staging/rt2870/common/cmm_data.c
@@ -709,9 +709,6 @@ BOOLEAN RTMP_FillTxBlkInfo(
         }
 
         return TRUE;
-
-FillTxBlkErr:
-        return FALSE;
 }
 
 
diff --git a/drivers/staging/rt2870/common/rtmp_init.c b/drivers/staging/rt2870/common/rtmp_init.c
index 870a00da3da..099b6a806f8 100644
--- a/drivers/staging/rt2870/common/rtmp_init.c
+++ b/drivers/staging/rt2870/common/rtmp_init.c
@@ -3655,7 +3655,7 @@ VOID	UserCfgInit(
 #ifdef RALINK_28xx_QA
         //pAd->ate.Repeat = 0;
         pAd->ate.TxStatus = 0;
-        pAd->ate.AtePid = THREAD_PID_INIT_VALUE;
+        pAd->ate.AtePid = NULL;
 #endif // RALINK_28xx_QA //
 #endif // RALINK_ATE //
 
diff --git a/drivers/staging/rt2870/common/rtusb_io.c b/drivers/staging/rt2870/common/rtusb_io.c
index 6db443e9268..afde136a9a0 100644
--- a/drivers/staging/rt2870/common/rtusb_io.c
+++ b/drivers/staging/rt2870/common/rtusb_io.c
@@ -958,7 +958,8 @@ NDIS_STATUS	RTUSBEnqueueCmdFromNdis(
         POS_COOKIE pObj = (POS_COOKIE) pAd->OS_Cookie;
 
 
-        CHECK_PID_LEGALITY(pObj->RTUSBCmdThr_pid)
+        BUG_ON(pObj->RTUSBCmdThr_task == NULL);
+        CHECK_PID_LEGALITY(task_pid(pObj->RTUSBCmdThr_task))
                 return (NDIS_STATUS_RESOURCES);
 
         status = RTMPAllocateMemory((PVOID *)&cmdqelmt, sizeof(CmdQElmt));
diff --git a/drivers/staging/rt2870/rt2870.h b/drivers/staging/rt2870/rt2870.h
index b8ccc50bbda..5dd15aac9ce 100644
--- a/drivers/staging/rt2870/rt2870.h
+++ b/drivers/staging/rt2870/rt2870.h
@@ -577,14 +577,16 @@ VOID RTUSBBulkRxComplete(purbb_t pUrb, struct pt_regs *pt_regs);
 #define RTUSBMlmeUp(pAd)                \
 {                                                                   \
         POS_COOKIE pObj = (POS_COOKIE) pAd->OS_Cookie;  \
-        CHECK_PID_LEGALITY(pObj->MLMEThr_pid)               \
+        BUG_ON(pObj->MLMEThr_task == NULL);                 \
+        CHECK_PID_LEGALITY(task_pid(pObj->MLMEThr_task))                    \
         up(&(pAd->mlme_semaphore)); \
 }
 
 #define RTUSBCMDUp(pAd)                 \
 {                                                                           \
         POS_COOKIE pObj = (POS_COOKIE) pAd->OS_Cookie;  \
-        CHECK_PID_LEGALITY(pObj->RTUSBCmdThr_pid)           \
+        BUG_ON(pObj->RTUSBCmdThr_task == NULL);     \
+        CHECK_PID_LEGALITY(task_pid(pObj->RTUSBCmdThr_task))        \
             up(&(pAd->RTUSBCmd_semaphore)); \
 }
 
diff --git a/drivers/staging/rt2870/rt_linux.h b/drivers/staging/rt2870/rt_linux.h
index 49ad37f0063..5a6ee6ad0e5 100644
--- a/drivers/staging/rt2870/rt_linux.h
+++ b/drivers/staging/rt2870/rt_linux.h
@@ -44,6 +44,7 @@
 #include <linux/module.h>
 #include <linux/version.h>
 #include <linux/kernel.h>
+#include <linux/kthread.h>
 
 #include <linux/spinlock.h>
 #include <linux/init.h>
@@ -165,14 +166,12 @@ typedef int (*HARD_START_XMIT_FUNC)(struct sk_buff *skb, struct net_device *net_
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,27)
 typedef struct pid *    THREAD_PID;
-#define THREAD_PID_INIT_VALUE   NULL
 #define GET_PID(_v)     find_get_pid(_v)
 #define GET_PID_NUMBER(_v)      pid_nr(_v)
 #define CHECK_PID_LEGALITY(_pid)        if (pid_nr(_pid) >= 0)
 #define KILL_THREAD_PID(_A, _B, _C)     kill_pid(_A, _B, _C)
 #else
 typedef pid_t   THREAD_PID;
-#define THREAD_PID_INIT_VALUE   -1
 #define GET_PID(_v)     _v
 #define GET_PID_NUMBER(_v)      _v
 #define CHECK_PID_LEGALITY(_pid)        if (_pid >= 0)
@@ -188,11 +187,11 @@ struct os_lock  {
 struct os_cookie {
 
 #ifdef RT2870
-        struct usb_device               *pUsb_Dev;
+        struct usb_device       *pUsb_Dev;
 
-        THREAD_PID                              MLMEThr_pid;
-        THREAD_PID                              RTUSBCmdThr_pid;
-        THREAD_PID                              TimerQThr_pid;
+        struct task_struct      *MLMEThr_task;
+        struct task_struct      *RTUSBCmdThr_task;
+        struct task_struct      *TimerQThr_task;
 #endif // RT2870 //
 
         struct tasklet_struct   rx_done_task;