[PATCH] Removal of kernel_thread() API in RT2870

From: Peter Teoh
Date: Fri Mar 20 2009 - 14:20:38 EST


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.

The patch (to be applied against linus git tree
v2.6.29-rc8-241-g65c2449) attached compiled and loaded successfully -
but not with the hardware, as I don't have it.

Thanks.

PS: attached passed checkpatch.pl. Thanks.
Signed-off-by: Peter Teoh <htmldeveloper@xxxxxxxxx>

diff --git a/drivers/staging/rt2870/2870_main_dev.c b/drivers/staging/rt2870/2870_main_dev.c
index 04c764d..9d59e31 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 9f5143b..cb16d2f 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 fd809ab..f8e0ebd 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 870a00d..099b6a8 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 6db443e..afde136 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 30af4b5..80f2482 100644
--- a/drivers/staging/rt2870/rt2870.h
+++ b/drivers/staging/rt2870/rt2870.h
@@ -576,14 +576,16 @@ 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 859f9ce..7b392b8 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>
@@ -166,14 +167,12 @@ 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)
@@ -189,11 +188,11 @@ 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;