staging: rtl8192e: Drop useless initialisation

PATCH In review Bhaktipriya Shridhar 2 participants 3 messages Feb 18, 2016 – Feb 23, 2016 Staging

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Julia Lawall

2016-02-23 20:20 UTC #1 lore raw

Quoted 4 lines · Bhaktipriya Shridhar

Removed initialisation of a varible if it is immediately reassigned.
Changes were made using Coccinelle.

Quoted 10 lines

@@
type T;
constant C;
expression e;
identifier i;
@@
T i
- = C
;
i = e;

This could be made a little safer (although less efficient) as follows:

@bad@
identifier i;
position p;
@@

i =@p <+...i...+>;

@@
type T;
constant C;
expression e;
identifier i;
position p != bad.p;
@@
T i
- = C
;
i =@p e;

The first rule (bad) detects any assignment that updates a variable in terms of its current value. If it finds such an assignment, then it records the position of that assignment. The next rule only transforms cases that do not satisfy the position recorded by bad.

You can also just check this issue by hand.

julia

Quoted 144 lines

Signed-off-by Bhaktipriya Shridhar <[email protected]>

---
 drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c | 8 ++++----
 drivers/staging/rtl8192e/rtl8192e/rtl_dm.c     | 2 +-
 drivers/staging/rtl8192e/rtl819x_BAProc.c      | 6 +++---
 drivers/staging/rtl8192e/rtllib_rx.c           | 2 +-
 drivers/staging/rtl8192e/rtllib_softmac.c      | 2 +-
 drivers/staging/rtl8192e/rtllib_softmac_wx.c   | 2 +-
 6 files changed, 11 insertions(+), 11 deletions(-)

drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c +4 -4

index e9c4f97..ba64a4f 100644
@@ -680,7 +680,7 @@ static void _rtl92e_hwconfig(struct net_device *dev)
 
 	rtl92e_writeb(dev, BW_OPMODE, regBwOpMode);
 	{
-		u32 ratr_value = 0;
+		u32 ratr_value;
 
 		ratr_value = regRATR;
 		if (priv->rf_type == RF_1T2R)

@@ -1000,7 +1000,7 @@ void rtl92e_link_change(struct net_device *dev)
 	_rtl92e_update_msr(dev);
 
 	if (ieee->iw_mode == IW_MODE_INFRA || ieee->iw_mode == IW_MODE_ADHOC) {
-		u32 reg = 0;
+		u32 reg;
 
 		reg = rtl92e_readl(dev, RCR);
 		if (priv->rtllib->state == RTLLIB_LINKED) {

@@ -1186,7 +1186,7 @@ void  rtl92e_fill_tx_desc(struct net_device *dev, struct tx_desc *pdesc,
 	struct r8192_priv *priv = rtllib_priv(dev);
 	dma_addr_t mapping = pci_map_single(priv->pdev, skb->data, skb->len,
 			 PCI_DMA_TODEVICE);
-	struct tx_fwinfo_8190pci *pTxFwInfo = NULL;
+	struct tx_fwinfo_8190pci *pTxFwInfo;
 
 	pTxFwInfo = (struct tx_fwinfo_8190pci *)skb->data;
 	memset(pTxFwInfo, 0, sizeof(struct tx_fwinfo_8190pci));

@@ -2235,7 +2235,7 @@ void rtl92e_disable_irq(struct net_device *dev)
 
 void rtl92e_clear_irq(struct net_device *dev)
 {
-	u32 tmp = 0;
+	u32 tmp;
 
 	tmp = rtl92e_readl(dev, ISR);
 	rtl92e_writel(dev, ISR, tmp);

drivers/staging/rtl8192e/rtl8192e/rtl_dm.c +1 -1

index ef03242..b6b714d 100644
@@ -1875,7 +1875,7 @@ void rtl92e_dm_rf_pathcheck_wq(void *data)
 				  struct r8192_priv,
 				  rfpath_check_wq);
 	struct net_device *dev = priv->rtllib->dev;
-	u8 rfpath = 0, i;
+	u8 rfpath, i;
 
 	rfpath = rtl92e_readb(dev, 0xc04);

drivers/staging/rtl8192e/rtl819x_BAProc.c +3 -3

index c04a020..c7fd1b1 100644
@@ -189,7 +189,7 @@ static struct sk_buff *rtllib_DELBA(struct rtllib_device *ieee, u8 *dst,
 static void rtllib_send_ADDBAReq(struct rtllib_device *ieee, u8 *dst,
 				 struct ba_record *pBA)
 {
-	struct sk_buff *skb = NULL;
+	struct sk_buff *skb;
 
 	skb = rtllib_ADDBA(ieee, dst, pBA, 0, ACT_ADDBAREQ);

@@ -204,7 +204,7 @@ static void rtllib_send_ADDBAReq(struct rtllib_device *ieee, u8 *dst,
 static void rtllib_send_ADDBARsp(struct rtllib_device *ieee, u8 *dst,
 				 struct ba_record *pBA, u16 StatusCode)
 {
-	struct sk_buff *skb = NULL;
+	struct sk_buff *skb;
 
 	skb = rtllib_ADDBA(ieee, dst, pBA, StatusCode, ACT_ADDBARSP);
 	if (skb)

@@ -217,7 +217,7 @@ static void rtllib_send_DELBA(struct rtllib_device *ieee, u8 *dst,
 			      struct ba_record *pBA, enum tr_select TxRxSelect,
 			      u16 ReasonCode)
 {
-	struct sk_buff *skb = NULL;
+	struct sk_buff *skb;
 
 	skb = rtllib_DELBA(ieee, dst, pBA, TxRxSelect, ReasonCode);
 	if (skb)

drivers/staging/rtl8192e/rtllib_rx.c +1 -1

index 37343ec..af64bd3 100644
@@ -905,7 +905,7 @@ static size_t rtllib_rx_get_hdrlen(struct rtllib_device *ieee,
 {
 	struct rtllib_hdr_4addr *hdr = (struct rtllib_hdr_4addr *)skb->data;
 	u16 fc = le16_to_cpu(hdr->frame_ctl);
-	size_t hdrlen = 0;
+	size_t hdrlen;
 
 	hdrlen = rtllib_get_hdrlen(fc);
 	if (HTCCheck(ieee, skb->data)) {

drivers/staging/rtl8192e/rtllib_softmac.c +1 -1

index 19c3bff..25b5b5e 100644
@@ -776,7 +776,7 @@ inline struct sk_buff *rtllib_authentication_req(struct rtllib_network *beacon,
 {
 	struct sk_buff *skb;
 	struct rtllib_authentication *auth;
-	int  len = 0;
+	int  len;
 
 	len = sizeof(struct rtllib_authentication) + challengelen +
 		     ieee->tx_headroom + 4;

drivers/staging/rtl8192e/rtllib_softmac_wx.c +1 -2

index 86f52ac..01a75bd 100644
@@ -243,7 +243,7 @@ int rtllib_wx_get_rate(struct rtllib_device *ieee,
 			     struct iw_request_info *info,
 			     union iwreq_data *wrqu, char *extra)
 {
-	u32 tmp_rate = 0;
+	u32 tmp_rate;
 
 	tmp_rate = TxCountToDataRate(ieee,
 				     ieee->softmac_stats.CurrentShowTxate);
--

2.1.4

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Bhaktipriya Shridhar

author

2016-02-23 20:58 UTC #2 lore raw

Hello Julia,

Thank you for your reply. I'm new to the usage of positions and your explanation really helped.
Will surely keep that in mind for next time.

I'm also sending in 2 new patches which incorporate these changes.

Thanks,
Bhaktipriya

Quoted 192 lines · Julia Lawall