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bluetooth: btwilink: remove unnecessary static in bt_ti_probe()

PATCH In review Gustavo A. R. Silva 2 participants 3 messages Jul 19, 2017 – Jul 20, 2017 Bluetooth drivers

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Gustavo A. R. Silva

author
#0 lore raw

PATCH 1/1 bluetooth: btwilink: remove unnecessary static in bt_ti_probe()

Remove unnecessary static on local variable hst. Such variable is initialized before being used, on every execution path throughout the function. The static has no benefit and, removing it reduces the object file size.

This issue was detected using Coccinelle and the
following semantic patch:

@bad exists@
position p;
identifier x;
type T;
@@

static T x@p;
...
x = <+...x...+>

@@
identifier x;
expression e;
type T;
position p != bad.p;
@@

-static
T x@p;
... when != x
when strict
?x = e;

In the following log you can see the difference in the object file size. This log is the output of the size command, before and after the code change:

before:

   text    data     bss     dec     hex filename
   4029    2528     128    6685    1a1d drivers/bluetooth/btwilink.o

after:
text data bss dec hex filename
4007 2472 64 6543 198f drivers/bluetooth/btwilink.o

Signed-off-by Gustavo A. R. Silva <[email protected]>
---
 drivers/bluetooth/btwilink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/bluetooth/btwilink.c +1 -1
index 85a3978..0cdb896 100644
@@ -276,7 +276,7 @@ static int ti_st_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 
 static int bt_ti_probe(struct platform_device *pdev)
 {
-	static struct ti_st *hst;
+	struct ti_st *hst;
 	struct hci_dev *hdev;
 	int err;
Signature · 1 line
2.5.0
maintainer
#1 lore raw

Hi Gustavo,

Quoted 40 lines

Remove unnecessary static on local variable hst. Such variable is initialized before being used, on every execution path throughout the function. The static has no benefit and, removing it reduces the object file size.

This issue was detected using Coccinelle and the
following semantic patch:

@bad exists@
position p;
identifier x;
type T;
@@

static T x@p;
...
x = <+...x...+>

@@
identifier x;
expression e;
type T;
position p != bad.p;
@@

-static
T x@p;
... when != x
when strict
?x = e;

In the following log you can see the difference in the object file size. This log is the output of the size command, before and after the code change:

before:

  text    data     bss     dec     hex filename
  4029    2528     128    6685    1a1d drivers/bluetooth/btwilink.o
Quoted 8 lines

after:
text data bss dec hex filename
4007 2472 64 6543 198f drivers/bluetooth/btwilink.o

Signed-off-by Gustavo A. R. Silva <[email protected]>

---
drivers/bluetooth/btwilink.c | 2 +-

1 file changed, 1 insertion(+), 1 deletion(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel

author
#2 lore raw

Hi Marcel,

Quoted 46 lines · Marcel Holtmann

Hi Gustavo,

Quoted 44 lines

Remove unnecessary static on local variable hst. Such variable is initialized before being used, on every execution path throughout the function. The static has no benefit and, removing it reduces the object file size.

This issue was detected using Coccinelle and the
following semantic patch:

@bad exists@
position p;
identifier x;
type T;
@@

static T x@p;
...
x = <+...x...+>

@@
identifier x;
expression e;
type T;
position p != bad.p;
@@

-static
T x@p;
... when != x
when strict
?x = e;

In the following log you can see the difference in the object file size. This log is the output of the size command, before and after the code change:

before:

  text    data     bss     dec     hex filename
  4029    2528     128    6685    1a1d drivers/bluetooth/btwilink.o

after:
text data bss dec hex filename
4007 2472 64 6543 198f drivers/bluetooth/btwilink.o

Quoted 7 lines
Quoted 4 lines
Signed-off-by Gustavo A. R. Silva <[email protected]>

---
drivers/bluetooth/btwilink.c | 2 +-

1 file changed, 1 insertion(+), 1 deletion(-)

patch has been applied to bluetooth-next tree.

Great, thanks!

Signature · 1 line
Gustavo A. R. Silva