[PATCH v3 5/9] drivers/staging/gdm72xx/gdm_sdio.c: Remove useless kfree

Peter Senna Tschudin peter.senna at gmail.com
Fri Sep 14 15:13:50 UTC 2012


From: Peter Senna Tschudin <peter.senna at gmail.com>

Remove useless kfree() and clean up code related to the removal.

The semantic patch that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
position p1,p2;
expression x;
@@

if (x at p1 == NULL) { ... kfree at p2(x); ... return ...; }

@unchanged exists@
position r.p1,r.p2;
expression e <= r.x,x,e1;
iterator I;
statement S;
@@

if (x at p1 == NULL) { ... when != I(x,...) S
                        when != e = e1
                        when != e += e1
                        when != e -= e1
                        when != ++e
                        when != --e
                        when != e++
                        when != e--
                        when != &e
   kfree at p2(x); ... return ...; }

@ok depends on unchanged exists@
position any r.p1;
position r.p2;
expression x;
@@

... when != true x at p1 == NULL
kfree at p2(x);

@depends on !ok && unchanged@
position r.p2;
expression x;
@@

*kfree at p2(x);
// </smpl>

Signed-off-by: Peter Senna Tschudin <peter.senna at gmail.com>

---
 drivers/staging/gdm72xx/gdm_sdio.c |   13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/gdm72xx/gdm_sdio.c b/drivers/staging/gdm72xx/gdm_sdio.c
index f824290..2e1a964 100644
--- a/drivers/staging/gdm72xx/gdm_sdio.c
+++ b/drivers/staging/gdm72xx/gdm_sdio.c
@@ -91,20 +91,15 @@ static void free_tx_struct(struct sdio_tx *t)
 
 static struct sdio_rx *alloc_rx_struct(struct rx_cxt *rx)
 {
-	struct sdio_rx *r = NULL;
-
-	r = kmalloc(sizeof(*r), GFP_ATOMIC);
-	if (r == NULL)
-		goto out;
+	struct sdio_rx *r;
 
-	memset(r, 0, sizeof(*r));
+	r = kzalloc(sizeof(*r), GFP_ATOMIC);
+	if (!r)
+		return NULL;
 
 	r->rx_cxt = rx;
 
 	return r;
-out:
-	kfree(r);
-	return NULL;
 }
 
 static void free_rx_struct(struct sdio_rx *r)




More information about the devel mailing list