Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

drivers/char/mmtimer.c: Remove useless kfree

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

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

if (x@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@p2(x); ... return ...; }

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

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

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

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

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

authored by

Peter Senna Tschudin and committed by
Greg Kroah-Hartman
08b79dd1 f8885c26

+1 -2
+1 -2
drivers/char/mmtimer.c
··· 826 826 827 827 /* Allocate list of node ptrs to mmtimer_t's */ 828 828 timers = kzalloc(sizeof(struct mmtimer_node)*maxn, GFP_KERNEL); 829 - if (timers == NULL) { 829 + if (!timers) { 830 830 printk(KERN_ERR "%s: failed to allocate memory for device\n", 831 831 MMTIMER_NAME); 832 832 goto out3; ··· 848 848 return 0; 849 849 850 850 out3: 851 - kfree(timers); 852 851 misc_deregister(&mmtimer_miscdev); 853 852 out2: 854 853 free_irq(SGI_MMTIMER_VECTOR, NULL);