Re: [PATCH] Replaces two GOTO statements with one IF_ELSE statementin /fs/open.c

From: Andrew Morton
Date: Mon Jun 20 2005 - 16:10:58 EST


Christoph Lameter <christoph@xxxxxxxxxxx> wrote:
>
> On Mon, 20 Jun 2005, Jeff Garzik wrote:
>
> > If you don't like goto, don't read kernel code!
>
> But his patch also cleans up a code quit a bit.

Yes, it is cleaner that way.

The old trick to make the error-handling code out-of-line shouldn't be
needed nowadays - IS_ERR uses unlikely(), which is supposed to handle that
stuff.

We can go a bit further and remove local variable `error'.

Code size is the same before and after, and the assembly very similar.

diff -puN fs/open.c~sys_open-cleanup fs/open.c
--- 25/fs/open.c~sys_open-cleanup Mon Jun 20 13:31:54 2005
+++ 25-akpm/fs/open.c Mon Jun 20 13:33:37 2005
@@ -934,7 +934,7 @@ EXPORT_SYMBOL(fd_install);
asmlinkage long sys_open(const char __user * filename, int flags, int mode)
{
char * tmp;
- int fd, error;
+ int fd;

if (force_o_largefile())
flags |= O_LARGEFILE;
@@ -945,20 +945,16 @@ asmlinkage long sys_open(const char __us
fd = get_unused_fd();
if (fd >= 0) {
struct file *f = filp_open(tmp, flags, mode);
- error = PTR_ERR(f);
- if (IS_ERR(f))
- goto out_error;
- fd_install(fd, f);
+ if (IS_ERR(f)) {
+ put_unused_fd(fd);
+ fd = PTR_ERR(f);
+ } else {
+ fd_install(fd, f);
+ }
}
-out:
putname(tmp);
}
return fd;
-
-out_error:
- put_unused_fd(fd);
- fd = error;
- goto out;
}
EXPORT_SYMBOL_GPL(sys_open);

_

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/