Re: [PATCH] no need to check for NULL before calling kfree() - fs/ext2/

Isn't it expensive of CPU time to call kfree() even though the
pointer may have already been freed? I suggest that the check
for a NULL before the call is much less expensive than calling
kfree() and doing the check there. The resulting "double check"
is cheap, compared to the call.

On Fri, 25 Mar 2005, Jesper Juhl wrote:

(please keep me on CC)


kfree() handles NULL fine, to check is redundant.

Signed-off-by: Jesper Juhl <[email protected]>

--- linux-2.6.12-rc1-mm3-orig/fs/ext2/acl.c	2005-03-02 08:38:18.000000000 +0100
+++ linux-2.6.12-rc1-mm3/fs/ext2/acl.c	2005-03-25 22:41:07.000000000 +0100
@@ -194,8 +194,7 @@ ext2_get_acl(struct inode *inode, int ty
		acl = NULL;
	else
		acl = ERR_PTR(retval);
-	if (value)
-		kfree(value);
+	kfree(value);

	if (!IS_ERR(acl)) {
		switch(type) {
@@ -262,8 +261,7 @@ ext2_set_acl(struct inode *inode, int ty

	error = ext2_xattr_set(inode, name_index, "", value, size, 0);

-	if (value)
-		kfree(value);
+	kfree(value);
	if (!error) {
		switch(type) {
			case ACL_TYPE_ACCESS:


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Cheers,
Dick Johnson
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---

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