[PATCH] Simplify last lib/idr.c change

The last change to alloc_layer in lib/idr.c unnecessarily complicates
the code and depending on the definition of spin_unlock will cause worse
code to be generated than necessary.  The following patch should improve
the situation.
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

lib/idr.c

@@ -39,13 +39,11 @@ static struct idr_layer *alloc_layer(struct idr *idp)
 	struct idr_layer *p;
 
 	spin_lock(&idp->lock);
-	if (!(p = idp->id_free)) {
-		spin_unlock(&idp->lock);
-		return NULL;
-	}
+	if ((p = idp->id_free)) {
 		idp->id_free = p->ary[0];
 		idp->id_free_cnt--;
 		p->ary[0] = NULL;
+	}
 	spin_unlock(&idp->lock);
 	return(p);
 }