net: ipv4: convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <apais@linux.microsoft.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/ipv4/tcp_output.c

@@ -1038,9 +1038,9 @@ static void tcp_tsq_handler(struct sock *sk)
  * transferring tsq->head because tcp_wfree() might
  * interrupt us (non NAPI drivers)
  */
-static void tcp_tasklet_func(unsigned long data)
+static void tcp_tasklet_func(struct tasklet_struct *t)
 {
-	struct tsq_tasklet *tsq = (struct tsq_tasklet *)data;
+	struct tsq_tasklet *tsq = from_tasklet(tsq,  t, tasklet);
 	LIST_HEAD(list);
 	unsigned long flags;
 	struct list_head *q, *n;
@@ -1125,9 +1125,7 @@ void __init tcp_tasklet_init(void)
 		struct tsq_tasklet *tsq = &per_cpu(tsq_tasklet, i);
 
 		INIT_LIST_HEAD(&tsq->head);
-		tasklet_init(&tsq->tasklet,
-			     tcp_tasklet_func,
-			     (unsigned long)tsq);
+		tasklet_setup(&tsq->tasklet, tcp_tasklet_func);
 	}
 }