net: busy-poll: remove need_resched() from sk_can_busy_loop()

Now sk_busy_loop() can schedule by itself, we can remove
need_resched() check from sk_can_busy_loop()

Also add a const to its struct sock parameter.

Signed-off-by: Eric Dumazet <[email protected]>
Cc: Willem de Bruijn <[email protected]>
Cc: Adam Belay <[email protected]>
Cc: Tariq Toukan <[email protected]>
Cc: Yuval Mintz <[email protected]>
Cc: Ariel Elior <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: edumazet

include/net/busy_poll.h

@@ -58,10 +58,9 @@ static inline unsigned long busy_loop_end_time(void)
 	return busy_loop_us_clock() + ACCESS_ONCE(sysctl_net_busy_poll);
 }
 
-static inline bool sk_can_busy_loop(struct sock *sk)
+static inline bool sk_can_busy_loop(const struct sock *sk)
 {
-	return sk->sk_ll_usec && sk->sk_napi_id &&
-	       !need_resched() && !signal_pending(current);
+	return sk->sk_ll_usec && sk->sk_napi_id && !signal_pending(current);
 }