net: use napi_id_valid helper

In commit 6597e8d35851 ("netdev-genl: Elide napi_id when not present"),
napi_id_valid function was added. Use the helper to refactor open-coded
checks in the source.

Suggested-by: Paolo Abeni <[e-mail]>
Signed-off-by: Stefano Jordhani <[e-mail]>
Reviewed-by: Joe Damato <[e-mail]>
Reviewed-by: Jens Axboe <[e-mail]> # for iouring
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

fs/eventpoll.c

···
 	if (!budget)
 		budget = BUSY_POLL_BUDGET;
 
-	if (napi_id >= MIN_NAPI_ID && ep_busy_loop_on(ep)) {
+	if (napi_id_valid(napi_id) && ep_busy_loop_on(ep)) {
 		napi_busy_loop(napi_id, nonblock ? NULL : ep_busy_loop_end,
 			       ep, prefer_busy_poll, budget);
 		if (ep_events_available(ep))
···
 	 *	or
 	 * Nothing to do if we already have this ID
 	 */
-	if (napi_id < MIN_NAPI_ID || napi_id == ep->napi_id)
+	if (!napi_id_valid(napi_id) || napi_id == ep->napi_id)
 		return;
 
 	/* record NAPI ID for use in next busy poll */
···
 {
 	unsigned int napi_id = READ_ONCE(ep->napi_id);
 
-	if (napi_id >= MIN_NAPI_ID && READ_ONCE(ep->prefer_busy_poll))
+	if (napi_id_valid(napi_id) && READ_ONCE(ep->prefer_busy_poll))
 		napi_suspend_irqs(napi_id);
 }
 
···
 {
 	unsigned int napi_id = READ_ONCE(ep->napi_id);
 
-	if (napi_id >= MIN_NAPI_ID && READ_ONCE(ep->prefer_busy_poll))
+	if (napi_id_valid(napi_id) && READ_ONCE(ep->prefer_busy_poll))
 		napi_resume_irqs(napi_id);
 }
 

include/net/busy_poll.h

···
 #ifdef CONFIG_NET_RX_BUSY_POLL
 	unsigned int napi_id = READ_ONCE(sk->sk_napi_id);
 
-	if (napi_id >= MIN_NAPI_ID)
+	if (napi_id_valid(napi_id))
 		napi_busy_loop(napi_id, nonblock ? NULL : sk_busy_loop_end, sk,
 			       READ_ONCE(sk->sk_prefer_busy_poll),
 			       READ_ONCE(sk->sk_busy_poll_budget) ?: BUSY_POLL_BUDGET);
···
 	/* If the skb was already marked with a valid NAPI ID, avoid overwriting
 	 * it.
 	 */
-	if (skb->napi_id < MIN_NAPI_ID)
+	if (!napi_id_valid(skb->napi_id))
 		skb->napi_id = napi->napi_id;
 #endif
 }

io_uring/napi.c

···
 	struct io_napi_entry *e;
 
 	/* Non-NAPI IDs can be rejected. */
-	if (napi_id < MIN_NAPI_ID)
+	if (!napi_id_valid(napi_id))
 		return -EINVAL;
 
 	hash_list = &ctx->napi_ht[hash_min(napi_id, HASH_BITS(ctx->napi_ht))];
···
 	struct io_napi_entry *e;
 
 	/* Non-NAPI IDs can be rejected. */
-	if (napi_id < MIN_NAPI_ID)
+	if (!napi_id_valid(napi_id))
 		return -EINVAL;
 
 	hash_list = &ctx->napi_ht[hash_min(napi_id, HASH_BITS(ctx->napi_ht))];

net/core/dev.c

···
 
 	WARN_ON_ONCE(!rcu_read_lock_held());
 
-	if (napi_id < MIN_NAPI_ID)
+	if (!napi_id_valid(napi_id))
 		return NULL;
 
 	napi = napi_by_id(napi_id);
···
 
 	/* 0..NR_CPUS range is reserved for sender_cpu use */
 	do {
-		if (unlikely(++napi_gen_id < MIN_NAPI_ID))
+		if (unlikely(!napi_id_valid(++napi_gen_id)))
 			napi_gen_id = MIN_NAPI_ID;
 	} while (napi_by_id(napi_gen_id));
 
···
 
 	higher = &dev->napi_list;
 	list_for_each_entry(pos, &dev->napi_list, dev_list) {
-		if (pos->napi_id >= MIN_NAPI_ID)
+		if (napi_id_valid(pos->napi_id))
 			pos_id = pos->napi_id;
 		else if (pos->config)
 			pos_id = pos->config->napi_id;

net/core/netdev-genl.c

···
 
 	prev_id = UINT_MAX;
 	list_for_each_entry(napi, &netdev->napi_list, dev_list) {
-		if (napi->napi_id < MIN_NAPI_ID)
+		if (!napi_id_valid(napi->napi_id))
 			continue;
 
 		/* Dump continuation below depends on the list being sorted */

net/core/page_pool_user.c

···
 		goto err_cancel;
 
 	napi_id = pool->p.napi ? READ_ONCE(pool->p.napi->napi_id) : 0;
-	if (napi_id >= MIN_NAPI_ID &&
+	if (napi_id_valid(napi_id) &&
 	    nla_put_uint(rsp, NETDEV_A_PAGE_POOL_NAPI_ID, napi_id))
 		goto err_cancel;
 

net/core/sock.c

···
 		v.val = READ_ONCE(sk->sk_napi_id);
 
 		/* aggregate non-NAPI IDs down to 0 */
-		if (v.val < MIN_NAPI_ID)
+		if (!napi_id_valid(v.val))
 			v.val = 0;
 
 		break;

net/xdp/xsk.c

···
 #ifdef CONFIG_NET_RX_BUSY_POLL
 	/* Prefer busy-polling, skip the wakeup. */
 	return READ_ONCE(sk->sk_prefer_busy_poll) && READ_ONCE(sk->sk_ll_usec) &&
-		READ_ONCE(sk->sk_napi_id) >= MIN_NAPI_ID;
+		napi_id_valid(READ_ONCE(sk->sk_napi_id));
 #else
 	return false;
 #endif