From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH 04/11] netpoll: alternative implementation of dropping Date: Sat, 03 Nov 2007 11:43:18 -0700 Message-ID: <20071103184338.637309632@linux-foundation.org> References: <20071103184314.216145305@linux-foundation.org> Cc: netdev@vger.kernel.org To: David Miller , Satyam Sharma Return-path: Received: from smtp2.linux-foundation.org ([207.189.120.14]:48033 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757845AbXKCXgf (ORCPT ); Sat, 3 Nov 2007 19:36:35 -0400 Content-Disposition: inline; filename=netpoll-drop-flag.patch Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Signed-off-by: Stephen Hemminger --- a/net/core/netpoll.c 2007-11-03 09:19:34.000000000 -0700 +++ b/net/core/netpoll.c 2007-11-03 09:33:31.000000000 -0700 @@ -40,7 +40,6 @@ static atomic_t trapped; #define USEC_PER_POLL 50 #define NETPOLL_RX_ENABLED 1 -#define NETPOLL_RX_DROP 2 #define MAX_SKB_SIZE \ (MAX_UDP_CHUNK + sizeof(struct udphdr) + \ @@ -128,13 +127,11 @@ static int poll_one_napi(struct netpoll_ if (!test_bit(NAPI_STATE_SCHED, &napi->state)) return budget; - npinfo->rx_flags |= NETPOLL_RX_DROP; atomic_inc(&trapped); work = napi->poll(napi, budget); atomic_dec(&trapped); - npinfo->rx_flags &= ~NETPOLL_RX_DROP; return budget - work; } @@ -475,7 +472,7 @@ int __netpoll_rx(struct sk_buff *skb) if (skb->dev->type != ARPHRD_ETHER) goto out; - /* check if netpoll clients need ARP */ + /* if receive ARP during middle of NAPI poll, then queue */ if (skb->protocol == htons(ETH_P_ARP) && atomic_read(&trapped)) { skb_queue_tail(&npi->arp_tx, skb); @@ -537,6 +534,9 @@ int __netpoll_rx(struct sk_buff *skb) return 1; out: + /* If packet received while already in poll then just + * silently drop. + */ if (atomic_read(&trapped)) { kfree_skb(skb); return 1; -- Stephen Hemminger