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netpoll: move setting of NETPOLL_RX_DROP into netpoll_poll_dev

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Today netpoll depends on setting NETPOLL_RX_DROP before networking
drivers receive packets in interrupt context so that the packets can
be dropped.  Move this setting into netpoll_poll_dev from
poll_one_napi so that if ndo_poll_controller happens to receive
packets we will drop the packets on the floor instead of letting the
packets bounce through the networking stack and potentially cause problems.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric W. Biederman 2014-03-14 20:44:37 -07:00 committed by David S. Miller
parent e86e180b82
commit b249b51b98
1 changed files with 8 additions and 8 deletions
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16
net/core/netpoll.c
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@ -144,8 +144,7 @@ static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,
* network adapter, forcing superfluous retries and possibly timeouts.
* Thus, we set our budget to greater than 1.
*/
static int poll_one_napi(struct netpoll_info *npinfo,
struct napi_struct *napi, int budget)
static int poll_one_napi(struct napi_struct *napi, int budget)
{
int work;
@ -156,16 +155,12 @@ static int poll_one_napi(struct netpoll_info *npinfo,
if (!test_bit(NAPI_STATE_SCHED, &napi->state))
return budget;
npinfo->rx_flags |= NETPOLL_RX_DROP;
atomic_inc(&trapped);
set_bit(NAPI_STATE_NPSVC, &napi->state);
work = napi->poll(napi, budget);
trace_napi_poll(napi);
clear_bit(NAPI_STATE_NPSVC, &napi->state);
atomic_dec(&trapped);
npinfo->rx_flags &= ~NETPOLL_RX_DROP;
return budget - work;
}
@ -178,8 +173,7 @@ static void poll_napi(struct net_device *dev)
list_for_each_entry(napi, &dev->napi_list, dev_list) {
if (napi->poll_owner != smp_processor_id() &&
spin_trylock(&napi->poll_lock)) {
budget = poll_one_napi(rcu_dereference_bh(dev->npinfo),
napi, budget);
budget = poll_one_napi(napi, budget);
spin_unlock(&napi->poll_lock);
if (!budget)
@ -215,6 +209,9 @@ static void netpoll_poll_dev(struct net_device *dev)
return;
}
ni->rx_flags |= NETPOLL_RX_DROP;
atomic_inc(&trapped);
ops = dev->netdev_ops;
if (!ops->ndo_poll_controller) {
up(&ni->dev_lock);
@ -226,6 +223,9 @@ static void netpoll_poll_dev(struct net_device *dev)
poll_napi(dev);
atomic_dec(&trapped);
ni->rx_flags &= ~NETPOLL_RX_DROP;
up(&ni->dev_lock);
if (dev->flags & IFF_SLAVE) {