diff options
author | Amerigo Wang <amwang@redhat.com> | 2012-08-10 01:24:38 +0000 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2012-08-14 14:33:30 -0700 |
commit | 38e6bc185d9544dfad1774b3f8902a0b061aea25 (patch) | |
tree | 5dc41a28f9dc48095c998dfc0dcf8b970db6e1b5 /net/core/netpoll.c | |
parent | 47be03a28cc6c80e3aa2b3e8ed6d960ff0c5c0af (diff) | |
download | op-kernel-dev-38e6bc185d9544dfad1774b3f8902a0b061aea25.zip op-kernel-dev-38e6bc185d9544dfad1774b3f8902a0b061aea25.tar.gz |
netpoll: make __netpoll_cleanup non-block
Like the previous patch, slave_disable_netpoll() and __netpoll_cleanup()
may be called with read_lock() held too, so we should make them
non-block, by moving the cleanup and kfree() to call_rcu_bh() callbacks.
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/netpoll.c')
-rw-r--r-- | net/core/netpoll.c | 42 |
1 files changed, 32 insertions, 10 deletions
diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 37cc854..dc17f1d 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -878,6 +878,24 @@ static int __init netpoll_init(void) } core_initcall(netpoll_init); +static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head) +{ + struct netpoll_info *npinfo = + container_of(rcu_head, struct netpoll_info, rcu); + + skb_queue_purge(&npinfo->arp_tx); + skb_queue_purge(&npinfo->txq); + + /* we can't call cancel_delayed_work_sync here, as we are in softirq */ + cancel_delayed_work(&npinfo->tx_work); + + /* clean after last, unfinished work */ + __skb_queue_purge(&npinfo->txq); + /* now cancel it again */ + cancel_delayed_work(&npinfo->tx_work); + kfree(npinfo); +} + void __netpoll_cleanup(struct netpoll *np) { struct netpoll_info *npinfo; @@ -903,20 +921,24 @@ void __netpoll_cleanup(struct netpoll *np) ops->ndo_netpoll_cleanup(np->dev); RCU_INIT_POINTER(np->dev->npinfo, NULL); + call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info); + } +} +EXPORT_SYMBOL_GPL(__netpoll_cleanup); - /* avoid racing with NAPI reading npinfo */ - synchronize_rcu_bh(); +static void rcu_cleanup_netpoll(struct rcu_head *rcu_head) +{ + struct netpoll *np = container_of(rcu_head, struct netpoll, rcu); - skb_queue_purge(&npinfo->arp_tx); - skb_queue_purge(&npinfo->txq); - cancel_delayed_work_sync(&npinfo->tx_work); + __netpoll_cleanup(np); + kfree(np); +} - /* clean after last, unfinished work */ - __skb_queue_purge(&npinfo->txq); - kfree(npinfo); - } +void __netpoll_free_rcu(struct netpoll *np) +{ + call_rcu_bh(&np->rcu, rcu_cleanup_netpoll); } -EXPORT_SYMBOL_GPL(__netpoll_cleanup); +EXPORT_SYMBOL_GPL(__netpoll_free_rcu); void netpoll_cleanup(struct netpoll *np) { |