[PATCH net-next 4/4] net: fib: avoid calling fib_flush for each device when doing batch close and unregister
From: Salam Noureddine <hidden>
Date: 2016-02-01 22:33:32
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
Call fib_flush at the end when closing or unregistering multiple devices. This can save walking the fib many times and greatly reduce rtnl_lock hold time when unregistering many devices with a fib having hundreds of thousands of routes. Signed-off-by: Salam Noureddine <redacted> --- include/net/netns/ipv4.h | 1 + net/ipv4/fib_frontend.c | 16 ++++++++++++++-- 2 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index d75be32..d59a078 100644
--- a/include/net/netns/ipv4.h
+++ b/include/net/netns/ipv4.h@@ -111,5 +111,6 @@ struct netns_ipv4 { #endif #endif atomic_t rt_genid; + bool needs_fib_flush; }; #endif
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 4734475..808426e 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c@@ -1161,11 +1161,22 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo unsigned int flags; if (event == NETDEV_UNREGISTER) { - fib_disable_ip(dev, event, true); + if (fib_sync_down_dev(dev, event, true)) + net->ipv4.needs_fib_flush = true; rt_flush_dev(dev); return NOTIFY_DONE; } + if (event == NETDEV_UNREGISTER_BATCH || event == NETDEV_DOWN_BATCH) { + if (net->ipv4.needs_fib_flush) { + fib_flush(net); + net->ipv4.needs_fib_flush = false; + } + rt_cache_flush(net); + arp_ifdown_all(); + return NOTIFY_DONE; + } + in_dev = __in_dev_get_rtnl(dev); if (!in_dev) return NOTIFY_DONE;
@@ -1182,7 +1193,8 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo rt_cache_flush(net); break; case NETDEV_DOWN: - fib_disable_ip(dev, event, false); + if (fib_sync_down_dev(dev, event, false)) + net->ipv4.needs_fib_flush = true; break; case NETDEV_CHANGE: flags = dev_get_flags(dev);
--
1.8.1.4