On 20/09/2017 2:27 AM, Eric Dumazet wrote:
When rate of netns creation/deletion is high enough,
we observe softlockups in cleanup_net() caused by huge list
of netns and way too many rcu_barrier() calls.
This patch series does some optimizations in kobject,
and add batching to tunnels so that netns dismantles are
less costly.
IPv6 addrlabels also get a per netns list, and tcp_metrics
also benefit from batch flushing.
This gives me one order of magnitude gain.
(~50 ms -> ~5 ms for one netns create/delete pair)
...
Eric Dumazet (7):
kobject: add kobject_uevent_net_broadcast()
kobject: copy env blob in one go
kobject: factorize skb setup in kobject_uevent_net_broadcast()
ipv6: addrlabel: per netns list
tcp: batch tcp_net_metrics_exit
ipv6: speedup ipv6 tunnels dismantle
ipv4: speedup ipv6 tunnels dismantle
include/net/ip_tunnels.h | 3 +-
include/net/netns/ipv6.h | 5 +++
lib/kobject_uevent.c | 94 ++++++++++++++++++++++++++----------------------
net/ipv4/ip_gre.c | 22 +++++-------
net/ipv4/ip_tunnel.c | 12 +++++--
net/ipv4/ip_vti.c | 7 ++--
net/ipv4/ipip.c | 7 ++--
net/ipv4/tcp_metrics.c | 14 +++++---
net/ipv6/addrlabel.c | 81 ++++++++++++++++-------------------------
net/ipv6/ip6_gre.c | 8 +++--
net/ipv6/ip6_tunnel.c | 20 ++++++-----
net/ipv6/ip6_vti.c | 23 +++++++-----
net/ipv6/sit.c | 9 +++--
13 files changed, 157 insertions(+), 148 deletions(-)
Hi Eric,
We see a regression introduced in this series, specifically in the
patches touching lib/kobject_uevent.c.
We tried to figure out what is wrong there, but couldn't point it out.
Bug is that mlx4 driver restart fails, because mlx4_core is still in use.
According to module dependencies, both mlx4_en and mlx4_ib should have
been unloaded at this point
Please see log below.
This looks to be some kind of a race, as the repro is not deterministic.
Probably the en/ib modules are now mistakenly reloaded.
Any idea what could this be?
Regards,
Tariq
[root@reg-l-vrt-41016-009 ~]# /etc/init.d/openibd stop
Unloading HCA driver: [ OK ]
[root@reg-l-vrt-41016-009 ~]# /etc/init.d/openibd start
Loading HCA driver and Access Layer: [ OK ]
[root@reg-l-vrt-41016-009 ~]# /etc/init.d/openibd stop
Unloading mlx4_core [FAILED]
rmmod: ERROR: Module mlx4_core is in use
