mirror of https://gitee.com/openkylin/linux.git
ef885afbf8
netdev_wait_allrefs() waits that all references to a device vanishes. It currently uses a _very_ pessimistic 250 ms delay between each probe. Some users reported that no more than 4 devices can be dismantled per second, this is a pretty serious problem for some setups. Most of the time, a refcount is about to be released by an RCU callback, that is still in flight because rollback_registered_many() uses a synchronize_rcu() call instead of rcu_barrier(). Problem is visible if number of online cpus is one, because synchronize_rcu() is then a no op. time to remove 50 ipip tunnels on a UP machine : before patch : real 11.910s after patch : real 1.250s Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reported-by: Octavian Purdila <opurdila@ixiacom.com> Reported-by: Benjamin LaHaise <bcrl@kvack.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| Makefile | ||
| datagram.c | ||
| dev.c | ||
| dev_addr_lists.c | ||
| drop_monitor.c | ||
| dst.c | ||
| ethtool.c | ||
| fib_rules.c | ||
| filter.c | ||
| flow.c | ||
| gen_estimator.c | ||
| gen_stats.c | ||
| iovec.c | ||
| kmap_skb.h | ||
| link_watch.c | ||
| neighbour.c | ||
| net-sysfs.c | ||
| net-sysfs.h | ||
| net-traces.c | ||
| net_namespace.c | ||
| netevent.c | ||
| netpoll.c | ||
| pktgen.c | ||
| request_sock.c | ||
| rtnetlink.c | ||
| scm.c | ||
| skbuff.c | ||
| sock.c | ||
| stream.c | ||
| sysctl_net_core.c | ||
| timestamping.c | ||
| user_dma.c | ||
| utils.c | ||