diff options
| author |   David S. Miller <davem@davemloft.net> | 2010-08-25 02:27:49 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-08-25 02:27:49 -0700 |
| commit | ad1af0fedba14f82b240a03fe20eb9b2fdbd0357 (patch) | |
| tree | 4d53aa8bc2d9df782aa792e52670ab55c7a44d5b /net/ipv4/tcp.c | |
| parent | pxa168_eth: silence gcc warnings (diff) | |
| download | linux-dev-ad1af0fedba14f82b240a03fe20eb9b2fdbd0357.tar.xz linux-dev-ad1af0fedba14f82b240a03fe20eb9b2fdbd0357.zip | |
tcp: Combat per-cpu skew in orphan tests.
As reported by Anton Blanchard when we use
percpu_counter_read_positive() to make our orphan socket limit checks,
the check can be off by up to num_cpus_online() * batch (which is 32
by default) which on a 128 cpu machine can be as large as the default
orphan limit itself.
Fix this by doing the full expensive sum check if the optimized check
triggers.
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Diffstat (limited to 'net/ipv4/tcp.c')
| -rw-r--r-- | net/ipv4/tcp.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 176e11aaea77..197b9b77fa3e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2011,11 +2011,8 @@ adjudge_to_death: } } if (sk->sk_state != TCP_CLOSE) { - int orphan_count = percpu_counter_read_positive( - sk->sk_prot->orphan_count); - sk_mem_reclaim(sk); - if (tcp_too_many_orphans(sk, orphan_count)) { + if (tcp_too_many_orphans(sk, 0)) { if (net_ratelimit()) printk(KERN_INFO "TCP: too many of orphaned " "sockets\n"); |