From: Eric Dumazet <redacted>
Date: Sun, 29 Apr 2012 11:21:56 +0200

From: Eric Dumazet <edumazet@google.com>

[PATCH] net: fix sk_sockets_allocated_read_positive

Denys Fedoryshchenko reported frequent crashes on a proxy server and kindly
provided a lockdep report that explains it all :

 ...

Bug is that sk_sockets_allocated_read_positive() calls
percpu_counter_sum_positive() without BH being disabled.

This bug was added in commit 180d8cd942ce33
(foundations of per-cgroup memory pressure controlling.), since previous
code was using percpu_counter_read_positive() which is IRQ safe.

In __sk_mem_schedule() we dont need the precise count of allocated
sockets and can revert to previous behavior.

Reported-by: Denys Fedoryshchenko <redacted>
Sined-off-by: Eric Dumazet [off-list ref]

Applied, thanks.