foundations of per-cgroup memory pressure controlling.

This patch replaces all uses of struct sock fields' memory_pressure,
memory_allocated, sockets_allocated, and sysctl_mem to acessor
macros. Those macros can either receive a socket argument, or a mem_cgroup
argument, depending on the context they live in.

Since we're only doing a macro wrapping here, no performance impact at all is
expected in the case where we don't have cgroups disabled.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index cf3068038942..8c8de2780c7a 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1922,7 +1922,7 @@ u32 __tcp_select_window(struct sock *sk)
         if (free_space < (full_space >> 1)) {
                 icsk->icsk_ack.quick = 0;
 
-                if (tcp_memory_pressure)
+                if (sk_under_memory_pressure(sk))
                         tp->rcv_ssthresh = min(tp->rcv_ssthresh,
                                                4U * tp->advmss);