From 931f3f4beb031cd483c1c8ab159ef1f8bdbe8888 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Thu, 14 Jan 2016 15:21:02 -0800 Subject: [PATCH] net: tcp_memcontrol: remove bogus hierarchy pressure propagation When a cgroup currently breaches its socket memory limit, it enters memory pressure mode for itself and its *ancestors*. This throttles transmission in unrelated sibling and cousin subtrees that have nothing to do with the breached limit. On the contrary, breaching a limit should make that group and its *children* enter memory pressure mode. But this happens already, albeit lazily: if an ancestor limit is breached, siblings will enter memory pressure on their own once the next packet arrives for them. So no additional hierarchy code is needed. Remove the bogus stuff. Signed-off-by: Johannes Weiner Acked-by: David S. Miller Reviewed-by: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/net/sock.h | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index 9ef3d7c984b4..d3b035c7362b 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1155,14 +1155,8 @@ static inline void sk_leave_memory_pressure(struct sock *sk) if (*memory_pressure) *memory_pressure = 0; - if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { - struct cg_proto *cg_proto = sk->sk_cgrp; - struct proto *prot = sk->sk_prot; - - for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) - cg_proto->memory_pressure = 0; - } - + if (mem_cgroup_sockets_enabled && sk->sk_cgrp) + sk->sk_cgrp->memory_pressure = 0; } static inline void sk_enter_memory_pressure(struct sock *sk) @@ -1170,13 +1164,8 @@ static inline void sk_enter_memory_pressure(struct sock *sk) if (!sk->sk_prot->enter_memory_pressure) return; - if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { - struct cg_proto *cg_proto = sk->sk_cgrp; - struct proto *prot = sk->sk_prot; - - for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) - cg_proto->memory_pressure = 1; - } + if (mem_cgroup_sockets_enabled && sk->sk_cgrp) + sk->sk_cgrp->memory_pressure = 1; sk->sk_prot->enter_memory_pressure(sk); } -- 2.20.1