net: tcp_memcontrol: simplify the per-memcg limit access

tcp_memcontrol replicates the global sysctl_mem limit array per cgroup,
but it only ever sets these entries to the value of the memory_allocated
page_counter limit.  Use the latter directly.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 15acc04ebdd38ec994feac9a515c4004425ac37e..6c91c1b739515305dd2be979db71030dd7215291 100644 (file)
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -89,7 +89,6 @@ struct cg_proto {
        struct page_counter     memory_allocated;       /* Current allocated memory. */
        int                     memory_pressure;
        bool                    active;
-       long                    sysctl_mem[3];
        /*
         * memcg field is used to find which memcg we belong directly
         * Each memcg struct can hold more than one cg_proto, so container_of

diff --git a/include/net/sock.h b/include/net/sock.h
index 1f15937ec20843c670a97ee4c3afd2e32b48b915..8b1f8e5d3a4881deccb115d612d70929efac10ef 100644 (file)
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1162,10 +1162,12 @@ static inline void sk_enter_memory_pressure(struct sock *sk)
 
 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
 {
-       long *prot = sk->sk_prot->sysctl_mem;
+       long limit = sk->sk_prot->sysctl_mem[index];
+
        if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
-               prot = sk->sk_cgrp->sysctl_mem;
-       return prot[index];
+               limit = min_t(long, limit, sk->sk_cgrp->memory_allocated.limit);
+
+       return limit;
 }
 
 static inline void memcg_memory_allocated_add(struct cg_proto *prot,

diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c
index 6759e0d6bba1b52815a5517ed4f71d5dd5d9aa0d..ef4268d12e43d04a75ccd75bd472cf89e8d3b16d 100644 (file)
--- a/net/ipv4/tcp_memcontrol.c
+++ b/net/ipv4/tcp_memcontrol.c
@@ -21,9 +21,6 @@ int tcp_init_cgroup(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
        if (!cg_proto)
                return 0;
 
-       cg_proto->sysctl_mem[0] = sysctl_tcp_mem[0];
-       cg_proto->sysctl_mem[1] = sysctl_tcp_mem[1];
-       cg_proto->sysctl_mem[2] = sysctl_tcp_mem[2];
        cg_proto->memory_pressure = 0;
        cg_proto->memcg = memcg;
 
@@ -54,7 +51,6 @@ EXPORT_SYMBOL(tcp_destroy_cgroup);
 static int tcp_update_limit(struct mem_cgroup *memcg, unsigned long nr_pages)
 {
        struct cg_proto *cg_proto;
-       int i;
        int ret;
 
        cg_proto = tcp_prot.proto_cgroup(memcg);
@@ -65,10 +61,6 @@ static int tcp_update_limit(struct mem_cgroup *memcg, unsigned long nr_pages)
        if (ret)
                return ret;
 
-       for (i = 0; i < 3; i++)
-               cg_proto->sysctl_mem[i] = min_t(long, nr_pages,
-                                               sysctl_tcp_mem[i]);
-
        if (!cg_proto->active) {
                /*
                 * The active flag needs to be written after the static_key