From 4b1327be9fe57443295ae86fe0fcf24a18469e9f Mon Sep 17 00:00:00 2001 From: Wei Wang Date: Tue, 17 Aug 2021 12:40:03 -0700 Subject: net-memcg: pass in gfp_t mask to mem_cgroup_charge_skmem() Add gfp_t mask as an input parameter to mem_cgroup_charge_skmem(), to give more control to the networking stack and enable it to change memcg charging behavior. In the future, the networking stack may decide to avoid oom-kills when fallbacks are more appropriate. One behavior change in mem_cgroup_charge_skmem() by this patch is to avoid force charging by default and let the caller decide when and if force charging is needed through the presence or absence of __GFP_NOFAIL. Signed-off-by: Wei Wang Reviewed-by: Shakeel Butt Signed-off-by: David S. Miller --- net/core/sock.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index aada649e07e8..950f1e70dbf5 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2728,10 +2728,12 @@ int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) { struct proto *prot = sk->sk_prot; long allocated = sk_memory_allocated_add(sk, amt); + bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg; bool charged = true; - if (mem_cgroup_sockets_enabled && sk->sk_memcg && - !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt))) + if (memcg_charge && + !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt, + gfp_memcg_charge()))) goto suppress_allocation; /* Under limit. */ @@ -2785,8 +2787,14 @@ suppress_allocation: /* Fail only if socket is _under_ its sndbuf. * In this case we cannot block, so that we have to fail. */ - if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) + if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) { + /* Force charge with __GFP_NOFAIL */ + if (memcg_charge && !charged) { + mem_cgroup_charge_skmem(sk->sk_memcg, amt, + gfp_memcg_charge() | __GFP_NOFAIL); + } return 1; + } } if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged)) @@ -2794,7 +2802,7 @@ suppress_allocation: sk_memory_allocated_sub(sk, amt); - if (mem_cgroup_sockets_enabled && sk->sk_memcg) + if (memcg_charge && charged) mem_cgroup_uncharge_skmem(sk->sk_memcg, amt); return 0; -- cgit