From 1033990ac5b2ab6cee93734cb6d301aa3a35bcaa Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 15 Apr 2019 17:15:06 +0800 Subject: [PATCH] sctp: implement memory accounting on tx path Now when sending packets, sk_mem_charge() and sk_mem_uncharge() have been used to set sk_forward_alloc. We just need to call sk_wmem_schedule() to check if the allocated should be raised, and call sk_mem_reclaim() to check if the allocated should be reduced when it's under memory pressure. If sk_wmem_schedule() returns false, which means no memory is allowed to allocate, it will block and wait for memory to become available. Note different from tcp, sctp wait_for_buf happens before allocating any skb, so memory accounting check is done with the whole msg_len before it too. Reported-by: Matteo Croce Tested-by: Matteo Croce Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/socket.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 9874e60c9b0d..f66dca3b1055 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1913,7 +1913,10 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc, if (sctp_wspace(asoc) < (int)msg_len) sctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc)); - if (sctp_wspace(asoc) <= 0) { + if (sk_under_memory_pressure(sk)) + sk_mem_reclaim(sk); + + if (sctp_wspace(asoc) <= 0 || !sk_wmem_schedule(sk, msg_len)) { timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len); if (err) @@ -8930,7 +8933,10 @@ static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p, goto do_error; if (signal_pending(current)) goto do_interrupted; - if ((int)msg_len <= sctp_wspace(asoc)) + if (sk_under_memory_pressure(sk)) + sk_mem_reclaim(sk); + if ((int)msg_len <= sctp_wspace(asoc) && + sk_wmem_schedule(sk, msg_len)) break; /* Let another process have a go. Since we are going -- 2.30.2