It could happen that all !SOCK_MEMALLOC sockets have buffered so much data
that we're over the global rmem limit. This will prevent SOCK_MEMALLOC buffers
from receiving data, which will prevent userspace from running, which is needed
to reduce the buffered data.
Fix this by exempting the SOCK_MEMALLOC sockets from the rmem limit.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
include/net/sock.h | 7 ++++---
net/core/sock.c | 2 +-
net/ipv4/tcp_input.c | 8 ++++----
net/sctp/ulpevent.c | 2 +-
4 files changed, 10 insertions(+), 9 deletions(-)
Index: linux-2.6/include/net/sock.h
===================================================================
--- linux-2.6.orig/include/net/sock.h
+++ linux-2.6/include/net/sock.h
@@ -800,12 +800,13 @@ static inline int sk_wmem_schedule(struc
__sk_mem_schedule(sk, size, SK_MEM_SEND);
}
-static inline int sk_rmem_schedule(struct sock *sk, int size)
+static inline int sk_rmem_schedule(struct sock *sk, struct sk_buff *skb)
{
if (!sk_has_account(sk))
return 1;
- return size <= sk->sk_forward_alloc ||
- __sk_mem_schedule(sk, size, SK_MEM_RECV);
+ return skb->truesize <= sk->sk_forward_alloc ||
+ __sk_mem_schedule(sk, skb->truesize, SK_MEM_RECV) ||
+ skb_emergency(skb);
}
static inline void sk_mem_reclaim(struct sock *sk)
Index: linux-2.6/net/core/sock.c
===================================================================
--- linux-2.6.orig/net/core/sock.c
+++ linux-2.6/net/core/sock.c
@@ -384,7 +384,7 @@ int sock_queue_rcv_skb(struct sock *sk,
if (err)
goto out;
- if (!sk_rmem_schedule(sk, skb->truesize)) {
+ if (!sk_rmem_schedule(sk, skb)) {
err = -ENOBUFS;
goto out;
}
Index: linux-2.6/net/ipv4/tcp_input.c
===================================================================
--- linux-2.6.orig/net/ipv4/tcp_input.c
+++ linux-2.6/net/ipv4/tcp_input.c
@@ -3862,9 +3862,9 @@ static void tcp_data_queue(struct sock *
queue_and_out:
if (eaten < 0 &&
(atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
- !sk_rmem_schedule(sk, skb->truesize))) {
+ !sk_rmem_schedule(sk, skb))) {
if (tcp_prune_queue(sk) < 0 ||
- !sk_rmem_schedule(sk, skb->truesize))
+ !sk_rmem_schedule(sk, skb))
goto drop;
}
skb_set_owner_r(skb, sk);
@@ -3936,9 +3936,9 @@ drop:
TCP_ECN_check_ce(tp, skb);
if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
- !sk_rmem_schedule(sk, skb->truesize)) {
+ !sk_rmem_schedule(sk, skb)) {
if (tcp_prune_queue(sk) < 0 ||
- !sk_rmem_schedule(sk, skb->truesize))
+ !sk_rmem_schedule(sk, skb))
goto drop;
}
Index: linux-2.6/net/sctp/ulpevent.c
===================================================================
--- linux-2.6.orig/net/sctp/ulpevent.c
+++ linux-2.6/net/sctp/ulpevent.c
@@ -701,7 +701,7 @@ struct sctp_ulpevent *sctp_ulpevent_make
if (rx_count >= asoc->base.sk->sk_rcvbuf) {
if ((asoc->base.sk->sk_userlocks & SOCK_RCVBUF_LOCK) ||
- (!sk_rmem_schedule(asoc->base.sk, chunk->skb->truesize)))
+ (!sk_rmem_schedule(asoc->base.sk, chunk->skb)))
goto fail;
}
--
--
