| Message ID | 20230811025530.3510703-1-imagedong@tencent.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | net: tcp: support probing OOM | expand |
On Fri, Aug 11, 2023 at 5:01 AM <menglong8.dong@gmail.com> wrote: > > From: Menglong Dong <imagedong@tencent.com> > > In this series, we make some small changes to make the tcp retransmission > become zero-window probes if the receiver drops the skb because of memory > pressure. > > In the 1st patch, we reply a zero-window ACK if the skb is dropped > because out of memory, instead of dropping the skb silently. > > In the 2nd patch, we allow a zero-window ACK to update the window. > > In the 3rd patch, fix unexcepted socket die when snd_wnd is 0 in > tcp_retransmit_timer(). > > In the 4th patch, we refactor the debug message in tcp_retransmit_timer() > to make it more correct. > > After these changes, the tcp can probe the OOM of the receiver forever. > > Changes since v3: > - make the timeout "2 * TCP_RTO_MAX" in the 3rd patch > - tp->retrans_stamp is not based on jiffies and can't be compared with > icsk->icsk_timeout in the 3rd patch. Fix it. > - introduce the 4th patch > > Changes since v2: > - refactor the code to avoid code duplication in the 1st patch > - use after() instead of max() in tcp_rtx_probe0_timed_out() > > Changes since v1: > - send 0 rwin ACK for the receive queue empty case when necessary in the > 1st patch > - send the ACK immediately by using the ICSK_ACK_NOW flag in the 1st > patch > - consider the case of the connection restart from idle, as Neal comment, > in the 3rd patch SGTM, thanks. Reviewed-by: Eric Dumazet <edumazet@google.com>
Hello: This series was applied to netdev/net-next.git (main) by David S. Miller <davem@davemloft.net>: On Fri, 11 Aug 2023 10:55:26 +0800 you wrote: > From: Menglong Dong <imagedong@tencent.com> > > In this series, we make some small changes to make the tcp retransmission > become zero-window probes if the receiver drops the skb because of memory > pressure. > > In the 1st patch, we reply a zero-window ACK if the skb is dropped > because out of memory, instead of dropping the skb silently. > > [...] Here is the summary with links: - [net-next,v4,1/4] net: tcp: send zero-window ACK when no memory https://git.kernel.org/netdev/net-next/c/e2142825c120 - [net-next,v4,2/4] net: tcp: allow zero-window ACK update the window https://git.kernel.org/netdev/net-next/c/800a666141de - [net-next,v4,3/4] net: tcp: fix unexcepted socket die when snd_wnd is 0 https://git.kernel.org/netdev/net-next/c/e89688e3e978 - [net-next,v4,4/4] net: tcp: refactor the dbg message in tcp_retransmit_timer() https://git.kernel.org/netdev/net-next/c/031c44b7527a You are awesome, thank you!
From: Menglong Dong <imagedong@tencent.com> In this series, we make some small changes to make the tcp retransmission become zero-window probes if the receiver drops the skb because of memory pressure. In the 1st patch, we reply a zero-window ACK if the skb is dropped because out of memory, instead of dropping the skb silently. In the 2nd patch, we allow a zero-window ACK to update the window. In the 3rd patch, fix unexcepted socket die when snd_wnd is 0 in tcp_retransmit_timer(). In the 4th patch, we refactor the debug message in tcp_retransmit_timer() to make it more correct. After these changes, the tcp can probe the OOM of the receiver forever. Changes since v3: - make the timeout "2 * TCP_RTO_MAX" in the 3rd patch - tp->retrans_stamp is not based on jiffies and can't be compared with icsk->icsk_timeout in the 3rd patch. Fix it. - introduce the 4th patch Changes since v2: - refactor the code to avoid code duplication in the 1st patch - use after() instead of max() in tcp_rtx_probe0_timed_out() Changes since v1: - send 0 rwin ACK for the receive queue empty case when necessary in the 1st patch - send the ACK immediately by using the ICSK_ACK_NOW flag in the 1st patch - consider the case of the connection restart from idle, as Neal comment, in the 3rd patch Menglong Dong (4): net: tcp: send zero-window ACK when no memory net: tcp: allow zero-window ACK update the window net: tcp: fix unexcepted socket die when snd_wnd is 0 net: tcp: refactor the dbg message in tcp_retransmit_timer() include/net/inet_connection_sock.h | 3 ++- net/ipv4/tcp_input.c | 20 ++++++++++----- net/ipv4/tcp_output.c | 14 +++++++--- net/ipv4/tcp_timer.c | 41 ++++++++++++++++++++++-------- 4 files changed, 56 insertions(+), 22 deletions(-)