Mon, May 02, 2016 at 06:22:18PM CEST, eric.duma...@gmail.com wrote: >On Mon, 2016-05-02 at 18:16 +0200, Jiri Pirko wrote: >> Mon, Apr 25, 2016 at 07:39:32PM CEST, eduma...@google.com wrote: >> >SOCKWQ_ASYNC_NOSPACE is tested in sock_wake_async() >> >so that a SIGIO signal is sent when needed. >> > >> >tcp_sendmsg() clears the bit. >> >tcp_poll() sets the bit when stream is not writeable. >> > >> >We can avoid two atomic operations by first checking if socket >> >is actually interested in the FASYNC business (most sockets in >> >real applications do not use AIO, but select()/poll()/epoll()) >> > >> >This also removes one cache line miss to access sk->sk_wq->flags >> >in tcp_sendmsg() >> > >> >Signed-off-by: Eric Dumazet <eduma...@google.com> >> >> I just bisected down to this. This is causing a regression for me when >> my nfs mount becomes stuck. I can easily reproduce this if you need to >> test the fix. > >What do you mean by 'when nfs mount becomes stuck' ? > >Is this patch making nfs not functional , or does it make recovery from >some nfs error bad ?
I can mount nfs on the host. But when I do something (compile a kernel module in my case), it gets stuck. Then I cannot even ssh to the machine. No messages in dmesg. I didn't debug it any further. I just bisected and verified that this patch caused this behaviour.
