On 27/10/2021 10:52, Tony Lu wrote: > From: Wen Gu <guwen@xxxxxxxxxxxxxxxxx> > > A socket_wq mismatch issue may occur because of fallback. > > When use SMC to replace TCP, applications add an epoll entry into SMC > socket's wq, but kernel uses clcsock's wq instead of SMC socket's wq > once fallback occurs, which means the application's epoll fd dosen't > work anymore. I am not sure if I understand this fix completely, please explain your intentions for the changes in more detail. What I see so far: - smc_create() swaps the sk->sk_wq of the clcsocket and the new SMC socket - sets clcsocket sk->sk_wq to smcsocket->wq (why?) - sets smcsocket sk->sk_wq to clcsocket->wq (why?) - smc_switch_to_fallback() resets the clcsock sk->sk_wq to clcsocket->wq - smc_accept() sets smcsocket sk->sk_wq to clcsocket->wq when it is NOT fallback - but this was already done before in smc_create() ?? - smc_poll() now always uses clcsocket->wq for the call to sock_poll_wait() In smc_poll() the comment says that now clcsocket->wq is used for poll, whats the relation between socket->wq and socket->sk->sk_wq here?
