Re: [PATCH net 1/2] net/smc: non blocking recvmsg() return -EAGAIN when no data and signal_pending

From: Tony Lu
Date: Mon May 09 2022 - 23:23:41 EST


On Mon, May 09, 2022 at 07:58:36PM +0800, Guangguan Wang wrote:
> Non blocking sendmsg will return -EAGAIN when any signal pending
> and no send space left, while non blocking recvmsg return -EINTR
> when signal pending and no data received. This may makes confused.
> As TCP returns -EAGAIN in the conditions descriped above. Align the

A little typo descriped -> described.

> behavior of smc with TCP.

I also agree with the behavior of aligning TCP.

Fixes tag is preferred:

Fixes: 846e344eb722 ("net/smc: add receive timeout check")

> Signed-off-by: Guangguan Wang <guangguan.wang@xxxxxxxxxxxxxxxxx>

Reviewed-by: Tony Lu <tonylu@xxxxxxxxxxxxxxxxx>

Thanks,
Tony Lu

> ---
> net/smc/smc_rx.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/net/smc/smc_rx.c b/net/smc/smc_rx.c
> index 51e8eb2933ff..338b9ef806e8 100644
> --- a/net/smc/smc_rx.c
> +++ b/net/smc/smc_rx.c
> @@ -355,12 +355,12 @@ int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg,
> }
> break;
> }
> + if (!timeo)
> + return -EAGAIN;
> if (signal_pending(current)) {
> read_done = sock_intr_errno(timeo);
> break;
> }
> - if (!timeo)
> - return -EAGAIN;
> }
>
> if (!smc_rx_data_available(conn)) {
> --
> 2.24.3 (Apple Git-128)