Re: [PATCH] RDMA/siw: Mark expected switch fall-throughs

["Bernard Metzler" <BMT@zurich.ibm.com>]

-----"Gustavo A. R. Silva" <gustavo@embeddedor.com> wrote: -----

>To: "Bernard Metzler" <bmt@zurich.ibm.com>, "Doug Ledford"
><dledford@redhat.com>, "Jason Gunthorpe" <jgg@ziepe.ca>
>From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
>Date: 07/11/2019 06:12PM
>Cc: linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org,
>"Gustavo A. R. Silva" <gustavo@embeddedor.com>
>Subject: [EXTERNAL] [PATCH] RDMA/siw: Mark expected switch
>fall-throughs
>
>In preparation to enabling -Wimplicit-fallthrough, mark switch
>cases where we are expecting to fall through.
>
>This patch fixes the following warnings:
>
>drivers/infiniband/sw/siw/siw_qp_rx.c: In function
>‘siw_rdmap_complete’:
>drivers/infiniband/sw/siw/siw_qp_rx.c:1214:18: warning: this
>statement may fall through [-Wimplicit-fallthrough=]
>   wqe->rqe.flags |= SIW_WQE_SOLICITED;
>   ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
>drivers/infiniband/sw/siw/siw_qp_rx.c:1215:2: note: here
>  case RDMAP_SEND:
>  ^~~~
>
>drivers/infiniband/sw/siw/siw_qp_tx.c: In function
>‘siw_qp_sq_process’:
>drivers/infiniband/sw/siw/siw_qp_tx.c:1044:4: warning: this statement
>may fall through [-Wimplicit-fallthrough=]
>    siw_wqe_put_mem(wqe, tx_type);
>    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>drivers/infiniband/sw/siw/siw_qp_tx.c:1045:3: note: here
>   case SIW_OP_INVAL_STAG:
>   ^~~~
>drivers/infiniband/sw/siw/siw_qp_tx.c:1128:4: warning: this statement
>may fall through [-Wimplicit-fallthrough=]
>    siw_wqe_put_mem(wqe, tx_type);
>    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>drivers/infiniband/sw/siw/siw_qp_tx.c:1129:3: note: here
>   case SIW_OP_INVAL_STAG:
>   ^~~~
>
>Warning level 3 was used: -Wimplicit-fallthrough=3
>
>This patch is part of the ongoing efforts to enable
>-Wimplicit-fallthrough.
>
>Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
>---
>
>NOTE: -Wimplicit-fallthrough will be enabled globally in v5.3. So, I
>      suggest you to take this patch for 5.3-rc1.
>
> drivers/infiniband/sw/siw/siw_qp_rx.c | 2 ++
> drivers/infiniband/sw/siw/siw_qp_tx.c | 4 ++++
> 2 files changed, 6 insertions(+)
>
>diff --git a/drivers/infiniband/sw/siw/siw_qp_rx.c
>b/drivers/infiniband/sw/siw/siw_qp_rx.c
>index 682a290bc11e..f87657a11657 100644
>--- a/drivers/infiniband/sw/siw/siw_qp_rx.c
>+++ b/drivers/infiniband/sw/siw/siw_qp_rx.c
>@@ -1212,6 +1212,8 @@ static int siw_rdmap_complete(struct siw_qp
>*qp, int error)
> 	case RDMAP_SEND_SE:
> 	case RDMAP_SEND_SE_INVAL:
> 		wqe->rqe.flags |= SIW_WQE_SOLICITED;
>+		/* Fall through */
>+
> 	case RDMAP_SEND:
> 	case RDMAP_SEND_INVAL:
> 		if (wqe->wr_status == SIW_WR_IDLE)
>diff --git a/drivers/infiniband/sw/siw/siw_qp_tx.c
>b/drivers/infiniband/sw/siw/siw_qp_tx.c
>index f0d949e2e318..43020d2040fc 100644
>--- a/drivers/infiniband/sw/siw/siw_qp_tx.c
>+++ b/drivers/infiniband/sw/siw/siw_qp_tx.c
>@@ -1042,6 +1042,8 @@ int siw_qp_sq_process(struct siw_qp *qp)
> 		case SIW_OP_SEND_REMOTE_INV:
> 		case SIW_OP_WRITE:
> 			siw_wqe_put_mem(wqe, tx_type);
>+			/* Fall through */
>+
> 		case SIW_OP_INVAL_STAG:
> 		case SIW_OP_REG_MR:
> 			if (tx_flags(wqe) & SIW_WQE_SIGNALLED)
>@@ -1126,6 +1128,8 @@ int siw_qp_sq_process(struct siw_qp *qp)
> 		case SIW_OP_READ:
> 		case SIW_OP_READ_LOCAL_INV:
> 			siw_wqe_put_mem(wqe, tx_type);
>+			/* Fall through */
>+
> 		case SIW_OP_INVAL_STAG:
> 		case SIW_OP_REG_MR:
> 			siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
>-- 
>2.21.0
>
>
Thanks Gustavo. Didn't know that becomes mandatory. Had it here and there
only, where I thought it is not obvious...but better to keep the rules
simple.

Thanks,
Bernard.