Re: [PATCH v4 04/21] xprtrdma: Update rkeys after transport reconnect

Anna Schumaker
2014-07-22T18:40:56Z

On 07/22/2014 10:51 AM, Chuck Lever wrote:
> Various reports of:
>
> rpcrdma_qp_async_error_upcall: QP error 3 on device mlx4_0
> ep ffff8800bfd3e848
>
> Ensure that rkeys in already-marshalled RPC/RDMA headers are
> refreshed after the QP has been replaced by a reconnect.
>
> BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=249
> Suggested-by: Selvin Xavier <Selvin.Xavier-iH1Dq9VlAzfQT0dZR+AlfA@public.gmane.org>
> Signed-off-by: Chuck Lever <chuck.lever-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
> Tested-by: Steve Wise <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
> Tested-by: Shirley Ma <shirley.ma-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
> Tested-by: Devesh Sharma <devesh.sharma-laKkSmNT4hbQT0dZR+AlfA@public.gmane.org>
> ---
> net/sunrpc/xprtrdma/rpc_rdma.c | 75 ++++++++++++++++++++-------------------
> net/sunrpc/xprtrdma/transport.c | 11 +++---
> net/sunrpc/xprtrdma/xprt_rdma.h | 10 +++++
> 3 files changed, 54 insertions(+), 42 deletions(-)
>
> diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
> index 693966d..54422f7 100644
> --- a/net/sunrpc/xprtrdma/rpc_rdma.c
> +++ b/net/sunrpc/xprtrdma/rpc_rdma.c
> @@ -53,14 +53,6 @@
> # define RPCDBG_FACILITY RPCDBG_TRANS
> #endif
>
> -enum rpcrdma_chunktype {
> - rpcrdma_noch = 0,
> - rpcrdma_readch,
> - rpcrdma_areadch,
> - rpcrdma_writech,
> - rpcrdma_replych
> -};
> -
> #ifdef RPC_DEBUG
> static const char transfertypes[][12] = {
> "pure inline", /* no chunks */
> @@ -286,6 +278,28 @@ out:
> }
>
> /*
> + * Marshal chunks. This routine returns the header length
> + * consumed by marshaling.
> + *
> + * Returns positive RPC/RDMA header size, or negative errno.
> + */
> +
> +ssize_t
> +rpcrdma_marshal_chunks(struct rpc_rqst *rqst, ssize_t result)
> +{
> + struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
> + struct rpcrdma_msg *headerp = (struct rpcrdma_msg *)req->rl_base;
> +
> + if (req->rl_rtype != rpcrdma_noch)
> + result = rpcrdma_create_chunks(rqst, &rqst->rq_snd_buf,
> + headerp, req->rl_rtype);
> + else if (req->rl_wtype != rpcrdma_noch)
> + result = rpcrdma_create_chunks(rqst, &rqst->rq_rcv_buf,
> + headerp, req->rl_wtype);
> + return result;
> +}
> +
> +/*
> * Copy write data inline.
> * This function is used for "small" requests. Data which is passed
> * to RPC via iovecs (or page list) is copied directly into the
> @@ -377,7 +391,6 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst)
> char *base;
> size_t rpclen, padlen;
> ssize_t hdrlen;
> - enum rpcrdma_chunktype rtype, wtype;
> struct rpcrdma_msg *headerp;
>
> /*
> @@ -415,13 +428,13 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst)
> * into pages; otherwise use reply chunks.
> */
> if (rqst->rq_rcv_buf.buflen <= RPCRDMA_INLINE_READ_THRESHOLD(rqst))
> - wtype = rpcrdma_noch;
> + req->rl_wtype = rpcrdma_noch;
> else if (rqst->rq_rcv_buf.page_len == 0)
> - wtype = rpcrdma_replych;
> + req->rl_wtype = rpcrdma_replych;
> else if (rqst->rq_rcv_buf.flags & XDRBUF_READ)
> - wtype = rpcrdma_writech;
> + req->rl_wtype = rpcrdma_writech;
> else
> - wtype = rpcrdma_replych;
> + req->rl_wtype = rpcrdma_replych;
>
> /*
> * Chunks needed for arguments?
> @@ -438,16 +451,16 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst)
> * TBD check NFSv4 setacl
> */
> if (rqst->rq_snd_buf.len <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst))
> - rtype = rpcrdma_noch;
> + req->rl_rtype = rpcrdma_noch;
> else if (rqst->rq_snd_buf.page_len == 0)
> - rtype = rpcrdma_areadch;
> + req->rl_rtype = rpcrdma_areadch;
> else
> - rtype = rpcrdma_readch;
> + req->rl_rtype = rpcrdma_readch;
>
> /* The following simplification is not true forever */
> - if (rtype != rpcrdma_noch && wtype == rpcrdma_replych)
> - wtype = rpcrdma_noch;
> - if (rtype != rpcrdma_noch && wtype != rpcrdma_noch) {
> + if (req->rl_rtype != rpcrdma_noch && req->rl_wtype == rpcrdma_replych)
> + req->rl_wtype = rpcrdma_noch;
> + if (req->rl_rtype != rpcrdma_noch && req->rl_wtype != rpcrdma_noch) {
> dprintk("RPC: %s: cannot marshal multiple chunk lists\n",
> __func__);

Is this still a simplification, and is it still "not true forever"?

Anna

> return -EIO;
> @@ -461,7 +474,7 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst)
> * When padding is in use and applies to the transfer, insert
> * it and change the message type.
> */
> - if (rtype == rpcrdma_noch) {
> + if (req->rl_rtype == rpcrdma_noch) {
>
> padlen = rpcrdma_inline_pullup(rqst,
> RPCRDMA_INLINE_PAD_VALUE(rqst));
> @@ -476,7 +489,7 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst)
> headerp->rm_body.rm_padded.rm_pempty[1] = xdr_zero;
> headerp->rm_body.rm_padded.rm_pempty[2] = xdr_zero;
> hdrlen += 2 * sizeof(u32); /* extra words in padhdr */
> - if (wtype != rpcrdma_noch) {
> + if (req->rl_wtype != rpcrdma_noch) {
> dprintk("RPC: %s: invalid chunk list\n",
> __func__);
> return -EIO;
> @@ -497,30 +510,18 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst)
> * on receive. Therefore, we request a reply chunk
> * for non-writes wherever feasible and efficient.
> */
> - if (wtype == rpcrdma_noch)
> - wtype = rpcrdma_replych;
> + if (req->rl_wtype == rpcrdma_noch)
> + req->rl_wtype = rpcrdma_replych;
> }
> }
>
> - /*
> - * Marshal chunks. This routine will return the header length
> - * consumed by marshaling.
> - */
> - if (rtype != rpcrdma_noch) {
> - hdrlen = rpcrdma_create_chunks(rqst,
> - &rqst->rq_snd_buf, headerp, rtype);
> - wtype = rtype; /* simplify dprintk */
> -
> - } else if (wtype != rpcrdma_noch) {
> - hdrlen = rpcrdma_create_chunks(rqst,
> - &rqst->rq_rcv_buf, headerp, wtype);
> - }
> + hdrlen = rpcrdma_marshal_chunks(rqst, hdrlen);
> if (hdrlen < 0)
> return hdrlen;
>
> dprintk("RPC: %s: %s: hdrlen %zd rpclen %zd padlen %zd"
> " headerp 0x%p base 0x%p lkey 0x%x\n",
> - __func__, transfertypes[wtype], hdrlen, rpclen, padlen,
> + __func__, transfertypes[req->rl_wtype], hdrlen, rpclen, padlen,
> headerp, base, req->rl_iov.lkey);
>
> /*
> diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c
> index 4185102..f6d280b 100644
> --- a/net/sunrpc/xprtrdma/transport.c
> +++ b/net/sunrpc/xprtrdma/transport.c
> @@ -597,13 +597,14 @@ xprt_rdma_send_request(struct rpc_task *task)
> struct rpc_xprt *xprt = rqst->rq_xprt;
> struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
> struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
> - int rc;
> + int rc = 0;
>
> - if (req->rl_niovs == 0) {
> + if (req->rl_niovs == 0)
> rc = rpcrdma_marshal_req(rqst);
> - if (rc < 0)
> - goto failed_marshal;
> - }
> + else if (r_xprt->rx_ia.ri_memreg_strategy == RPCRDMA_FRMR)
> + rc = rpcrdma_marshal_chunks(rqst, 0);
> + if (rc < 0)
> + goto failed_marshal;
>
> if (req->rl_reply == NULL) /* e.g. reconnection */
> rpcrdma_recv_buffer_get(req);
> diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
> index f3d86b2..c270e59 100644
> --- a/net/sunrpc/xprtrdma/xprt_rdma.h
> +++ b/net/sunrpc/xprtrdma/xprt_rdma.h
> @@ -99,6 +99,14 @@ struct rpcrdma_ep {
> #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit)
> #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount)
>
> +enum rpcrdma_chunktype {
> + rpcrdma_noch = 0,
> + rpcrdma_readch,
> + rpcrdma_areadch,
> + rpcrdma_writech,
> + rpcrdma_replych
> +};
> +
> /*
> * struct rpcrdma_rep -- this structure encapsulates state required to recv
> * and complete a reply, asychronously. It needs several pieces of
> @@ -192,6 +200,7 @@ struct rpcrdma_req {
> unsigned int rl_niovs; /* 0, 2 or 4 */
> unsigned int rl_nchunks; /* non-zero if chunks */
> unsigned int rl_connect_cookie; /* retry detection */
> + enum rpcrdma_chunktype rl_rtype, rl_wtype;
> struct rpcrdma_buffer *rl_buffer; /* home base for this structure */
> struct rpcrdma_rep *rl_reply;/* holder for reply buffer */
> struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];/* chunk segments */
> @@ -347,6 +356,7 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *);
> /*
> * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
> */
> +ssize_t rpcrdma_marshal_chunks(struct rpc_rqst *, ssize_t);
> int rpcrdma_marshal_req(struct rpc_rqst *);
> size_t rpcrdma_max_payload(struct rpcrdma_xprt *);
>
>