Return-Path: linux-nfs-owner@vger.kernel.org Received: from aserp1040.oracle.com ([141.146.126.69]:44558 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932511AbaFXQ0h convert rfc822-to-8bit (ORCPT ); Tue, 24 Jun 2014 12:26:37 -0400 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.2\)) Subject: Re: [PATCH v1 08/13] xprtrdma: Back off rkey when FAST_REG_MR fails From: Chuck Lever In-Reply-To: <53A99DA6.90808@gmail.com> Date: Tue, 24 Jun 2014 12:26:32 -0400 Cc: linux-rdma@vger.kernel.org, Linux NFS Mailing List Message-Id: <51111098-A9FF-4F43-8D1A-0B57BD1B952C@oracle.com> References: <20140623223201.1634.83888.stgit@manet.1015granger.net> <20140623224007.1634.55636.stgit@manet.1015granger.net> <53A99DA6.90808@gmail.com> To: Anna Schumaker Sender: linux-nfs-owner@vger.kernel.org List-ID: On Jun 24, 2014, at 11:47 AM, Anna Schumaker wrote: > On 06/23/2014 06:40 PM, Chuck Lever wrote: >> If posting a FAST_REG_MR Work Reqeust fails, or the FAST_REG WR >> flushes, revert the rkey update to avoid subsequent >> IB_WC_MW_BIND_ERR completions. >> >> Suggested-by: Steve Wise >> Signed-off-by: Chuck Lever >> --- >> net/sunrpc/xprtrdma/verbs.c | 39 +++++++++++++++++++++++++++++---------- >> 1 file changed, 29 insertions(+), 10 deletions(-) >> >> diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c >> index cef67fd..3efc007 100644 >> --- a/net/sunrpc/xprtrdma/verbs.c >> +++ b/net/sunrpc/xprtrdma/verbs.c >> @@ -61,6 +61,8 @@ >> # define RPCDBG_FACILITY RPCDBG_TRANS >> #endif >> >> +static void rpcrdma_decrement_frmr_rkey(struct rpcrdma_mw *); >> + >> /* >> * internal functions >> */ >> @@ -154,13 +156,17 @@ rpcrdma_sendcq_process_wc(struct ib_wc *wc) >> >> if (wrid == 0) >> return; >> - if (wc->status != IB_WC_SUCCESS) >> - return; >> >> fastreg = test_and_clear_bit(RPCRDMA_BIT_FASTREG, &wrid); >> mw = (struct rpcrdma_mw *)wrid; >> >> - mw->r.frmr.fr_state = fastreg ? FRMR_IS_VALID : FRMR_IS_INVALID; >> + if (wc->status == IB_WC_SUCCESS) { >> + mw->r.frmr.fr_state = fastreg ? >> + FRMR_IS_VALID : FRMR_IS_INVALID; >> + } else { >> + if (fastreg) >> + rpcrdma_decrement_frmr_rkey(mw); > > Isn't this the same as "else if (fastreg)?? Yep, those are logically equivalent. I left them separate, and left the extra braces, so it would be cleaner to add more logic in both arms of ?if (wc->status == IB_WC_SUCCESS)? in subsequent patches. Using ?switch (wc->status)? might be more future-proof. > Anna > >> + } >> } >> >> static int >> @@ -1480,6 +1486,24 @@ rpcrdma_unmap_one(struct rpcrdma_ia *ia, struct rpcrdma_mr_seg *seg) >> seg->mr_dma, seg->mr_dmalen, seg->mr_dir); >> } >> >> +static void >> +rpcrdma_increment_frmr_rkey(struct rpcrdma_mw *mw) >> +{ >> + struct ib_mr *frmr = mw->r.frmr.fr_mr; >> + u8 key = frmr->rkey & 0x000000FF; >> + >> + ib_update_fast_reg_key(frmr, ++key); >> +} >> + >> +static void >> +rpcrdma_decrement_frmr_rkey(struct rpcrdma_mw *mw) >> +{ >> + struct ib_mr *frmr = mw->r.frmr.fr_mr; >> + u8 key = frmr->rkey & 0x000000FF; >> + >> + ib_update_fast_reg_key(frmr, --key); >> +} >> + >> static int >> rpcrdma_register_frmr_external(struct rpcrdma_mr_seg *seg, >> int *nsegs, int writing, struct rpcrdma_ia *ia, >> @@ -1487,8 +1511,6 @@ rpcrdma_register_frmr_external(struct rpcrdma_mr_seg *seg, >> { >> struct rpcrdma_mr_seg *seg1 = seg; >> struct ib_send_wr invalidate_wr, frmr_wr, *bad_wr, *post_wr; >> - >> - u8 key; >> int len, pageoff; >> int i, rc; >> int seg_len; >> @@ -1552,14 +1574,10 @@ rpcrdma_register_frmr_external(struct rpcrdma_mr_seg *seg, >> rc = -EIO; >> goto out_err; >> } >> - >> - /* Bump the key */ >> - key = (u8)(seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey & 0x000000FF); >> - ib_update_fast_reg_key(seg1->mr_chunk.rl_mw->r.frmr.fr_mr, ++key); >> - >> frmr_wr.wr.fast_reg.access_flags = (writing ? >> IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE : >> IB_ACCESS_REMOTE_READ); >> + rpcrdma_increment_frmr_rkey(seg1->mr_chunk.rl_mw); >> frmr_wr.wr.fast_reg.rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey; >> DECR_CQCOUNT(&r_xprt->rx_ep); >> >> @@ -1568,6 +1586,7 @@ rpcrdma_register_frmr_external(struct rpcrdma_mr_seg *seg, >> if (rc) { >> dprintk("RPC: %s: failed ib_post_send for register," >> " status %i\n", __func__, rc); >> + rpcrdma_decrement_frmr_rkey(seg1->mr_chunk.rl_mw); >> goto out_err; >> } else { >> seg1->mr_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey; >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Chuck Lever chuck[dot]lever[at]oracle[dot]com