From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED698C433ED for ; Mon, 19 Apr 2021 14:56:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD1CE6113C for ; Mon, 19 Apr 2021 14:56:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234040AbhDSO5R (ORCPT ); Mon, 19 Apr 2021 10:57:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:20491 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232318AbhDSO5R (ORCPT ); Mon, 19 Apr 2021 10:57:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1618844207; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ObVjZYSIxyI5J/di0bqmYZr2dcRunTHj/u9twcOFJzA=; b=g10m42v1LQKW/tGsufgPqTkIrjzpNTIBeG5vNxb8tb++meh6Ep/G6rqiwvFtxja9aQPwb7 MQb5uKZb0dFDgJ5ZvFDU7qK5OgYqq/3tve8F8etWRLOVjwZ6sCZ+zhzncA8jDlHc3VMnNB E3NWxst6xRmvyKetH2l0jv6fa45vUmk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-281-QmVUcXs1MYyqoQOMnPEpfw-1; Mon, 19 Apr 2021 10:56:43 -0400 X-MC-Unique: QmVUcXs1MYyqoQOMnPEpfw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3FA218143FE; Mon, 19 Apr 2021 14:56:42 +0000 (UTC) Received: from localhost (unknown [10.18.25.174]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 527255D742; Mon, 19 Apr 2021 14:56:31 +0000 (UTC) Date: Mon, 19 Apr 2021 10:56:30 -0400 From: Mike Snitzer To: Christoph Hellwig , Jens Axboe Cc: dm-devel@redhat.com, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org Subject: Re: [PATCH v4 0/4] nvme: improve error handling and ana_state to work well with dm-multipath Message-ID: <20210419145630.GA5792@redhat.com> References: <20210416235329.49234-1-snitzer@redhat.com> <20210417000203.GA22241@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210417000203.GA22241@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Fri, Apr 16 2021 at 8:02pm -0400, Mike Snitzer wrote: > On Fri, Apr 16 2021 at 7:53pm -0400, > Mike Snitzer wrote: > > > Hi, > > > > This patchset reflects changes needed to make NVMe error handling and > > ANA state updates work well with dm-multipath (which always sets > > REQ_FAILFAST_TRANSPORT). > > > > RHEL8 has been carrying an older ~5.9 based version of this patchset > > (since RHEL8.3, August 2020). > > > > RHEL9 is coming, would really prefer that these changes land upstream > > rather than carry them within RHEL. > > > > All review/feedback welcome. > > > > Thanks, > > Mike > > > > v3 -> v4, less is more: > > - folded REQ_FAILFAST_TRANSPORT local retry and FAILUP patches > > - simplified nvme_failup_req(), removes needless blk_path_error() et al > > - removed comment block in nvme_decide_disposition() > > > > v2 -> v3: > > - Added Reviewed-by tags to BLK_STS_DO_NOT_RETRY patch. > > - Eliminated __nvme_end_req() and added code comment to > > nvme_failup_req() in FAILUP handling patch. > > > > Mike Snitzer (3): > > nvme: return BLK_STS_DO_NOT_RETRY if the DNR bit is set > > nvme: allow local retry and proper failover for REQ_FAILFAST_TRANSPORT > > nvme: decouple basic ANA log page re-read support from native > > multipathing > > > > drivers/nvme/host/core.c | 22 +++++++++++++++++++--- > > drivers/nvme/host/multipath.c | 16 +++++++++++----- > > drivers/nvme/host/nvme.h | 4 ++++ > > include/linux/blk_types.h | 8 ++++++++ > > 4 files changed, 42 insertions(+), 8 deletions(-) > > Sorry for all the noise, but I had a cut-and-paste issue with this cover > letter; should've said "[PATCH v4 0/4] ..." > > While I'm replying, I _think_ there is consensus that patch 1 is > worthwile and acceptable. Here is a combined diff of patches 2+3 to > illustrate just how minimalist these proposed changes are: > > diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c > index 540d6fd8ffef..83ca96292157 100644 > --- a/drivers/nvme/host/core.c > +++ b/drivers/nvme/host/core.c > @@ -299,6 +299,7 @@ enum nvme_disposition { > COMPLETE, > RETRY, > FAILOVER, > + FAILUP, > }; > > static inline enum nvme_disposition nvme_decide_disposition(struct request *req) > @@ -306,15 +307,16 @@ static inline enum nvme_disposition nvme_decide_disposition(struct request *req) > if (likely(nvme_req(req)->status == 0)) > return COMPLETE; > > - if (blk_noretry_request(req) || > + if ((req->cmd_flags & (REQ_FAILFAST_DEV | REQ_FAILFAST_DRIVER)) || > (nvme_req(req)->status & NVME_SC_DNR) || > nvme_req(req)->retries >= nvme_max_retries) > return COMPLETE; > > - if (req->cmd_flags & REQ_NVME_MPATH) { > + if (req->cmd_flags & (REQ_NVME_MPATH | REQ_FAILFAST_TRANSPORT)) { > if (nvme_is_path_error(nvme_req(req)->status) || > blk_queue_dying(req->q)) > - return FAILOVER; > + return (req->cmd_flags & REQ_NVME_MPATH) ? > + FAILOVER : FAILUP; > } else { > if (blk_queue_dying(req->q)) > return COMPLETE; > @@ -336,6 +338,14 @@ static inline void nvme_end_req(struct request *req) > blk_mq_end_request(req, status); > } > > +static inline void nvme_failup_req(struct request *req) > +{ > + nvme_update_ana(req); > + > + nvme_req(req)->status = NVME_SC_HOST_PATH_ERROR; > + nvme_end_req(req); > +} > + > void nvme_complete_rq(struct request *req) > { > trace_nvme_complete_rq(req); > @@ -354,6 +364,9 @@ void nvme_complete_rq(struct request *req) > case FAILOVER: > nvme_failover_req(req); > return; > + case FAILUP: > + nvme_failup_req(req); > + return; > } > } > EXPORT_SYMBOL_GPL(nvme_complete_rq); > diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c > index a1d476e1ac02..7d94250264aa 100644 > --- a/drivers/nvme/host/multipath.c > +++ b/drivers/nvme/host/multipath.c > @@ -65,23 +65,29 @@ void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns, > } > } > > -void nvme_failover_req(struct request *req) > +void nvme_update_ana(struct request *req) > { > struct nvme_ns *ns = req->q->queuedata; > u16 status = nvme_req(req)->status & 0x7ff; > - unsigned long flags; > - > - nvme_mpath_clear_current_path(ns); > > /* > * If we got back an ANA error, we know the controller is alive but not > - * ready to serve this namespace. Kick of a re-read of the ANA > + * ready to serve this namespace. Kick off a re-read of the ANA > * information page, and just try any other available path for now. > */ > if (nvme_is_ana_error(status) && ns->ctrl->ana_log_buf) { > set_bit(NVME_NS_ANA_PENDING, &ns->flags); > queue_work(nvme_wq, &ns->ctrl->ana_work); > } > +} > + > +void nvme_failover_req(struct request *req) > +{ > + struct nvme_ns *ns = req->q->queuedata; > + unsigned long flags; > + > + nvme_mpath_clear_current_path(ns); > + nvme_update_ana(req); > > spin_lock_irqsave(&ns->head->requeue_lock, flags); > blk_steal_bios(&ns->head->requeue_list, req); > diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h > index 07b34175c6ce..4eed8536625c 100644 > --- a/drivers/nvme/host/nvme.h > +++ b/drivers/nvme/host/nvme.h > @@ -664,6 +664,7 @@ void nvme_mpath_start_freeze(struct nvme_subsystem *subsys); > void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns, > struct nvme_ctrl *ctrl, int *flags); > void nvme_failover_req(struct request *req); > +void nvme_update_ana(struct request *req); > void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl); > int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl,struct nvme_ns_head *head); > void nvme_mpath_add_disk(struct nvme_ns *ns, struct nvme_id_ns *id); > @@ -714,6 +715,9 @@ static inline void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns, > static inline void nvme_failover_req(struct request *req) > { > } > +static inline void nvme_update_ana(struct request *req) > +{ > +} > static inline void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl) > { > } Since I sent these changes late on Friday I figured I'd try to get them on your radar. I would really appreciate timely review of this series for 5.13: https://patchwork.kernel.org/project/dm-devel/list/?series=468905 Thanks, Mike