From owner-svn-src-all@freebsd.org Fri Aug 3 20:04:07 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id E37B5104E687; Fri, 3 Aug 2018 20:04:06 +0000 (UTC) (envelope-from jhibbits@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 9A09D72CDF; Fri, 3 Aug 2018 20:04:06 +0000 (UTC) (envelope-from jhibbits@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 7B27625141; Fri, 3 Aug 2018 20:04:06 +0000 (UTC) (envelope-from jhibbits@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w73K46m2053250; Fri, 3 Aug 2018 20:04:06 GMT (envelope-from jhibbits@FreeBSD.org) Received: (from jhibbits@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w73K46XJ053249; Fri, 3 Aug 2018 20:04:06 GMT (envelope-from jhibbits@FreeBSD.org) Message-Id: <201808032004.w73K46XJ053249@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: jhibbits set sender to jhibbits@FreeBSD.org using -f From: Justin Hibbits Date: Fri, 3 Aug 2018 20:04:06 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r337273 - head/sys/dev/nvme X-SVN-Group: head X-SVN-Commit-Author: jhibbits X-SVN-Commit-Paths: head/sys/dev/nvme X-SVN-Commit-Revision: 337273 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Aug 2018 20:04:07 -0000 Author: jhibbits Date: Fri Aug 3 20:04:06 2018 New Revision: 337273 URL: https://svnweb.freebsd.org/changeset/base/337273 Log: nvme(4): Add bus_dmamap_sync() at the end of the request path Summary: Some architectures, in this case powerpc64, need explicit synchronization barriers vs device accesses. Prior to this change, when running 'make buildworld -j72' on a 18-core (72-thread) POWER9, I would see controller resets often. With this change, I don't see these resets messages, though another tester still does, for yet to be determined reasons, so this may not be a complete fix. Additionally, I see a ~5-10% speed up in buildworld times, likely due to not needing to reset the controller. Reviewed By: jimharris Differential Revision: https://reviews.freebsd.org/D16570 Modified: head/sys/dev/nvme/nvme_qpair.c Modified: head/sys/dev/nvme/nvme_qpair.c ============================================================================== --- head/sys/dev/nvme/nvme_qpair.c Fri Aug 3 19:24:04 2018 (r337272) +++ head/sys/dev/nvme/nvme_qpair.c Fri Aug 3 20:04:06 2018 (r337273) @@ -401,9 +401,13 @@ nvme_qpair_complete_tracker(struct nvme_qpair *qpair, req->retries++; nvme_qpair_submit_tracker(qpair, tr); } else { - if (req->type != NVME_REQUEST_NULL) + if (req->type != NVME_REQUEST_NULL) { + bus_dmamap_sync(qpair->dma_tag_payload, + tr->payload_dma_map, + BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE); bus_dmamap_unload(qpair->dma_tag_payload, tr->payload_dma_map); + } nvme_free_request(req); tr->req = NULL; @@ -487,6 +491,8 @@ nvme_qpair_process_completions(struct nvme_qpair *qpai */ return (false); + bus_dmamap_sync(qpair->dma_tag, qpair->queuemem_map, + BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE); while (1) { cpl = qpair->cpl[qpair->cq_head]; @@ -828,7 +834,16 @@ nvme_qpair_submit_tracker(struct nvme_qpair *qpair, st if (++qpair->sq_tail == qpair->num_entries) qpair->sq_tail = 0; + bus_dmamap_sync(qpair->dma_tag, qpair->queuemem_map, + BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE); +#ifndef __powerpc__ + /* + * powerpc's bus_dmamap_sync() already includes a heavyweight sync, but + * no other archs do. + */ wmb(); +#endif + nvme_mmio_write_4(qpair->ctrlr, doorbell[qpair->id].sq_tdbl, qpair->sq_tail); @@ -879,6 +894,8 @@ nvme_payload_map(void *arg, bus_dma_segment_t *seg, in tr->req->cmd.prp2 = 0; } + bus_dmamap_sync(tr->qpair->dma_tag_payload, tr->payload_dma_map, + BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE); nvme_qpair_submit_tracker(tr->qpair, tr); }