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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 462FAC32774 for ; Mon, 22 Aug 2022 22:29:56 +0000 (UTC) Received: from localhost ([::1]:50406 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oQFvf-00039Z-8P for qemu-devel@archiver.kernel.org; Mon, 22 Aug 2022 18:29:55 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34460) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oQFqd-00022H-A4 for qemu-devel@nongnu.org; Mon, 22 Aug 2022 18:24:43 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:59046) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oQFqa-0004cW-7f for qemu-devel@nongnu.org; Mon, 22 Aug 2022 18:24:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661207078; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qUr6b3nJkUrWElMFR9+l2HmdOnxVRTT75yw1plr5//I=; b=fEZLZv+SaUjXPcq4Rhg1kYDkzmucTHOotGmumPEu8uaz+4VicZMH5NaQtNq1srpmEwFDof MyZj8teqMJjL5PgHt7lGtcJnGD9L3R1DVOTZEc9y1VIk+bnhM0FJ5e8Tkkl8zx/vA/vncD bA0s5HgH2C3FUzkIcSAtjrK9RTaSLQ8= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-421-ZS6eQJnmM4uLTarlS9Dp2w-1; Mon, 22 Aug 2022 18:24:34 -0400 X-MC-Unique: ZS6eQJnmM4uLTarlS9Dp2w-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AD6093802AC5; Mon, 22 Aug 2022 22:24:33 +0000 (UTC) Received: from localhost (unknown [10.39.192.66]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2A0D814152E0; Mon, 22 Aug 2022 22:24:32 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Paolo Bonzini , "Denis V. Lunev" , Peter Xu , Yanan Wang , Marcel Apfelbaum , "Richard W.M. Jones" , qemu-block@nongnu.org, John Snow , integration@gluster.org, Vladimir Sementsov-Ogievskiy , Vladimir Sementsov-Ogievskiy , David Hildenbrand , Laurent Vivier , Markus Armbruster , Raphael Norwitz , Richard Henderson , Fam Zheng , sgarzare@redhat.com, Alberto Faria , Kevin Wolf , Stefan Hajnoczi , Wen Congyang , Eric Blake , Hanna Reitz , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Eduardo Habkost , "Michael S. Tsirkin" , Thomas Huth , Jeff Cody , Xie Changlong Subject: [RFC v4 11/11] virtio-blk: use BDRV_REQ_REGISTERED_BUF optimization hint Date: Mon, 22 Aug 2022 18:24:02 -0400 Message-Id: <20220822222402.176088-12-stefanha@redhat.com> In-Reply-To: <20220822222402.176088-1-stefanha@redhat.com> References: <20220822222402.176088-1-stefanha@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Register guest RAM using BlockRAMRegistrar and set the BDRV_REQ_REGISTERED_BUF flag so block drivers can optimize memory accesses in I/O requests. This is for vdpa-blk, vhost-user-blk, and other I/O interfaces that rely on DMA mapping/unmapping. Signed-off-by: Stefan Hajnoczi --- include/hw/virtio/virtio-blk.h | 2 ++ hw/block/virtio-blk.c | 39 ++++++++++++++++++++++------------ 2 files changed, 27 insertions(+), 14 deletions(-) diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h index d311c57cca..7f589b4146 100644 --- a/include/hw/virtio/virtio-blk.h +++ b/include/hw/virtio/virtio-blk.h @@ -19,6 +19,7 @@ #include "hw/block/block.h" #include "sysemu/iothread.h" #include "sysemu/block-backend.h" +#include "sysemu/block-ram-registrar.h" #include "qom/object.h" #define TYPE_VIRTIO_BLK "virtio-blk-device" @@ -64,6 +65,7 @@ struct VirtIOBlock { struct VirtIOBlockDataPlane *dataplane; uint64_t host_features; size_t config_size; + BlockRAMRegistrar blk_ram_registrar; }; typedef struct VirtIOBlockReq { diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index e9ba752f6b..907f012c45 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -21,6 +21,7 @@ #include "hw/block/block.h" #include "hw/qdev-properties.h" #include "sysemu/blockdev.h" +#include "sysemu/block-ram-registrar.h" #include "sysemu/sysemu.h" #include "sysemu/runstate.h" #include "hw/virtio/virtio-blk.h" @@ -384,12 +385,14 @@ static void virtio_blk_handle_scsi(VirtIOBlockReq *req) } } -static inline void submit_requests(BlockBackend *blk, MultiReqBuffer *mrb, +static inline void submit_requests(VirtIOBlock *s, MultiReqBuffer *mrb, int start, int num_reqs, int niov) { + BlockBackend *blk = s->blk; QEMUIOVector *qiov = &mrb->reqs[start]->qiov; int64_t sector_num = mrb->reqs[start]->sector_num; bool is_write = mrb->is_write; + BdrvRequestFlags flags = 0; if (num_reqs > 1) { int i; @@ -420,12 +423,18 @@ static inline void submit_requests(BlockBackend *blk, MultiReqBuffer *mrb, num_reqs - 1); } + if (blk_ram_registrar_ok(&s->blk_ram_registrar)) { + flags |= BDRV_REQ_REGISTERED_BUF; + } + if (is_write) { - blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, - virtio_blk_rw_complete, mrb->reqs[start]); + blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, + flags, virtio_blk_rw_complete, + mrb->reqs[start]); } else { - blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, - virtio_blk_rw_complete, mrb->reqs[start]); + blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, + flags, virtio_blk_rw_complete, + mrb->reqs[start]); } } @@ -447,14 +456,14 @@ static int multireq_compare(const void *a, const void *b) } } -static void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb) +static void virtio_blk_submit_multireq(VirtIOBlock *s, MultiReqBuffer *mrb) { int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0; uint32_t max_transfer; int64_t sector_num = 0; if (mrb->num_reqs == 1) { - submit_requests(blk, mrb, 0, 1, -1); + submit_requests(s, mrb, 0, 1, -1); mrb->num_reqs = 0; return; } @@ -474,11 +483,11 @@ static void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb) * 3. merge would exceed maximum transfer length of backend device */ if (sector_num + nb_sectors != req->sector_num || - niov > blk_get_max_iov(blk) - req->qiov.niov || + niov > blk_get_max_iov(s->blk) - req->qiov.niov || req->qiov.size > max_transfer || nb_sectors > (max_transfer - req->qiov.size) / BDRV_SECTOR_SIZE) { - submit_requests(blk, mrb, start, num_reqs, niov); + submit_requests(s, mrb, start, num_reqs, niov); num_reqs = 0; } } @@ -494,7 +503,7 @@ static void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb) num_reqs++; } - submit_requests(blk, mrb, start, num_reqs, niov); + submit_requests(s, mrb, start, num_reqs, niov); mrb->num_reqs = 0; } @@ -509,7 +518,7 @@ static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb) * Make sure all outstanding writes are posted to the backing device. */ if (mrb->is_write && mrb->num_reqs > 0) { - virtio_blk_submit_multireq(s->blk, mrb); + virtio_blk_submit_multireq(s, mrb); } blk_aio_flush(s->blk, virtio_blk_flush_complete, req); } @@ -689,7 +698,7 @@ static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS || is_write != mrb->is_write || !s->conf.request_merging)) { - virtio_blk_submit_multireq(s->blk, mrb); + virtio_blk_submit_multireq(s, mrb); } assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS); @@ -796,7 +805,7 @@ void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq) } while (!virtio_queue_empty(vq)); if (mrb.num_reqs) { - virtio_blk_submit_multireq(s->blk, &mrb); + virtio_blk_submit_multireq(s, &mrb); } blk_io_unplug(s->blk); @@ -845,7 +854,7 @@ void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh) } if (mrb.num_reqs) { - virtio_blk_submit_multireq(s->blk, &mrb); + virtio_blk_submit_multireq(s, &mrb); } if (is_bh) { blk_dec_in_flight(s->conf.conf.blk); @@ -1227,6 +1236,7 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) } s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s); + blk_ram_registrar_init(&s->blk_ram_registrar, s->blk); blk_set_dev_ops(s->blk, &virtio_block_ops, s); blk_iostatus_enable(s->blk); @@ -1252,6 +1262,7 @@ static void virtio_blk_device_unrealize(DeviceState *dev) virtio_del_queue(vdev, i); } qemu_coroutine_dec_pool_size(conf->num_queues * conf->queue_size / 2); + blk_ram_registrar_destroy(&s->blk_ram_registrar); qemu_del_vm_change_state_handler(s->change); blockdev_mark_auto_del(s->blk); virtio_cleanup(vdev); -- 2.37.2