From patchwork Fri Feb 2 15:31:55 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 13543042 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 BEA91C48291 for ; Fri, 2 Feb 2024 15:33:10 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rVvWm-0003vq-Km; Fri, 02 Feb 2024 10:32:28 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rVvWj-0003vF-RU for qemu-devel@nongnu.org; Fri, 02 Feb 2024 10:32:25 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rVvWi-0000C3-EH for qemu-devel@nongnu.org; Fri, 02 Feb 2024 10:32:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1706887943; 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: content-transfer-encoding:content-transfer-encoding; bh=nTVW0ex8r7dGzT2U4Ccj8kElbtM0N6FAXXTnFzTz3so=; b=hvq1Y2EqHXo+D/qQToSP4CZcFxU1DutfntOf1ffzqN0OjSviZe/4dDMZdfO14DdFQvGKxe JPp00JDqzbGGSa7XrkHRJIgZ8liCXUhGr0Zw1RgqerTYKhFek88NziFIxDJpvVG13MdvuW fD0meWmvjJO0RQ2pYyq4z0z68Sj7xAE= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-206-DjKHpWLeNNOYxbLs4s7pJQ-1; Fri, 02 Feb 2024 10:32:20 -0500 X-MC-Unique: DjKHpWLeNNOYxbLs4s7pJQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 61CDE85CBA4; Fri, 2 Feb 2024 15:32:20 +0000 (UTC) Received: from localhost (unknown [10.39.194.28]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B2E193C2E; Fri, 2 Feb 2024 15:32:19 +0000 (UTC) From: Hanna Czenczek To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Hanna Czenczek , qemu-stable@nongnu.org, Stefan Hajnoczi , Fiona Ebner , Paolo Bonzini , Kevin Wolf , "Michael S . Tsirkin" , Fam Zheng Subject: [PATCH v2 0/3] virtio: Re-enable notifications after drain Date: Fri, 2 Feb 2024 16:31:55 +0100 Message-ID: <20240202153158.788922-1-hreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.1 Received-SPF: pass client-ip=170.10.133.124; envelope-from=hreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.276, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable 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-bounces+qemu-devel=archiver.kernel.org@nongnu.org v1: https://lists.nongnu.org/archive/html/qemu-block/2024-01/msg00336.html Hi, This is basically the same series as v1: When using aio_set_event_notifier_poll(), the io_poll_end() callback is only invoked when polling ends, not when the notifier is being removed while in a polling section. This can leave the virtqueue notifier disabled during drained sections, which however is not a bad thing. We just need to ensure they are re-enabled after the drain, and kick the virtqueue once to pick up all the requests that came in during the drained section. Patch 1 is a technically unrelated fix, but addresses a problem that became visible with patch 2 applied. Patch 3 is a small (optional) clean-up patch. v2: - Changed the title of this series and patch 2 (was: "Keep notifications disabled durin drain"): Keeping the notifier disabled was something the initial RFC did, this version (v1 too) just ensures the notifier is enabled after the drain, regardless of its state before. - Use event_notifier_set() instead of virtio_queue_notify() in patch 2 - Added patch 3 Hanna Czenczek (3): virtio-scsi: Attach event vq notifier with no_poll virtio: Re-enable notifications after drain virtio-blk: Use ioeventfd_attach in start_ioeventfd include/block/aio.h | 7 ++++++- hw/block/virtio-blk.c | 21 ++++++++++----------- hw/scsi/virtio-scsi.c | 7 ++++++- hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 64 insertions(+), 13 deletions(-) Reviewed-by: Stefan Hajnoczi