From nobody Thu Sep 19 01:06:14 2024 Delivered-To: importer2@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer2=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1696834219979478.14596181980403; Sun, 8 Oct 2023 23:50:19 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qpk56-0006St-73; Mon, 09 Oct 2023 02:49:32 -0400 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 1qpk54-0006SM-So for qemu-devel@nongnu.org; Mon, 09 Oct 2023 02:49:30 -0400 Received: from gandalf.ozlabs.org ([150.107.74.76]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qpk51-0007IM-Jp for qemu-devel@nongnu.org; Mon, 09 Oct 2023 02:49:29 -0400 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4S3qQF47wKz4xWh; Mon, 9 Oct 2023 17:49:25 +1100 (AEDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4S3qQC16jjz4xWP; Mon, 9 Oct 2023 17:49:22 +1100 (AEDT) From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= To: qemu-devel@nongnu.org Cc: Alex Williamson , Jing Liu , =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= Subject: [PULL 6/6] vfio/pci: enable MSI-X in interrupt restoring on dynamic allocation Date: Mon, 9 Oct 2023 08:49:00 +0200 Message-ID: <20231009064900.1465361-7-clg@redhat.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231009064900.1465361-1-clg@redhat.com> References: <20231009064900.1465361-1-clg@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer2=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=150.107.74.76; envelope-from=SRS0=qD0P=FX=redhat.com=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no 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+importer2=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer2=patchew.org@nongnu.org X-ZM-MESSAGEID: 1696834222010100005 From: Jing Liu During migration restoring, vfio_enable_vectors() is called to restore enabling MSI-X interrupts for assigned devices. It sets the range from 0 to nr_vectors to kernel to enable MSI-X and the vectors unmasked in guest. During the MSI-X enabling, all the vectors within the range are allocated according to the VFIO_DEVICE_SET_IRQS ioctl. When dynamic MSI-X allocation is supported, we only want the guest unmasked vectors being allocated and enabled. Use vector 0 with an invalid fd to get MSI-X enabled, after that, all the vectors can be allocated in need. Signed-off-by: Jing Liu Reviewed-by: C=C3=A9dric Le Goater Reviewed-by: Alex Williamson Signed-off-by: C=C3=A9dric Le Goater --- hw/vfio/pci.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index ad508abd6f382d518871191017859c4c4c8fd4f9..898296fd5441b07fded7e50a53b= 2927683dd4b1a 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -402,6 +402,23 @@ static int vfio_enable_vectors(VFIOPCIDevice *vdev, bo= ol msix) int ret =3D 0, i, argsz; int32_t *fds; =20 + /* + * If dynamic MSI-X allocation is supported, the vectors to be allocat= ed + * and enabled can be scattered. Before kernel enabling MSI-X, setting + * nr_vectors causes all these vectors to be allocated on host. + * + * To keep allocation as needed, use vector 0 with an invalid fd to get + * MSI-X enabled first, then set vectors with a potentially sparse set= of + * eventfds to enable interrupts only when enabled in guest. + */ + if (msix && !vdev->msix->noresize) { + ret =3D vfio_enable_msix_no_vec(vdev); + + if (ret) { + return ret; + } + } + argsz =3D sizeof(*irq_set) + (vdev->nr_vectors * sizeof(*fds)); =20 irq_set =3D g_malloc0(argsz); --=20 2.41.0