From patchwork Tue Aug 22 07:29:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jing Liu X-Patchwork-Id: 1823959 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=kvMxvlXU; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4RVLcT3vp6z1yNm for ; Tue, 22 Aug 2023 17:31:05 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qYLqD-0005jq-2j; Tue, 22 Aug 2023 03:30:17 -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 1qYLpz-0005cd-Ox for qemu-devel@nongnu.org; Tue, 22 Aug 2023 03:30:05 -0400 Received: from mgamail.intel.com ([134.134.136.31]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qYLpw-0006Wr-DL for qemu-devel@nongnu.org; Tue, 22 Aug 2023 03:30:03 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1692689400; x=1724225400; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=5GkLkoCqRrhPFbnkLhCZrkLgHIZAwtVy/bSmP5P7hpw=; b=kvMxvlXU2LwqTZmF73izpr7jym3VlZ4EfxxkDEZ4RnAry4xZa9n+KDWl WpZlsqlapsKganjMN+eNGn8ZAaROmu/McUfk98dcXbjTreROhOOfl7OFr pjTbG9+N9IHdvoPTgYl3eiy59sin6lUtLMp8dyoxZEMk1CcMwzR688d92 8fPrD/rBg6tKGN//0UVvPML0bkk3PTE6goTCG4/L6setY8W34AsPDTrVw 5EKVDczvMQ/ffM2c3+nx3l9o+dMuHcg03qzOwMvuBiw7Q2LelbAVlrG8N uHX7FMyLHAZXZd/CxUxWzRuyAMicfuGqO4PuT5kkzLUCfiLtNFEC8z6fU w==; X-IronPort-AV: E=McAfee;i="6600,9927,10809"; a="437721823" X-IronPort-AV: E=Sophos;i="6.01,192,1684825200"; d="scan'208";a="437721823" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Aug 2023 00:29:48 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10809"; a="850502124" X-IronPort-AV: E=Sophos;i="6.01,192,1684825200"; d="scan'208";a="850502124" Received: from vmmteam.bj.intel.com ([10.240.192.110]) by fmsmga002.fm.intel.com with ESMTP; 22 Aug 2023 00:29:45 -0700 From: Jing Liu To: qemu-devel@nongnu.org Cc: alex.williamson@redhat.com, clg@redhat.com, pbonzini@redhat.com, kevin.tian@intel.com, reinette.chatre@intel.com, jing2.liu@intel.com, jing2.liu@linux.intel.com Subject: [PATCH v1 4/4] vfio/pci: enable MSI-X in interrupt restoring on dynamic allocation Date: Tue, 22 Aug 2023 03:29:27 -0400 Message-Id: <20230822072927.224803-5-jing2.liu@intel.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20230822072927.224803-1-jing2.liu@intel.com> References: <20230822072927.224803-1-jing2.liu@intel.com> MIME-Version: 1.0 Received-SPF: pass client-ip=134.134.136.31; envelope-from=jing2.liu@intel.com; helo=mgamail.intel.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=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org 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 --- Changes since RFC v1: - Revise the comments. (Alex) - Call the new helper function in previous patch to enable MSI-X. (Alex) --- hw/vfio/pci.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index e24c21241a0c..3c37d036e727 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -408,6 +408,23 @@ static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool msix) int ret = 0, i, argsz; int32_t *fds; + /* + * If dynamic MSI-X allocation is supported, the vectors to be allocated + * 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 = vfio_enable_msix_no_vec(vdev); + + if (ret) { + return ret; + } + } + argsz = sizeof(*irq_set) + (vdev->nr_vectors * sizeof(*fds)); irq_set = g_malloc0(argsz);