From patchwork Tue Nov 21 08:44:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Duan, Zhenzhong" X-Patchwork-Id: 13462619 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 1CF36C5ACB3 for ; Tue, 21 Nov 2023 08:48:12 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r5MOz-00063M-Bx; Tue, 21 Nov 2023 03:46:37 -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 1r5MOv-00062b-BF for qemu-devel@nongnu.org; Tue, 21 Nov 2023 03:46:33 -0500 Received: from mgamail.intel.com ([134.134.136.65]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r5MOt-0001Qo-0I for qemu-devel@nongnu.org; Tue, 21 Nov 2023 03:46:32 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700556391; x=1732092391; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Z+wJpLKhgIS1v006pPPmVkqIUKj3EnkrkRZBjwby9FQ=; b=afFwo/m1Z8c0T6JW5+ZS8l0wD+9JbwVjwLxzbe+GH7AiarROx0ijqpPF pWFJI4dua6uIHbaEO4m/7sKk4/P8NcOAQ2CXC2sKwPYT7S1GeyJHr4u3d zzGQTjonmm7aWdlcU1YbNEymzz6St+xhWr8yL+oVWrg1dkhzHEKzxg1/4 +h748+CkpxsvhUIg3e1yPFVkdTAOTUkf8FcskGfuOT+Xe9UO3o8qUUGDM RGIGu5Ak1R/0YyFaGRhMzvtF8rEzdHjgLioS71oX6EtrLU+cnaAtjoBRK tG2m0mzKVqnwuIP5Li0zrIKtkWVxxIG905fb/wlB+Z2w3suuaPK6vaXQG g==; X-IronPort-AV: E=McAfee;i="6600,9927,10900"; a="395721990" X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="395721990" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Nov 2023 00:46:29 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10900"; a="884124850" X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="884124850" Received: from spr-s2600bt.bj.intel.com ([10.240.192.124]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Nov 2023 00:46:25 -0800 From: Zhenzhong Duan To: qemu-devel@nongnu.org Cc: alex.williamson@redhat.com, clg@redhat.com, jgg@nvidia.com, nicolinc@nvidia.com, joao.m.martins@oracle.com, eric.auger@redhat.com, peterx@redhat.com, jasowang@redhat.com, kevin.tian@intel.com, yi.l.liu@intel.com, yi.y.sun@intel.com, chao.p.peng@intel.com Subject: [PATCH v7 03/27] vfio/common: return early if space isn't empty Date: Tue, 21 Nov 2023 16:44:02 +0800 Message-Id: <20231121084426.1286987-4-zhenzhong.duan@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231121084426.1286987-1-zhenzhong.duan@intel.com> References: <20231121084426.1286987-1-zhenzhong.duan@intel.com> MIME-Version: 1.0 Received-SPF: pass client-ip=134.134.136.65; envelope-from=zhenzhong.duan@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=-0.035, 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, 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-bounces+qemu-devel=archiver.kernel.org@nongnu.org This is a trivial optimization. If there is active container in space, vfio_reset_handler will never be unregistered. So revert the check of space->containers and return early. Signed-off-by: Zhenzhong Duan Reviewed-by: Cédric Le Goater Reviewed-by: Eric Auger Tested-by: Eric Auger --- hw/vfio/common.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 572ae7c934..934f4f5446 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -1462,10 +1462,13 @@ VFIOAddressSpace *vfio_get_address_space(AddressSpace *as) void vfio_put_address_space(VFIOAddressSpace *space) { - if (QLIST_EMPTY(&space->containers)) { - QLIST_REMOVE(space, list); - g_free(space); + if (!QLIST_EMPTY(&space->containers)) { + return; } + + QLIST_REMOVE(space, list); + g_free(space); + if (QLIST_EMPTY(&vfio_address_spaces)) { qemu_unregister_reset(vfio_reset_handler, NULL); }