From patchwork Tue May 16 19:02:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13243523 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.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 20120C77B7A for ; Tue, 16 May 2023 19:03:14 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.535456.833188 (Exim 4.92) (envelope-from ) id 1pyzwt-00031b-B5; Tue, 16 May 2023 19:03:03 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 535456.833188; Tue, 16 May 2023 19:03:03 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pyzwt-00031R-7n; Tue, 16 May 2023 19:03:03 +0000 Received: by outflank-mailman (input) for mailman id 535456; Tue, 16 May 2023 19:03:02 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pyzws-0002US-CU for xen-devel@lists.xenproject.org; Tue, 16 May 2023 19:03:02 +0000 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 4699fd0f-f41c-11ed-8611-37d641c3527e; Tue, 16 May 2023 21:03:00 +0200 (CEST) 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-392-bwAvUUZhPMqJaK6CQaIk6A-1; Tue, 16 May 2023 15:02:54 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BEB543C0BE32; Tue, 16 May 2023 19:02:51 +0000 (UTC) Received: from localhost (unknown [10.39.192.44]) by smtp.corp.redhat.com (Postfix) with ESMTP id 246F840C6EC4; Tue, 16 May 2023 19:02:50 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 4699fd0f-f41c-11ed-8611-37d641c3527e DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684263779; 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: in-reply-to:in-reply-to:references:references; bh=eWBF29RQlo3PxqGi5ARBdz9mjgsC7oCE+g384OxkQik=; b=VOvraVyB+bdgJf0piH3fnCVkPy5nfh7XTuZrZD2kLQ2hVAoYmRLJKV1Vr94t7sHfXZKGMC EwJwLp2PRPLSqmMNfoE9u1CctwpKfcp4MKnNtTWAEjcZV9uP9uUtuUae89fNoP1caH08e5 1aEm6XAqr306+t/cvN3VqgQ8QJTtIG4= X-MC-Unique: bwAvUUZhPMqJaK6CQaIk6A-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Coiby Xu , Marcel Apfelbaum , "Michael S. Tsirkin" , "Richard W.M. Jones" , Peter Xu , xen-devel@lists.xenproject.org, Kevin Wolf , Ronnie Sahlberg , Stefano Stabellini , Richard Henderson , Stefan Hajnoczi , Julia Suvorova , Hanna Reitz , Leonardo Bras , eesposit@redhat.com, Fam Zheng , Aarushi Mehta , David Woodhouse , Xie Yongji , Stefano Garzarella , qemu-block@nongnu.org, Eduardo Habkost , Paul Durrant , Stefan Weil , Anthony Perard , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Peter Lieven , Paolo Bonzini , =?utf-8?q?P?= =?utf-8?q?hilippe_Mathieu-Daud=C3=A9?= , Juan Quintela Subject: [PATCH v6 02/20] hw/qdev: introduce qdev_is_realized() helper Date: Tue, 16 May 2023 15:02:20 -0400 Message-Id: <20230516190238.8401-3-stefanha@redhat.com> In-Reply-To: <20230516190238.8401-1-stefanha@redhat.com> References: <20230516190238.8401-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Add a helper function to check whether the device is realized without requiring the Big QEMU Lock. The next patch adds a second caller. The goal is to avoid spreading DeviceState field accesses throughout the code. Suggested-by: Philippe Mathieu-Daudé Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Stefan Hajnoczi Reviewed-by: Kevin Wolf --- include/hw/qdev-core.h | 17 ++++++++++++++--- hw/scsi/scsi-bus.c | 3 +-- 2 files changed, 15 insertions(+), 5 deletions(-) diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h index 7623703943..f1070d6dc7 100644 --- a/include/hw/qdev-core.h +++ b/include/hw/qdev-core.h @@ -1,6 +1,7 @@ #ifndef QDEV_CORE_H #define QDEV_CORE_H +#include "qemu/atomic.h" #include "qemu/queue.h" #include "qemu/bitmap.h" #include "qemu/rcu.h" @@ -168,9 +169,6 @@ typedef struct { /** * DeviceState: - * @realized: Indicates whether the device has been fully constructed. - * When accessed outside big qemu lock, must be accessed with - * qatomic_load_acquire() * @reset: ResettableState for the device; handled by Resettable interface. * * This structure should not be accessed directly. We declare it here @@ -339,6 +337,19 @@ DeviceState *qdev_new(const char *name); */ DeviceState *qdev_try_new(const char *name); +/** + * qdev_is_realized: + * @dev: The device to check. + * + * May be called outside big qemu lock. + * + * Returns: %true% if the device has been fully constructed, %false% otherwise. + */ +static inline bool qdev_is_realized(DeviceState *dev) +{ + return qatomic_load_acquire(&dev->realized); +} + /** * qdev_realize: Realize @dev. * @dev: device to realize diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c index 3c20b47ad0..8857ff41f6 100644 --- a/hw/scsi/scsi-bus.c +++ b/hw/scsi/scsi-bus.c @@ -60,8 +60,7 @@ static SCSIDevice *do_scsi_device_find(SCSIBus *bus, * the user access the device. */ - if (retval && !include_unrealized && - !qatomic_load_acquire(&retval->qdev.realized)) { + if (retval && !include_unrealized && !qdev_is_realized(&retval->qdev)) { retval = NULL; }