From patchwork Tue Oct 5 14:32:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Emanuele Giuseppe Esposito X-Patchwork-Id: 12536943 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0AF2C433F5 for ; Tue, 5 Oct 2021 14:46:35 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 6965B60FD7 for ; Tue, 5 Oct 2021 14:46:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 6965B60FD7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:43956 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mXliC-0001wh-UL for qemu-devel@archiver.kernel.org; Tue, 05 Oct 2021 10:46:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53368) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXlX9-0003Ir-B7 for qemu-devel@nongnu.org; Tue, 05 Oct 2021 10:35:07 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:29544) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXlX7-0004lJ-3k for qemu-devel@nongnu.org; Tue, 05 Oct 2021 10:35:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1633444504; 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=EYi7W7ZB3+c84lGrXNzjB6V1jnw66hIHQV5wm8I9OAo=; b=TKTcwHb+gwrwNvNlq/ORx4tWm/wPFhdccJlxMUum88uyKIyHIw2jL1ISQDpRvPdUuVFq9N ROBZgGlY8un55HzqUTJ6nqx0j+GNWw1HNaO6Vomlxfg4tEedbAgC4OnGIadgqNlcx/FmWO OD2IcXAWvDsj5P3WJ0LJ/PkRgqNQSE8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-589-WAeRkD8vON-bd7Ap7Uwc-g-1; Tue, 05 Oct 2021 10:35:03 -0400 X-MC-Unique: WAeRkD8vON-bd7Ap7Uwc-g-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3E0EA802935; Tue, 5 Oct 2021 14:35:02 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7F2631002391; Tue, 5 Oct 2021 14:34:58 +0000 (UTC) From: Emanuele Giuseppe Esposito To: qemu-block@nongnu.org Subject: [RFC PATCH v2 11/25] include/block/blockjob.h: global state API Date: Tue, 5 Oct 2021 10:32:01 -0400 Message-Id: <20211005143215.29500-12-eesposit@redhat.com> In-Reply-To: <20211005143215.29500-1-eesposit@redhat.com> References: <20211005143215.29500-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eesposit@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=eesposit@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.066, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Fam Zheng , Vladimir Sementsov-Ogievskiy , =?utf-8?q?Daniel_P?= =?utf-8?q?=2E_Berrang=C3=A9?= , Eduardo Habkost , Juan Quintela , qemu-devel@nongnu.org, John Snow , Emanuele Giuseppe Esposito , Richard Henderson , Markus Armbruster , "Dr. David Alan Gilbert" , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Eric Blake Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" blockjob functions run always under the BQL lock. Signed-off-by: Emanuele Giuseppe Esposito --- include/block/blockjob.h | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/include/block/blockjob.h b/include/block/blockjob.h index d200f33c10..3bf384f8bf 100644 --- a/include/block/blockjob.h +++ b/include/block/blockjob.h @@ -77,6 +77,27 @@ typedef struct BlockJob { GSList *nodes; } BlockJob; +/* + * Global state (GS) API. These functions run under the BQL lock. + * + * If a function modifies the graph, it also uses drain and/or + * aio_context_acquire/release to be sure it has unique access. + * aio_context locking is needed together with BQL because of + * the thread-safe I/O API that concurrently runs and accesses + * the graph without the BQL. + * + * It is important to note that not all of these functions are + * necessarily limited to running under the BQL, but they would + * require additional auditing and may small thread-safety changes + * to move them into the I/O API. Often it's not worth doing that + * work since the APIs are only used with the BQL held at the + * moment, so they have been placed in the GS API (for now). + * + * All functions below must use this assertion: + * g_assert(qemu_in_main_thread()); + * to catch when they are accidentally called without the BQL. + */ + /** * block_job_next: * @job: A block job, or %NULL. @@ -158,6 +179,8 @@ BlockJobInfo *block_job_query(BlockJob *job, Error **errp); */ void block_job_iostatus_reset(BlockJob *job); +/* Common functions that are neither I/O nor Global State */ + /** * block_job_is_internal: * @job: The job to determine if it is user-visible or not.