From patchwork Tue Apr 25 17:27:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13223563 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 81077C77B61 for ; Tue, 25 Apr 2023 17:27:59 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.526183.817781 (Exim 4.92) (envelope-from ) id 1prMSB-0000j2-KF; Tue, 25 Apr 2023 17:27:47 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 526183.817781; Tue, 25 Apr 2023 17:27:47 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1prMSB-0000ib-B6; Tue, 25 Apr 2023 17:27:47 +0000 Received: by outflank-mailman (input) for mailman id 526183; Tue, 25 Apr 2023 17:27:46 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1prMSA-0006fQ-Ca for xen-devel@lists.xenproject.org; Tue, 25 Apr 2023 17:27:46 +0000 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 7d5eb1e2-e38e-11ed-b223-6b7b168915f2; Tue, 25 Apr 2023 19:27:45 +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-318-brbwTRKSPLCfpDHZ0sB8ug-1; Tue, 25 Apr 2023 13:27:41 -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 9E4D928082A8; Tue, 25 Apr 2023 17:27:40 +0000 (UTC) Received: from localhost (unknown [10.39.193.242]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2173440C6E68; Tue, 25 Apr 2023 17:27:39 +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: 7d5eb1e2-e38e-11ed-b223-6b7b168915f2 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1682443664; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MVghegvQVUaizZCyEWjUSp2wGJFPOHKrCrNbSIUao8c=; b=Em/IX24eFFiHfbpx3PDpc2L6jENkaI4OWdNKG28Zks0D/3vIctydnxZ6eAUvNLbIi4Fui8 ZSleEp5JvBSOxG+CN3ftVtvTBaxbbKxmwSaIifYeWvY7C4uT9jQ14aXH6xL0aSiPGoPYqp 1B8STAZAQOSXE2RZwOMeiqspiP4vDw4= X-MC-Unique: brbwTRKSPLCfpDHZ0sB8ug-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Juan Quintela , Julia Suvorova , Kevin Wolf , xen-devel@lists.xenproject.org, eesposit@redhat.com, Richard Henderson , Fam Zheng , "Michael S. Tsirkin" , Coiby Xu , David Woodhouse , Marcel Apfelbaum , Peter Lieven , Paul Durrant , Stefan Hajnoczi , "Richard W.M. Jones" , qemu-block@nongnu.org, Stefano Garzarella , Anthony Perard , Stefan Weil , Xie Yongji , Paolo Bonzini , Aarushi Mehta , =?utf-8?q?Philippe_Mathieu-Daud?= =?utf-8?q?=C3=A9?= , Eduardo Habkost , Stefano Stabellini , Hanna Reitz , Ronnie Sahlberg Subject: [PATCH v4 09/20] block: add blk_in_drain() API Date: Tue, 25 Apr 2023 13:27:05 -0400 Message-Id: <20230425172716.1033562-10-stefanha@redhat.com> In-Reply-To: <20230425172716.1033562-1-stefanha@redhat.com> References: <20230425172716.1033562-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 The BlockBackend quiesce_counter is greater than zero during drained sections. Add an API to check whether the BlockBackend is in a drained section. The next patch will use this API. Signed-off-by: Stefan Hajnoczi --- include/sysemu/block-backend-global-state.h | 1 + block/block-backend.c | 7 +++++++ 2 files changed, 8 insertions(+) diff --git a/include/sysemu/block-backend-global-state.h b/include/sysemu/block-backend-global-state.h index 2b6d27db7c..ac7cbd6b5e 100644 --- a/include/sysemu/block-backend-global-state.h +++ b/include/sysemu/block-backend-global-state.h @@ -78,6 +78,7 @@ void blk_activate(BlockBackend *blk, Error **errp); int blk_make_zero(BlockBackend *blk, BdrvRequestFlags flags); void blk_aio_cancel(BlockAIOCB *acb); int blk_commit_all(void); +bool blk_in_drain(BlockBackend *blk); void blk_drain(BlockBackend *blk); void blk_drain_all(void); void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error, diff --git a/block/block-backend.c b/block/block-backend.c index ffd1d66f7d..42721a3592 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1266,6 +1266,13 @@ blk_check_byte_request(BlockBackend *blk, int64_t offset, int64_t bytes) return 0; } +/* Are we currently in a drained section? */ +bool blk_in_drain(BlockBackend *blk) +{ + GLOBAL_STATE_CODE(); /* change to IO_OR_GS_CODE(), if necessary */ + return qatomic_read(&blk->quiesce_counter); +} + /* To be called between exactly one pair of blk_inc/dec_in_flight() */ static void coroutine_fn blk_wait_while_drained(BlockBackend *blk) {