From patchwork Tue Dec 5 18:19:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13480573 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 551C2C10F05 for ; Tue, 5 Dec 2023 18:20:49 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.648183.1012279 (Exim 4.92) (envelope-from ) id 1rAa21-0002wr-N5; Tue, 05 Dec 2023 18:20:29 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 648183.1012279; Tue, 05 Dec 2023 18:20:29 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rAa21-0002wk-K7; Tue, 05 Dec 2023 18:20:29 +0000 Received: by outflank-mailman (input) for mailman id 648183; Tue, 05 Dec 2023 18:20:28 +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 1rAa20-0002wG-OM for xen-devel@lists.xenproject.org; Tue, 05 Dec 2023 18:20:28 +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 f5e9bd2f-939a-11ee-9b0f-b553b5be7939; Tue, 05 Dec 2023 19:20:26 +0100 (CET) Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-166-Jo0TQi2kMYmjMAUTVu4qcg-1; Tue, 05 Dec 2023 13:20:21 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 98D45881D35; Tue, 5 Dec 2023 18:20:20 +0000 (UTC) Received: from localhost (unknown [10.39.194.111]) by smtp.corp.redhat.com (Postfix) with ESMTP id F19A02166B31; Tue, 5 Dec 2023 18:20:19 +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: f5e9bd2f-939a-11ee-9b0f-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701800425; 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=XASdwYxqaVrj7Zfh8PNH/kQYEj4OCOxW3FbL/rilTmk=; b=RwA24PZ3499uaaQMl6J8s+HqChqLDzhexQduPKzvdJCgV1EY6FjANpyORle7Qrd82t0qoW fmnYQjYM5u5HGGfkLq4WB1W3ktZXig9fGDMTDzx9/+VyaOuaV8pCryf2pc+Mg3oxJ/XCBe LQkO6T4/gBx4ucLLhz4DLUTYZaPgdRc= X-MC-Unique: Jo0TQi2kMYmjMAUTVu4qcg-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Stefan Hajnoczi , Vladimir Sementsov-Ogievskiy , Cleber Rosa , Xie Changlong , Paul Durrant , Ari Sundholm , Jason Wang , Eric Blake , John Snow , Eduardo Habkost , Wen Congyang , Alberto Garcia , Anthony Perard , "Michael S. Tsirkin" , Stefano Stabellini , qemu-block@nongnu.org, Juan Quintela , Paolo Bonzini , Kevin Wolf , Coiby Xu , Fabiano Rosas , Hanna Reitz , Zhang Chen , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Pavel Dovgalyuk , Peter Xu , Emanuele Giuseppe Esposito , Fam Zheng , Leonardo Bras , David Hildenbrand , Li Zhijian , xen-devel@lists.xenproject.org Subject: [PATCH v2 02/14] scsi: assert that callbacks run in the correct AioContext Date: Tue, 5 Dec 2023 13:19:59 -0500 Message-ID: <20231205182011.1976568-3-stefanha@redhat.com> In-Reply-To: <20231205182011.1976568-1-stefanha@redhat.com> References: <20231205182011.1976568-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.6 Since the removal of AioContext locking, the correctness of the code relies on running requests from a single AioContext at any given time. Add assertions that verify that callbacks are invoked in the correct AioContext. Signed-off-by: Stefan Hajnoczi Reviewed-by: Kevin Wolf --- hw/scsi/scsi-disk.c | 14 ++++++++++++++ system/dma-helpers.c | 3 +++ 2 files changed, 17 insertions(+) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index 2c1bbb3530..a5048e0aaf 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -273,6 +273,10 @@ static void scsi_aio_complete(void *opaque, int ret) SCSIDiskReq *r = (SCSIDiskReq *)opaque; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + /* The request must only run in the BlockBackend's AioContext */ + assert(blk_get_aio_context(s->qdev.conf.blk) == + qemu_get_current_aio_context()); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; @@ -370,8 +374,13 @@ static void scsi_dma_complete(void *opaque, int ret) static void scsi_read_complete_noio(SCSIDiskReq *r, int ret) { + SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); uint32_t n; + /* The request must only run in the BlockBackend's AioContext */ + assert(blk_get_aio_context(s->qdev.conf.blk) == + qemu_get_current_aio_context()); + assert(r->req.aiocb == NULL); if (scsi_disk_req_check_error(r, ret, false)) { goto done; @@ -496,8 +505,13 @@ static void scsi_read_data(SCSIRequest *req) static void scsi_write_complete_noio(SCSIDiskReq *r, int ret) { + SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); uint32_t n; + /* The request must only run in the BlockBackend's AioContext */ + assert(blk_get_aio_context(s->qdev.conf.blk) == + qemu_get_current_aio_context()); + assert (r->req.aiocb == NULL); if (scsi_disk_req_check_error(r, ret, false)) { goto done; diff --git a/system/dma-helpers.c b/system/dma-helpers.c index 528117f256..9b221cf94e 100644 --- a/system/dma-helpers.c +++ b/system/dma-helpers.c @@ -119,6 +119,9 @@ static void dma_blk_cb(void *opaque, int ret) trace_dma_blk_cb(dbs, ret); + /* DMAAIOCB is not thread-safe and must be accessed only from dbs->ctx */ + assert(ctx == qemu_get_current_aio_context()); + dbs->acb = NULL; dbs->offset += dbs->iov.size;