From patchwork Mon Jul 25 12:21:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Emanuele Giuseppe Esposito X-Patchwork-Id: 1660328 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=HFGZNFeX; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) 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 bilbo.ozlabs.org (Postfix) with ESMTPS id 4Lrzhg6tDTz9sB4 for ; Mon, 25 Jul 2022 22:22:59 +1000 (AEST) Received: from localhost ([::1]:52980 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oFx6v-0003DW-Q7 for incoming@patchwork.ozlabs.org; Mon, 25 Jul 2022 08:22:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48694) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oFx5c-0002Yv-DJ for qemu-devel@nongnu.org; Mon, 25 Jul 2022 08:21:38 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:47322) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oFx5Z-00062t-0o for qemu-devel@nongnu.org; Mon, 25 Jul 2022 08:21:34 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1658751691; 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=ibePkfzDt/wBtcTJ6xHX6w7CbYK24Namjfp2PXdQc0k=; b=HFGZNFeXvb6dWUd5i3xYaORMyf86JffqOL5kHaAb9EXd3tKJOWgiSpt3zNTq7bu+ZMKv4m ayxHe5pRE+bvmAgBJ4Ceb1fYJdTJmwQaCPkHIw6wPmPyOSWj8gqwyAoEpvNp2t9Bhu4W/u u6TvrPiBALfi2+XOyaGy8/eqXNzmUPM= 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-644-9eFepM5zO3ma0__2V5EVvg-1; Mon, 25 Jul 2022 08:21:28 -0400 X-MC-Unique: 9eFepM5zO3ma0__2V5EVvg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6437D1C05AAB; Mon, 25 Jul 2022 12:21:25 +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 CCB8518EB5; Mon, 25 Jul 2022 12:21:24 +0000 (UTC) From: Emanuele Giuseppe Esposito To: qemu-block@nongnu.org Cc: Kevin Wolf , Hanna Reitz , Paolo Bonzini , John Snow , Vladimir Sementsov-Ogievskiy , Markus Armbruster , Stefan Hajnoczi , qemu-devel@nongnu.org, Emanuele Giuseppe Esposito Subject: [PATCH v2 07/11] block-backend: implement .change_aio_ctx in child_root Date: Mon, 25 Jul 2022 08:21:16 -0400 Message-Id: <20220725122120.309236-8-eesposit@redhat.com> In-Reply-To: <20220725122120.309236-1-eesposit@redhat.com> References: <20220725122120.309236-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=eesposit@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" blk_root_change_aio_ctx() is very similar to blk_root_can_set_aio_ctx(), but implements a new transaction so that if all check pass, the new transaction's .commit will take care of changing the BlockBackend AioContext. blk_root_set_aio_ctx_commit() is the same as blk_root_set_aio_ctx(). Note: bdrv_child_try_change_aio_context() is not called by anyone at this point. Signed-off-by: Emanuele Giuseppe Esposito Reviewed-by: Kevin Wolf --- block/block-backend.c | 52 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/block/block-backend.c b/block/block-backend.c index f425b00793..b4951c6e21 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -138,6 +138,9 @@ static bool blk_root_can_set_aio_ctx(BdrvChild *child, AioContext *ctx, GSList **ignore, Error **errp); static void blk_root_set_aio_ctx(BdrvChild *child, AioContext *ctx, GSList **ignore); +static bool blk_root_change_aio_ctx(BdrvChild *child, AioContext *ctx, + GHashTable *visited, Transaction *tran, + Error **errp); static char *blk_root_get_parent_desc(BdrvChild *child) { @@ -336,6 +339,7 @@ static const BdrvChildClass child_root = { .can_set_aio_ctx = blk_root_can_set_aio_ctx, .set_aio_ctx = blk_root_set_aio_ctx, + .change_aio_ctx = blk_root_change_aio_ctx, .get_parent_aio_context = blk_root_get_parent_aio_context, }; @@ -2208,6 +2212,54 @@ int blk_set_aio_context(BlockBackend *blk, AioContext *new_context, return blk_do_set_aio_context(blk, new_context, true, errp); } +typedef struct BdrvStateBlkRootContext { + AioContext *new_ctx; + BlockBackend *blk; +} BdrvStateBlkRootContext; + +static void blk_root_set_aio_ctx_commit(void *opaque) +{ + BdrvStateBlkRootContext *s = opaque; + BlockBackend *blk = s->blk; + + blk_do_set_aio_context(blk, s->new_ctx, false, &error_abort); +} + +static TransactionActionDrv set_blk_root_context = { + .commit = blk_root_set_aio_ctx_commit, + .clean = g_free, +}; + +static bool blk_root_change_aio_ctx(BdrvChild *child, AioContext *ctx, + GHashTable *visited, Transaction *tran, + Error **errp) +{ + BlockBackend *blk = child->opaque; + BdrvStateBlkRootContext *s; + + if (!blk->allow_aio_context_change) { + /* + * Manually created BlockBackends (those with a name) that are not + * attached to anything can change their AioContext without updating + * their user; return an error for others. + */ + if (!blk->name || blk->dev) { + /* TODO Add BB name/QOM path */ + error_setg(errp, "Cannot change iothread of active block backend"); + return false; + } + } + + s = g_new(BdrvStateBlkRootContext, 1); + *s = (BdrvStateBlkRootContext) { + .new_ctx = ctx, + .blk = blk, + }; + + tran_add(tran, &set_blk_root_context, s); + return true; +} + static bool blk_root_can_set_aio_ctx(BdrvChild *child, AioContext *ctx, GSList **ignore, Error **errp) {