From mboxrd@z Thu Jan 1 00:00:00 1970 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.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 smtp.lore.kernel.org (Postfix) with ESMTPS id 733F2C433FE for ; Fri, 7 Oct 2022 16:32:54 +0000 (UTC) Received: from localhost ([::1]:45792 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ogqHN-0006EL-E7 for qemu-devel@archiver.kernel.org; Fri, 07 Oct 2022 12:32:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45660) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ogpvx-0006mV-ST for qemu-devel@nongnu.org; Fri, 07 Oct 2022 12:10:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:40652) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ogpvt-0005wV-Du for qemu-devel@nongnu.org; Fri, 07 Oct 2022 12:10:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1665159040; 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: in-reply-to:in-reply-to:references:references; bh=EoXnTMqZIexoxb06RHpGrCYMmI9m0D1+DbL86Revn+M=; b=Q4zJGHo4ycz1E02I5/ww2ZzcBbmouTwBqhgG7shpzmty2KG6gP8ziHt1xZXVr21K/papZE LDrbFGagjGxPB6ApONUXzfs/DXQJPpxYb60k/mEK828yhkwf2fuq5LN3cQjtebBQa/AkgS T8vCLP6CdmVlnFA+JzXJLFo+GzsLk64= 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-114-BYQUebbTP6WvSG1mnCmzhA-1; Fri, 07 Oct 2022 12:10:38 -0400 X-MC-Unique: BYQUebbTP6WvSG1mnCmzhA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8FDE6384C6C7; Fri, 7 Oct 2022 16:10:38 +0000 (UTC) Received: from redhat.com (unknown [10.39.192.109]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 16CCE1457F37; Fri, 7 Oct 2022 16:10:36 +0000 (UTC) Date: Fri, 7 Oct 2022 18:10:35 +0200 From: Kevin Wolf To: Emanuele Giuseppe Esposito Cc: qemu-block@nongnu.org, Hanna Reitz , Paolo Bonzini , John Snow , Vladimir Sementsov-Ogievskiy , Markus Armbruster , Stefan Hajnoczi , qemu-devel@nongnu.org Subject: Re: [PATCH v2 04/11] bdrv_child_try_change_aio_context: add transaction parameter Message-ID: References: <20220725122120.309236-1-eesposit@redhat.com> <20220725122120.309236-5-eesposit@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220725122120.309236-5-eesposit@redhat.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 25.07.2022 um 14:21 hat Emanuele Giuseppe Esposito geschrieben: > This enables the caller to use the same transaction to also > keep track of aiocontext changes. > > Signed-off-by: Emanuele Giuseppe Esposito What you're really doing here is factoring out the recursive phase. However, the factored out function is never used from anywhere else, so I don't understand the purpose of this patch. It feels like an unnecessary complication of the code. The commit message is unclear to me, too: Who is the caller of bdrv_child_try_change_aio_context() that it mentions, and why does it make a difference to it how the code is organised internally? Is this some artifact of changes you made and we don't need it any more now? > block.c | 31 ++++++++++++++++++++++++------ > include/block/block-global-state.h | 5 +++++ > 2 files changed, 30 insertions(+), 6 deletions(-) > > diff --git a/block.c b/block.c > index c02a628336..221bf90268 100644 > --- a/block.c > +++ b/block.c > @@ -7643,17 +7643,16 @@ int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, > * For the same reason, it temporarily holds also the new AioContext, since > * bdrv_drained_end calls BDRV_POLL_WHILE that assumes the lock is taken too. > */ > -int bdrv_child_try_change_aio_context(BlockDriverState *bs, AioContext *ctx, > - BdrvChild *ignore_child, Error **errp) > +int bdrv_child_try_change_aio_context_tran(BlockDriverState *bs, > + AioContext *ctx, > + BdrvChild *ignore_child, > + Transaction *tran, > + Error **errp) As mentioned above, this is never used anywhere else than from bdrv_child_try_change_aio_context(), so if we want to keep the patch, it should be static at least. Maybe find a better name, too, because all of the transaction related operations are in the caller. The function comment is not accurate any more either because it described the whole of bdrv_child_try_change_aio_context(), while this function only contains the recursive part. Kevin