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 6C85AC369C9 for ; Thu, 17 Apr 2025 20:58:03 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u5WJ4-0006qP-CW; Thu, 17 Apr 2025 16:57:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u5WJ2-0006q6-2s for qemu-devel@nongnu.org; Thu, 17 Apr 2025 16:57:56 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u5WJ0-0000Ju-Em for qemu-devel@nongnu.org; Thu, 17 Apr 2025 16:57:55 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744923473; 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=By0pqF9HHt1jfje6Gnvqecv6EzMnY1kW+Nvv25KMZRU=; b=JXfd3Wh+9f4mKvOz+/12OZPVQi0MWLD3VJluc3hjNqTf0xxUb5KPrJh0uGhRkyETqQB0G3 MFlkR+bWb/PKuWiiuqkEnuUJDIsmHd8E8vpGtOQ3SSpu8Vx6mDMGeWozEdW9aIyXPhAMiZ dqUxgvu9ralt1S4hFcQKufXP9f9j9DQ= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-587-n6FWT4htPIeiXFsT1k5CUQ-1; Thu, 17 Apr 2025 16:57:51 -0400 X-MC-Unique: n6FWT4htPIeiXFsT1k5CUQ-1 X-Mimecast-MFC-AGG-ID: n6FWT4htPIeiXFsT1k5CUQ_1744923470 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (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 mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id EEAE31956048; Thu, 17 Apr 2025 20:57:48 +0000 (UTC) Received: from localhost (unknown [10.2.16.64]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 361BD19560BA; Thu, 17 Apr 2025 20:57:48 +0000 (UTC) Date: Thu, 17 Apr 2025 16:57:46 -0400 From: Stefan Hajnoczi To: Eric Blake Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, vsementsov@yandex-team.ru, John Snow , Kevin Wolf , Hanna Reitz , Markus Armbruster Subject: Re: [PATCH v2 11/11] mirror: Allow QMP override to declare target already zero Message-ID: <20250417205746.GJ85491@fedora> References: <20250417184133.105746-13-eblake@redhat.com> <20250417184133.105746-24-eblake@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="Ujn3Q0f/nmaJ/vfQ" Content-Disposition: inline In-Reply-To: <20250417184133.105746-24-eblake@redhat.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@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, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=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: 2.1.29 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-bounces+qemu-devel=archiver.kernel.org@nongnu.org --Ujn3Q0f/nmaJ/vfQ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Apr 17, 2025 at 01:39:16PM -0500, Eric Blake wrote: > QEMU's attempts to learn whether a destination file starts life with > all zero contents are just a heuristic. There may be cases where the > caller is aware of information that QEMU cannot learn quickly, in > which case telling QEMU what to assume about the destination can make > the mirror operation faster. Given our existing example of "qemu-img > convert --target-is-zero", it is time to expose this override in QMP > for blockdev-mirror as well. >=20 > Signed-off-by: Eric Blake > --- > qapi/block-core.json | 8 +++++++- > include/block/block_int-global-state.h | 3 ++- > block/mirror.c | 23 +++++++++++++++-------- > blockdev.c | 18 +++++++++++------- > tests/unit/test-block-iothread.c | 2 +- > 5 files changed, 36 insertions(+), 18 deletions(-) Reviewed-by: Stefan Hajnoczi --Ujn3Q0f/nmaJ/vfQ Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQEzBAEBCgAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmgBa0oACgkQnKSrs4Gr c8gyuQgAyLy17ad1fblZiOAjlqqbEaB2wMWByexXA+vle+dkJrA+BcnFOp8Hh+xY H1XHUIYRNHVEVvajerdscn98YGUSkNHMplERH5MlB1snuLOYsu2Dj77CeGB7YF5E /xnMq3fIGRZm4mOz2g7JpWHv5MBN+rCIk4wbyqMSU2XXsxKH0qZAh+4zdcMRdTtC LtWlG4B/pqoqjCarWAa6yWT2UBNDL/DSeA4Wph8Rwi/B/KwxvWeQNzuQeEEeDAE1 kfGZBCJr7YEwJ+KWtVhZcqV2nVVEtBO9WBL28J9giI14crHxz+CjNBJWDGZmiPYX rzjJ4I0s3SGPg/T5RJbWz165QMSahQ== =iC6R -----END PGP SIGNATURE----- --Ujn3Q0f/nmaJ/vfQ--