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spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:38538 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lj0dD-0004CM-Qu for qemu-devel@archiver.kernel.org; Tue, 18 May 2021 10:23:35 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47498) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lj0c8-0003NC-EJ for qemu-devel@nongnu.org; Tue, 18 May 2021 10:22:28 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:57136) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lj0c6-0006eG-6y for qemu-devel@nongnu.org; Tue, 18 May 2021 10:22:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621347745; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7B1ygcbckd/zrvK+m0062hXljsq5SHFTNYdbLSGC81o=; b=h1O2SIdQWqnefcHUEZlX+yq9DltbHTsbJ7CqoTUGVOgh9+l5aL20J3YeHGuKB8heC6g/Hl 0GZufk0UF4h03+HP2K7jrVvmRAd8En+wz7ikPkT0a/nnedspVlEED++zwp+y9mRtT/O8Nu dyaUpTUYQnEACkdHvyelpitA4fvD7wE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-303-ZhUhj_l2NhGxvI22S5epJg-1; Tue, 18 May 2021 10:22:23 -0400 X-MC-Unique: ZhUhj_l2NhGxvI22S5epJg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A63A7107ACF5; Tue, 18 May 2021 14:22:22 +0000 (UTC) Received: from dresden.str.redhat.com (ovpn-115-121.ams2.redhat.com [10.36.115.121]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3A5B41349A; Tue, 18 May 2021 14:22:19 +0000 (UTC) Subject: Re: [PATCH 17/21] block/block-copy: switch to fully set bitmap by default To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20210517064428.16223-1-vsementsov@virtuozzo.com> <20210517064428.16223-19-vsementsov@virtuozzo.com> From: Max Reitz Message-ID: Date: Tue, 18 May 2021 16:22:16 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210517064428.16223-19-vsementsov@virtuozzo.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.374, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, berrange@redhat.com, ehabkost@redhat.com, jsnow@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com, den@openvz.org, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 17.05.21 08:44, Vladimir Sementsov-Ogievskiy wrote: > block-copy has a bit inconvenient interface around dirty bitmap: user > should get pointer to it and than set by hand. We do need a possibility > to share the bitmap with backup job. > > But default of empty bitmap is strange. I don’t know, I don’t find it strange. It expects its user to specify what data to copy, so clearly it gives said user a blank slate. > Switch to full-set bitmap by > default. This way we will not care about setting dirty bitmap in > copy-before-write filter when publish it so that it can be used in > separate of backup job. That’s a valid reason, though, so: Reviewed-by: Max Reitz Still, I find it stranger this way, because I’m more used to “initialization to 0 by default”. > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > block/backup.c | 16 +++++++--------- > block/block-copy.c | 1 + > 2 files changed, 8 insertions(+), 9 deletions(-) > > diff --git a/block/backup.c b/block/backup.c > index 90cca1ca30..706c54fea1 100644 > --- a/block/backup.c > +++ b/block/backup.c > @@ -233,18 +233,16 @@ static void backup_init_bcs_bitmap(BackupBlockJob *job) > BdrvDirtyBitmap *bcs_bitmap = block_copy_dirty_bitmap(job->bcs); > > if (job->sync_mode == MIRROR_SYNC_MODE_BITMAP) { > + bdrv_clear_dirty_bitmap(bcs_bitmap, NULL); > ret = bdrv_dirty_bitmap_merge_internal(bcs_bitmap, job->sync_bitmap, > NULL, true); > assert(ret); > - } else { > - if (job->sync_mode == MIRROR_SYNC_MODE_TOP) { > - /* > - * We can't hog the coroutine to initialize this thoroughly. > - * Set a flag and resume work when we are able to yield safely. > - */ > - block_copy_set_skip_unallocated(job->bcs, true); > - } > - bdrv_set_dirty_bitmap(bcs_bitmap, 0, job->len); > + } else if (job->sync_mode == MIRROR_SYNC_MODE_TOP) { > + /* > + * We can't hog the coroutine to initialize this thoroughly. > + * Set a flag and resume work when we are able to yield safely. > + */ > + block_copy_set_skip_unallocated(job->bcs, true); > } > > estimate = bdrv_get_dirty_count(bcs_bitmap); > diff --git a/block/block-copy.c b/block/block-copy.c > index 9020234c6e..4126f7e8cc 100644 > --- a/block/block-copy.c > +++ b/block/block-copy.c > @@ -296,6 +296,7 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target, > return NULL; > } > bdrv_disable_dirty_bitmap(copy_bitmap); > + bdrv_set_dirty_bitmap(copy_bitmap, 0, bdrv_dirty_bitmap_size(copy_bitmap)); > > /* > * Why we always set BDRV_REQ_SERIALISING write flag: >