From patchwork Fri Oct 13 09:21:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fiona Ebner X-Patchwork-Id: 13420590 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 B9075CDB483 for ; Fri, 13 Oct 2023 09:24:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qrEMr-0005tm-Ay; Fri, 13 Oct 2023 05:22:01 -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 1qrEMo-0005lj-Ho; Fri, 13 Oct 2023 05:21:58 -0400 Received: from proxmox-new.maurer-it.com ([94.136.29.106]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qrEMl-00072u-Lk; Fri, 13 Oct 2023 05:21:58 -0400 Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id E26FC48F32; Fri, 13 Oct 2023 11:21:51 +0200 (CEST) From: Fiona Ebner To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, armbru@redhat.com, eblake@redhat.com, hreitz@redhat.com, kwolf@redhat.com, vsementsov@yandex-team.ru, jsnow@redhat.com, den@virtuozzo.com, t.lamprecht@proxmox.com, alexander.ivanov@virtuozzo.com Subject: [PATCH v3 5/9] mirror: implement mirror_change method Date: Fri, 13 Oct 2023 11:21:39 +0200 Message-Id: <20231013092143.365296-6-f.ebner@proxmox.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231013092143.365296-1-f.ebner@proxmox.com> References: <20231013092143.365296-1-f.ebner@proxmox.com> MIME-Version: 1.0 Received-SPF: pass client-ip=94.136.29.106; envelope-from=f.ebner@proxmox.com; helo=proxmox-new.maurer-it.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, 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 which allows switching the @copy-mode from 'background' to 'write-blocking'. This is useful for management applications, so they can start out in background mode to avoid limiting guest write speed and switch to active mode when certain criteria are fulfilled. In presence of an iothread, the copy_mode member is now shared between the iothread and the main thread, so turn accesses to it atomic. Signed-off-by: Fiona Ebner --- Changes in v3: * turn accesses to copy_mode atomic and... * ...slightly adapt error handling in mirror_change as a consequence block/mirror.c | 33 ++++++++++++++++++++++++++++++--- qapi/block-core.json | 13 ++++++++++++- 2 files changed, 42 insertions(+), 4 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index 8992c09172..889cce5414 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -1075,7 +1075,7 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) */ job_transition_to_ready(&s->common.job); } - if (s->copy_mode != MIRROR_COPY_MODE_BACKGROUND) { + if (qatomic_read(&s->copy_mode) != MIRROR_COPY_MODE_BACKGROUND) { s->actively_synced = true; } @@ -1246,6 +1246,32 @@ static bool commit_active_cancel(Job *job, bool force) return force || !job_is_ready(job); } +static void mirror_change(BlockJob *job, BlockJobChangeOptions *opts, + Error **errp) +{ + MirrorBlockJob *s = container_of(job, MirrorBlockJob, common); + BlockJobChangeOptionsMirror *change_opts = &opts->u.mirror; + MirrorCopyMode current; + + if (qatomic_read(&s->copy_mode) == change_opts->copy_mode) { + return; + } + + if (change_opts->copy_mode != MIRROR_COPY_MODE_WRITE_BLOCKING) { + error_setg(errp, "Change to copy mode '%s' is not implemented", + MirrorCopyMode_str(change_opts->copy_mode)); + return; + } + + current = qatomic_cmpxchg(&s->copy_mode, MIRROR_COPY_MODE_BACKGROUND, + change_opts->copy_mode); + if (current != MIRROR_COPY_MODE_BACKGROUND) { + error_setg(errp, "Expected current copy mode '%s', got '%s'", + MirrorCopyMode_str(MIRROR_COPY_MODE_BACKGROUND), + MirrorCopyMode_str(current)); + } +} + static const BlockJobDriver mirror_job_driver = { .job_driver = { .instance_size = sizeof(MirrorBlockJob), @@ -1260,6 +1286,7 @@ static const BlockJobDriver mirror_job_driver = { .cancel = mirror_cancel, }, .drained_poll = mirror_drained_poll, + .change = mirror_change, }; static const BlockJobDriver commit_active_job_driver = { @@ -1467,7 +1494,7 @@ static bool should_copy_to_target(MirrorBDSOpaque *s) { return s->job && s->job->ret >= 0 && !job_is_cancelled(&s->job->common.job) && - s->job->copy_mode == MIRROR_COPY_MODE_WRITE_BLOCKING; + qatomic_read(&s->job->copy_mode) == MIRROR_COPY_MODE_WRITE_BLOCKING; } static int coroutine_fn GRAPH_RDLOCK @@ -1812,7 +1839,7 @@ static BlockJob *mirror_start_job( s->is_none_mode = is_none_mode; s->backing_mode = backing_mode; s->zero_target = zero_target; - s->copy_mode = copy_mode; + qatomic_set(&s->copy_mode, copy_mode); s->base = base; s->base_overlay = bdrv_find_overlay(bs, base); s->granularity = granularity; diff --git a/qapi/block-core.json b/qapi/block-core.json index c6f31a9399..01427c259a 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -3044,6 +3044,17 @@ { 'command': 'block-job-finalize', 'data': { 'id': 'str' }, 'allow-preconfig': true } +## +# @BlockJobChangeOptionsMirror: +# +# @copy-mode: Switch to this copy mode. Currenlty, only the switch +# from 'background' to 'write-blocking' is implemented. +# +# Since: 8.2 +## +{ 'struct': 'BlockJobChangeOptionsMirror', + 'data': { 'copy-mode' : 'MirrorCopyMode' } } + ## # @BlockJobChangeOptions: # @@ -3058,7 +3069,7 @@ { 'union': 'BlockJobChangeOptions', 'base': { 'id': 'str', 'type': 'JobType' }, 'discriminator': 'type', - 'data': {} } + 'data': { 'mirror': 'BlockJobChangeOptionsMirror' } } ## # @block-job-change: