From patchwork Fri Aug 4 09:30:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Wang, Wei W" X-Patchwork-Id: 13341576 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 CB4C7C001DF for ; Fri, 4 Aug 2023 09:31:53 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qRr9Q-0004Fz-QF; Fri, 04 Aug 2023 05:31:16 -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 1qRr9J-0004Fo-3u for qemu-devel@nongnu.org; Fri, 04 Aug 2023 05:31:09 -0400 Received: from mgamail.intel.com ([192.55.52.93]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qRr9D-00061C-AG for qemu-devel@nongnu.org; Fri, 04 Aug 2023 05:31:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1691141463; x=1722677463; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=cKTpz5Tdbw6w2Gchfvbbj8ujbALk1nwwa7KAH13Ts/I=; b=brQDUxr9xQZt7VzRQEoRuSMVX01TClcUCF7ux3+P0xhYTPDHszKeaeSY 2tqSddpf7KVSRjPmMEuemS1FY/pGWljL7JSiBoRneSHosQQ/8K1i+HZzr chl4Do0HnT46G8qdvdR6JoUvfSwFHl8xeBo6R9zqTfxOTiTZy6etGVkQd kOj2KMPVjOoMdjJ/ggY6pJAdkJnNPJntvo13iOmA02sfUd/zhvgp2oAGO 6pps2fYRjb7CnYxtZWwSpIm1Y+BiIJmEv9cfXhWzA3T0SlbJB4wxZOmTm rGxaYOj8BQteOr+HrfCfSD2kXrAAljM00RIo0nPE3GgyyKYy9wqnbZR4H g==; X-IronPort-AV: E=McAfee;i="6600,9927,10791"; a="367573115" X-IronPort-AV: E=Sophos;i="6.01,254,1684825200"; d="scan'208";a="367573115" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Aug 2023 02:30:58 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10791"; a="903836927" X-IronPort-AV: E=Sophos;i="6.01,254,1684825200"; d="scan'208";a="903836927" Received: from tdx-lm.sh.intel.com ([10.239.53.27]) by orsmga005.jf.intel.com with ESMTP; 04 Aug 2023 02:30:56 -0700 From: Wei Wang To: peterx@redhat.com, quintela@redhat.com, isaku.yamahata@gmail.com Cc: qemu-devel@nongnu.org, Wei Wang Subject: [PATCH v2] migration: refactor migration_completion Date: Fri, 4 Aug 2023 17:30:53 +0800 Message-Id: <20230804093053.5037-1-wei.w.wang@intel.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Received-SPF: pass client-ip=192.55.52.93; envelope-from=wei.w.wang@intel.com; helo=mgamail.intel.com X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Current migration_completion function is a bit long. Refactor the long implementation into different subfunctions: - migration_completion_precopy: completion code related to precopy - migration_completion_postcopy: completion code related to postcopy - close_return_path_on_source: rp thread related cleanup on migration completion. It is named to match with open_return_path_on_source. This improves readability and is easier for future updates (e.g. add new subfunctions when completion code related to new features are needed). No functional changes intended. Signed-off-by: Wei Wang Reviewed-by: Peter Xu Reviewed-by: Isaku Yamahata Reviewed-by: Juan Quintela --- Changelog: - Merge await_return_path_close_on_source into close_return_path_on_source as the later basically just calls the previous; - make migration_completion_postcopy "void" as it doesn't return a value. migration/migration.c | 174 ++++++++++++++++++++++++------------------ 1 file changed, 98 insertions(+), 76 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index 5528acb65e..f1c55d1148 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -2048,9 +2048,13 @@ static int open_return_path_on_source(MigrationState *ms, return 0; } -/* Returns 0 if the RP was ok, otherwise there was an error on the RP */ -static int await_return_path_close_on_source(MigrationState *ms) +static int close_return_path_on_source(MigrationState *ms) { + if (!ms->rp_state.rp_thread_created) { + return 0; + } + trace_migration_return_path_end_before(); + /* * If this is a normal exit then the destination will send a SHUT and the * rp_thread will exit, however if there's an error we need to cause @@ -2068,6 +2072,8 @@ static int await_return_path_close_on_source(MigrationState *ms) qemu_thread_join(&ms->rp_state.rp_thread); ms->rp_state.rp_thread_created = false; trace_await_return_path_close_on_source_close(); + + trace_migration_return_path_end_after(ms->rp_state.error); return ms->rp_state.error; } @@ -2301,66 +2307,107 @@ static int migration_maybe_pause(MigrationState *s, return s->state == new_state ? 0 : -EINVAL; } -/** - * migration_completion: Used by migration_thread when there's not much left. - * The caller 'breaks' the loop when this returns. - * - * @s: Current migration state - */ -static void migration_completion(MigrationState *s) +static int migration_completion_precopy(MigrationState *s, + int *current_active_state) { int ret; - int current_active_state = s->state; - if (s->state == MIGRATION_STATUS_ACTIVE) { - qemu_mutex_lock_iothread(); - s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); - qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL); + qemu_mutex_lock_iothread(); + s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL); - s->vm_old_state = runstate_get(); - global_state_store(); + s->vm_old_state = runstate_get(); + global_state_store(); - ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); - trace_migration_completion_vm_stop(ret); - if (ret >= 0) { - ret = migration_maybe_pause(s, ¤t_active_state, - MIGRATION_STATUS_DEVICE); - } - if (ret >= 0) { - /* - * Inactivate disks except in COLO, and track that we - * have done so in order to remember to reactivate - * them if migration fails or is cancelled. - */ - s->block_inactive = !migrate_colo(); - migration_rate_set(RATE_LIMIT_DISABLED); - ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false, - s->block_inactive); - } + ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); + trace_migration_completion_vm_stop(ret); + if (ret < 0) { + goto out_unlock; + } - qemu_mutex_unlock_iothread(); + ret = migration_maybe_pause(s, current_active_state, + MIGRATION_STATUS_DEVICE); + if (ret < 0) { + goto out_unlock; + } - if (ret < 0) { - goto fail; - } - } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) { - trace_migration_completion_postcopy_end(); + /* + * Inactivate disks except in COLO, and track that we have done so in order + * to remember to reactivate them if migration fails or is cancelled. + */ + s->block_inactive = !migrate_colo(); + migration_rate_set(RATE_LIMIT_DISABLED); + ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false, + s->block_inactive); +out_unlock: + qemu_mutex_unlock_iothread(); + return ret; +} - qemu_mutex_lock_iothread(); - qemu_savevm_state_complete_postcopy(s->to_dst_file); - qemu_mutex_unlock_iothread(); +static void migration_completion_postcopy(MigrationState *s) +{ + trace_migration_completion_postcopy_end(); + qemu_mutex_lock_iothread(); + qemu_savevm_state_complete_postcopy(s->to_dst_file); + qemu_mutex_unlock_iothread(); + + /* + * Shutdown the postcopy fast path thread. This is only needed when dest + * QEMU binary is old (7.1/7.2). QEMU 8.0+ doesn't need this. + */ + if (migrate_postcopy_preempt() && s->preempt_pre_7_2) { + postcopy_preempt_shutdown_file(s); + } + + trace_migration_completion_postcopy_end_after_complete(); +} + +static void migration_completion_failed(MigrationState *s, + int current_active_state) +{ + if (s->block_inactive && (s->state == MIGRATION_STATUS_ACTIVE || + s->state == MIGRATION_STATUS_DEVICE)) { /* - * Shutdown the postcopy fast path thread. This is only needed - * when dest QEMU binary is old (7.1/7.2). QEMU 8.0+ doesn't need - * this. + * If not doing postcopy, vm_start() will be called: let's + * regain control on images. */ - if (migrate_postcopy_preempt() && s->preempt_pre_7_2) { - postcopy_preempt_shutdown_file(s); + Error *local_err = NULL; + + qemu_mutex_lock_iothread(); + bdrv_activate_all(&local_err); + if (local_err) { + error_report_err(local_err); + } else { + s->block_inactive = false; } + qemu_mutex_unlock_iothread(); + } - trace_migration_completion_postcopy_end_after_complete(); + migrate_set_state(&s->state, current_active_state, + MIGRATION_STATUS_FAILED); +} + +/** + * migration_completion: Used by migration_thread when there's not much left. + * The caller 'breaks' the loop when this returns. + * + * @s: Current migration state + */ +static void migration_completion(MigrationState *s) +{ + int ret = 0; + int current_active_state = s->state; + + if (s->state == MIGRATION_STATUS_ACTIVE) { + ret = migration_completion_precopy(s, ¤t_active_state); + } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) { + migration_completion_postcopy(s); } else { + ret = -1; + } + + if (ret < 0) { goto fail; } @@ -2370,14 +2417,8 @@ static void migration_completion(MigrationState *s) * it will wait for the destination to send it's status in * a SHUT command). */ - if (s->rp_state.rp_thread_created) { - int rp_error; - trace_migration_return_path_end_before(); - rp_error = await_return_path_close_on_source(s); - trace_migration_return_path_end_after(rp_error); - if (rp_error) { - goto fail; - } + if (close_return_path_on_source(s) < 0) { + goto fail; } if (qemu_file_get_error(s->to_dst_file)) { @@ -2397,26 +2438,7 @@ static void migration_completion(MigrationState *s) return; fail: - if (s->block_inactive && (s->state == MIGRATION_STATUS_ACTIVE || - s->state == MIGRATION_STATUS_DEVICE)) { - /* - * If not doing postcopy, vm_start() will be called: let's - * regain control on images. - */ - Error *local_err = NULL; - - qemu_mutex_lock_iothread(); - bdrv_activate_all(&local_err); - if (local_err) { - error_report_err(local_err); - } else { - s->block_inactive = false; - } - qemu_mutex_unlock_iothread(); - } - - migrate_set_state(&s->state, current_active_state, - MIGRATION_STATUS_FAILED); + migration_completion_failed(s, current_active_state); } /**