[{"id":1773416,"web_url":"http://patchwork.ozlabs.org/comment/1773416/","msgid":"<20170922095617.GB2620@work-vm>","list_archive_url":null,"date":"2017-09-22T09:56:18","subject":"Re: [Qemu-devel] [RFC v2 16/33] migration: rebuild channel on source","submitter":{"id":48102,"url":"http://patchwork.ozlabs.org/api/people/48102/","name":"Dr. David Alan Gilbert","email":"dgilbert@redhat.com"},"content":"* Peter Xu (peterx@redhat.com) wrote:\n> This patch detects the \"resume\" flag of migration command, rebuild the\n> channels only if the flag is set.\n> \n> Signed-off-by: Peter Xu \n\nReviewed-by: Dr. David Alan Gilbert \n\n> ---\n> migration/migration.c | 92 ++++++++++++++++++++++++++++++++++++++-------------\n> 1 file changed, 69 insertions(+), 23 deletions(-)\n> \n> diff --git a/migration/migration.c b/migration/migration.c\n> index 15b8eb1..deb947b 100644\n> --- a/migration/migration.c\n> +++ b/migration/migration.c\n> @@ -1233,49 +1233,75 @@ bool migration_is_blocked(Error **errp)\n> return false;\n> }\n> \n> -void qmp_migrate(const char *uri, bool has_blk, bool blk,\n> - bool has_inc, bool inc, bool has_detach, bool detach,\n> - bool has_resume, bool resume, Error **errp)\n> +/* Returns true if continue to migrate, or false if error detected */\n> +static bool migrate_prepare(MigrationState *s, bool blk, bool blk_inc,\n> + bool resume, Error **errp)\n> {\n> Error *local_err = NULL;\n> - MigrationState *s = migrate_get_current();\n> - const char *p;\n> +\n> + if (resume) {\n> + if (s->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {\n> + error_setg(errp, \"Cannot resume if there is no \"\n> + \"paused migration\");\n> + return false;\n> + }\n> + /* This is a resume, skip init status */\n> + return true;\n> + }\n> \n> if (migration_is_setup_or_active(s->state) ||\n> s->state == MIGRATION_STATUS_CANCELLING ||\n> s->state == MIGRATION_STATUS_COLO) {\n> error_setg(errp, QERR_MIGRATION_ACTIVE);\n> - return;\n> + return false;\n> }\n> +\n> if (runstate_check(RUN_STATE_INMIGRATE)) {\n> error_setg(errp, \"Guest is waiting for an incoming migration\");\n> - return;\n> + return false;\n> }\n> \n> if (migration_is_blocked(errp)) {\n> - return;\n> + return false;\n> }\n> \n> - if ((has_blk && blk) || (has_inc && inc)) {\n> + if (blk || blk_inc) {\n> if (migrate_use_block() || migrate_use_block_incremental()) {\n> error_setg(errp, \"Command options are incompatible with \"\n> \"current migration capabilities\");\n> - return;\n> + return false;\n> }\n> migrate_set_block_enabled(true, &local_err);\n> if (local_err) {\n> error_propagate(errp, local_err);\n> - return;\n> + return false;\n> }\n> s->must_remove_block_options = true;\n> }\n> \n> - if (has_inc && inc) {\n> + if (blk_inc) {\n> migrate_set_block_incremental(s, true);\n> }\n> \n> migrate_init(s);\n> \n> + return true;\n> +}\n> +\n> +void qmp_migrate(const char *uri, bool has_blk, bool blk,\n> + bool has_inc, bool inc, bool has_detach, bool detach,\n> + bool has_resume, bool resume, Error **errp)\n> +{\n> + Error *local_err = NULL;\n> + MigrationState *s = migrate_get_current();\n> + const char *p;\n> +\n> + if (!migrate_prepare(s, has_blk && blk, has_inc && inc,\n> + has_resume && resume, errp)) {\n> + /* Error detected, put into errp */\n> + return;\n> + }\n> +\n> if (strstart(uri, \"tcp:\", &p)) {\n> tcp_start_outgoing_migration(s, p, &local_err);\n> #ifdef CONFIG_RDMA\n> @@ -1697,7 +1723,8 @@ out:\n> return NULL;\n> }\n> \n> -static int open_return_path_on_source(MigrationState *ms)\n> +static int open_return_path_on_source(MigrationState *ms,\n> + bool create_thread)\n> {\n> \n> ms->rp_state.from_dst_file = qemu_file_get_return_path(ms->to_dst_file);\n> @@ -1706,6 +1733,12 @@ static int open_return_path_on_source(MigrationState *ms)\n> }\n> \n> trace_open_return_path_on_source();\n> +\n> + if (!create_thread) {\n> + /* We're done */\n> + return 0;\n> + }\n> +\n> qemu_thread_create(&ms->rp_state.rp_thread, \"return path\",\n> source_return_path_thread, ms, QEMU_THREAD_JOINABLE);\n> \n> @@ -2263,15 +2296,24 @@ static void *migration_thread(void *opaque)\n> \n> void migrate_fd_connect(MigrationState *s)\n> {\n> - s->expected_downtime = s->parameters.downtime_limit;\n> - s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s);\n> + int64_t rate_limit;\n> + bool resume = s->state == MIGRATION_STATUS_POSTCOPY_PAUSED;\n> \n> - qemu_file_set_blocking(s->to_dst_file, true);\n> - qemu_file_set_rate_limit(s->to_dst_file,\n> - s->parameters.max_bandwidth / XFER_LIMIT_RATIO);\n> + if (resume) {\n> + /* This is a resumed migration */\n> + rate_limit = INT64_MAX;\n> + } else {\n> + /* This is a fresh new migration */\n> + rate_limit = s->parameters.max_bandwidth / XFER_LIMIT_RATIO;\n> + s->expected_downtime = s->parameters.downtime_limit;\n> + s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s);\n> \n> - /* Notify before starting migration thread */\n> - notifier_list_notify(&migration_state_notifiers, s);\n> + /* Notify before starting migration thread */\n> + notifier_list_notify(&migration_state_notifiers, s);\n> + }\n> +\n> + qemu_file_set_rate_limit(s->to_dst_file, rate_limit);\n> + qemu_file_set_blocking(s->to_dst_file, true);\n> \n> /*\n> * Open the return path. For postcopy, it is used exclusively. For\n> @@ -2279,15 +2321,19 @@ void migrate_fd_connect(MigrationState *s)\n> * QEMU uses the return path.\n> */\n> if (migrate_postcopy_ram() || migrate_use_return_path()) {\n> - if (open_return_path_on_source(s)) {\n> + if (open_return_path_on_source(s, !resume)) {\n> error_report(\"Unable to open return-path for postcopy\");\n> - migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,\n> - MIGRATION_STATUS_FAILED);\n> + migrate_set_state(&s->state, s->state, MIGRATION_STATUS_FAILED);\n> migrate_fd_cleanup(s);\n> return;\n> }\n> }\n> \n> + if (resume) {\n> + /* TODO: do the resume logic */\n> + return;\n> + }\n> +\n> qemu_thread_create(&s->thread, \"live_migration\", migration_thread, s,\n> QEMU_THREAD_JOINABLE);\n> s->migration_thread_running = true;\n> -- \n> 2.7.4\n> \n> \n--\nDr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ext-mx02.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com","ext-mx02.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=dgilbert@redhat.com"],"Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xz85c0yRJz9s9Y\n\tfor ;\n\tFri, 22 Sep 2017 19:56:51 +1000 (AEST)","from localhost ([::1]:57657 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dvKhU-0006ve-R9\n\tfor incoming@patchwork.ozlabs.org; Fri, 22 Sep 2017 05:56:48 -0400","from eggs.gnu.org ([2001:4830:134:3::10]:44853)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from ) id 1dvKhC-0006vY-8r\n\tfor qemu-devel@nongnu.org; Fri, 22 Sep 2017 05:56:31 -0400","from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from ) id 1dvKh8-0006lH-4V\n\tfor qemu-devel@nongnu.org; Fri, 22 Sep 2017 05:56:30 -0400","from mx1.redhat.com ([209.132.183.28]:34464)\n\tby eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from ) id 1dvKh7-0006kq-R1\n\tfor qemu-devel@nongnu.org; Fri, 22 Sep 2017 05:56:26 -0400","from smtp.corp.redhat.com\n\t(int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14])\n\t(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby mx1.redhat.com (Postfix) with ESMTPS id 82BE4806B2;\n\tFri, 22 Sep 2017 09:56:24 +0000 (UTC)","from work-vm (ovpn-117-236.ams2.redhat.com [10.36.117.236])\n\tby smtp.corp.redhat.com (Postfix) with ESMTPS id 817055D9CC;\n\tFri, 22 Sep 2017 09:56:20 +0000 (UTC)"],"DMARC-Filter":"OpenDMARC Filter v1.3.2 mx1.redhat.com 82BE4806B2","Date":"Fri, 22 Sep 2017 10:56:18 +0100","From":"\"Dr. David Alan Gilbert\" ","To":"Peter Xu ","Message-ID":"<20170922095617.GB2620@work-vm>","References":"<1504081950-2528-1-git-send-email-peterx@redhat.com>\n\t<1504081950-2528-17-git-send-email-peterx@redhat.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"<1504081950-2528-17-git-send-email-peterx@redhat.com>","User-Agent":"Mutt/1.8.3 (2017-05-23)","X-Scanned-By":"MIMEDefang 2.79 on 10.5.11.14","X-Greylist":"Sender IP whitelisted, not delayed by milter-greylist-4.5.16\n\t(mx1.redhat.com [10.5.110.26]);\n\tFri, 22 Sep 2017 09:56:24 +0000 (UTC)","X-detected-operating-system":"by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic]\n\t[fuzzy]","X-Received-From":"209.132.183.28","Subject":"Re: [Qemu-devel] [RFC v2 16/33] migration: rebuild channel on source","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Cc":"Laurent Vivier ,\n\tAndrea Arcangeli , \n\tJuan Quintela , qemu-devel@nongnu.org,\n\tAlexey Perevalov ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"}}]