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GET /api/patches/807507/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 807507,
    "url": "http://patchwork.ozlabs.org/api/patches/807507/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/patch/1504081950-2528-17-git-send-email-peterx@redhat.com/",
    "project": {
        "id": 14,
        "url": "http://patchwork.ozlabs.org/api/projects/14/?format=api",
        "name": "QEMU Development",
        "link_name": "qemu-devel",
        "list_id": "qemu-devel.nongnu.org",
        "list_email": "qemu-devel@nongnu.org",
        "web_url": "",
        "scm_url": "",
        "webscm_url": "",
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<1504081950-2528-17-git-send-email-peterx@redhat.com>",
    "list_archive_url": null,
    "date": "2017-08-30T08:32:13",
    "name": "[RFC,v2,16/33] migration: rebuild channel on source",
    "commit_ref": null,
    "pull_url": null,
    "state": "new",
    "archived": false,
    "hash": "d3abc91ba9c658c603454621b56f77323cc1e3e8",
    "submitter": {
        "id": 67717,
        "url": "http://patchwork.ozlabs.org/api/people/67717/?format=api",
        "name": "Peter Xu",
        "email": "peterx@redhat.com"
    },
    "delegate": null,
    "mbox": "http://patchwork.ozlabs.org/project/qemu-devel/patch/1504081950-2528-17-git-send-email-peterx@redhat.com/mbox/",
    "series": [
        {
            "id": 552,
            "url": "http://patchwork.ozlabs.org/api/series/552/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/list/?series=552",
            "date": "2017-08-30T08:31:59",
            "name": "Migration: postcopy failure recovery",
            "version": 2,
            "mbox": "http://patchwork.ozlabs.org/series/552/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/807507/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/807507/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>",
        "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=<UNKNOWN>)",
            "ext-mx05.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com",
            "ext-mx05.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=peterx@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 3xhzgW663Gz9t2Q\n\tfor <incoming@patchwork.ozlabs.org>;\n\tWed, 30 Aug 2017 18:48:39 +1000 (AEST)",
            "from localhost ([::1]:49081 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>)\n\tid 1dmyft-0003Jp-03\n\tfor incoming@patchwork.ozlabs.org; Wed, 30 Aug 2017 04:48:37 -0400",
            "from eggs.gnu.org ([2001:4830:134:3::10]:34446)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from <peterx@redhat.com>) id 1dmyRm-0007lM-9n\n\tfor qemu-devel@nongnu.org; Wed, 30 Aug 2017 04:34:03 -0400",
            "from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from <peterx@redhat.com>) id 1dmyRh-0003Yb-AB\n\tfor qemu-devel@nongnu.org; Wed, 30 Aug 2017 04:34:02 -0400",
            "from mx1.redhat.com ([209.132.183.28]:49664)\n\tby eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from <peterx@redhat.com>) id 1dmyRh-0003YG-1H\n\tfor qemu-devel@nongnu.org; Wed, 30 Aug 2017 04:33:57 -0400",
            "from smtp.corp.redhat.com\n\t(int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15])\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 07533A711;\n\tWed, 30 Aug 2017 08:33:56 +0000 (UTC)",
            "from pxdev.xzpeter.org.com (dhcp-14-103.nay.redhat.com\n\t[10.66.14.103])\n\tby smtp.corp.redhat.com (Postfix) with ESMTP id AFD94871ED;\n\tWed, 30 Aug 2017 08:33:43 +0000 (UTC)"
        ],
        "DMARC-Filter": "OpenDMARC Filter v1.3.2 mx1.redhat.com 07533A711",
        "From": "Peter Xu <peterx@redhat.com>",
        "To": "qemu-devel@nongnu.org",
        "Date": "Wed, 30 Aug 2017 16:32:13 +0800",
        "Message-Id": "<1504081950-2528-17-git-send-email-peterx@redhat.com>",
        "In-Reply-To": "<1504081950-2528-1-git-send-email-peterx@redhat.com>",
        "References": "<1504081950-2528-1-git-send-email-peterx@redhat.com>",
        "X-Scanned-By": "MIMEDefang 2.79 on 10.5.11.15",
        "X-Greylist": "Sender IP whitelisted, not delayed by milter-greylist-4.5.16\n\t(mx1.redhat.com [10.5.110.29]);\n\tWed, 30 Aug 2017 08:33:56 +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": "[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": "<qemu-devel.nongnu.org>",
        "List-Unsubscribe": "<https://lists.nongnu.org/mailman/options/qemu-devel>,\n\t<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>",
        "List-Archive": "<http://lists.nongnu.org/archive/html/qemu-devel/>",
        "List-Post": "<mailto:qemu-devel@nongnu.org>",
        "List-Help": "<mailto:qemu-devel-request@nongnu.org?subject=help>",
        "List-Subscribe": "<https://lists.nongnu.org/mailman/listinfo/qemu-devel>,\n\t<mailto:qemu-devel-request@nongnu.org?subject=subscribe>",
        "Cc": "Laurent Vivier <lvivier@redhat.com>,\n\tAndrea Arcangeli <aarcange@redhat.com>, \n\tJuan Quintela <quintela@redhat.com>,\n\tAlexey Perevalov <a.perevalov@samsung.com>, peterx@redhat.com,\n\t\"Dr . David Alan Gilbert\" <dgilbert@redhat.com>",
        "Errors-To": "qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org",
        "Sender": "\"Qemu-devel\"\n\t<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>"
    },
    "content": "This patch detects the \"resume\" flag of migration command, rebuild the\nchannels only if the flag is set.\n\nSigned-off-by: Peter Xu <peterx@redhat.com>\n---\n migration/migration.c | 92 ++++++++++++++++++++++++++++++++++++++-------------\n 1 file changed, 69 insertions(+), 23 deletions(-)",
    "diff": "diff --git a/migration/migration.c b/migration/migration.c\nindex 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",
    "prefixes": [
        "RFC",
        "v2",
        "16/33"
    ]
}