From 02affd41b1157c511ea7fd0cc0bc61a07d9696b1 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Wed, 2 May 2018 18:47:36 +0800 Subject: [PATCH] qmp/migration: new command migrate-recover The first allow-oob=true command. It's used on destination side when the postcopy migration is paused and ready for a recovery. After execution, a new migration channel will be established for postcopy to continue. Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Peter Xu Message-Id: <20180502104740.12123-21-peterx@redhat.com> Signed-off-by: Juan Quintela --- s/2.12/2.13/ --- migration/migration.c | 24 ++++++++++++++++++++++++ migration/migration.h | 1 + migration/savevm.c | 3 +++ qapi/migration.json | 20 ++++++++++++++++++++ 4 files changed, 48 insertions(+) diff --git a/migration/migration.c b/migration/migration.c index c1832b0263..1beb5e07fb 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -1475,6 +1475,30 @@ void qmp_migrate_incoming(const char *uri, Error **errp) once = false; } +void qmp_migrate_recover(const char *uri, Error **errp) +{ + MigrationIncomingState *mis = migration_incoming_get_current(); + + if (mis->state != MIGRATION_STATUS_POSTCOPY_PAUSED) { + error_setg(errp, "Migrate recover can only be run " + "when postcopy is paused."); + return; + } + + if (atomic_cmpxchg(&mis->postcopy_recover_triggered, + false, true) == true) { + error_setg(errp, "Migrate recovery is triggered already"); + return; + } + + /* + * Note that this call will never start a real migration; it will + * only re-setup the migration stream and poke existing migration + * to continue using that newly established channel. + */ + qemu_start_incoming_migration(uri, errp); +} + bool migration_is_blocked(Error **errp) { if (qemu_savevm_state_blocked(errp)) { diff --git a/migration/migration.h b/migration/migration.h index b4438ccb65..f83f1064b5 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -77,6 +77,7 @@ struct MigrationIncomingState { struct PostcopyBlocktimeContext *blocktime_ctx; /* notify PAUSED postcopy incoming migrations to try to continue */ + bool postcopy_recover_triggered; QemuSemaphore postcopy_pause_sem_dst; QemuSemaphore postcopy_pause_sem_fault; }; diff --git a/migration/savevm.c b/migration/savevm.c index 8e7653badc..4251125831 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -2190,6 +2190,9 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis) { trace_postcopy_pause_incoming(); + /* Clear the triggered bit to allow one recovery */ + mis->postcopy_recover_triggered = false; + migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, MIGRATION_STATUS_POSTCOPY_PAUSED); diff --git a/qapi/migration.json b/qapi/migration.json index 4e8e61ceef..da351d7421 100644 --- a/qapi/migration.json +++ b/qapi/migration.json @@ -1191,3 +1191,23 @@ # Since: 2.9 ## { 'command': 'xen-colo-do-checkpoint' } + +## +# @migrate-recover: +# +# Provide a recovery migration stream URI. +# +# @uri: the URI to be used for the recovery of migration stream. +# +# Returns: nothing. +# +# Example: +# +# -> { "execute": "migrate-recover", +# "arguments": { "uri": "tcp:192.168.1.200:12345" } } +# <- { "return": {} } +# +# Since: 2.13 +## +{ 'command': 'migrate-recover', 'data': { 'uri': 'str' }, + 'allow-oob': true }