From 29ae8a4133082e16970c9d4be09f4b6a15034617 Mon Sep 17 00:00:00 2001 From: "Michael R. Hines" Date: Mon, 22 Jul 2013 10:01:57 -0400 Subject: [PATCH] rdma: introduce MIG_STATE_NONE and change MIG_STATE_SETUP state transition As described in the previous patch, until now, the MIG_STATE_SETUP state was not really a 'formal' state. It has been used as a 'zero' state (what we're calling 'NONE' here) and QEMU has been unconditionally transitioning into this state when the QMP migration command was called. Instead we want to introduce MIG_STATE_NONE, which is our starting state in the state machine, and then immediately transition into the MIG_STATE_SETUP state when the QMP migrate command is issued. In order to do this, we must delay the transition into MIG_STATE_ACTIVE until later in the migration_thread(). This is done to be able to timestamp the amount of time spent in the SETUP state for proper accounting to the user during an RDMA migration. Furthermore, the management software, until now, has never been aware of the existence of the SETUP state whatsoever. This must change, because, timing of this state implies that the state actually exists. These two patches cannot be separated because the 'query_migrate' QMP switch statement needs to know how to handle this new state transition. Reviewed-by: Juan Quintela Tested-by: Michael R. Hines Signed-off-by: Michael R. Hines Signed-off-by: Juan Quintela --- migration.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/migration.c b/migration.c index fcdcf6196a..636f7dbf6f 100644 --- a/migration.c +++ b/migration.c @@ -36,7 +36,8 @@ #endif enum { - MIG_STATE_ERROR, + MIG_STATE_ERROR = -1, + MIG_STATE_NONE, MIG_STATE_SETUP, MIG_STATE_CANCELLED, MIG_STATE_ACTIVE, @@ -63,7 +64,7 @@ static NotifierList migration_state_notifiers = MigrationState *migrate_get_current(void) { static MigrationState current_migration = { - .state = MIG_STATE_SETUP, + .state = MIG_STATE_NONE, .bandwidth_limit = MAX_THROTTLE, .xbzrle_cache_size = DEFAULT_MIGRATE_CACHE_SIZE, .mbps = -1, @@ -184,9 +185,13 @@ MigrationInfo *qmp_query_migrate(Error **errp) MigrationState *s = migrate_get_current(); switch (s->state) { - case MIG_STATE_SETUP: + case MIG_STATE_NONE: /* no migration has happened ever */ break; + case MIG_STATE_SETUP: + info->has_status = true; + info->status = g_strdup("setup"); + break; case MIG_STATE_ACTIVE: info->has_status = true; info->status = g_strdup("active"); @@ -257,7 +262,7 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params, MigrationState *s = migrate_get_current(); MigrationCapabilityStatusList *cap; - if (s->state == MIG_STATE_ACTIVE) { + if (s->state == MIG_STATE_ACTIVE || s->state == MIG_STATE_SETUP) { error_set(errp, QERR_MIGRATION_ACTIVE); return; } @@ -392,7 +397,7 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk, params.blk = blk; params.shared = inc; - if (s->state == MIG_STATE_ACTIVE) { + if (s->state == MIG_STATE_ACTIVE || s->state == MIG_STATE_SETUP) { error_set(errp, QERR_MIGRATION_ACTIVE); return; } @@ -542,6 +547,8 @@ static void *migration_thread(void *opaque) DPRINTF("beginning savevm\n"); qemu_savevm_state_begin(s->file, &s->params); + migrate_set_state(s, MIG_STATE_SETUP, MIG_STATE_ACTIVE); + while (s->state == MIG_STATE_ACTIVE) { int64_t current_time; uint64_t pending_size; @@ -632,8 +639,8 @@ static void *migration_thread(void *opaque) void migrate_fd_connect(MigrationState *s) { - s->state = MIG_STATE_ACTIVE; - trace_migrate_set_state(MIG_STATE_ACTIVE); + s->state = MIG_STATE_SETUP; + trace_migrate_set_state(MIG_STATE_SETUP); /* This is a best 1st approximation. ns to ms */ s->expected_downtime = max_downtime/1000000;