migration: add trace point when vm_stop_force_state fails

This is a critical failure scenario for migration that is hard to
diagnose from existing probes. Most likely it is caused by an error
from bdrv_flush(), but we're not logging the errno anywhere, hence
this new probe.

Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2021-04-15 14:33:51 +01:00
parent 213de8a2fb
commit 626ff6515d
2 changed files with 2 additions and 0 deletions

View File

@ -3115,6 +3115,7 @@ static void migration_completion(MigrationState *s)
if (!ret) {
bool inactivate = !migrate_colo_enabled();
ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
trace_migration_completion_vm_stop(ret);
if (ret >= 0) {
ret = migration_maybe_pause(s, &current_active_state,
MIGRATION_STATUS_DEVICE);

View File

@ -149,6 +149,7 @@ migrate_pending(uint64_t size, uint64_t max, uint64_t pre, uint64_t compat, uint
migrate_send_rp_message(int msg_type, uint16_t len) "%d: len %d"
migrate_send_rp_recv_bitmap(char *name, int64_t size) "block '%s' size 0x%"PRIi64
migration_completion_file_err(void) ""
migration_completion_vm_stop(int ret) "ret %d"
migration_completion_postcopy_end(void) ""
migration_completion_postcopy_end_after_complete(void) ""
migration_rate_limit_pre(int ms) "%d ms"