From dd42ce24a3cda4be3c839aceb91fdf85e31c194f Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Mon, 15 May 2023 16:06:39 +0300 Subject: migration: split migration_incoming_co Originally, migration_incoming_co was introduced by 25d0c16f625feb3b6 "migration: Switch to COLO process after finishing loadvm" to be able to enter from COLO code to one specific yield point, added by 25d0c16f625feb3b6. Later in 923709896b1b0 "migration: poll the cm event for destination qemu" we reused this variable to wake the migration incoming coroutine from RDMA code. That was doubtful idea. Entering coroutines is a very fragile thing: you should be absolutely sure which yield point you are going to enter. I don't know how much is it safe to enter during qemu_loadvm_state() which I think what RDMA want to do. But for sure RDMA shouldn't enter the special COLO-related yield-point. As well, COLO code doesn't want to enter during qemu_loadvm_state(), it want to enter it's own specific yield-point. As well, when in 8e48ac95865ac97d "COLO: Add block replication into colo process" we added bdrv_invalidate_cache_all() call (now it's called activate_all()) it became possible to enter the migration incoming coroutine during that call which is wrong too. So, let't make these things separate and disjoint: loadvm_co for RDMA, non-NULL during qemu_loadvm_state(), and colo_incoming_co for COLO, non-NULL only around specific yield. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Juan Quintela Message-Id: <20230515130640.46035-3-vsementsov@yandex-team.ru> Signed-off-by: Juan Quintela --- migration/migration.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'migration/migration.h') diff --git a/migration/migration.h b/migration/migration.h index 7721c76..48a4612 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -162,8 +162,15 @@ struct MigrationIncomingState { int state; + /* + * The incoming migration coroutine, non-NULL during qemu_loadvm_state(). + * Used to wake the migration incoming coroutine from rdma code. How much is + * it safe - it's a question. + */ + Coroutine *loadvm_co; + /* The coroutine we should enter (back) after failover */ - Coroutine *migration_incoming_co; + Coroutine *colo_incoming_co; QemuSemaphore colo_incoming_sem; /* -- cgit v1.1