From 1a8e44a89f1976e06300393337f78d561f95b339 Mon Sep 17 00:00:00 2001 From: Andrey Gruzdev Date: Thu, 1 Apr 2021 12:22:24 +0300 Subject: [PATCH] migration: Inhibit virtio-balloon for the duration of background snapshot The same thing as for incoming postcopy - we cannot deal with concurrent RAM discards when using background snapshot feature in outgoing migration. Fixes: 8518278a6af589ccc401f06e35f171b1e6fae800 (migration: implementation of background snapshot thread) Signed-off-by: Andrey Gruzdev Reported-by: David Hildenbrand Reviewed-by: David Hildenbrand Message-Id: <20210401092226.102804-3-andrey.gruzdev@virtuozzo.com> Signed-off-by: Dr. David Alan Gilbert --- hw/virtio/virtio-balloon.c | 8 ++++++-- include/migration/misc.h | 2 ++ migration/migration.c | 8 ++++++++ 3 files changed, 16 insertions(+), 2 deletions(-) diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index e770955176..d120bf8f43 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -66,8 +66,12 @@ static bool virtio_balloon_pbp_matches(PartiallyBalloonedPage *pbp, static bool virtio_balloon_inhibited(void) { - /* Postcopy cannot deal with concurrent discards, so it's special. */ - return ram_block_discard_is_disabled() || migration_in_incoming_postcopy(); + /* + * Postcopy cannot deal with concurrent discards, + * so it's special, as well as background snapshots. + */ + return ram_block_discard_is_disabled() || migration_in_incoming_postcopy() || + migration_in_bg_snapshot(); } static void balloon_inflate_page(VirtIOBalloon *balloon, diff --git a/include/migration/misc.h b/include/migration/misc.h index bccc1b6b44..738675ef52 100644 --- a/include/migration/misc.h +++ b/include/migration/misc.h @@ -70,6 +70,8 @@ bool migration_in_postcopy_after_devices(MigrationState *); void migration_global_dump(Monitor *mon); /* True if incomming migration entered POSTCOPY_INCOMING_DISCARD */ bool migration_in_incoming_postcopy(void); +/* True if background snapshot is active */ +bool migration_in_bg_snapshot(void); /* migration/block-dirty-bitmap.c */ void dirty_bitmap_mig_init(void); diff --git a/migration/migration.c b/migration/migration.c index 00e13f9d58..be4729e7c8 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -1976,6 +1976,14 @@ bool migration_in_incoming_postcopy(void) return ps >= POSTCOPY_INCOMING_DISCARD && ps < POSTCOPY_INCOMING_END; } +bool migration_in_bg_snapshot(void) +{ + MigrationState *s = migrate_get_current(); + + return migrate_background_snapshot() && + migration_is_setup_or_active(s->state); +} + bool migration_is_idle(void) { MigrationState *s = current_migration;