aboutsummaryrefslogtreecommitdiff
path: root/migration
diff options
context:
space:
mode:
Diffstat (limited to 'migration')
-rw-r--r--migration/migration.c1
-rw-r--r--migration/migration.h3
-rw-r--r--migration/savevm.c63
-rw-r--r--migration/trace-events2
4 files changed, 67 insertions, 2 deletions
diff --git a/migration/migration.c b/migration/migration.c
index 8392cf467d..4a7c02fd3c 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -159,6 +159,7 @@ MigrationIncomingState *migration_incoming_get_current(void)
sizeof(struct PostCopyFD));
qemu_mutex_init(&mis_current.rp_mutex);
qemu_event_init(&mis_current.main_thread_load_event, false);
+ qemu_sem_init(&mis_current.postcopy_pause_sem_dst, 0);
init_dirty_bitmap_incoming_migration();
diff --git a/migration/migration.h b/migration/migration.h
index 60283c39b2..0ccdcb8ffe 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -73,6 +73,9 @@ struct MigrationIncomingState {
* live migration, to calculate vCPU block time
* */
struct PostcopyBlocktimeContext *blocktime_ctx;
+
+ /* notify PAUSED postcopy incoming migrations to try to continue */
+ QemuSemaphore postcopy_pause_sem_dst;
};
MigrationIncomingState *migration_incoming_get_current(void);
diff --git a/migration/savevm.c b/migration/savevm.c
index e2be02afe4..8ad99b1eaa 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1564,8 +1564,8 @@ static int loadvm_postcopy_ram_handle_discard(MigrationIncomingState *mis,
*/
static void *postcopy_ram_listen_thread(void *opaque)
{
- QEMUFile *f = opaque;
MigrationIncomingState *mis = migration_incoming_get_current();
+ QEMUFile *f = mis->from_src_file;
int load_res;
migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
@@ -1579,6 +1579,14 @@ static void *postcopy_ram_listen_thread(void *opaque)
*/
qemu_file_set_blocking(f, true);
load_res = qemu_loadvm_state_main(f, mis);
+
+ /*
+ * This is tricky, but, mis->from_src_file can change after it
+ * returns, when postcopy recovery happened. In the future, we may
+ * want a wrapper for the QEMUFile handle.
+ */
+ f = mis->from_src_file;
+
/* And non-blocking again so we don't block in any cleanup */
qemu_file_set_blocking(f, false);
@@ -1668,7 +1676,7 @@ static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis)
/* Start up the listening thread and wait for it to signal ready */
qemu_sem_init(&mis->listen_thread_sem, 0);
qemu_thread_create(&mis->listen_thread, "postcopy/listen",
- postcopy_ram_listen_thread, mis->from_src_file,
+ postcopy_ram_listen_thread, NULL,
QEMU_THREAD_DETACHED);
qemu_sem_wait(&mis->listen_thread_sem);
qemu_sem_destroy(&mis->listen_thread_sem);
@@ -2055,11 +2063,44 @@ void qemu_loadvm_state_cleanup(void)
}
}
+/* Return true if we should continue the migration, or false. */
+static bool postcopy_pause_incoming(MigrationIncomingState *mis)
+{
+ trace_postcopy_pause_incoming();
+
+ migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
+ MIGRATION_STATUS_POSTCOPY_PAUSED);
+
+ assert(mis->from_src_file);
+ qemu_file_shutdown(mis->from_src_file);
+ qemu_fclose(mis->from_src_file);
+ mis->from_src_file = NULL;
+
+ assert(mis->to_src_file);
+ qemu_file_shutdown(mis->to_src_file);
+ qemu_mutex_lock(&mis->rp_mutex);
+ qemu_fclose(mis->to_src_file);
+ mis->to_src_file = NULL;
+ qemu_mutex_unlock(&mis->rp_mutex);
+
+ error_report("Detected IO failure for postcopy. "
+ "Migration paused.");
+
+ while (mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
+ qemu_sem_wait(&mis->postcopy_pause_sem_dst);
+ }
+
+ trace_postcopy_pause_incoming_continued();
+
+ return true;
+}
+
static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis)
{
uint8_t section_type;
int ret = 0;
+retry:
while (true) {
section_type = qemu_get_byte(f);
@@ -2104,6 +2145,24 @@ static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis)
out:
if (ret < 0) {
qemu_file_set_error(f, ret);
+
+ /*
+ * Detect whether it is:
+ *
+ * 1. postcopy running (after receiving all device data, which
+ * must be in POSTCOPY_INCOMING_RUNNING state. Note that
+ * POSTCOPY_INCOMING_LISTENING is still not enough, it's
+ * still receiving device states).
+ * 2. network failure (-EIO)
+ *
+ * If so, we try to wait for a recovery.
+ */
+ if (postcopy_state_get() == POSTCOPY_INCOMING_RUNNING &&
+ ret == -EIO && postcopy_pause_incoming(mis)) {
+ /* Reset f to point to the newly created channel */
+ f = mis->from_src_file;
+ goto retry;
+ }
}
return ret;
}
diff --git a/migration/trace-events b/migration/trace-events
index 409b4b8be3..e23ec019be 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -100,6 +100,8 @@ open_return_path_on_source(void) ""
open_return_path_on_source_continue(void) ""
postcopy_start(void) ""
postcopy_pause_continued(void) ""
+postcopy_pause_incoming(void) ""
+postcopy_pause_incoming_continued(void) ""
postcopy_start_set_run(void) ""
source_return_path_thread_bad_end(void) ""
source_return_path_thread_end(void) ""