diff mbox series

[PULL,23/41] migration: wakeup dst ram-load-thread for recover

Message ID 20180509112406.6183-24-quintela@redhat.com
State New
Headers show
Series [PULL,01/41] migration: fix saving normal page even if it's been compressed | expand

Commit Message

Juan Quintela May 9, 2018, 11:23 a.m. UTC 
From: Peter Xu <peterx@redhat.com>

On the destination side, we cannot wake up all the threads when we got
reconnected. The first thing to do is to wake up the main load thread,
so that we can continue to receive valid messages from source again and
reply when needed.

At this point, we switch the destination VM state from postcopy-paused
back to postcopy-recover.

Now we are finally ready to do the resume logic.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-11-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/migration.c | 30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/migration/migration.c b/migration/migration.c
index 4ab637a1fe..ec3bc9ae20 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -440,8 +440,34 @@  void migration_incoming_process(void)
 
 void migration_fd_process_incoming(QEMUFile *f)
 {
-    migration_incoming_setup(f);
-    migration_incoming_process();
+    MigrationIncomingState *mis = migration_incoming_get_current();
+
+    if (mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
+        /* Resumed from a paused postcopy migration */
+
+        mis->from_src_file = f;
+        /* Postcopy has standalone thread to do vm load */
+        qemu_file_set_blocking(f, true);
+
+        /* Re-configure the return path */
+        mis->to_src_file = qemu_file_get_return_path(f);
+
+        migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_PAUSED,
+                          MIGRATION_STATUS_POSTCOPY_RECOVER);
+
+        /*
+         * Here, we only wake up the main loading thread (while the
+         * fault thread will still be waiting), so that we can receive
+         * commands from source now, and answer it if needed. The
+         * fault thread will be woken up afterwards until we are sure
+         * that source is ready to reply to page requests.
+         */
+        qemu_sem_post(&mis->postcopy_pause_sem_dst);
+    } else {
+        /* New incoming migration */
+        migration_incoming_setup(f);
+        migration_incoming_process();
+    }
 }
 
 void migration_ioc_process_incoming(QIOChannel *ioc)