From 6decec931149ae50d84e2b264bf93f3676d5b3f9 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Thu, 5 Nov 2015 18:10:47 +0000 Subject: Return path: Send responses from destination to source Add migrate_send_rp_message to send a message from destination to source along the return path. (It uses a mutex to let it be called from multiple threads) Add migrate_send_rp_shut to send a 'shut' message to indicate the destination is finished with the RP. Add migrate_send_rp_ack to send a 'PONG' message in response to a PING Use it in the MSG_RP_PING handler Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Amit Shah Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/migration.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ migration/savevm.c | 2 +- 2 files changed, 46 insertions(+), 1 deletion(-) (limited to 'migration') diff --git a/migration/migration.c b/migration/migration.c index bb7dcb9..8380e2f 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -97,6 +97,7 @@ MigrationIncomingState *migration_incoming_state_new(QEMUFile* f) mis_current = g_new0(MigrationIncomingState, 1); mis_current->from_src_file = f; QLIST_INIT(&mis_current->loadvm_handlers); + qemu_mutex_init(&mis_current->rp_mutex); return mis_current; } @@ -344,6 +345,50 @@ void process_incoming_migration(QEMUFile *f) qemu_coroutine_enter(co, f); } +/* + * Send a message on the return channel back to the source + * of the migration. + */ +void migrate_send_rp_message(MigrationIncomingState *mis, + enum mig_rp_message_type message_type, + uint16_t len, void *data) +{ + trace_migrate_send_rp_message((int)message_type, len); + qemu_mutex_lock(&mis->rp_mutex); + qemu_put_be16(mis->to_src_file, (unsigned int)message_type); + qemu_put_be16(mis->to_src_file, len); + qemu_put_buffer(mis->to_src_file, data, len); + qemu_fflush(mis->to_src_file); + qemu_mutex_unlock(&mis->rp_mutex); +} + +/* + * Send a 'SHUT' message on the return channel with the given value + * to indicate that we've finished with the RP. Non-0 value indicates + * error. + */ +void migrate_send_rp_shut(MigrationIncomingState *mis, + uint32_t value) +{ + uint32_t buf; + + buf = cpu_to_be32(value); + migrate_send_rp_message(mis, MIG_RP_MSG_SHUT, sizeof(buf), &buf); +} + +/* + * Send a 'PONG' message on the return channel with the given value + * (normally in response to a 'PING') + */ +void migrate_send_rp_pong(MigrationIncomingState *mis, + uint32_t value) +{ + uint32_t buf; + + buf = cpu_to_be32(value); + migrate_send_rp_message(mis, MIG_RP_MSG_PONG, sizeof(buf), &buf); +} + /* amount of nanoseconds we are willing to wait for migration to be down. * the choice of nanoseconds is because it is the maximum resolution that * get_clock() can achieve. It is an internal measure. All user-visible diff --git a/migration/savevm.c b/migration/savevm.c index d47c55b..1ffe7b0 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1103,7 +1103,7 @@ static int loadvm_process_command(QEMUFile *f) tmp32); return -1; } - /* migrate_send_rp_pong(mis, tmp32); TODO: gets added later */ + migrate_send_rp_pong(mis, tmp32); break; } -- cgit v1.1