From 389775d1f67b2c8f44f9473b1e5363735972e389 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Thu, 12 Nov 2015 15:38:27 +0000 Subject: [PATCH] migration_init: Fix lock initialisation/make it explicit Peter reported a lock error on MacOS after my a82d593b patch. migrate_get_current does one-time initialisation of a bunch of variables. migrate_init does reinitialisation even on a 2nd migrate after a cancel. The problem here was that I'd initialised the mutex in migrate_get_current, and the memset in migrate_init corrupted it. Remove the memset and replace it by explicit initialisation of fields that need initialising; this also turns out to be simpler than the old code that had to preserve some fields. Reported-by: Peter Maydell Signed-off-by: Dr. David Alan Gilbert Fixes: a82d593b Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/migration.c | 51 +++++++++++++++++++------------------------ 1 file changed, 22 insertions(+), 29 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index 9bd2ce73ad..7e4e27b57d 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -902,38 +902,31 @@ bool migration_in_postcopy(MigrationState *s) MigrationState *migrate_init(const MigrationParams *params) { MigrationState *s = migrate_get_current(); - int64_t bandwidth_limit = s->bandwidth_limit; - bool enabled_capabilities[MIGRATION_CAPABILITY_MAX]; - int64_t xbzrle_cache_size = s->xbzrle_cache_size; - int compress_level = s->parameters[MIGRATION_PARAMETER_COMPRESS_LEVEL]; - int compress_thread_count = - s->parameters[MIGRATION_PARAMETER_COMPRESS_THREADS]; - int decompress_thread_count = - s->parameters[MIGRATION_PARAMETER_DECOMPRESS_THREADS]; - int x_cpu_throttle_initial = - s->parameters[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL]; - int x_cpu_throttle_increment = - s->parameters[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT]; - memcpy(enabled_capabilities, s->enabled_capabilities, - sizeof(enabled_capabilities)); - - memset(s, 0, sizeof(*s)); + /* + * Reinitialise all migration state, except + * parameters/capabilities that the user set, and + * locks. + */ + s->bytes_xfer = 0; + s->xfer_limit = 0; + s->cleanup_bh = 0; + s->file = NULL; + s->state = MIGRATION_STATUS_NONE; s->params = *params; - memcpy(s->enabled_capabilities, enabled_capabilities, - sizeof(enabled_capabilities)); - s->xbzrle_cache_size = xbzrle_cache_size; + s->rp_state.from_dst_file = NULL; + s->rp_state.error = false; + s->mbps = 0.0; + s->downtime = 0; + s->expected_downtime = 0; + s->dirty_pages_rate = 0; + s->dirty_bytes_rate = 0; + s->setup_time = 0; + s->dirty_sync_count = 0; + s->start_postcopy = false; + s->migration_thread_running = false; + s->last_req_rb = NULL; - s->parameters[MIGRATION_PARAMETER_COMPRESS_LEVEL] = compress_level; - s->parameters[MIGRATION_PARAMETER_COMPRESS_THREADS] = - compress_thread_count; - s->parameters[MIGRATION_PARAMETER_DECOMPRESS_THREADS] = - decompress_thread_count; - s->parameters[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL] = - x_cpu_throttle_initial; - s->parameters[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT] = - x_cpu_throttle_increment; - s->bandwidth_limit = bandwidth_limit; migrate_set_state(s, MIGRATION_STATUS_NONE, MIGRATION_STATUS_SETUP); QSIMPLEQ_INIT(&s->src_page_requests);