From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:47740) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RB5zX-0001dB-No for qemu-devel@nongnu.org; Tue, 04 Oct 2011 10:29:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RB5zV-0007t6-Qh for qemu-devel@nongnu.org; Tue, 04 Oct 2011 10:29:07 -0400 Received: from mail-iy0-f173.google.com ([209.85.210.173]:45557) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RB5zV-0007sy-II for qemu-devel@nongnu.org; Tue, 04 Oct 2011 10:29:05 -0400 Received: by iagf6 with SMTP id f6so765060iag.4 for ; Tue, 04 Oct 2011 07:29:04 -0700 (PDT) Message-ID: <4E8B182D.9050603@codemonkey.ws> Date: Tue, 04 Oct 2011 09:29:01 -0500 From: Anthony Liguori MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 17/23] migration: make sure we always have a migration state List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Quintela Cc: qemu-devel@nongnu.org On 09/23/2011 07:57 AM, Juan Quintela wrote: > This cleans up a lot the code as we don't have to check anymore if > the variable is NULL or not. > > We don't make it static, because when we integrate fault tolerance, we > can have several migrations at once. > > Signed-off-by: Juan Quintela > --- > migration.c | 126 +++++++++++++++++++++++++--------------------------------- > 1 files changed, 54 insertions(+), 72 deletions(-) > > diff --git a/migration.c b/migration.c > index 1cc21f0..c382383 100644 > --- a/migration.c > +++ b/migration.c > @@ -34,7 +34,13 @@ > /* Migration speed throttling */ > static int64_t max_throttle = (32<< 20); > > -static MigrationState *current_migration; > +/* When we add fault tolerance, we could have several > + migrations at once. For now we don't need to add > + dynamic creation of migration */ > +static MigrationState current_migration_static = { > + .state = MIG_STATE_NONE, > +}; > +static MigrationState *current_migration =¤t_migration_static; This doesn't make sense to me. We can have two migration states that are both in the MIG_STATE_NONE? What does that actually mean? I don't see the point in making migration state nullable via the state member other than avoiding the if (s == NULL) check. Regards, Anthony Liguori > > static NotifierList migration_state_notifiers = > NOTIFIER_LIST_INITIALIZER(migration_state_notifiers); > @@ -136,37 +142,34 @@ void do_info_migrate(Monitor *mon, QObject **ret_data) > { > QDict *qdict; > > - if (current_migration) { > - > - switch (current_migration->state) { > - case MIG_STATE_NONE: > - /* no migration has happened ever */ > - break; > - case MIG_STATE_ACTIVE: > - qdict = qdict_new(); > - qdict_put(qdict, "status", qstring_from_str("active")); > - > - migrate_put_status(qdict, "ram", ram_bytes_transferred(), > - ram_bytes_remaining(), ram_bytes_total()); > - > - if (blk_mig_active()) { > - migrate_put_status(qdict, "disk", blk_mig_bytes_transferred(), > - blk_mig_bytes_remaining(), > - blk_mig_bytes_total()); > - } > - > - *ret_data = QOBJECT(qdict); > - break; > - case MIG_STATE_COMPLETED: > - *ret_data = qobject_from_jsonf("{ 'status': 'completed' }"); > - break; > - case MIG_STATE_ERROR: > - *ret_data = qobject_from_jsonf("{ 'status': 'failed' }"); > - break; > - case MIG_STATE_CANCELLED: > - *ret_data = qobject_from_jsonf("{ 'status': 'cancelled' }"); > - break; > + switch (current_migration->state) { > + case MIG_STATE_NONE: > + /* no migration has happened ever */ > + break; > + case MIG_STATE_ACTIVE: > + qdict = qdict_new(); > + qdict_put(qdict, "status", qstring_from_str("active")); > + > + migrate_put_status(qdict, "ram", ram_bytes_transferred(), > + ram_bytes_remaining(), ram_bytes_total()); > + > + if (blk_mig_active()) { > + migrate_put_status(qdict, "disk", blk_mig_bytes_transferred(), > + blk_mig_bytes_remaining(), > + blk_mig_bytes_total()); > } > + > + *ret_data = QOBJECT(qdict); > + break; > + case MIG_STATE_COMPLETED: > + *ret_data = qobject_from_jsonf("{ 'status': 'completed' }"); > + break; > + case MIG_STATE_ERROR: > + *ret_data = qobject_from_jsonf("{ 'status': 'failed' }"); > + break; > + case MIG_STATE_CANCELLED: > + *ret_data = qobject_from_jsonf("{ 'status': 'cancelled' }"); > + break; > } > } > > @@ -357,11 +360,7 @@ void remove_migration_state_change_notifier(Notifier *notify) > > int get_migration_state(void) > { > - if (current_migration) { > - return current_migration->state; > - } else { > - return MIG_STATE_ERROR; > - } > + return current_migration->state; > } > > void migrate_fd_connect(MigrationState *s) > @@ -386,28 +385,23 @@ void migrate_fd_connect(MigrationState *s) > migrate_fd_put_ready(s); > } > > -static MigrationState *migrate_create_state(Monitor *mon, > - int64_t bandwidth_limit, > - int detach, int blk, int inc) > +static void migrate_init_state(Monitor *mon, int64_t bandwidth_limit, > + int detach, int blk, int inc) > { > - MigrationState *s = g_malloc0(sizeof(*s)); > - > - s->blk = blk; > - s->shared = inc; > - s->mon = NULL; > - s->bandwidth_limit = bandwidth_limit; > - s->state = MIG_STATE_NONE; > + memset(current_migration, 0, sizeof(current_migration)); > + current_migration->blk = blk; > + current_migration->shared = inc; > + current_migration->mon = NULL; > + current_migration->bandwidth_limit = bandwidth_limit; > + current_migration->state = MIG_STATE_NONE; > > if (!detach) { > - migrate_fd_monitor_suspend(s, mon); > + migrate_fd_monitor_suspend(current_migration, mon); > } > - > - return s; > } > > int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data) > { > - MigrationState *s = NULL; > const char *p; > int detach = qdict_get_try_bool(qdict, "detach", 0); > int blk = qdict_get_try_bool(qdict, "blk", 0); > @@ -415,8 +409,7 @@ int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data) > const char *uri = qdict_get_str(qdict, "uri"); > int ret; > > - if (current_migration&& > - current_migration->state == MIG_STATE_ACTIVE) { > + if (current_migration->state == MIG_STATE_ACTIVE) { > monitor_printf(mon, "migration already in progress\n"); > return -1; > } > @@ -425,43 +418,35 @@ int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data) > return -1; > } > > - s = migrate_create_state(mon, max_throttle, detach, blk, inc); > + migrate_init_state(mon, max_throttle, detach, blk, inc); > > if (strstart(uri, "tcp:",&p)) { > - ret = tcp_start_outgoing_migration(s, p); > + ret = tcp_start_outgoing_migration(current_migration, p); > #if !defined(WIN32) > } else if (strstart(uri, "exec:",&p)) { > - ret = exec_start_outgoing_migration(s, p); > + ret = exec_start_outgoing_migration(current_migration, p); > } else if (strstart(uri, "unix:",&p)) { > - ret = unix_start_outgoing_migration(s, p); > + ret = unix_start_outgoing_migration(current_migration, p); > } else if (strstart(uri, "fd:",&p)) { > - ret = fd_start_outgoing_migration(s, p); > + ret = fd_start_outgoing_migration(current_migration, p); > #endif > } else { > monitor_printf(mon, "unknown migration protocol: %s\n", uri); > - ret = -EINVAL; > - goto free_migrate_state; > + return -EINVAL; > } > > if (ret< 0) { > monitor_printf(mon, "migration failed\n"); > - goto free_migrate_state; > + return ret; > } > > - g_free(current_migration); > - current_migration = s; > notifier_list_notify(&migration_state_notifiers, NULL); > return 0; > -free_migrate_state: > - g_free(s); > - return -1; > } > > int do_migrate_cancel(Monitor *mon, const QDict *qdict, QObject **ret_data) > { > - if (current_migration) { > - migrate_fd_cancel(current_migration); > - } > + migrate_fd_cancel(current_migration); > return 0; > } > > @@ -475,10 +460,7 @@ int do_migrate_set_speed(Monitor *mon, const QDict *qdict, QObject **ret_data) > } > max_throttle = d; > > - if (current_migration) { > - qemu_file_set_rate_limit(current_migration->file, max_throttle); > - } > - > + qemu_file_set_rate_limit(current_migration->file, max_throttle); > return 0; > } >