From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47726) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1db0K6-0001r2-DV for qemu-devel@nongnu.org; Fri, 28 Jul 2017 04:08:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1db0K5-0001tJ-9A for qemu-devel@nongnu.org; Fri, 28 Jul 2017 04:08:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55520) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1db0K5-0001si-0Q for qemu-devel@nongnu.org; Fri, 28 Jul 2017 04:08:37 -0400 From: Peter Xu Date: Fri, 28 Jul 2017 16:06:38 +0800 Message-Id: <1501229198-30588-30-git-send-email-peterx@redhat.com> In-Reply-To: <1501229198-30588-1-git-send-email-peterx@redhat.com> References: <1501229198-30588-1-git-send-email-peterx@redhat.com> Subject: [Qemu-devel] [RFC 29/29] migration: reset migrate thread vars when resumed List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Laurent Vivier , Alexey Perevalov , Juan Quintela , Andrea Arcangeli , "Dr . David Alan Gilbert" , peterx@redhat.com Firstly, MigThrError enumeration is introduced to describe the error in migration_detect_error() better. This gives the migration_thread() a chance to know whether a recovery has happened. Then, if a recovery is detected, migration_thread() will reset its local variables to prepare for that. Signed-off-by: Peter Xu --- migration/migration.c | 40 +++++++++++++++++++++++++++++----------- 1 file changed, 29 insertions(+), 11 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index ecebe30..439bc22 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -2159,6 +2159,15 @@ static bool postcopy_should_start(MigrationState *s) return atomic_read(&s->start_postcopy) || s->start_postcopy_fast; } +typedef enum MigThrError { + /* No error detected */ + MIG_THR_ERR_NONE = 0, + /* Detected error, but resumed successfully */ + MIG_THR_ERR_RECOVERED = 1, + /* Detected fatal error, need to exit */ + MIG_THR_ERR_FATAL = 2, +} MigThrError; + static int postcopy_resume_handshake(MigrationState *s) { qemu_mutex_lock(&s->resume_lock); @@ -2209,10 +2218,10 @@ static int postcopy_do_resume(MigrationState *s) /* * We don't return until we are in a safe state to continue current - * postcopy migration. Returns true to continue the migration, or - * false to terminate current migration. + * postcopy migration. Returns MIG_THR_ERR_RECOVERED if recovered, or + * MIG_THR_ERR_FATAL if unrecovery failure happened. */ -static bool postcopy_pause(MigrationState *s) +static MigThrError postcopy_pause(MigrationState *s) { assert(s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE); @@ -2247,7 +2256,7 @@ do_pause: if (postcopy_do_resume(s) == 0) { /* Let's continue! */ trace_postcopy_pause_continued(); - return true; + return MIG_THR_ERR_RECOVERED; } else { /* * Something wrong happened during the recovery, let's @@ -2258,12 +2267,11 @@ do_pause: } } else { /* This is not right... Time to quit. */ - return false; + return MIG_THR_ERR_FATAL; } } -/* Return true if we want to stop the migration, otherwise false. */ -static bool migration_detect_error(MigrationState *s) +static MigThrError migration_detect_error(MigrationState *s) { int ret; @@ -2272,7 +2280,7 @@ static bool migration_detect_error(MigrationState *s) if (!ret) { /* Everything is fine */ - return false; + return MIG_THR_ERR_NONE; } if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE && ret == -EIO) { @@ -2281,7 +2289,7 @@ static bool migration_detect_error(MigrationState *s) * while. After that, it can be continued by a * recovery phase. */ - return !postcopy_pause(s); + return postcopy_pause(s); } else { /* * For precopy (or postcopy with error outside IO), we fail @@ -2291,7 +2299,7 @@ static bool migration_detect_error(MigrationState *s) trace_migration_thread_file_err(); /* Time to stop the migration, now. */ - return true; + return MIG_THR_ERR_FATAL; } } @@ -2319,6 +2327,7 @@ static void *migration_thread(void *opaque) /* The active state we expect to be in; ACTIVE or POSTCOPY_ACTIVE */ enum MigrationStatus current_active_state = MIGRATION_STATUS_ACTIVE; bool enable_colo = migrate_colo_enabled(); + MigThrError thr_error; rcu_register_thread(); @@ -2395,8 +2404,17 @@ static void *migration_thread(void *opaque) * Try to detect any kind of failures, and see whether we * should stop the migration now. */ - if (migration_detect_error(s)) { + thr_error = migration_detect_error(s); + if (thr_error == MIG_THR_ERR_FATAL) { + /* Stop migration */ break; + } else if (thr_error == MIG_THR_ERR_RECOVERED) { + /* + * Just recovered from a e.g. network failure, reset all + * the local variables. + */ + initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + initial_bytes = 0; } current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); -- 2.7.4