From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34779) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fDpIw-0006Ln-7J for qemu-devel@nongnu.org; Wed, 02 May 2018 06:48:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fDpIv-0002m6-5C for qemu-devel@nongnu.org; Wed, 02 May 2018 06:48:10 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:42484 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fDpIu-0002ld-U8 for qemu-devel@nongnu.org; Wed, 02 May 2018 06:48:09 -0400 From: Peter Xu Date: Wed, 2 May 2018 18:47:21 +0800 Message-Id: <20180502104740.12123-6-peterx@redhat.com> In-Reply-To: <20180502104740.12123-1-peterx@redhat.com> References: <20180502104740.12123-1-peterx@redhat.com> Subject: [Qemu-devel] [PATCH v8 05/24] migration: allow src return path to pause List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Alexey Perevalov , "Daniel P . Berrange" , Juan Quintela , Andrea Arcangeli , "Dr . David Alan Gilbert" , peterx@redhat.com Let the thread pause for network issues. Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Peter Xu --- migration/migration.h | 1 + migration/migration.c | 35 +++++++++++++++++++++++++++++++++-- migration/trace-events | 2 ++ 3 files changed, 36 insertions(+), 2 deletions(-) diff --git a/migration/migration.h b/migration/migration.h index ad96cc2c85..db28a66a92 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -200,6 +200,7 @@ struct MigrationState /* Needed by postcopy-pause state */ QemuSemaphore postcopy_pause_sem; + QemuSemaphore postcopy_pause_rp_sem; }; void migrate_set_state(int *state, int old_state, int new_state); diff --git a/migration/migration.c b/migration/migration.c index 5ad3a79354..09dbf5350c 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -1774,6 +1774,18 @@ static void migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname, } } +/* Return true to retry, false to quit */ +static bool postcopy_pause_return_path_thread(MigrationState *s) +{ + trace_postcopy_pause_return_path(); + + qemu_sem_wait(&s->postcopy_pause_rp_sem); + + trace_postcopy_pause_return_path_continued(); + + return true; +} + /* * Handles messages sent on the return path towards the source VM * @@ -1790,6 +1802,8 @@ static void *source_return_path_thread(void *opaque) int res; trace_source_return_path_thread_entry(); + +retry: while (!ms->rp_state.error && !qemu_file_get_error(rp) && migration_is_setup_or_active(ms->state)) { trace_source_return_path_thread_loop_top(); @@ -1881,13 +1895,28 @@ static void *source_return_path_thread(void *opaque) break; } } - if (qemu_file_get_error(rp)) { + +out: + res = qemu_file_get_error(rp); + if (res) { + if (res == -EIO) { + /* + * Maybe there is something we can do: it looks like a + * network down issue, and we pause for a recovery. + */ + if (postcopy_pause_return_path_thread(ms)) { + /* Reload rp, reset the rest */ + rp = ms->rp_state.from_dst_file; + ms->rp_state.error = false; + goto retry; + } + } + trace_source_return_path_thread_bad_end(); mark_source_rp_bad(ms); } trace_source_return_path_thread_end(); -out: ms->rp_state.from_dst_file = NULL; qemu_fclose(rp); return NULL; @@ -2695,6 +2724,7 @@ static void migration_instance_finalize(Object *obj) g_free(params->tls_creds); qemu_sem_destroy(&ms->pause_sem); qemu_sem_destroy(&ms->postcopy_pause_sem); + qemu_sem_destroy(&ms->postcopy_pause_rp_sem); error_free(ms->error); } @@ -2726,6 +2756,7 @@ static void migration_instance_init(Object *obj) params->has_xbzrle_cache_size = true; qemu_sem_init(&ms->postcopy_pause_sem, 0); + qemu_sem_init(&ms->postcopy_pause_rp_sem, 0); } /* diff --git a/migration/trace-events b/migration/trace-events index e23ec019be..cd971bf9fe 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -99,6 +99,8 @@ migration_thread_setup_complete(void) "" open_return_path_on_source(void) "" open_return_path_on_source_continue(void) "" postcopy_start(void) "" +postcopy_pause_return_path(void) "" +postcopy_pause_return_path_continued(void) "" postcopy_pause_continued(void) "" postcopy_pause_incoming(void) "" postcopy_pause_incoming_continued(void) "" -- 2.14.3