Merge tag 'migration-20231011-pull-request' of https://gitlab.com/juan.quintela/qemu into staging

Migration Pull request (20231011 edition)

Hi

In this pull request:

- Markus RDMA cleanup series
- recover fixes from peter
- migration capability from fabiano
- negative migration test from fabiano.

Please, pull.

Thanks, Juan.

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# gpg: Signature made Wed 11 Oct 2023 05:21:19 EDT
# gpg:                using RSA key 1899FF8EDEBF58CCEE034B82F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>" [full]
# gpg:                 aka "Juan Quintela <quintela@trasno.org>" [full]
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* tag 'migration-20231011-pull-request' of https://gitlab.com/juan.quintela/qemu: (65 commits)
  migration: Add migration_rp_wait|kick()
  migration: Remember num of ramblocks to sync during recovery
  qemufile: Always return a verbose error
  migration: Introduce migrate_has_error()
  migration: Display error in query-migrate irrelevant of status
  migration/rdma: Replace flawed device detail dump by tracing
  migration/rdma: Use error_report() & friends instead of stderr
  migration/rdma: Downgrade qemu_rdma_cleanup() errors to warnings
  migration/rdma: Silence qemu_rdma_register_and_get_keys()
  migration/rdma: Silence qemu_rdma_block_for_wrid()
  migration/rdma: Don't report received completion events as error
  migration/rdma: Silence qemu_rdma_reg_control()
  migration/rdma: Silence qemu_rdma_connect()
  migration/rdma: Silence qemu_rdma_resolve_host()
  migration/rdma: Convert qemu_rdma_alloc_pd_cq() to Error
  migration/rdma: Convert qemu_rdma_post_recv_control() to Error
  migration/rdma: Convert qemu_rdma_post_send_control() to Error
  migration/rdma: Convert qemu_rdma_write() to Error
  migration/rdma: Convert qemu_rdma_write_one() to Error
  migration/rdma: Convert qemu_rdma_write_flush() to Error
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

migration/migration.c

@@ -431,13 +431,16 @@ void migrate_add_address(SocketAddress *address)
 static void qemu_start_incoming_migration(const char *uri, Error **errp)
 {
     const char *p = NULL;
+    MigrationIncomingState *mis = migration_incoming_get_current();
 
     /* URI is not suitable for migration? */
     if (!migration_channels_and_uri_compatible(uri, errp)) {
         return;
     }
 
-    qapi_event_send_migration(MIGRATION_STATUS_SETUP);
+    migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
+                      MIGRATION_STATUS_SETUP);
+
     if (strstart(uri, "tcp:", &p) ||
         strstart(uri, "unix:", NULL) ||
         strstart(uri, "vsock:", NULL)) {
@@ -531,7 +534,7 @@ process_incoming_migration_co(void *opaque)
 
     mis->largest_page_size = qemu_ram_pagesize_largest();
     postcopy_state_set(POSTCOPY_INCOMING_NONE);
-    migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
+    migrate_set_state(&mis->state, MIGRATION_STATUS_SETUP,
                       MIGRATION_STATUS_ACTIVE);
 
     mis->loadvm_co = qemu_coroutine_self();
@@ -1057,9 +1060,6 @@ static void fill_source_migration_info(MigrationInfo *info)
         break;
     case MIGRATION_STATUS_FAILED:
         info->has_status = true;
-        if (s->error) {
-            info->error_desc = g_strdup(error_get_pretty(s->error));
-        }
         break;
     case MIGRATION_STATUS_CANCELLED:
         info->has_status = true;
@@ -1069,6 +1069,11 @@ static void fill_source_migration_info(MigrationInfo *info)
         break;
     }
     info->status = state;
+
+    QEMU_LOCK_GUARD(&s->error_mutex);
+    if (s->error) {
+        info->error_desc = g_strdup(error_get_pretty(s->error));
+    }
 }
 
 static void fill_destination_migration_info(MigrationInfo *info)
@@ -1229,6 +1234,13 @@ void migrate_set_error(MigrationState *s, const Error *error)
     }
 }
 
+bool migrate_has_error(MigrationState *s)
+{
+    /* The lock is not helpful here, but still follow the rule */
+    QEMU_LOCK_GUARD(&s->error_mutex);
+    return qatomic_read(&s->error);
+}
+
 static void migrate_error_free(MigrationState *s)
 {
     QEMU_LOCK_GUARD(&s->error_mutex);
@@ -1751,6 +1763,16 @@ static void mark_source_rp_bad(MigrationState *s)
     s->rp_state.error = true;
 }
 
+void migration_rp_wait(MigrationState *s)
+{
+    qemu_sem_wait(&s->rp_state.rp_sem);
+}
+
+void migration_rp_kick(MigrationState *s)
+{
+    qemu_sem_post(&s->rp_state.rp_sem);
+}
+
 static struct rp_cmd_args {
     ssize_t     len; /* -1 = variable */
     const char *name;
@@ -1823,7 +1845,7 @@ static int migrate_handle_rp_resume_ack(MigrationState *s, uint32_t value)
                       MIGRATION_STATUS_POSTCOPY_ACTIVE);
 
     /* Notify send thread that time to continue send pages */
-    qemu_sem_post(&s->rp_state.rp_sem);
+    migration_rp_kick(s);
 
     return 0;
 }
@@ -2452,7 +2474,7 @@ static int postcopy_resume_handshake(MigrationState *s)
     qemu_savevm_send_postcopy_resume(s->to_dst_file);
 
     while (s->state == MIGRATION_STATUS_POSTCOPY_RECOVER) {
-        qemu_sem_wait(&s->rp_state.rp_sem);
+        migration_rp_wait(s);
     }
 
     if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {

migration/migration.h

@@ -316,6 +316,12 @@ struct MigrationState {
          * be cleared in the rp_thread!
          */
         bool          rp_thread_created;
+        /*
+         * Used to synchronize between migration main thread and return
+         * path thread.  The migration thread can wait() on this sem, while
+         * other threads (e.g., return path thread) can kick it using a
+         * post().
+         */
         QemuSemaphore rp_sem;
         /*
          * We post to this when we got one PONG from dest. So far it's an
@@ -476,6 +482,7 @@ bool  migration_has_all_channels(void);
 uint64_t migrate_max_downtime(void);
 
 void migrate_set_error(MigrationState *s, const Error *error);
+bool migrate_has_error(MigrationState *s);
 
 void migrate_fd_connect(MigrationState *s, Error *error_in);
 
@@ -526,4 +533,13 @@ void migration_populate_vfio_info(MigrationInfo *info);
 void migration_reset_vfio_bytes_transferred(void);
 void postcopy_temp_page_reset(PostcopyTmpPage *tmp_page);
 
+/* Migration thread waiting for return path thread. */
+void migration_rp_wait(MigrationState *s);
+/*
+ * Kick the migration thread waiting for return path messages.  NOTE: the
+ * name can be slightly confusing (when read as "kick the rp thread"), just
+ * to remember the target is always the migration thread.
+ */
+void migration_rp_kick(MigrationState *s);
+
 #endif

migration/options.c

@@ -1408,20 +1408,25 @@ void qmp_migrate_set_parameters(MigrateSetParameters *params, Error **errp)
 {
     MigrationParameters tmp;
 
-    /* TODO Rewrite "" to null instead */
+    /* TODO Rewrite "" to null instead for all three tls_* parameters */
     if (params->tls_creds
         && params->tls_creds->type == QTYPE_QNULL) {
         qobject_unref(params->tls_creds->u.n);
         params->tls_creds->type = QTYPE_QSTRING;
         params->tls_creds->u.s = strdup("");
     }
-    /* TODO Rewrite "" to null instead */
     if (params->tls_hostname
         && params->tls_hostname->type == QTYPE_QNULL) {
         qobject_unref(params->tls_hostname->u.n);
         params->tls_hostname->type = QTYPE_QSTRING;
         params->tls_hostname->u.s = strdup("");
     }
+    if (params->tls_authz
+        && params->tls_authz->type == QTYPE_QNULL) {
+        qobject_unref(params->tls_authz->u.n);
+        params->tls_authz->type = QTYPE_QSTRING;
+        params->tls_authz->u.s = strdup("");
+    }
 
     migrate_params_test_apply(params, &tmp);
 

migration/qemu-file.c

@@ -142,15 +142,24 @@ void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks)
  *
  * Return negative error value if there has been an error on previous
  * operations, return 0 if no error happened.
- * Optional, it returns Error* in errp, but it may be NULL even if return value
- * is not 0.
  *
+ * If errp is specified, a verbose error message will be copied over.
  */
 static int qemu_file_get_error_obj(QEMUFile *f, Error **errp)
 {
+    if (!f->last_error) {
+        return 0;
+    }
+
+    /* There is an error */
     if (errp) {
-        *errp = f->last_error_obj ? error_copy(f->last_error_obj) : NULL;
+        if (f->last_error_obj) {
+            *errp = error_copy(f->last_error_obj);
+        } else {
+            error_setg_errno(errp, -f->last_error, "Channel error");
+        }
     }
+
     return f->last_error;
 }
 

migration/ram.c

@@ -394,6 +394,14 @@ struct RAMState {
     /* Queue of outstanding page requests from the destination */
     QemuMutex src_page_req_mutex;
     QSIMPLEQ_HEAD(, RAMSrcPageRequest) src_page_requests;
+
+    /*
+     * This is only used when postcopy is in recovery phase, to communicate
+     * between the migration thread and the return path thread on dirty
+     * bitmap synchronizations.  This field is unused in other stages of
+     * RAM migration.
+     */
+    unsigned int postcopy_bmap_sync_requested;
 };
 typedef struct RAMState RAMState;
 
@@ -4119,21 +4127,21 @@ static int ram_dirty_bitmap_sync_all(MigrationState *s, RAMState *rs)
 {
     RAMBlock *block;
     QEMUFile *file = s->to_dst_file;
-    int ramblock_count = 0;
 
     trace_ram_dirty_bitmap_sync_start();
 
+    qatomic_set(&rs->postcopy_bmap_sync_requested, 0);
     RAMBLOCK_FOREACH_NOT_IGNORED(block) {
         qemu_savevm_send_recv_bitmap(file, block->idstr);
         trace_ram_dirty_bitmap_request(block->idstr);
-        ramblock_count++;
+        qatomic_inc(&rs->postcopy_bmap_sync_requested);
     }
 
     trace_ram_dirty_bitmap_sync_wait();
 
     /* Wait until all the ramblocks' dirty bitmap synced */
-    while (ramblock_count--) {
-        qemu_sem_wait(&s->rp_state.rp_sem);
+    while (qatomic_read(&rs->postcopy_bmap_sync_requested)) {
+        migration_rp_wait(s);
     }
 
     trace_ram_dirty_bitmap_sync_complete();
@@ -4141,11 +4149,6 @@ static int ram_dirty_bitmap_sync_all(MigrationState *s, RAMState *rs)
     return 0;
 }
 
-static void ram_dirty_bitmap_reload_notify(MigrationState *s)
-{
-    qemu_sem_post(&s->rp_state.rp_sem);
-}
-
 /*
  * Read the received bitmap, revert it as the initial dirty bitmap.
  * This is only used when the postcopy migration is paused but wants
@@ -4159,6 +4162,7 @@ int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *block)
     unsigned long *le_bitmap, nbits = block->used_length >> TARGET_PAGE_BITS;
     uint64_t local_size = DIV_ROUND_UP(nbits, 8);
     uint64_t size, end_mark;
+    RAMState *rs = ram_state;
 
     trace_ram_dirty_bitmap_reload_begin(block->idstr);
 
@@ -4225,11 +4229,16 @@ int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *block)
     /* We'll recalculate migration_dirty_pages in ram_state_resume_prepare(). */
     trace_ram_dirty_bitmap_reload_complete(block->idstr);
 
+    qatomic_dec(&rs->postcopy_bmap_sync_requested);
+
     /*
-     * We succeeded to sync bitmap for current ramblock. If this is
-     * the last one to sync, we need to notify the main send thread.
+     * We succeeded to sync bitmap for current ramblock. Always kick the
+     * migration thread to check whether all requested bitmaps are
+     * reloaded.  NOTE: it's racy to only kick when requested==0, because
+     * we don't know whether the migration thread may still be increasing
+     * it.
      */
-    ram_dirty_bitmap_reload_notify(s);
+    migration_rp_kick(s);
 
     ret = 0;
 out:

migration/savevm.c

@@ -2734,7 +2734,8 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis)
         qemu_mutex_unlock(&mis->postcopy_prio_thread_mutex);
     }
 
-    migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
+    /* Current state can be either ACTIVE or RECOVER */
+    migrate_set_state(&mis->state, mis->state,
                       MIGRATION_STATUS_POSTCOPY_PAUSED);
 
     /* Notify the fault thread for the invalidated file handle */

migration/trace-events

@@ -208,12 +208,14 @@ qemu_rdma_accept_incoming_migration(void) ""
 qemu_rdma_accept_incoming_migration_accepted(void) ""
 qemu_rdma_accept_pin_state(bool pin) "%d"
 qemu_rdma_accept_pin_verbsc(void *verbs) "Verbs context after listen: %p"
-qemu_rdma_block_for_wrid_miss(const char *wcompstr, int wcomp, const char *gcompstr, uint64_t req) "A Wanted wrid %s (%d) but got %s (%" PRIu64 ")"
+qemu_rdma_block_for_wrid_miss(uint64_t wcomp, uint64_t req) "A Wanted wrid %" PRIu64 " but got %" PRIu64
 qemu_rdma_cleanup_disconnect(void) ""
 qemu_rdma_close(void) ""
 qemu_rdma_connect_pin_all_requested(void) ""
 qemu_rdma_connect_pin_all_outcome(bool pin) "%d"
 qemu_rdma_dest_init_trying(const char *host, const char *ip) "%s => %s"
+qemu_rdma_dump_id_failed(const char *who) "%s RDMA Device opened, but can't query port information"
+qemu_rdma_dump_id(const char *who, const char *name, const char *dev_name, const char *dev_path, const char *ibdev_path, int transport, const char *transport_name) "%s RDMA Device opened: kernel name %s uverbs device name %s, infiniband_verbs class device path %s, infiniband class device path %s, transport: (%d) %s"
 qemu_rdma_dump_gid(const char *who, const char *src, const char *dst) "%s Source GID: %s, Dest GID: %s"
 qemu_rdma_exchange_get_response_start(const char *desc) "CONTROL: %s receiving..."
 qemu_rdma_exchange_get_response_none(const char *desc, int type) "Surprise: got %s (%d)"
@@ -222,9 +224,9 @@ qemu_rdma_exchange_send_waiting(const char *desc) "Waiting for response %s"
 qemu_rdma_exchange_send_received(const char *desc) "Response %s received."
 qemu_rdma_fill(size_t control_len, size_t size) "RDMA %zd of %zd bytes already in buffer"
 qemu_rdma_init_ram_blocks(int blocks) "Allocated %d local ram block structures"
-qemu_rdma_poll_recv(const char *compstr, int64_t comp, int64_t id, int sent) "completion %s #%" PRId64 " received (%" PRId64 ") left %d"
-qemu_rdma_poll_write(const char *compstr, int64_t comp, int left, uint64_t block, uint64_t chunk, void *local, void *remote) "completions %s (%" PRId64 ") left %d, block %" PRIu64 ", chunk: %" PRIu64 " %p %p"
-qemu_rdma_poll_other(const char *compstr, int64_t comp, int left) "other completion %s (%" PRId64 ") received left %d"
+qemu_rdma_poll_recv(uint64_t comp, int64_t id, int sent) "completion %" PRIu64 " received (%" PRId64 ") left %d"
+qemu_rdma_poll_write(uint64_t comp, int left, uint64_t block, uint64_t chunk, void *local, void *remote) "completions %" PRIu64 " left %d, block %" PRIu64 ", chunk: %" PRIu64 " %p %p"
+qemu_rdma_poll_other(uint64_t comp, int left) "other completion %" PRIu64 " received left %d"
 qemu_rdma_post_send_control(const char *desc) "CONTROL: sending %s.."
 qemu_rdma_register_and_get_keys(uint64_t len, void *start) "Registering %" PRIu64 " bytes @ %p"
 qemu_rdma_register_odp_mr(const char *name) "Try to register On-Demand Paging memory region: %s"

qapi/migration.json

@@ -230,9 +230,8 @@
 #     throttled during auto-converge.  This is only present when
 #     auto-converge has started throttling guest cpus.  (Since 2.7)
 #
-# @error-desc: the human readable error description string, when
-#     @status is 'failed'. Clients should not attempt to parse the
-#     error strings.  (Since 2.7)
+# @error-desc: the human readable error description string. Clients
+#     should not attempt to parse the error strings.  (Since 2.7)
 #
 # @postcopy-blocktime: total time when all vCPU were blocked during
 #     postcopy live migration.  This is only present when the

tests/qtest/libqtest.c

@@ -1259,6 +1259,28 @@ void qtest_memset(QTestState *s, uint64_t addr, uint8_t pattern, size_t size)
     qtest_rsp(s);
 }
 
+QDict *qtest_vqmp_assert_failure_ref(QTestState *qts,
+                                     const char *fmt, va_list args)
+{
+    QDict *response;
+    QDict *ret;
+
+    response = qtest_vqmp(qts, fmt, args);
+
+    g_assert(response);
+    if (!qdict_haskey(response, "error")) {
+        g_autoptr(GString) s = qobject_to_json_pretty(QOBJECT(response), true);
+        g_test_message("%s", s->str);
+    }
+    g_assert(qdict_haskey(response, "error"));
+    g_assert(!qdict_haskey(response, "return"));
+    ret = qdict_get_qdict(response, "error");
+    qobject_ref(ret);
+    qobject_unref(response);
+
+    return ret;
+}
+
 QDict *qtest_vqmp_assert_success_ref(QTestState *qts,
                                      const char *fmt, va_list args)
 {
@@ -1321,6 +1343,17 @@ void qtest_vqmp_fds_assert_success(QTestState *qts, int *fds, size_t nfds,
 }
 #endif /* !_WIN32 */
 
+QDict *qtest_qmp_assert_failure_ref(QTestState *qts, const char *fmt, ...)
+{
+    QDict *response;
+    va_list ap;
+
+    va_start(ap, fmt);
+    response = qtest_vqmp_assert_failure_ref(qts, fmt, ap);
+    va_end(ap);
+    return response;
+}
+
 QDict *qtest_qmp_assert_success_ref(QTestState *qts, const char *fmt, ...)
 {
     QDict *response;

tests/qtest/libqtest.h

@@ -810,6 +810,34 @@ void qtest_vqmp_fds_assert_success(QTestState *qts, int *fds, size_t nfds,
     G_GNUC_PRINTF(4, 0);
 #endif /* !_WIN32 */
 
+/**
+ * qtest_qmp_assert_failure_ref:
+ * @qts: QTestState instance to operate on
+ * @fmt: QMP message to send to qemu, formatted like
+ * qobject_from_jsonf_nofail().  See parse_interpolation() for what's
+ * supported after '%'.
+ *
+ * Sends a QMP message to QEMU, asserts that an 'error' key is present in
+ * the response, and returns the response.
+ */
+QDict *qtest_qmp_assert_failure_ref(QTestState *qts, const char *fmt, ...)
+    G_GNUC_PRINTF(2, 3);
+
+/**
+ * qtest_vqmp_assert_failure_ref:
+ * @qts: QTestState instance to operate on
+ * @fmt: QMP message to send to qemu, formatted like
+ * qobject_from_jsonf_nofail().  See parse_interpolation() for what's
+ * supported after '%'.
+ * @args: variable arguments for @fmt
+ *
+ * Sends a QMP message to QEMU, asserts that an 'error' key is present in
+ * the response, and returns the response.
+ */
+QDict *qtest_vqmp_assert_failure_ref(QTestState *qts,
+                                     const char *fmt, va_list args)
+    G_GNUC_PRINTF(2, 0);
+
 /**
  * qtest_qmp_assert_success_ref:
  * @qts: QTestState instance to operate on

tests/qtest/meson.build

@@ -317,6 +317,7 @@ qtests = {
   'tpm-tis-i2c-test': [io, tpmemu_files, 'qtest_aspeed.c'],
   'tpm-tis-device-swtpm-test': [io, tpmemu_files, 'tpm-tis-util.c'],
   'tpm-tis-device-test': [io, tpmemu_files, 'tpm-tis-util.c'],
+  'virtio-net-failover': files('migration-helpers.c'),
   'vmgenid-test': files('boot-sector.c', 'acpi-utils.c'),
   'netdev-socket': files('netdev-socket.c', '../unit/socket-helpers.c'),
 }

tests/qtest/migration-helpers.c

@@ -49,6 +49,26 @@ bool migrate_watch_for_resume(QTestState *who, const char *name,
     return false;
 }
 
+void migrate_qmp_fail(QTestState *who, const char *uri, const char *fmt, ...)
+{
+    va_list ap;
+    QDict *args, *err;
+
+    va_start(ap, fmt);
+    args = qdict_from_vjsonf_nofail(fmt, ap);
+    va_end(ap);
+
+    g_assert(!qdict_haskey(args, "uri"));
+    qdict_put_str(args, "uri", uri);
+
+    err = qtest_qmp_assert_failure_ref(
+        who, "{ 'execute': 'migrate', 'arguments': %p}", args);
+
+    g_assert(qdict_haskey(err, "desc"));
+
+    qobject_unref(err);
+}
+
 /*
  * Send QMP command "migrate".
  * Arguments are built from @fmt... (formatted like
@@ -70,6 +90,46 @@ void migrate_qmp(QTestState *who, const char *uri, const char *fmt, ...)
                              "{ 'execute': 'migrate', 'arguments': %p}", args);
 }
 
+void migrate_set_capability(QTestState *who, const char *capability,
+                            bool value)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-set-capabilities',"
+                             "'arguments': { "
+                             "'capabilities': [ { "
+                             "'capability': %s, 'state': %i } ] } }",
+                             capability, value);
+}
+
+void migrate_incoming_qmp(QTestState *to, const char *uri, const char *fmt, ...)
+{
+    va_list ap;
+    QDict *args, *rsp, *data;
+
+    va_start(ap, fmt);
+    args = qdict_from_vjsonf_nofail(fmt, ap);
+    va_end(ap);
+
+    g_assert(!qdict_haskey(args, "uri"));
+    qdict_put_str(args, "uri", uri);
+
+    migrate_set_capability(to, "events", true);
+
+    rsp = qtest_qmp(to, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
+                    args);
+    g_assert(qdict_haskey(rsp, "return"));
+    qobject_unref(rsp);
+
+    rsp = qtest_qmp_eventwait_ref(to, "MIGRATION");
+    g_assert(qdict_haskey(rsp, "data"));
+
+    data = qdict_get_qdict(rsp, "data");
+    g_assert(qdict_haskey(data, "status"));
+    g_assert_cmpstr(qdict_get_str(data, "status"), ==, "setup");
+
+    qobject_unref(rsp);
+}
+
 /*
  * Note: caller is responsible to free the returned object via
  * qobject_unref() after use

tests/qtest/migration-helpers.h

@@ -23,6 +23,16 @@ bool migrate_watch_for_resume(QTestState *who, const char *name,
 G_GNUC_PRINTF(3, 4)
 void migrate_qmp(QTestState *who, const char *uri, const char *fmt, ...);
 
+G_GNUC_PRINTF(3, 4)
+void migrate_incoming_qmp(QTestState *who, const char *uri,
+                          const char *fmt, ...);
+
+G_GNUC_PRINTF(3, 4)
+void migrate_qmp_fail(QTestState *who, const char *uri, const char *fmt, ...);
+
+void migrate_set_capability(QTestState *who, const char *capability,
+                            bool value);
+
 QDict *migrate_query(QTestState *who);
 QDict *migrate_query_not_failed(QTestState *who);
 

tests/qtest/migration-test.c

@@ -605,17 +605,6 @@ static void migrate_cancel(QTestState *who)
     qtest_qmp_assert_success(who, "{ 'execute': 'migrate_cancel' }");
 }
 
-static void migrate_set_capability(QTestState *who, const char *capability,
-                                   bool value)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-set-capabilities',"
-                             "'arguments': { "
-                             "'capabilities': [ { "
-                             "'capability': %s, 'state': %i } ] } }",
-                             capability, value);
-}
-
 static void migrate_postcopy_start(QTestState *from, QTestState *to)
 {
     qtest_qmp_assert_success(from, "{ 'execute': 'migrate-start-postcopy' }");
@@ -708,6 +697,8 @@ typedef struct {
         MIG_TEST_FAIL,
         /* This test should fail, dest qemu should fail with abnormal status */
         MIG_TEST_FAIL_DEST_QUIT_ERR,
+        /* The QMP command for this migration should fail with an error */
+        MIG_TEST_QMP_ERROR,
     } result;
 
     /*
@@ -1514,6 +1505,7 @@ static void test_precopy_common(MigrateCommon *args)
 {
     QTestState *from, *to;
     void *data_hook = NULL;
+    g_autofree char *connect_uri = NULL;
 
     if (test_migrate_start(&from, &to, args->listen_uri, &args->start)) {
         return;
@@ -1548,13 +1540,17 @@ static void test_precopy_common(MigrateCommon *args)
     }
 
     if (!args->connect_uri) {
-        g_autofree char *local_connect_uri =
-            migrate_get_socket_address(to, "socket-address");
-        migrate_qmp(from, local_connect_uri, "{}");
+        connect_uri = migrate_get_socket_address(to, "socket-address");
     } else {
-        migrate_qmp(from, args->connect_uri, "{}");
+        connect_uri = g_strdup(args->connect_uri);
+    }
+
+    if (args->result == MIG_TEST_QMP_ERROR) {
+        migrate_qmp_fail(from, connect_uri, "{}");
+        goto finish;
     }
 
+    migrate_qmp(from, connect_uri, "{}");
 
     if (args->result != MIG_TEST_SUCCEED) {
         bool allow_active = args->result == MIG_TEST_FAIL;
@@ -1606,6 +1602,7 @@ static void test_precopy_common(MigrateCommon *args)
         wait_for_serial("dest_serial");
     }
 
+finish:
     if (args->finish_hook) {
         args->finish_hook(from, to, data_hook);
     }
@@ -1981,8 +1978,7 @@ static void *test_migrate_fd_start_hook(QTestState *from,
     close(pair[0]);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'fd:fd-mig' }}");
+    migrate_incoming_qmp(to, "fd:fd-mig", "{}");
 
     /* Send the 2nd socket to the target */
     qtest_qmp_fds_assert_success(from, &pair[1], 1,
@@ -2204,8 +2200,7 @@ test_migrate_precopy_tcp_multifd_start_common(QTestState *from,
     migrate_set_capability(to, "multifd", true);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'tcp:127.0.0.1:0' }}");
+    migrate_incoming_qmp(to, "tcp:127.0.0.1:0", "{}");
 
     return NULL;
 }
@@ -2458,8 +2453,7 @@ static void test_multifd_tcp_cancel(void)
     migrate_set_capability(to, "multifd", true);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'tcp:127.0.0.1:0' }}");
+    migrate_incoming_qmp(to, "tcp:127.0.0.1:0", "{}");
 
     /* Wait for the first serial output from the source */
     wait_for_serial("src_serial");
@@ -2489,8 +2483,7 @@ static void test_multifd_tcp_cancel(void)
     migrate_set_capability(to2, "multifd", true);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to2, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'tcp:127.0.0.1:0' }}");
+    migrate_incoming_qmp(to2, "tcp:127.0.0.1:0", "{}");
 
     g_free(uri);
     uri = migrate_get_socket_address(to2, "socket-address");

tests/qtest/virtio-net-failover.c

@@ -11,6 +11,7 @@
 #include "libqtest.h"
 #include "libqos/pci.h"
 #include "libqos/pci-pc.h"
+#include "migration-helpers.h"
 #include "qapi/qmp/qdict.h"
 #include "qapi/qmp/qlist.h"
 #include "qapi/qmp/qjson.h"
@@ -736,26 +737,10 @@ static void test_migrate_out(gconstpointer opaque)
     machine_stop(qts);
 }
 
-static QDict *get_migration_event(QTestState *qts)
-{
-    QDict *resp;
-    QDict *data;
-
-    resp = qtest_qmp_eventwait_ref(qts, "MIGRATION");
-    g_assert(qdict_haskey(resp, "data"));
-
-    data = qdict_get_qdict(resp, "data");
-    g_assert(qdict_haskey(data, "status"));
-    qobject_ref(data);
-    qobject_unref(resp);
-
-    return data;
-}
-
 static void test_migrate_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *resp, *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -787,18 +772,7 @@ static void test_migrate_in(gconstpointer opaque)
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, false, "primary0", MAC_PRIMARY0);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     resp = get_failover_negociated_event(qts);
     g_assert_cmpstr(qdict_get_str(resp, "device-id"), ==, "standby0");
@@ -888,7 +862,7 @@ static void test_off_migrate_out(gconstpointer opaque)
 static void test_off_migrate_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -920,18 +894,7 @@ static void test_off_migrate_in(gconstpointer opaque)
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, true, "primary0", MAC_PRIMARY0);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, true, "primary0", MAC_PRIMARY0);
@@ -1026,7 +989,7 @@ static void test_guest_off_migrate_out(gconstpointer opaque)
 static void test_guest_off_migrate_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -1058,18 +1021,7 @@ static void test_guest_off_migrate_in(gconstpointer opaque)
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, false, "primary0", MAC_PRIMARY0);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, false, "primary0", MAC_PRIMARY0);
@@ -1728,7 +1680,7 @@ static void test_multi_out(gconstpointer opaque)
 static void test_multi_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *resp, *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -1794,18 +1746,7 @@ static void test_multi_in(gconstpointer opaque)
     check_one_card(qts, true, "standby1", MAC_STANDBY1);
     check_one_card(qts, false, "primary1", MAC_PRIMARY1);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     resp = get_failover_negociated_event(qts);
     g_assert_cmpstr(qdict_get_str(resp, "device-id"), ==, "standby0");