* [PATCH 0/3] Support chain migration in test
@ 2026-07-09 13:00 phind.uet
2026-07-09 13:00 ` [PATCH 1/3] tests/migration: Factor out per-process launch and setup helpers phind.uet
` (3 more replies)
0 siblings, 4 replies; 6+ messages in thread
From: phind.uet @ 2026-07-09 13:00 UTC (permalink / raw)
To: Laurent Vivier, Paolo Bonzini, Lukas Straub, Peter Xu,
Maciej S. Szmigiero, Mark Kanda, Ben Chaney
Cc: Nguyen Dinh Phi, qemu-devel
From: Nguyen Dinh Phi <phind.uet@gmail.com>
This series adds test infrastructure and test cases for multi-hop chain
migration, where a VM migrates from host A to B and then from B to C.
The migration test TODO list mentions ping-pong migration (A→B→A) as a
desirable scenario; the true ping-pong (A→B→A) would require the original
source A to become a destination for the return leg.
This is not possible: a QEMU process launched without -incoming cannot
later accept an incoming migration stream. Instead, this series implements
chain migration (A→B→C): B was already launched with -incoming and can
be re-wired as the source for the next hop, while a fresh QEMU instance C
is started as the new destination.
Nguyen Dinh Phi (3):
tests/migration: Factor out per-process launch and setup helpers
tests/migration: Retrieve serial path from QTestState
tests/migration: Add chain (A to B to C) precopy migration tests
tests/qtest/libqtest.c | 16 +
tests/qtest/libqtest.h | 8 +
tests/qtest/migration/colo-tests.c | 14 +-
tests/qtest/migration/cpr-tests.c | 8 +-
tests/qtest/migration/framework.c | 475 ++++++++++++++++----------
tests/qtest/migration/framework.h | 21 +-
tests/qtest/migration/misc-tests.c | 4 +-
tests/qtest/migration/precopy-tests.c | 51 ++-
8 files changed, 389 insertions(+), 208 deletions(-)
--
2.50.1 (Apple Git-155)
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/3] tests/migration: Factor out per-process launch and setup helpers
2026-07-09 13:00 [PATCH 0/3] Support chain migration in test phind.uet
@ 2026-07-09 13:00 ` phind.uet
2026-08-20 15:13 ` Fabiano Rosas
2026-07-09 13:00 ` [PATCH 2/3] tests/migration: Retrieve serial path from QTestState phind.uet
` (2 subsequent siblings)
3 siblings, 1 reply; 6+ messages in thread
From: phind.uet @ 2026-07-09 13:00 UTC (permalink / raw)
To: Peter Xu, Fabiano Rosas, Laurent Vivier, Paolo Bonzini
Cc: Nguyen Dinh Phi, qemu-devel
From: Nguyen Dinh Phi <phind.uet@gmail.com>
migrate_start() always spawned source and destination together, and
migrate_start_set_capabilities() required both QTestState pointers at
once. This coupling prevents launching a third QEMU instance or
re-configuring an existing destination as a new source.
Split the logic into three public helpers:
migrate_launch_source() / migrate_launch_dest()
Spawn a single QEMU process and record its serial file path on
the returned QTestState.
migrate_setup_instance()
Register the event callback and apply migration capabilities to
one already-running process. Can be called again to re-wire the
same process for a different role.
migrate_start() is kept for backward compatibility and now delegates
to these helpers internally.
Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com>
---
tests/qtest/migration/framework.c | 253 +++++++++++++++++-------------
tests/qtest/migration/framework.h | 18 ++-
2 files changed, 165 insertions(+), 106 deletions(-)
diff --git a/tests/qtest/migration/framework.c b/tests/qtest/migration/framework.c
index a830b96f41..305b8968ff 100644
--- a/tests/qtest/migration/framework.c
+++ b/tests/qtest/migration/framework.c
@@ -208,9 +208,11 @@ static QList *migrate_start_get_qmp_capabilities(const MigrateStart *args)
return capabilities;
}
-static void migrate_start_set_capabilities(QTestState *from, QTestState *to,
- MigrateStart *args)
+void migrate_setup_instance(QTestState *who, QTestMigrationState *state,
+ MigrateStart *args)
{
+ qtest_qmp_set_event_callback(who, migrate_watch_for_events, state);
+ *state = (QTestMigrationState) { .suspend_me = args->suspend_me };
/*
* MigrationCapability_lookup and MIGRATION_CAPABILITY_ constants
* are from qapi-types-migration.h.
@@ -220,25 +222,13 @@ static void migrate_start_set_capabilities(QTestState *from, QTestState *to,
* Enable return path first, since other features depend on it.
*/
if (args->caps[MIGRATION_CAPABILITY_RETURN_PATH]) {
- if (from) {
- migrate_set_capability(from, "return-path", true);
- }
- if (to) {
- migrate_set_capability(to, "return-path", true);
- }
+ migrate_set_capability(who, "return-path", true);
}
for (uint8_t i = 0; i < MIGRATION_CAPABILITY__MAX; i++) {
- if (!args->caps[i]) {
- continue;
- }
- if (from) {
- migrate_set_capability(from,
- MigrationCapability_lookup.array[i], true);
- }
- if (to) {
- migrate_set_capability(to,
- MigrationCapability_lookup.array[i], true);
+ if (args->caps[i]) {
+ migrate_set_capability(who, MigrationCapability_lookup.array[i],
+ true);
}
}
@@ -246,26 +236,17 @@ static void migrate_start_set_capabilities(QTestState *from, QTestState *to,
* Always enable migration events. Libvirt always uses it, let's try
* to mimic as closer as that.
*/
- migrate_set_capability(from, "events", true);
- if (!args->defer_target_connect && to) {
- migrate_set_capability(to, "events", true);
- }
+ migrate_set_capability(who, "events", true);
- /*
+ /*
* Default number of channels should be fine for most
* tests. Individual tests can override by calling
* migrate_set_parameter() directly.
*/
if (args->caps[MIGRATION_CAPABILITY_MULTIFD]) {
- migrate_set_parameter_int(from, "multifd-channels",
+ migrate_set_parameter_int(who, "multifd-channels",
MULTIFD_TEST_CHANNELS);
- if (to) {
- migrate_set_parameter_int(to, "multifd-channels",
- MULTIFD_TEST_CHANNELS);
- }
}
-
- return;
}
static char *test_shmem_path(void)
@@ -308,12 +289,28 @@ static char *migrate_mem_type_get_opts(MemType type, const char *memory_size)
return opts;
}
-int migrate_args(char **from, char **to, MigrateStart *args)
+/*
+ * Build a QEMU command line for one migration participant.
+ *
+ * @serial_name : serial output file basename under tmpfs
+ * @is_target : set to true if the new qemu process is destination side
+ * @extra_opts : extra arguments
+ * @defer_events : when true and is_target is set, use the command-line
+ * event flag instead of the QMP capability (for deferred
+ * monitor connections)
+ * @args : common process settings
+ *
+ * Returns 0 and sets *cmd_out on success. Returns -1 and calls
+ * g_test_skip() if the machine type is not available.
+ */
+static int migrate_build_cmd(const char *serial_name,
+ bool is_target,
+ const char *extra_opts,
+ bool defer_events,
+ MigrateStart *args,
+ char **cmd_out)
{
- /* options for source and target */
g_autofree gchar *arch_opts = NULL;
- gchar *cmd_source = NULL;
- gchar *cmd_target = NULL;
const gchar *ignore_stderr;
g_autofree char *mem_object = NULL;
const char *kvm_opts = NULL;
@@ -323,16 +320,10 @@ int migrate_args(char **from, char **to, MigrateStart *args)
g_autofree char *machine = NULL;
const char *bootpath = bootfile_get();
g_autofree char *memory_backend = NULL;
- const char *events;
if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
memory_size = "150M";
-
- if (g_str_equal(arch, "i386")) {
- machine_alias = "pc";
- } else {
- machine_alias = "q35";
- }
+ machine_alias = g_str_equal(arch, "i386") ? "pc" : "q35";
arch_opts = g_strdup_printf(
"-drive if=none,id=d0,file=%s,format=raw "
"-device ide-hd,drive=d0,secs=1,cyls=1,heads=1", bootpath);
@@ -346,13 +337,13 @@ int migrate_args(char **from, char **to, MigrateStart *args)
end_address = S390_TEST_MEM_END;
} else if (strcmp(arch, "ppc64") == 0) {
memory_size = "256M";
- start_address = PPC_TEST_MEM_START;
- end_address = PPC_TEST_MEM_END;
machine_alias = "pseries";
machine_opts = "vsmt=8";
arch_opts = g_strdup_printf(
"-nodefaults -machine " PSERIES_DEFAULT_CAPABILITIES " "
"-bios %s", bootpath);
+ start_address = PPC_TEST_MEM_START;
+ end_address = PPC_TEST_MEM_END;
} else if (strcmp(arch, "aarch64") == 0) {
memory_size = "150M";
machine_alias = "virt";
@@ -394,53 +385,103 @@ int migrate_args(char **from, char **to, MigrateStart *args)
}
if (!qtest_has_machine(machine_alias)) {
- g_autofree char *msg = g_strdup_printf("machine %s not supported", machine_alias);
+ g_autofree char *msg = g_strdup_printf("machine %s not supported",
+ machine_alias);
g_test_skip(msg);
return -1;
}
machine = resolve_machine_version(machine_alias, QEMU_ENV_SRC,
QEMU_ENV_DST);
-
g_test_message("Using machine type: %s", machine);
- cmd_source = g_strdup_printf("-accel kvm%s -accel tcg "
- "-machine %s,%s "
- "-name source,debug-threads=on "
- "%s "
- "-serial file:%s/src_serial "
- "%s %s %s",
- kvm_opts ? kvm_opts : "",
- machine, machine_opts,
- memory_backend, tmpfs,
- arch_opts ? arch_opts : "",
- args->opts_source ? args->opts_source : "",
- ignore_stderr);
+ if (is_target) {
+ /*
+ * If the monitor connection is deferred, enable events on the command
+ * line so none are missed. This is for testing only, do not set
+ * migration options like this in general.
+ */
+ const char *events = defer_events ? "-global migration.x-events=on"
+ : "";
+ *cmd_out = g_strdup_printf(
+ "-accel kvm%s -accel tcg "
+ "-machine %s,%s "
+ "-name target,debug-threads=on "
+ "%s "
+ "-serial file:%s/%s "
+ "-incoming defer "
+ "%s %s %s %s",
+ kvm_opts ? kvm_opts : "",
+ machine, machine_opts,
+ memory_backend, tmpfs, serial_name,
+ events,
+ arch_opts ? arch_opts : "",
+ extra_opts ? extra_opts : "",
+ ignore_stderr);
+ } else {
+ *cmd_out = g_strdup_printf(
+ "-accel kvm%s -accel tcg "
+ "-machine %s,%s "
+ "-name source,debug-threads=on "
+ "%s "
+ "-serial file:%s/%s "
+ "%s %s %s",
+ kvm_opts ? kvm_opts : "",
+ machine, machine_opts,
+ memory_backend, tmpfs, serial_name,
+ arch_opts ? arch_opts : "",
+ extra_opts ? extra_opts : "",
+ ignore_stderr);
+ }
- /*
- * If the monitor connection is deferred, enable events on the command line
- * so none are missed. This is for testing only, do not set migration
- * options like this in general.
- */
- events = args->defer_target_connect ? "-global migration.x-events=on" : "";
-
- cmd_target = g_strdup_printf("-accel kvm%s -accel tcg "
- "-machine %s,%s "
- "-name target,debug-threads=on "
- "%s "
- "-serial file:%s/dest_serial "
- "-incoming defer "
- "%s %s %s %s",
- kvm_opts ? kvm_opts : "",
- machine, machine_opts,
- memory_backend, tmpfs,
- events,
- arch_opts ? arch_opts : "",
- args->opts_target ? args->opts_target : "",
- ignore_stderr);
-
- *from = cmd_source;
- *to = cmd_target;
+ return 0;
+}
+
+/*
+ * Launch a QEMU process as a migration source.
+ * Returns the QTestState on success, or NULL otherwise
+ */
+QTestState *migrate_launch_source(const char *serial_name, MigrateStart *args)
+{
+ g_autofree char *cmd = NULL;
+ g_autoptr(QList) capabilities = migrate_start_get_qmp_capabilities(args);
+
+ if (migrate_build_cmd(serial_name, false, args->opts_source,
+ false, args, &cmd)) {
+ return NULL;
+ }
+ return qtest_init_ext(QEMU_ENV_SRC, cmd, capabilities, true);
+}
+
+/*
+ * Launch a QEMU process as a migration destination.
+ * Returns the QTestState on success, or NULL otherwise
+ */
+QTestState *migrate_launch_dest(const char *serial_name, MigrateStart *args)
+{
+ g_autofree char *cmd = NULL;
+ g_autoptr(QList) capabilities = migrate_start_get_qmp_capabilities(args);
+
+ if (migrate_build_cmd(serial_name, true, args->opts_target,
+ args->defer_target_connect, args, &cmd)) {
+ return NULL;
+ }
+ return qtest_init_ext(QEMU_ENV_DST, cmd, capabilities,
+ !args->defer_target_connect);
+}
+
+int migrate_args(char **from, char **to, MigrateStart *args)
+{
+ if (migrate_build_cmd("src_serial", false, args->opts_source,
+ false, args, from)) {
+ return -1;
+ }
+ if (migrate_build_cmd("dest_serial", true, args->opts_target,
+ args->defer_target_connect, args, to)) {
+ g_free(*from);
+ *from = NULL;
+ return -1;
+ }
return 0;
}
@@ -482,43 +523,45 @@ static void migrate_mem_type_cleanup(MemType type)
int migrate_start(QTestState **from, QTestState **to, MigrateStart *args)
{
- g_autofree gchar *cmd_source = NULL;
- g_autofree gchar *cmd_target = NULL;
- g_autoptr(QList) capabilities = migrate_start_get_qmp_capabilities(args);
-
if (!migrate_mem_type_prepare(args->mem_type)) {
return -1;
}
- dst_state = (QTestMigrationState) { };
- src_state = (QTestMigrationState) { };
+ src_state = (QTestMigrationState){};
+ dst_state = (QTestMigrationState){};
bootfile_create(qtest_get_arch(), tmpfs, args->suspend_me);
- src_state.suspend_me = args->suspend_me;
-
- if (migrate_args(&cmd_source, &cmd_target, args)) {
- return -1;
- }
if (!args->only_target) {
- *from = qtest_init_ext(QEMU_ENV_SRC, cmd_source, capabilities, true);
- qtest_qmp_set_event_callback(*from,
- migrate_watch_for_events,
- &src_state);
+ *from = migrate_launch_source("src_serial", args);
+ if (!*from) {
+ return -1;
+ }
+ migrate_setup_instance(*from, &src_state, args);
}
if (!args->only_source) {
- *to = qtest_init_ext(QEMU_ENV_DST, cmd_target, capabilities,
- !args->defer_target_connect);
- qtest_qmp_set_event_callback(*to,
- migrate_watch_for_events,
- &dst_state);
+ *to = migrate_launch_dest("dest_serial", args);
+ if (!*to) {
+ if (!args->only_target) {
+ qtest_quit(*from);
+ }
+ return -1;
+ }
+ if (!args->defer_target_connect) {
+ migrate_setup_instance(*to, &dst_state, args);
+ } else {
+ /*
+ * The monitor is not connected yet; only register the event
+ * callback so no events are missed.
+ * The caller must call migrate_setup_instance() after
+ * qtest_connect() if it wants to setup any capability
+ */
+ qtest_qmp_set_event_callback(*to, migrate_watch_for_events,
+ &dst_state);
+ }
}
migrate_mem_type_cleanup(args->mem_type);
- migrate_start_set_capabilities(*from,
- args->only_source ? NULL : *to,
- args);
-
return 0;
}
diff --git a/tests/qtest/migration/framework.h b/tests/qtest/migration/framework.h
index 941cbd7102..f054ef8f4d 100644
--- a/tests/qtest/migration/framework.h
+++ b/tests/qtest/migration/framework.h
@@ -225,10 +225,27 @@ typedef struct {
bool live;
} MigrateCommon;
+typedef struct QTestMigrationState QTestMigrationState;
+
void wait_for_serial(const char *side);
void migrate_prepare_for_dirty_mem(QTestState *from);
void migrate_wait_for_dirty_mem(QTestState *from, QTestState *to);
+/*
+ * Start a QEMU process which has serial set to @serial_name
+ */
+QTestState *migrate_launch_source(const char *serial_name, MigrateStart *args);
+/*
+ * Start a QEMU process which has serial set to @serial_name
+ */
+QTestState *migrate_launch_dest(const char *serial_name, MigrateStart *args);
+/*
+ * Registers the event callback and sets migration capabilities on an
+ * already-running process
+ */
+void migrate_setup_instance(QTestState *who, QTestMigrationState *state,
+ MigrateStart *args);
+
int migrate_args(char **from, char **to, MigrateStart *args);
int migrate_start(QTestState **from, QTestState **to, MigrateStart *args);
void migrate_end(QTestState *from, QTestState *to, bool test_dest);
@@ -240,7 +257,6 @@ int test_precopy_common(MigrateCommon *args);
void test_precopy_unix_common(MigrateCommon *args);
void test_file_common(MigrateCommon *args, bool stop_src);
-typedef struct QTestMigrationState QTestMigrationState;
QTestMigrationState *get_src(void);
QTestMigrationState *get_dst(void);
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/3] tests/migration: Retrieve serial path from QTestState
2026-07-09 13:00 [PATCH 0/3] Support chain migration in test phind.uet
2026-07-09 13:00 ` [PATCH 1/3] tests/migration: Factor out per-process launch and setup helpers phind.uet
@ 2026-07-09 13:00 ` phind.uet
2026-07-09 13:00 ` [PATCH 3/3] tests/migration: Add chain (A to B to C) precopy migration tests phind.uet
2026-08-20 15:22 ` [PATCH 0/3] Support chain migration in test Fabiano Rosas
3 siblings, 0 replies; 6+ messages in thread
From: phind.uet @ 2026-07-09 13:00 UTC (permalink / raw)
To: Fabiano Rosas, Laurent Vivier, Paolo Bonzini, Lukas Straub,
Peter Xu, Maciej S. Szmigiero, Mark Kanda, Ben Chaney
Cc: Nguyen Dinh Phi, qemu-devel
From: Nguyen Dinh Phi <phind.uet@gmail.com>
Replace hard-coded side names ("src_serial", "dest_serial") passed to
wait_for_serial() with qtest_get_serial_path(). The path is stored on
the QTestState at launch time by migrate_launch_source/dest().
Hard-coded names break when a process changes role, for example when a
completed destination is re-used as a new source in a chain migration.
Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com>
---
tests/qtest/libqtest.c | 16 ++++++++++++
tests/qtest/libqtest.h | 8 ++++++
tests/qtest/migration/colo-tests.c | 14 +++++-----
tests/qtest/migration/cpr-tests.c | 8 +++---
tests/qtest/migration/framework.c | 37 ++++++++++++++++-----------
tests/qtest/migration/framework.h | 2 +-
tests/qtest/migration/misc-tests.c | 4 +--
tests/qtest/migration/precopy-tests.c | 28 +++++++++++---------
8 files changed, 76 insertions(+), 41 deletions(-)
diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
index c33c799c92..3fccd089dd 100644
--- a/tests/qtest/libqtest.c
+++ b/tests/qtest/libqtest.c
@@ -93,6 +93,7 @@ struct QTestState
GList *pending_events;
QTestQMPEventCallback eventCB;
void *eventData;
+ char *serial_path;
};
static GHookList abrt_hooks;
@@ -688,10 +689,25 @@ void qtest_quit(QTestState *s)
}
g_list_free(s->pending_events);
+ if (s->serial_path) {
+ unlink(s->serial_path);
+ g_free(s->serial_path);
+ }
g_free(s);
}
+void qtest_set_serial_path(QTestState *s, const char *path)
+{
+ g_free(s->serial_path);
+ s->serial_path = g_strdup(path);
+}
+
+const char *qtest_get_serial_path(QTestState *s)
+{
+ return s->serial_path;
+}
+
static void socket_send(int fd, const char *buf, size_t size)
{
ssize_t res = qemu_send_full(fd, buf, size);
diff --git a/tests/qtest/libqtest.h b/tests/qtest/libqtest.h
index 45217fb8dc..0958cf1662 100644
--- a/tests/qtest/libqtest.h
+++ b/tests/qtest/libqtest.h
@@ -98,6 +98,14 @@ QTestState *qtest_init(const char *extra_args);
QTestState *qtest_init_ext(const char *var, const char *extra_args,
QList *capabilities, bool do_connect);
+/**
+ * qtest_set_serial_path:
+ * @s: #QTestState instance
+ * @path: full path to the serial output file to unlink on qtest_quit()
+ */
+void qtest_set_serial_path(QTestState *s, const char *path);
+const char *qtest_get_serial_path(QTestState *s);
+
/**
* qtest_init_without_qmp_handshake:
* @extra_args: other arguments to pass to QEMU. CAUTION: these
diff --git a/tests/qtest/migration/colo-tests.c b/tests/qtest/migration/colo-tests.c
index f7f9ba491b..c6b6faa578 100644
--- a/tests/qtest/migration/colo-tests.c
+++ b/tests/qtest/migration/colo-tests.c
@@ -58,21 +58,21 @@ static int test_colo_common(MigrateCommon *args,
migrate_incoming_qmp(to, args->uri, NULL, "{}");
migrate_ensure_converge(from);
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_qmp(from, to, NULL, NULL, "{}");
wait_for_migration_status(from, "colo", NULL);
wait_for_resume(to, get_dst());
- wait_for_serial("src_serial");
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(from));
+ wait_for_serial(qtest_get_serial_path(to));
/* wait for 3 checkpoints */
for (int i = 0; i < 3; i++) {
qtest_qmp_eventwait(to, "RESUME");
- wait_for_serial("src_serial");
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(from));
+ wait_for_serial(qtest_get_serial_path(to));
}
if (failover_during_checkpoint) {
@@ -83,13 +83,13 @@ static int test_colo_common(MigrateCommon *args,
"'arguments': {'instances':"
"[{'type': 'migration'}]}}");
qtest_qmp_assert_success(from, "{'execute': 'x-colo-lost-heartbeat'}");
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
} else {
qtest_qmp_assert_success(to, "{'exec-oob': 'yank', 'id': 'yank-cmd', "
"'arguments': {'instances':"
"[{'type': 'migration'}]}}");
qtest_qmp_assert_success(to, "{'execute': 'x-colo-lost-heartbeat'}");
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to));
}
if (args->end_hook) {
diff --git a/tests/qtest/migration/cpr-tests.c b/tests/qtest/migration/cpr-tests.c
index 0bec753b4a..f56bbe48fe 100644
--- a/tests/qtest/migration/cpr-tests.c
+++ b/tests/qtest/migration/cpr-tests.c
@@ -66,7 +66,7 @@ static int test_transfer(MigrateCommon *args, const char *cpr_channel,
migrate_set_parameter_str(from, "mode", "cpr-transfer");
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
qtest_qmp_assert_success(from, "{ 'execute' : 'stop'}");
wait_for_stop(from, get_src());
@@ -89,7 +89,7 @@ static int test_transfer(MigrateCommon *args, const char *cpr_channel,
qtest_qmp_assert_success(to, "{ 'execute' : 'cont'}");
wait_for_resume(to, get_dst());
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to));
migrate_end(from, to, true);
@@ -241,7 +241,7 @@ static void test_cpr_exec(MigrateCommon *args)
data_hook = args->start_hook(from, NULL);
}
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
set_cpr_exec_args(from, args);
migrate_set_capability(from, "events", true);
migrate_qmp(from, NULL, connect_uri, NULL, "{}");
@@ -260,7 +260,7 @@ static void test_cpr_exec(MigrateCommon *args)
wait_for_resume(to, get_dst());
/* Device on target is still named src_serial because args do not change */
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
if (args->end_hook) {
args->end_hook(from, to, data_hook);
diff --git a/tests/qtest/migration/framework.c b/tests/qtest/migration/framework.c
index 305b8968ff..a7dffeb82c 100644
--- a/tests/qtest/migration/framework.c
+++ b/tests/qtest/migration/framework.c
@@ -58,10 +58,9 @@ static char *tmpfs;
* we get an 'A' followed by an endless string of 'B's
* but on the destination we won't have the A (unless we enabled suspend/resume)
*/
-void wait_for_serial(const char *side)
+void wait_for_serial(const char *path)
{
- g_autofree char *serialpath = g_strdup_printf("%s/%s", tmpfs, side);
- FILE *serialfile = fopen(serialpath, "r");
+ FILE *serialfile = fopen(path, "r");
do {
int readvalue = fgetc(serialfile);
@@ -82,7 +81,7 @@ void wait_for_serial(const char *side)
break;
default:
- fprintf(stderr, "Unexpected %d on %s serial\n", readvalue, side);
+ fprintf(stderr, "Unexpected %d on %s serial\n", readvalue, path);
g_assert_not_reached();
}
} while (true);
@@ -450,7 +449,12 @@ QTestState *migrate_launch_source(const char *serial_name, MigrateStart *args)
false, args, &cmd)) {
return NULL;
}
- return qtest_init_ext(QEMU_ENV_SRC, cmd, capabilities, true);
+ QTestState *s = qtest_init_ext(QEMU_ENV_SRC, cmd, capabilities, true);
+ if (s) {
+ g_autofree char *path = g_strdup_printf("%s/%s", tmpfs, serial_name);
+ qtest_set_serial_path(s, path);
+ }
+ return s;
}
/*
@@ -466,8 +470,13 @@ QTestState *migrate_launch_dest(const char *serial_name, MigrateStart *args)
args->defer_target_connect, args, &cmd)) {
return NULL;
}
- return qtest_init_ext(QEMU_ENV_DST, cmd, capabilities,
- !args->defer_target_connect);
+ QTestState *s = qtest_init_ext(QEMU_ENV_DST, cmd, capabilities,
+ !args->defer_target_connect);
+ if (s) {
+ g_autofree char *path = g_strdup_printf("%s/%s", tmpfs, serial_name);
+ qtest_set_serial_path(s, path);
+ }
+ return s;
}
int migrate_args(char **from, char **to, MigrateStart *args)
@@ -595,8 +604,6 @@ void migrate_end(QTestState *from, QTestState *to, bool test_dest)
cleanup("migsocket");
cleanup("cpr.sock");
- cleanup("src_serial");
- cleanup("dest_serial");
cleanup(FILE_TEST_FILENAME);
}
@@ -631,7 +638,7 @@ static int migrate_postcopy_prepare(QTestState **from_ptr,
" 'port': '0' } } ] } }");
/* Wait for the first serial output from the source */
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
wait_for_suspend(from, &src_state);
migrate_qmp(from, to, NULL, NULL, "{}");
@@ -657,7 +664,7 @@ static void migrate_postcopy_complete(QTestState *from, QTestState *to,
}
/* Make sure we get at least one "B" on destination */
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to));
if (env->uffd_feature_thread_id) {
read_blocktime(to);
@@ -895,7 +902,7 @@ int test_precopy_common(MigrateCommon *args)
/* Wait for the first serial output from the source */
if (args->result == MIG_TEST_SUCCEED) {
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
wait_for_suspend(from, &src_state);
}
@@ -972,7 +979,7 @@ int test_precopy_common(MigrateCommon *args)
qtest_qmp_assert_success(to, "{'execute': 'system_wakeup'}");
}
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to));
}
finish:
@@ -1063,7 +1070,7 @@ void test_file_common(MigrateCommon *args, bool stop_src)
}
migrate_ensure_converge(from);
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
if (stop_src) {
qtest_qmp_assert_success(from, "{ 'execute' : 'stop'}");
@@ -1090,7 +1097,7 @@ void test_file_common(MigrateCommon *args, bool stop_src)
}
wait_for_resume(to, &dst_state);
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to));
if (check_offset) {
file_check_offset_region();
diff --git a/tests/qtest/migration/framework.h b/tests/qtest/migration/framework.h
index f054ef8f4d..f6936eb8c6 100644
--- a/tests/qtest/migration/framework.h
+++ b/tests/qtest/migration/framework.h
@@ -227,7 +227,7 @@ typedef struct {
typedef struct QTestMigrationState QTestMigrationState;
-void wait_for_serial(const char *side);
+void wait_for_serial(const char *path);
void migrate_prepare_for_dirty_mem(QTestState *from);
void migrate_wait_for_dirty_mem(QTestState *from, QTestState *to);
diff --git a/tests/qtest/migration/misc-tests.c b/tests/qtest/migration/misc-tests.c
index ec6d438cdc..73750335f1 100644
--- a/tests/qtest/migration/misc-tests.c
+++ b/tests/qtest/migration/misc-tests.c
@@ -128,7 +128,7 @@ static void do_test_validate_uuid(MigrateStart *args, bool should_fail)
migrate_set_capability(from, "validate-uuid", true);
/* Wait for the first serial output from the source */
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_incoming_qmp(to, uri, NULL, "{}");
migrate_qmp(from, to, uri, NULL, "{}");
@@ -185,7 +185,7 @@ static void do_test_validate_uri_channel(MigrateCommon *args)
}
/* Wait for the first serial output from the source */
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_incoming_qmp(to, "tcp:127.0.0.1:0", NULL, "{}");
diff --git a/tests/qtest/migration/precopy-tests.c b/tests/qtest/migration/precopy-tests.c
index a23d51126b..194462c841 100644
--- a/tests/qtest/migration/precopy-tests.c
+++ b/tests/qtest/migration/precopy-tests.c
@@ -282,7 +282,8 @@ static void test_auto_converge(char *name, MigrateCommon *args)
/* To check remaining size after precopy */
migrate_set_capability(from, "pause-before-switchover", true);
- wait_for_serial("src_serial");
+ /* Wait for the first serial output from the source */
+ wait_for_serial(qtest_get_serial_path(from));
migrate_incoming_qmp(to, uri, NULL, "{}");
migrate_qmp(from, to, uri, NULL, "{}");
@@ -317,7 +318,7 @@ static void test_auto_converge(char *name, MigrateCommon *args)
qtest_qmp_eventwait(to, "RESUME");
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to));
wait_for_migration_complete(from);
migrate_end(from, to, true);
@@ -436,7 +437,7 @@ static void test_multifd_tcp_cancel(MigrateCommon *args, bool postcopy_ram)
migrate_incoming_qmp(to, "tcp:127.0.0.1:0", NULL, "{}");
/* Wait for the first serial output from the source */
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_qmp(from, to, NULL, NULL, "{}");
@@ -486,7 +487,7 @@ static void test_multifd_tcp_cancel(MigrateCommon *args, bool postcopy_ram)
wait_for_stop(from, get_src());
qtest_qmp_eventwait(to2, "RESUME");
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to2));
wait_for_migration_complete(from);
migrate_end(from, to2, true);
}
@@ -510,7 +511,7 @@ static void test_cancel_src_after_failed(QTestState *from, QTestState *to,
* failed state during migrate_qmp().
*/
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_ensure_converge(from);
migrate_qmp(from, to, uri, NULL, "{}");
@@ -535,7 +536,7 @@ static void test_cancel_src_after_cancelled(QTestState *from, QTestState *to,
{
migrate_incoming_qmp(to, uri, NULL, "{}");
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_ensure_converge(from);
migrate_qmp(from, to, uri, NULL, "{}");
@@ -560,7 +561,7 @@ static void test_cancel_src_after_complete(QTestState *from, QTestState *to,
{
migrate_incoming_qmp(to, uri, NULL, "{}");
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_ensure_converge(from);
migrate_qmp(from, to, uri, NULL, "{}");
@@ -586,7 +587,7 @@ static void test_cancel_src_after_none(QTestState *from, QTestState *to,
*/
migrate_cancel(to);
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_cancel(from);
migrate_incoming_qmp(to, uri, NULL, "{}");
@@ -610,7 +611,7 @@ static void test_cancel_src_pre_switchover(QTestState *from, QTestState *to,
migrate_incoming_qmp(to, uri, NULL, "{}");
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
migrate_ensure_converge(from);
migrate_qmp(from, to, uri, NULL, "{}");
@@ -831,7 +832,10 @@ static void test_vcpu_dirty_limit(char *name, MigrateCommon *args)
vm = dirtylimit_start_vm();
/* Wait for the first serial output from the vm*/
- wait_for_serial("vm_serial");
+ {
+ g_autofree char *vm_serial = g_strdup_printf("%s/vm_serial", tmpfs);
+ wait_for_serial(vm_serial);
+ }
/* Do dirtyrate measurement with calc time equals 1s */
calc_dirty_rate(vm, 1);
@@ -924,7 +928,7 @@ static void migrate_dirty_limit_wait_showup(QTestState *from,
migrate_set_capability(from, "pause-before-switchover", true);
/* Wait for the serial output from the source */
- wait_for_serial("src_serial");
+ wait_for_serial(qtest_get_serial_path(from));
}
/*
@@ -1062,7 +1066,7 @@ static void test_dirty_limit(char *name, MigrateCommon *args)
qtest_qmp_eventwait(to, "RESUME");
- wait_for_serial("dest_serial");
+ wait_for_serial(qtest_get_serial_path(to));
wait_for_migration_complete(from);
migrate_end(from, to, true);
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 3/3] tests/migration: Add chain (A to B to C) precopy migration tests
2026-07-09 13:00 [PATCH 0/3] Support chain migration in test phind.uet
2026-07-09 13:00 ` [PATCH 1/3] tests/migration: Factor out per-process launch and setup helpers phind.uet
2026-07-09 13:00 ` [PATCH 2/3] tests/migration: Retrieve serial path from QTestState phind.uet
@ 2026-07-09 13:00 ` phind.uet
2026-08-20 15:22 ` [PATCH 0/3] Support chain migration in test Fabiano Rosas
3 siblings, 0 replies; 6+ messages in thread
From: phind.uet @ 2026-07-09 13:00 UTC (permalink / raw)
To: Peter Xu, Fabiano Rosas, Laurent Vivier, Paolo Bonzini
Cc: Nguyen Dinh Phi, qemu-devel
From: Nguyen Dinh Phi <phind.uet@gmail.com>
Extract migrate_precopy_hop() from the SUCCESS path of test_precopy_common()
to wrap the per-hop migration sequence of a succesfull migration.
test_precopy_common() delegates its success path to this helper; failure
paths are handled directly.
Introduce test_precopy_chain(), a helper that drives two consecutive
migration hops on already-running processes: first A→B, then B→C, both
hops are expected to be success.
Add two test cases exercising the new helper:
- /migration/precopy/tcp/plain/chain
- /migration/multifd/tcp/channels/plain/chain
Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com>
---
tests/qtest/migration/framework.c | 195 +++++++++++++++++---------
tests/qtest/migration/framework.h | 1 +
tests/qtest/migration/precopy-tests.c | 23 +++
3 files changed, 153 insertions(+), 66 deletions(-)
diff --git a/tests/qtest/migration/framework.c b/tests/qtest/migration/framework.c
index a7dffeb82c..b4218b2f23 100644
--- a/tests/qtest/migration/framework.c
+++ b/tests/qtest/migration/framework.c
@@ -883,28 +883,25 @@ void test_postcopy_recovery_common(MigrateCommon *args,
migrate_postcopy_complete(from, to, hook_data, args);
}
-int test_precopy_common(MigrateCommon *args)
+/*
+ * Perform one precopy migration hop on an already-running (from, to) pair.
+ * Both processes must have migrate_setup_instance() called before this
+ * function.
+ * Always expects the hop to succeed.
+ *
+ */
+static void migrate_precopy_hop(QTestState *from, QTestState *to,
+ const char *listen_uri,
+ const char *connect_uri,
+ MigrateCommon *args)
{
- QTestState *from, *to;
- void *data_hook = NULL;
QObject *channels = NULL;
- const char *listen_uri = args->uri ?: "tcp:127.0.0.1:0";
-
- if (migrate_start(&from, &to, &args->start)) {
- return -1;
- }
-
- if (args->start_hook) {
- data_hook = args->start_hook(from, to);
- }
+ int iters;
migrate_incoming_qmp(to, listen_uri, NULL, "{}");
- /* Wait for the first serial output from the source */
- if (args->result == MIG_TEST_SUCCEED) {
- wait_for_serial(qtest_get_serial_path(from));
- wait_for_suspend(from, &src_state);
- }
+ wait_for_serial(qtest_get_serial_path(from));
+ wait_for_suspend(from, &src_state);
if (args->live) {
migrate_ensure_non_converge(from);
@@ -913,76 +910,104 @@ int test_precopy_common(MigrateCommon *args)
/*
* Testing non-live migration, we allow it to run at
* full speed to ensure short test case duration.
- * For tests expected to fail, we don't need to
- * change anything.
*/
- if (args->result == MIG_TEST_SUCCEED) {
- qtest_qmp_assert_success(from, "{ 'execute' : 'stop'}");
- wait_for_stop(from, &src_state);
- migrate_ensure_converge(from);
- }
+ qtest_qmp_assert_success(from, "{ 'execute' : 'stop'}");
+ wait_for_stop(from, &src_state);
+ migrate_ensure_converge(from);
}
if (args->connect_channels) {
channels = qobject_from_json(args->connect_channels, &error_abort);
}
- if (args->result == MIG_TEST_QMP_ERROR) {
- migrate_qmp_fail(from, args->uri, channels, "{}");
- goto finish;
- }
+ migrate_qmp(from, to, connect_uri, channels, "{}");
- migrate_qmp(from, to, args->uri, channels, "{}");
+ if (args->live) {
+ /*
+ * For initial iteration(s) we must do a full pass,
+ * but for the final iteration, we need only wait
+ * for some dirty mem before switching to converge.
+ */
+ /*
+ * Avoid changing the args->iterations by using a local copy
+ */
+ iters = args->iterations;
+ while (iters > 1) {
+ wait_for_migration_pass(from, &src_state);
+ iters--;
+ }
+ migrate_wait_for_dirty_mem(from, to);
+
+ migrate_ensure_converge(from);
+
+ /*
+ * We do this first, as it has a timeout to stop us
+ * hanging forever if migration didn't converge
+ */
+ wait_for_migration_complete(from);
+
+ wait_for_stop(from, &src_state);
- if (args->result != MIG_TEST_SUCCEED) {
- bool allow_active = args->result == MIG_TEST_FAIL;
- wait_for_migration_fail(from, allow_active);
} else {
- if (args->live) {
- /*
- * For initial iteration(s) we must do a full pass,
- * but for the final iteration, we need only wait
- * for some dirty mem before switching to converge
- */
- while (args->iterations > 1) {
- wait_for_migration_pass(from, &src_state);
- args->iterations--;
- }
- migrate_wait_for_dirty_mem(from, to);
+ wait_for_migration_complete(from);
+ /*
+ * Must wait for dst to finish reading all incoming
+ * data on the socket before issuing 'cont' otherwise
+ * it'll be ignored
+ */
+ wait_for_migration_complete(to);
- migrate_ensure_converge(from);
+ qtest_qmp_assert_success(to, "{ 'execute' : 'cont'}");
+ }
- /*
- * We do this first, as it has a timeout to stop us
- * hanging forever if migration didn't converge
- */
- wait_for_migration_complete(from);
+ wait_for_resume(to, &dst_state);
+
+ if (args->start.suspend_me) {
+ /* wakeup succeeds only if guest is suspended */
+ qtest_qmp_assert_success(to, "{'execute': 'system_wakeup'}");
+ }
- wait_for_stop(from, &src_state);
+ wait_for_serial(qtest_get_serial_path(to));
+}
- } else {
- wait_for_migration_complete(from);
- /*
- * Must wait for dst to finish reading all incoming
- * data on the socket before issuing 'cont' otherwise
- * it'll be ignored
- */
- wait_for_migration_complete(to);
+int test_precopy_common(MigrateCommon *args)
+{
+ QTestState *from, *to;
+ void *data_hook = NULL;
+ const char *listen_uri = args->uri ?: "tcp:127.0.0.1:0";
- qtest_qmp_assert_success(to, "{ 'execute' : 'cont'}");
- }
+ if (migrate_start(&from, &to, &args->start)) {
+ return -1;
+ }
+
+ if (args->start_hook) {
+ data_hook = args->start_hook(from, to);
+ }
- wait_for_resume(to, &dst_state);
+ if (args->result == MIG_TEST_SUCCEED) {
+ migrate_precopy_hop(from, to, listen_uri, args->uri, args);
+ } else {
+ QObject *channels = NULL;
+
+ migrate_incoming_qmp(to, listen_uri, NULL, "{}");
+
+ if (args->live) {
+ migrate_ensure_non_converge(from);
+ migrate_prepare_for_dirty_mem(from);
+ }
- if (args->start.suspend_me) {
- /* wakeup succeeds only if guest is suspended */
- qtest_qmp_assert_success(to, "{'execute': 'system_wakeup'}");
+ if (args->connect_channels) {
+ channels = qobject_from_json(args->connect_channels, &error_abort);
}
- wait_for_serial(qtest_get_serial_path(to));
+ if (args->result == MIG_TEST_QMP_ERROR) {
+ migrate_qmp_fail(from, args->uri, channels, "{}");
+ } else {
+ migrate_qmp(from, to, args->uri, channels, "{}");
+ wait_for_migration_fail(from, args->result == MIG_TEST_FAIL);
+ }
}
-finish:
if (args->end_hook) {
args->end_hook(from, to, data_hook);
}
@@ -1000,6 +1025,44 @@ void test_precopy_unix_common(MigrateCommon *args)
test_precopy_common(args);
}
+int test_precopy_chain(MigrateCommon *args)
+{
+ QTestState *from, *to, *to2;
+ const char *listen_uri = args->uri ?: "tcp:127.0.0.1:0";
+
+ /*
+ * Hook callbacks operate on a fixed (from, to) pair; they do not
+ * compose across multiple migration legs.
+ */
+ g_assert(!args->start_hook && !args->end_hook);
+
+ if (migrate_start(&from, &to, &args->start)) {
+ return -1;
+ }
+
+ /* First leg: A -> B */
+ migrate_precopy_hop(from, to, listen_uri, args->uri, args);
+
+ /*
+ * Second leg: B -> C.
+ */
+ qtest_quit(from);
+ migrate_setup_instance(to, &src_state, &args->start);
+
+ to2 = migrate_launch_dest("dest_serial2", &args->start);
+ if (!to2) {
+ qtest_quit(to);
+ return -1;
+ }
+ migrate_setup_instance(to2, &dst_state, &args->start);
+
+ migrate_precopy_hop(to, to2, listen_uri, NULL, args);
+
+ migrate_end(to, to2, true);
+
+ return 0;
+}
+
static void file_dirty_offset_region(void)
{
g_autofree char *path = g_strdup_printf("%s/%s", tmpfs, FILE_TEST_FILENAME);
diff --git a/tests/qtest/migration/framework.h b/tests/qtest/migration/framework.h
index f6936eb8c6..ca5289329a 100644
--- a/tests/qtest/migration/framework.h
+++ b/tests/qtest/migration/framework.h
@@ -254,6 +254,7 @@ void test_postcopy_common(MigrateCommon *args);
void test_postcopy_recovery_common(MigrateCommon *args,
PostcopyRecoveryFailStage fail_stage);
int test_precopy_common(MigrateCommon *args);
+int test_precopy_chain(MigrateCommon *args);
void test_precopy_unix_common(MigrateCommon *args);
void test_file_common(MigrateCommon *args, bool stop_src);
diff --git a/tests/qtest/migration/precopy-tests.c b/tests/qtest/migration/precopy-tests.c
index 194462c841..fccff76ef6 100644
--- a/tests/qtest/migration/precopy-tests.c
+++ b/tests/qtest/migration/precopy-tests.c
@@ -182,6 +182,11 @@ static void test_precopy_tcp_plain(char *name, MigrateCommon *args)
test_precopy_common(args);
}
+static void test_precopy_tcp_plain_chain(char *name, MigrateCommon *args)
+{
+ test_precopy_chain(args);
+}
+
static void test_precopy_tcp_switchover_ack(char *name, MigrateCommon *args)
{
/*
@@ -398,6 +403,20 @@ static void test_multifd_tcp_channels_none(char *name, MigrateCommon *args)
test_precopy_common(args);
}
+static void test_multifd_tcp_channels_chain(char *name, MigrateCommon *args)
+{
+ args->live = true;
+ args->connect_channels = ("[ { 'channel-type': 'main',"
+ " 'addr': { 'transport': 'socket',"
+ " 'type': 'inet',"
+ " 'host': '127.0.0.1',"
+ " 'port': '0' } } ]");
+
+ args->start.caps[MIGRATION_CAPABILITY_MULTIFD] = true;
+
+ test_precopy_chain(args);
+}
+
/*
* This test does:
* source target
@@ -1112,6 +1131,8 @@ void migration_test_add_precopy(MigrationTestEnv *env)
return;
}
+ migration_test_add("/migration/precopy/tcp/plain/chain",
+ test_precopy_tcp_plain_chain);
migration_test_add("/migration/precopy/tcp/plain/switchover-ack",
test_precopy_tcp_switchover_ack);
@@ -1133,6 +1154,8 @@ void migration_test_add_precopy(MigrationTestEnv *env)
}
migration_test_add("/migration/multifd/tcp/channels/plain/none",
test_multifd_tcp_channels_none);
+ migration_test_add("/migration/multifd/tcp/channels/plain/chain",
+ test_multifd_tcp_channels_chain);
migration_test_add("/migration/multifd/tcp/plain/zero-page/legacy",
test_multifd_tcp_zero_page_legacy);
migration_test_add("/migration/multifd/tcp/plain/zero-page/none",
--
2.50.1 (Apple Git-155)
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/3] tests/migration: Factor out per-process launch and setup helpers
2026-07-09 13:00 ` [PATCH 1/3] tests/migration: Factor out per-process launch and setup helpers phind.uet
@ 2026-08-20 15:13 ` Fabiano Rosas
0 siblings, 0 replies; 6+ messages in thread
From: Fabiano Rosas @ 2026-08-20 15:13 UTC (permalink / raw)
To: phind.uet, Peter Xu, Laurent Vivier, Paolo Bonzini
Cc: Nguyen Dinh Phi, qemu-devel
phind.uet@gmail.com writes:
> From: Nguyen Dinh Phi <phind.uet@gmail.com>
>
Hi, sorry for the delay, this series conflicts with some ongoing work
I'm doing so I had to find time to double check.
> migrate_start() always spawned source and destination together, and
> migrate_start_set_capabilities() required both QTestState pointers at
> once. This coupling prevents launching a third QEMU instance or
> re-configuring an existing destination as a new source.
>
What about migrate_end? Don't you need to allow instances to be freed
individually as well?
> Split the logic into three public helpers:
>
> migrate_launch_source() / migrate_launch_dest()
> Spawn a single QEMU process and record its serial file path on
> the returned QTestState.
>
> migrate_setup_instance()
> Register the event callback and apply migration capabilities to
> one already-running process. Can be called again to re-wire the
> same process for a different role.
>
> migrate_start() is kept for backward compatibility and now delegates
> to these helpers internally.
>
> Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com>
> ---
> tests/qtest/migration/framework.c | 253 +++++++++++++++++-------------
> tests/qtest/migration/framework.h | 18 ++-
> 2 files changed, 165 insertions(+), 106 deletions(-)
>
> diff --git a/tests/qtest/migration/framework.c b/tests/qtest/migration/framework.c
> index a830b96f41..305b8968ff 100644
> --- a/tests/qtest/migration/framework.c
> +++ b/tests/qtest/migration/framework.c
> @@ -208,9 +208,11 @@ static QList *migrate_start_get_qmp_capabilities(const MigrateStart *args)
> return capabilities;
> }
>
> -static void migrate_start_set_capabilities(QTestState *from, QTestState *to,
> - MigrateStart *args)
> +void migrate_setup_instance(QTestState *who, QTestMigrationState *state,
> + MigrateStart *args)
> {
> + qtest_qmp_set_event_callback(who, migrate_watch_for_events, state);
You could pass in a defer_connect boolean in here and exit at this
point, no need to set the callback operation in the caller as well.
> + *state = (QTestMigrationState) { .suspend_me = args->suspend_me };
> /*
> * MigrationCapability_lookup and MIGRATION_CAPABILITY_ constants
> * are from qapi-types-migration.h.
> @@ -220,25 +222,13 @@ static void migrate_start_set_capabilities(QTestState *from, QTestState *to,
> * Enable return path first, since other features depend on it.
> */
> if (args->caps[MIGRATION_CAPABILITY_RETURN_PATH]) {
> - if (from) {
> - migrate_set_capability(from, "return-path", true);
> - }
> - if (to) {
> - migrate_set_capability(to, "return-path", true);
> - }
> + migrate_set_capability(who, "return-path", true);
> }
>
> for (uint8_t i = 0; i < MIGRATION_CAPABILITY__MAX; i++) {
> - if (!args->caps[i]) {
> - continue;
> - }
> - if (from) {
> - migrate_set_capability(from,
> - MigrationCapability_lookup.array[i], true);
> - }
> - if (to) {
> - migrate_set_capability(to,
> - MigrationCapability_lookup.array[i], true);
> + if (args->caps[i]) {
> + migrate_set_capability(who, MigrationCapability_lookup.array[i],
> + true);
> }
> }
>
> @@ -246,26 +236,17 @@ static void migrate_start_set_capabilities(QTestState *from, QTestState *to,
> * Always enable migration events. Libvirt always uses it, let's try
> * to mimic as closer as that.
> */
> - migrate_set_capability(from, "events", true);
> - if (!args->defer_target_connect && to) {
> - migrate_set_capability(to, "events", true);
> - }
> + migrate_set_capability(who, "events", true);
>
> - /*
> + /*
Please keep the open comment mark in the correct place.
> * Default number of channels should be fine for most
> * tests. Individual tests can override by calling
> * migrate_set_parameter() directly.
> */
> if (args->caps[MIGRATION_CAPABILITY_MULTIFD]) {
> - migrate_set_parameter_int(from, "multifd-channels",
> + migrate_set_parameter_int(who, "multifd-channels",
> MULTIFD_TEST_CHANNELS);
> - if (to) {
> - migrate_set_parameter_int(to, "multifd-channels",
> - MULTIFD_TEST_CHANNELS);
> - }
> }
> -
> - return;
> }
>
> static char *test_shmem_path(void)
> @@ -308,12 +289,28 @@ static char *migrate_mem_type_get_opts(MemType type, const char *memory_size)
> return opts;
> }
>
> -int migrate_args(char **from, char **to, MigrateStart *args)
> +/*
> + * Build a QEMU command line for one migration participant.
> + *
> + * @serial_name : serial output file basename under tmpfs
> + * @is_target : set to true if the new qemu process is destination side
If we now have launch_source|dest, we shouldn't need to pass this flag in.
> + * @extra_opts : extra arguments
> + * @defer_events : when true and is_target is set, use the command-line
> + * event flag instead of the QMP capability (for deferred
> + * monitor connections)
Same here.
> + * @args : common process settings
> + *
> + * Returns 0 and sets *cmd_out on success. Returns -1 and calls
> + * g_test_skip() if the machine type is not available.
> + */
> +static int migrate_build_cmd(const char *serial_name,
> + bool is_target,
> + const char *extra_opts,
> + bool defer_events,
> + MigrateStart *args,
> + char **cmd_out)
> {
> - /* options for source and target */
> g_autofree gchar *arch_opts = NULL;
> - gchar *cmd_source = NULL;
> - gchar *cmd_target = NULL;
> const gchar *ignore_stderr;
> g_autofree char *mem_object = NULL;
> const char *kvm_opts = NULL;
> @@ -323,16 +320,10 @@ int migrate_args(char **from, char **to, MigrateStart *args)
> g_autofree char *machine = NULL;
> const char *bootpath = bootfile_get();
> g_autofree char *memory_backend = NULL;
> - const char *events;
>
> if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
> memory_size = "150M";
> -
> - if (g_str_equal(arch, "i386")) {
> - machine_alias = "pc";
> - } else {
> - machine_alias = "q35";
> - }
> + machine_alias = g_str_equal(arch, "i386") ? "pc" : "q35";
We usually wouldn't include changes of this kind among other
things. This could be an individual patch if you think it's worth it.
(I think we should just leave it alone)
> arch_opts = g_strdup_printf(
> "-drive if=none,id=d0,file=%s,format=raw "
> "-device ide-hd,drive=d0,secs=1,cyls=1,heads=1", bootpath);
> @@ -346,13 +337,13 @@ int migrate_args(char **from, char **to, MigrateStart *args)
> end_address = S390_TEST_MEM_END;
> } else if (strcmp(arch, "ppc64") == 0) {
> memory_size = "256M";
> - start_address = PPC_TEST_MEM_START;
> - end_address = PPC_TEST_MEM_END;
> machine_alias = "pseries";
> machine_opts = "vsmt=8";
> arch_opts = g_strdup_printf(
> "-nodefaults -machine " PSERIES_DEFAULT_CAPABILITIES " "
> "-bios %s", bootpath);
> + start_address = PPC_TEST_MEM_START;
> + end_address = PPC_TEST_MEM_END;
This moved for no reason...
> } else if (strcmp(arch, "aarch64") == 0) {
> memory_size = "150M";
> machine_alias = "virt";
> @@ -394,53 +385,103 @@ int migrate_args(char **from, char **to, MigrateStart *args)
> }
>
> if (!qtest_has_machine(machine_alias)) {
> - g_autofree char *msg = g_strdup_printf("machine %s not supported", machine_alias);
> + g_autofree char *msg = g_strdup_printf("machine %s not supported",
> + machine_alias);
Same here, this can stay as it is.
> g_test_skip(msg);
> return -1;
> }
>
> machine = resolve_machine_version(machine_alias, QEMU_ENV_SRC,
> QEMU_ENV_DST);
> -
> g_test_message("Using machine type: %s", machine);
>
> - cmd_source = g_strdup_printf("-accel kvm%s -accel tcg "
> - "-machine %s,%s "
> - "-name source,debug-threads=on "
> - "%s "
> - "-serial file:%s/src_serial "
> - "%s %s %s",
> - kvm_opts ? kvm_opts : "",
> - machine, machine_opts,
> - memory_backend, tmpfs,
> - arch_opts ? arch_opts : "",
> - args->opts_source ? args->opts_source : "",
> - ignore_stderr);
> + if (is_target) {
> + /*
> + * If the monitor connection is deferred, enable events on the command
> + * line so none are missed. This is for testing only, do not set
> + * migration options like this in general.
> + */
> + const char *events = defer_events ? "-global migration.x-events=on"
> + : "";
> + *cmd_out = g_strdup_printf(
> + "-accel kvm%s -accel tcg "
> + "-machine %s,%s "
> + "-name target,debug-threads=on "
> + "%s "
> + "-serial file:%s/%s "
> + "-incoming defer "
> + "%s %s %s %s",
> + kvm_opts ? kvm_opts : "",
> + machine, machine_opts,
> + memory_backend, tmpfs, serial_name,
> + events,
> + arch_opts ? arch_opts : "",
> + extra_opts ? extra_opts : "",
> + ignore_stderr);
> + } else {
> + *cmd_out = g_strdup_printf(
> + "-accel kvm%s -accel tcg "
> + "-machine %s,%s "
> + "-name source,debug-threads=on "
> + "%s "
> + "-serial file:%s/%s "
> + "%s %s %s",
> + kvm_opts ? kvm_opts : "",
> + machine, machine_opts,
> + memory_backend, tmpfs, serial_name,
> + arch_opts ? arch_opts : "",
> + extra_opts ? extra_opts : "",
> + ignore_stderr);
> + }
Let's move all the instance-specific information into the upper levels,
this conditional can go away, all information comes in via extra_opts:
*cmd_out = g_strdup_printf(
"-accel kvm%s -accel tcg "
"-machine %s,%s "
"%s "
"-serial file:%s/%s "
"%s %s %s",
kvm_opts ? kvm_opts : "",
machine, machine_opts,
memory_backend, tmpfs, serial_name,
arch_opts ? arch_opts : "",
extra_opts ? extra_opts : "",
ignore_stderr);
>
> - /*
> - * If the monitor connection is deferred, enable events on the command line
> - * so none are missed. This is for testing only, do not set migration
> - * options like this in general.
> - */
> - events = args->defer_target_connect ? "-global migration.x-events=on" : "";
> -
> - cmd_target = g_strdup_printf("-accel kvm%s -accel tcg "
> - "-machine %s,%s "
> - "-name target,debug-threads=on "
> - "%s "
> - "-serial file:%s/dest_serial "
> - "-incoming defer "
> - "%s %s %s %s",
> - kvm_opts ? kvm_opts : "",
> - machine, machine_opts,
> - memory_backend, tmpfs,
> - events,
> - arch_opts ? arch_opts : "",
> - args->opts_target ? args->opts_target : "",
> - ignore_stderr);
> -
> - *from = cmd_source;
> - *to = cmd_target;
> + return 0;
> +}
> +
> +/*
> + * Launch a QEMU process as a migration source.
> + * Returns the QTestState on success, or NULL otherwise
> + */
> +QTestState *migrate_launch_source(const char *serial_name, MigrateStart *args)
If this is "launch_source" we already know the serial name is
"src_serial", no need to pass in.
The launch_* functions could return bool and receive the **qts as first
argument.
> +{
> + g_autofree char *cmd = NULL;
> + g_autoptr(QList) capabilities = migrate_start_get_qmp_capabilities(args);
> +
> + if (migrate_build_cmd(serial_name, false, args->opts_source,
> + false, args, &cmd)) {
Here's what I'm thinking to remove the instance-specific information
from migrate_build_cmd:
static bool migrate_launch_instance(QTestState **qts, MigrateStart *args,
QTestMigrationState *state, const char *env,
bool defer_connect, char *cmd)
{
g_autoptr(QList) capabilities = migrate_start_get_qmp_capabilities(args);
*qts = qtest_init_ext(env, cmd, capabilities, !defer_connect);
if (*qts) {
migrate_setup_instance(*qts, state, args, defer_connect);
}
return !!*qts;
}
static bool migrate_build_dest(MigrateStart *args, char **cmd)
{
g_autofree char *opts = NULL;
int r;
if (args->only_source) {
return true;
}
/*
* If the monitor connection is deferred, enable events on the command
* line so none are missed. This is for testing only, do not set
* migration options like this in general.
*/
opts = g_strdup_printf(
"-name target,debug-threads=on "
"-incoming defer "
"%s %s",
args->defer_target_connect ? "-global migration.x-events=on" : "",
args->opts_target ?: "");
r = migrate_build_cmd("dest_serial", opts, args, cmd);
return r == 0;
}
static bool migrate_launch_dest(QTestState **qts, MigrateStart *args)
{
g_autofree char *cmd = NULL;
if (!migrate_build_dest(args, &cmd)){
return false;
}
if (cmd && !migrate_launch_instance(qts, args, &dst_state, QEMU_ENV_DST,
args->defer_target_connect, cmd)) {
return false;
}
return true;
}
migrate_args -> migrate_build_dest
migrate_start -> migrate_launch_dest -> migrate_build_dest
And similarly for the source.
What do you think?
> + return NULL;
> + }
> + return qtest_init_ext(QEMU_ENV_SRC, cmd, capabilities, true);
> +}
> +
> +/*
> + * Launch a QEMU process as a migration destination.
> + * Returns the QTestState on success, or NULL otherwise
> + */
> +QTestState *migrate_launch_dest(const char *serial_name, MigrateStart *args)
> +{
> + g_autofree char *cmd = NULL;
> + g_autoptr(QList) capabilities = migrate_start_get_qmp_capabilities(args);
> +
> + if (migrate_build_cmd(serial_name, true, args->opts_target,
> + args->defer_target_connect, args, &cmd)) {
> + return NULL;
> + }
> + return qtest_init_ext(QEMU_ENV_DST, cmd, capabilities,
> + !args->defer_target_connect);
> +}
> +
> +int migrate_args(char **from, char **to, MigrateStart *args)
> +{
> + if (migrate_build_cmd("src_serial", false, args->opts_source,
> + false, args, from)) {
> + return -1;
> + }
> + if (migrate_build_cmd("dest_serial", true, args->opts_target,
> + args->defer_target_connect, args, to)) {
> + g_free(*from);
> + *from = NULL;
> + return -1;
> + }
> return 0;
> }
>
> @@ -482,43 +523,45 @@ static void migrate_mem_type_cleanup(MemType type)
>
> int migrate_start(QTestState **from, QTestState **to, MigrateStart *args)
> {
> - g_autofree gchar *cmd_source = NULL;
> - g_autofree gchar *cmd_target = NULL;
> - g_autoptr(QList) capabilities = migrate_start_get_qmp_capabilities(args);
> -
> if (!migrate_mem_type_prepare(args->mem_type)) {
> return -1;
> }
>
> - dst_state = (QTestMigrationState) { };
> - src_state = (QTestMigrationState) { };
> + src_state = (QTestMigrationState){};
> + dst_state = (QTestMigrationState){};
> bootfile_create(qtest_get_arch(), tmpfs, args->suspend_me);
> - src_state.suspend_me = args->suspend_me;
> -
> - if (migrate_args(&cmd_source, &cmd_target, args)) {
> - return -1;
> - }
>
> if (!args->only_target) {
The only_* checks can go into the _launch_source level, keeps this
function cleaner.
> - *from = qtest_init_ext(QEMU_ENV_SRC, cmd_source, capabilities, true);
> - qtest_qmp_set_event_callback(*from,
> - migrate_watch_for_events,
> - &src_state);
> + *from = migrate_launch_source("src_serial", args);
> + if (!*from) {
> + return -1;
> + }
> + migrate_setup_instance(*from, &src_state, args);
> }
>
> if (!args->only_source) {
> - *to = qtest_init_ext(QEMU_ENV_DST, cmd_target, capabilities,
> - !args->defer_target_connect);
> - qtest_qmp_set_event_callback(*to,
> - migrate_watch_for_events,
> - &dst_state);
> + *to = migrate_launch_dest("dest_serial", args);
> + if (!*to) {
> + if (!args->only_target) {
> + qtest_quit(*from);
> + }
> + return -1;
> + }
> + if (!args->defer_target_connect) {
This check would move into migrate_setup_instance.
> + migrate_setup_instance(*to, &dst_state, args);
> + } else {
> + /*
> + * The monitor is not connected yet; only register the event
> + * callback so no events are missed.
> + * The caller must call migrate_setup_instance() after
> + * qtest_connect() if it wants to setup any capability
> + */
> + qtest_qmp_set_event_callback(*to, migrate_watch_for_events,
> + &dst_state);
> + }
> }
>
> migrate_mem_type_cleanup(args->mem_type);
> - migrate_start_set_capabilities(*from,
> - args->only_source ? NULL : *to,
> - args);
> -
> return 0;
> }
>
> diff --git a/tests/qtest/migration/framework.h b/tests/qtest/migration/framework.h
> index 941cbd7102..f054ef8f4d 100644
> --- a/tests/qtest/migration/framework.h
> +++ b/tests/qtest/migration/framework.h
> @@ -225,10 +225,27 @@ typedef struct {
> bool live;
> } MigrateCommon;
>
> +typedef struct QTestMigrationState QTestMigrationState;
> +
> void wait_for_serial(const char *side);
> void migrate_prepare_for_dirty_mem(QTestState *from);
> void migrate_wait_for_dirty_mem(QTestState *from, QTestState *to);
>
> +/*
> + * Start a QEMU process which has serial set to @serial_name
> + */
> +QTestState *migrate_launch_source(const char *serial_name, MigrateStart *args);
> +/*
> + * Start a QEMU process which has serial set to @serial_name
> + */
> +QTestState *migrate_launch_dest(const char *serial_name, MigrateStart *args);
> +/*
> + * Registers the event callback and sets migration capabilities on an
> + * already-running process
> + */
> +void migrate_setup_instance(QTestState *who, QTestMigrationState *state,
> + MigrateStart *args);
These don't need to be exported, keep them static.
> +
> int migrate_args(char **from, char **to, MigrateStart *args);
> int migrate_start(QTestState **from, QTestState **to, MigrateStart *args);
> void migrate_end(QTestState *from, QTestState *to, bool test_dest);
> @@ -240,7 +257,6 @@ int test_precopy_common(MigrateCommon *args);
> void test_precopy_unix_common(MigrateCommon *args);
> void test_file_common(MigrateCommon *args, bool stop_src);
>
> -typedef struct QTestMigrationState QTestMigrationState;
> QTestMigrationState *get_src(void);
> QTestMigrationState *get_dst(void);
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 0/3] Support chain migration in test
2026-07-09 13:00 [PATCH 0/3] Support chain migration in test phind.uet
` (2 preceding siblings ...)
2026-07-09 13:00 ` [PATCH 3/3] tests/migration: Add chain (A to B to C) precopy migration tests phind.uet
@ 2026-08-20 15:22 ` Fabiano Rosas
3 siblings, 0 replies; 6+ messages in thread
From: Fabiano Rosas @ 2026-08-20 15:22 UTC (permalink / raw)
To: phind.uet, Laurent Vivier, Paolo Bonzini, Lukas Straub, Peter Xu,
Maciej S. Szmigiero, Mark Kanda, Ben Chaney
Cc: Nguyen Dinh Phi, qemu-devel
phind.uet@gmail.com writes:
> From: Nguyen Dinh Phi <phind.uet@gmail.com>
>
> This series adds test infrastructure and test cases for multi-hop chain
> migration, where a VM migrates from host A to B and then from B to C.
>
> The migration test TODO list mentions ping-pong migration (A→B→A) as a
> desirable scenario; the true ping-pong (A→B→A) would require the original
> source A to become a destination for the return leg.
> This is not possible: a QEMU process launched without -incoming cannot
> later accept an incoming migration stream. Instead, this series implements
> chain migration (A→B→C): B was already launched with -incoming and can
> be re-wired as the source for the next hop, while a fresh QEMU instance C
> is started as the new destination.
>
> Nguyen Dinh Phi (3):
> tests/migration: Factor out per-process launch and setup helpers
> tests/migration: Retrieve serial path from QTestState
> tests/migration: Add chain (A to B to C) precopy migration tests
>
> tests/qtest/libqtest.c | 16 +
> tests/qtest/libqtest.h | 8 +
> tests/qtest/migration/colo-tests.c | 14 +-
> tests/qtest/migration/cpr-tests.c | 8 +-
> tests/qtest/migration/framework.c | 475 ++++++++++++++++----------
> tests/qtest/migration/framework.h | 21 +-
> tests/qtest/migration/misc-tests.c | 4 +-
> tests/qtest/migration/precopy-tests.c | 51 ++-
> 8 files changed, 389 insertions(+), 208 deletions(-)
This has been attempted before, but we ended up not continuing the work
for other reasons. I think your ideas on the first patch are a step in
the right direction. As for the serial work, I'm not so sure we should
be adding migration-specific data into QTestState, even though the
serial is not technically exclusive to migration. I need to give it a
bit more thought.
Here are the links to the previous work (for reference, I don't have
plans to carry it forward at the moment):
Cleanups and dealing with serial:
https://lore.kernel.org/all/20241125144612.16194-2-farosas@suse.de/
https://lore.kernel.org/all/20241125144612.16194-3-farosas@suse.de/
https://lore.kernel.org/all/20241125144612.16194-4-farosas@suse.de/
Ping-pong test:
https://lore.kernel.org/all/20241125144612.16194-6-farosas@suse.de/
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-08-20 15:23 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-07-09 13:00 [PATCH 0/3] Support chain migration in test phind.uet
2026-07-09 13:00 ` [PATCH 1/3] tests/migration: Factor out per-process launch and setup helpers phind.uet
2026-08-20 15:13 ` Fabiano Rosas
2026-07-09 13:00 ` [PATCH 2/3] tests/migration: Retrieve serial path from QTestState phind.uet
2026-07-09 13:00 ` [PATCH 3/3] tests/migration: Add chain (A to B to C) precopy migration tests phind.uet
2026-08-20 15:22 ` [PATCH 0/3] Support chain migration in test Fabiano Rosas
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