* [Qemu-devel] [PULL 01/14] migration: Use proper types in json
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 02/14] migration: print features as on off Juan Quintela
` (14 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx
We use int for everything (int64_t), and then we check that value is
between 0 and 255. Change it to the valid types.
This change only happens for HMP. QMP always use bytes and similar.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
hmp.c | 22 +++++++++++-----------
migration/migration.c | 49 ++++++++++++++++++++-----------------------------
qapi/migration.json | 20 ++++++++++----------
3 files changed, 41 insertions(+), 50 deletions(-)
diff --git a/hmp.c b/hmp.c
index 35a7041824..1727c9c003 100644
--- a/hmp.c
+++ b/hmp.c
@@ -293,23 +293,23 @@ void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict)
if (params) {
assert(params->has_compress_level);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_COMPRESS_LEVEL),
params->compress_level);
assert(params->has_compress_threads);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_COMPRESS_THREADS),
params->compress_threads);
assert(params->has_decompress_threads);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_DECOMPRESS_THREADS),
params->decompress_threads);
assert(params->has_cpu_throttle_initial);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_CPU_THROTTLE_INITIAL),
params->cpu_throttle_initial);
assert(params->has_cpu_throttle_increment);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_CPU_THROTTLE_INCREMENT),
params->cpu_throttle_increment);
assert(params->has_tls_creds);
@@ -321,28 +321,28 @@ void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict)
MigrationParameter_str(MIGRATION_PARAMETER_TLS_HOSTNAME),
params->tls_hostname);
assert(params->has_max_bandwidth);
- monitor_printf(mon, "%s: %" PRId64 " bytes/second\n",
+ monitor_printf(mon, "%s: %" PRIu64 " bytes/second\n",
MigrationParameter_str(MIGRATION_PARAMETER_MAX_BANDWIDTH),
params->max_bandwidth);
assert(params->has_downtime_limit);
- monitor_printf(mon, "%s: %" PRId64 " milliseconds\n",
+ monitor_printf(mon, "%s: %" PRIu64 " milliseconds\n",
MigrationParameter_str(MIGRATION_PARAMETER_DOWNTIME_LIMIT),
params->downtime_limit);
assert(params->has_x_checkpoint_delay);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_X_CHECKPOINT_DELAY),
params->x_checkpoint_delay);
assert(params->has_block_incremental);
monitor_printf(mon, "%s: %s\n",
MigrationParameter_str(MIGRATION_PARAMETER_BLOCK_INCREMENTAL),
params->block_incremental ? "on" : "off");
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_X_MULTIFD_CHANNELS),
params->x_multifd_channels);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %u\n",
MigrationParameter_str(MIGRATION_PARAMETER_X_MULTIFD_PAGE_COUNT),
params->x_multifd_page_count);
- monitor_printf(mon, "%s: %" PRId64 "\n",
+ monitor_printf(mon, "%s: %" PRIu64 "\n",
MigrationParameter_str(MIGRATION_PARAMETER_XBZRLE_CACHE_SIZE),
params->xbzrle_cache_size);
}
diff --git a/migration/migration.c b/migration/migration.c
index 4de3b551fe..8d2372394c 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -741,22 +741,20 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
static bool migrate_params_check(MigrationParameters *params, Error **errp)
{
if (params->has_compress_level &&
- (params->compress_level < 0 || params->compress_level > 9)) {
+ (params->compress_level > 9)) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "compress_level",
"is invalid, it should be in the range of 0 to 9");
return false;
}
- if (params->has_compress_threads &&
- (params->compress_threads < 1 || params->compress_threads > 255)) {
+ if (params->has_compress_threads && (params->compress_threads < 1)) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
"compress_threads",
"is invalid, it should be in the range of 1 to 255");
return false;
}
- if (params->has_decompress_threads &&
- (params->decompress_threads < 1 || params->decompress_threads > 255)) {
+ if (params->has_decompress_threads && (params->decompress_threads < 1)) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
"decompress_threads",
"is invalid, it should be in the range of 1 to 255");
@@ -781,38 +779,31 @@ static bool migrate_params_check(MigrationParameters *params, Error **errp)
return false;
}
- if (params->has_max_bandwidth &&
- (params->max_bandwidth < 0 || params->max_bandwidth > SIZE_MAX)) {
+ if (params->has_max_bandwidth && (params->max_bandwidth > SIZE_MAX)) {
error_setg(errp, "Parameter 'max_bandwidth' expects an integer in the"
" range of 0 to %zu bytes/second", SIZE_MAX);
return false;
}
if (params->has_downtime_limit &&
- (params->downtime_limit < 0 ||
- params->downtime_limit > MAX_MIGRATE_DOWNTIME)) {
+ (params->downtime_limit > MAX_MIGRATE_DOWNTIME)) {
error_setg(errp, "Parameter 'downtime_limit' expects an integer in "
"the range of 0 to %d milliseconds",
MAX_MIGRATE_DOWNTIME);
return false;
}
- if (params->has_x_checkpoint_delay && (params->x_checkpoint_delay < 0)) {
- error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
- "x_checkpoint_delay",
- "is invalid, it should be positive");
- return false;
- }
- if (params->has_x_multifd_channels &&
- (params->x_multifd_channels < 1 || params->x_multifd_channels > 255)) {
+ /* x_checkpoint_delay is now always positive */
+
+ if (params->has_x_multifd_channels && (params->x_multifd_channels < 1)) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
"multifd_channels",
"is invalid, it should be in the range of 1 to 255");
return false;
}
if (params->has_x_multifd_page_count &&
- (params->x_multifd_page_count < 1 ||
- params->x_multifd_page_count > 10000)) {
+ (params->x_multifd_page_count < 1 ||
+ params->x_multifd_page_count > 10000)) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
"multifd_page_count",
"is invalid, it should be in the range of 1 to 10000");
@@ -2394,33 +2385,33 @@ static Property migration_properties[] = {
send_section_footer, true),
/* Migration parameters */
- DEFINE_PROP_INT64("x-compress-level", MigrationState,
+ DEFINE_PROP_UINT8("x-compress-level", MigrationState,
parameters.compress_level,
DEFAULT_MIGRATE_COMPRESS_LEVEL),
- DEFINE_PROP_INT64("x-compress-threads", MigrationState,
+ DEFINE_PROP_UINT8("x-compress-threads", MigrationState,
parameters.compress_threads,
DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT),
- DEFINE_PROP_INT64("x-decompress-threads", MigrationState,
+ DEFINE_PROP_UINT8("x-decompress-threads", MigrationState,
parameters.decompress_threads,
DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT),
- DEFINE_PROP_INT64("x-cpu-throttle-initial", MigrationState,
+ DEFINE_PROP_UINT8("x-cpu-throttle-initial", MigrationState,
parameters.cpu_throttle_initial,
DEFAULT_MIGRATE_CPU_THROTTLE_INITIAL),
- DEFINE_PROP_INT64("x-cpu-throttle-increment", MigrationState,
+ DEFINE_PROP_UINT8("x-cpu-throttle-increment", MigrationState,
parameters.cpu_throttle_increment,
DEFAULT_MIGRATE_CPU_THROTTLE_INCREMENT),
- DEFINE_PROP_INT64("x-max-bandwidth", MigrationState,
+ DEFINE_PROP_SIZE("x-max-bandwidth", MigrationState,
parameters.max_bandwidth, MAX_THROTTLE),
- DEFINE_PROP_INT64("x-downtime-limit", MigrationState,
+ DEFINE_PROP_UINT64("x-downtime-limit", MigrationState,
parameters.downtime_limit,
DEFAULT_MIGRATE_SET_DOWNTIME),
- DEFINE_PROP_INT64("x-checkpoint-delay", MigrationState,
+ DEFINE_PROP_UINT32("x-checkpoint-delay", MigrationState,
parameters.x_checkpoint_delay,
DEFAULT_MIGRATE_X_CHECKPOINT_DELAY),
- DEFINE_PROP_INT64("x-multifd-channels", MigrationState,
+ DEFINE_PROP_UINT8("x-multifd-channels", MigrationState,
parameters.x_multifd_channels,
DEFAULT_MIGRATE_MULTIFD_CHANNELS),
- DEFINE_PROP_INT64("x-multifd-page-count", MigrationState,
+ DEFINE_PROP_UINT32("x-multifd-page-count", MigrationState,
parameters.x_multifd_page_count,
DEFAULT_MIGRATE_MULTIFD_PAGE_COUNT),
DEFINE_PROP_SIZE("xbzrle-cache-size", MigrationState,
diff --git a/qapi/migration.json b/qapi/migration.json
index 03f57c9616..4cd3d13158 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -668,19 +668,19 @@
# Since: 2.4
##
{ 'struct': 'MigrationParameters',
- 'data': { '*compress-level': 'int',
- '*compress-threads': 'int',
- '*decompress-threads': 'int',
- '*cpu-throttle-initial': 'int',
- '*cpu-throttle-increment': 'int',
+ 'data': { '*compress-level': 'uint8',
+ '*compress-threads': 'uint8',
+ '*decompress-threads': 'uint8',
+ '*cpu-throttle-initial': 'uint8',
+ '*cpu-throttle-increment': 'uint8',
'*tls-creds': 'str',
'*tls-hostname': 'str',
- '*max-bandwidth': 'int',
- '*downtime-limit': 'int',
- '*x-checkpoint-delay': 'int',
+ '*max-bandwidth': 'size',
+ '*downtime-limit': 'uint64',
+ '*x-checkpoint-delay': 'uint32',
'*block-incremental': 'bool' ,
- '*x-multifd-channels': 'int',
- '*x-multifd-page-count': 'int',
+ '*x-multifd-channels': 'uint8',
+ '*x-multifd-page-count': 'uint32',
'*xbzrle-cache-size': 'size' } }
##
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 02/14] migration: print features as on off
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 01/14] migration: Use proper types in json Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 03/14] migration: free addr in the same function that we created it Juan Quintela
` (13 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx
Once there, do one thing for line
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
migration/migration.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/migration/migration.c b/migration/migration.c
index 8d2372394c..19917a4b5b 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2366,10 +2366,15 @@ void migration_global_dump(Monitor *mon)
{
MigrationState *ms = migrate_get_current();
- monitor_printf(mon, "globals: store-global-state=%d, only_migratable=%d, "
- "send-configuration=%d, send-section-footer=%d\n",
- ms->store_global_state, ms->only_migratable,
- ms->send_configuration, ms->send_section_footer);
+ monitor_printf(mon, "globals:\n");
+ monitor_printf(mon, "store-global-state: %s\n",
+ ms->store_global_state ? "on" : "off");
+ monitor_printf(mon, "only-migratable: %s\n",
+ ms->only_migratable ? "on" : "off");
+ monitor_printf(mon, "send-configuration: %s\n",
+ ms->send_configuration ? "on" : "off");
+ monitor_printf(mon, "send-section-footer: %s\n",
+ ms->send_section_footer ? "on" : "off");
}
#define DEFINE_PROP_MIG_CAP(name, x) \
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 03/14] migration: free addr in the same function that we created it
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 01/14] migration: Use proper types in json Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 02/14] migration: print features as on off Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 04/14] docs: Convert migration.txt to rst Juan Quintela
` (12 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx
Otherwise, we can't use it after calling socket_start_incoming_migration
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
migration/socket.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/migration/socket.c b/migration/socket.c
index dee869044a..3a8232dd2d 100644
--- a/migration/socket.c
+++ b/migration/socket.c
@@ -172,7 +172,6 @@ static void socket_start_incoming_migration(SocketAddress *saddr,
if (qio_channel_socket_listen_sync(listen_ioc, saddr, errp) < 0) {
object_unref(OBJECT(listen_ioc));
- qapi_free_SocketAddress(saddr);
return;
}
@@ -181,7 +180,6 @@ static void socket_start_incoming_migration(SocketAddress *saddr,
socket_accept_incoming_migration,
listen_ioc,
(GDestroyNotify)object_unref);
- qapi_free_SocketAddress(saddr);
}
void tcp_start_incoming_migration(const char *host_port, Error **errp)
@@ -191,6 +189,7 @@ void tcp_start_incoming_migration(const char *host_port, Error **errp)
if (!err) {
socket_start_incoming_migration(saddr, &err);
}
+ qapi_free_SocketAddress(saddr);
error_propagate(errp, err);
}
@@ -198,4 +197,5 @@ void unix_start_incoming_migration(const char *path, Error **errp)
{
SocketAddress *saddr = unix_build_address(path);
socket_start_incoming_migration(saddr, errp);
+ qapi_free_SocketAddress(saddr);
}
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 04/14] docs: Convert migration.txt to rst
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (2 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 03/14] migration: free addr in the same function that we created it Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 05/14] migration: free result string Juan Quintela
` (11 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Mostly just manual conversion with very minor fixes.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Kashyap Chamarthy <kchamart@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
docs/devel/{migration.txt => migration.rst} | 470 +++++++++++++++-------------
1 file changed, 247 insertions(+), 223 deletions(-)
rename docs/devel/{migration.txt => migration.rst} (58%)
diff --git a/docs/devel/migration.txt b/docs/devel/migration.rst
similarity index 58%
rename from docs/devel/migration.txt
rename to docs/devel/migration.rst
index 4030703726..bf97080dac 100644
--- a/docs/devel/migration.txt
+++ b/docs/devel/migration.rst
@@ -1,4 +1,6 @@
-= Migration =
+=========
+Migration
+=========
QEMU has code to load/save the state of the guest that it is running.
These are two complementary operations. Saving the state just does
@@ -26,7 +28,8 @@ the guest to be stopped. Typically the time that the guest is
unresponsive during live migration is the low hundred of milliseconds
(notice that this depends on a lot of things).
-=== Types of migration ===
+Types of migration
+==================
Now that we have talked about live migration, there are several ways
to do migration:
@@ -41,49 +44,21 @@ All these four migration protocols use the same infrastructure to
save/restore state devices. This infrastructure is shared with the
savevm/loadvm functionality.
-=== State Live Migration ===
+State Live Migration
+====================
This is used for RAM and block devices. It is not yet ported to vmstate.
<Fill more information here>
-=== What is the common infrastructure ===
+Common infrastructure
+=====================
-QEMU uses a QEMUFile abstraction to be able to do migration. Any type
-of migration that wants to use QEMU infrastructure has to create a
-QEMUFile with:
+The files, sockets or fd's that carry the migration stream are abstracted by
+the ``QEMUFile`` type (see `migration/qemu-file.h`). In most cases this
+is connected to a subtype of ``QIOChannel`` (see `io/`).
-QEMUFile *qemu_fopen_ops(void *opaque,
- QEMUFilePutBufferFunc *put_buffer,
- QEMUFileGetBufferFunc *get_buffer,
- QEMUFileCloseFunc *close);
-
-The functions have the following functionality:
-
-This function writes a chunk of data to a file at the given position.
-The pos argument can be ignored if the file is only used for
-streaming. The handler should try to write all of the data it can.
-
-typedef int (QEMUFilePutBufferFunc)(void *opaque, const uint8_t *buf,
- int64_t pos, int size);
-
-Read a chunk of data from a file at the given position. The pos argument
-can be ignored if the file is only be used for streaming. The number of
-bytes actually read should be returned.
-
-typedef int (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
- int64_t pos, int size);
-
-Close a file and return an error code.
-
-typedef int (QEMUFileCloseFunc)(void *opaque);
-
-You can use any internal state that you need using the opaque void *
-pointer that is passed to all functions.
-
-The important functions for us are put_buffer()/get_buffer() that
-allow to write/read a buffer into the QEMUFile.
-
-=== How to save the state of one device ===
+Saving the state of one device
+==============================
The state of a device is saved using intermediate buffers. There are
some helper functions to assist this saving.
@@ -93,34 +68,38 @@ version. When we migrate a device, we save/load the state as a series
of fields. Some times, due to bugs or new functionality, we need to
change the state to store more/different information. We use the
version to identify each time that we do a change. Each version is
-associated with a series of fields saved. The save_state always saves
-the state as the newer version. But load_state sometimes is able to
+associated with a series of fields saved. The `save_state` always saves
+the state as the newer version. But `load_state` sometimes is able to
load state from an older version.
-=== Legacy way ===
+Legacy way
+----------
This way is going to disappear as soon as all current users are ported to VMSTATE.
Each device has to register two functions, one to save the state and
another to load the state back.
-int register_savevm(DeviceState *dev,
- const char *idstr,
- int instance_id,
- int version_id,
- SaveStateHandler *save_state,
- LoadStateHandler *load_state,
- void *opaque);
+.. code:: c
-typedef void SaveStateHandler(QEMUFile *f, void *opaque);
-typedef int LoadStateHandler(QEMUFile *f, void *opaque, int version_id);
+ int register_savevm(DeviceState *dev,
+ const char *idstr,
+ int instance_id,
+ int version_id,
+ SaveStateHandler *save_state,
+ LoadStateHandler *load_state,
+ void *opaque);
-The important functions for the device state format are the save_state
-and load_state. Notice that load_state receives a version_id
-parameter to know what state format is receiving. save_state doesn't
+ typedef void SaveStateHandler(QEMUFile *f, void *opaque);
+ typedef int LoadStateHandler(QEMUFile *f, void *opaque, int version_id);
+
+The important functions for the device state format are the `save_state`
+and `load_state`. Notice that `load_state` receives a version_id
+parameter to know what state format is receiving. `save_state` doesn't
have a version_id parameter because it always uses the latest version.
-=== VMState ===
+VMState
+-------
The legacy way of saving/loading state of the device had the problem
that we have to maintain two functions in sync. If we did one change
@@ -135,31 +114,36 @@ save/load functions.
An example (from hw/input/pckbd.c)
-static const VMStateDescription vmstate_kbd = {
- .name = "pckbd",
- .version_id = 3,
- .minimum_version_id = 3,
- .fields = (VMStateField[]) {
- VMSTATE_UINT8(write_cmd, KBDState),
- VMSTATE_UINT8(status, KBDState),
- VMSTATE_UINT8(mode, KBDState),
- VMSTATE_UINT8(pending, KBDState),
- VMSTATE_END_OF_LIST()
- }
-};
+.. code:: c
+
+ static const VMStateDescription vmstate_kbd = {
+ .name = "pckbd",
+ .version_id = 3,
+ .minimum_version_id = 3,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT8(write_cmd, KBDState),
+ VMSTATE_UINT8(status, KBDState),
+ VMSTATE_UINT8(mode, KBDState),
+ VMSTATE_UINT8(pending, KBDState),
+ VMSTATE_END_OF_LIST()
+ }
+ };
We are declaring the state with name "pckbd".
-The version_id is 3, and the fields are 4 uint8_t in a KBDState structure.
+The `version_id` is 3, and the fields are 4 uint8_t in a KBDState structure.
We registered this with:
+.. code:: c
+
vmstate_register(NULL, 0, &vmstate_kbd, s);
Note: talk about how vmstate <-> qdev interact, and what the instance ids mean.
-You can search for VMSTATE_* macros for lots of types used in QEMU in
+You can search for ``VMSTATE_*`` macros for lots of types used in QEMU in
include/hw/hw.h.
-=== More about versions ===
+More about versions
+-------------------
Version numbers are intended for major incompatible changes to the
migration of a device, and using them breaks backwards-migration
@@ -168,22 +152,23 @@ compatibility; in general most changes can be made by adding Subsections
You can see that there are several version fields:
-- version_id: the maximum version_id supported by VMState for that device.
-- minimum_version_id: the minimum version_id that VMState is able to understand
+- `version_id`: the maximum version_id supported by VMState for that device.
+- `minimum_version_id`: the minimum version_id that VMState is able to understand
for that device.
-- minimum_version_id_old: For devices that were not able to port to vmstate, we can
+- `minimum_version_id_old`: For devices that were not able to port to vmstate, we can
assign a function that knows how to read this old state. This field is
- ignored if there is no load_state_old handler.
+ ignored if there is no `load_state_old` handler.
So, VMState is able to read versions from minimum_version_id to
-version_id. And the function load_state_old() (if present) is able to
+version_id. And the function ``load_state_old()`` (if present) is able to
load state from minimum_version_id_old to minimum_version_id. This
function is deprecated and will be removed when no more users are left.
Saving state will always create a section with the 'version_id' value
and thus can't be loaded by any older QEMU.
-=== Massaging functions ===
+Massaging functions
+-------------------
Sometimes, it is not enough to be able to save the state directly
from one structure, we need to fill the correct values there. One
@@ -194,24 +179,24 @@ load the state for the cpu that we have just loaded from the QEMUFile.
The functions to do that are inside a vmstate definition, and are called:
-- int (*pre_load)(void *opaque);
+- ``int (*pre_load)(void *opaque);``
This function is called before we load the state of one device.
-- int (*post_load)(void *opaque, int version_id);
+- ``int (*post_load)(void *opaque, int version_id);``
This function is called after we load the state of one device.
-- int (*pre_save)(void *opaque);
+- ``int (*pre_save)(void *opaque);``
This function is called before we save the state of one device.
Example: You can look at hpet.c, that uses the three function to
- massage the state that is transferred.
+massage the state that is transferred.
If you use memory API functions that update memory layout outside
initialization (i.e., in response to a guest action), this is a strong
-indication that you need to call these functions in a post_load callback.
+indication that you need to call these functions in a `post_load` callback.
Examples of such memory API functions are:
- memory_region_add_subregion()
@@ -221,7 +206,8 @@ Examples of such memory API functions are:
- memory_region_set_address()
- memory_region_set_alias_offset()
-=== Subsections ===
+Subsections
+-----------
The use of version_id allows to be able to migrate from older versions
to newer versions of a device. But not the other way around. This
@@ -251,52 +237,54 @@ value that it uses.
Example:
-static bool ide_drive_pio_state_needed(void *opaque)
-{
- IDEState *s = opaque;
+.. code:: c
- return ((s->status & DRQ_STAT) != 0)
- || (s->bus->error_status & BM_STATUS_PIO_RETRY);
-}
+ static bool ide_drive_pio_state_needed(void *opaque)
+ {
+ IDEState *s = opaque;
-const VMStateDescription vmstate_ide_drive_pio_state = {
- .name = "ide_drive/pio_state",
- .version_id = 1,
- .minimum_version_id = 1,
- .pre_save = ide_drive_pio_pre_save,
- .post_load = ide_drive_pio_post_load,
- .needed = ide_drive_pio_state_needed,
- .fields = (VMStateField[]) {
- VMSTATE_INT32(req_nb_sectors, IDEState),
- VMSTATE_VARRAY_INT32(io_buffer, IDEState, io_buffer_total_len, 1,
- vmstate_info_uint8, uint8_t),
- VMSTATE_INT32(cur_io_buffer_offset, IDEState),
- VMSTATE_INT32(cur_io_buffer_len, IDEState),
- VMSTATE_UINT8(end_transfer_fn_idx, IDEState),
- VMSTATE_INT32(elementary_transfer_size, IDEState),
- VMSTATE_INT32(packet_transfer_size, IDEState),
- VMSTATE_END_OF_LIST()
- }
-};
+ return ((s->status & DRQ_STAT) != 0)
+ || (s->bus->error_status & BM_STATUS_PIO_RETRY);
+ }
-const VMStateDescription vmstate_ide_drive = {
- .name = "ide_drive",
- .version_id = 3,
- .minimum_version_id = 0,
- .post_load = ide_drive_post_load,
- .fields = (VMStateField[]) {
- .... several fields ....
- VMSTATE_END_OF_LIST()
- },
- .subsections = (const VMStateDescription*[]) {
- &vmstate_ide_drive_pio_state,
- NULL
- }
-};
+ const VMStateDescription vmstate_ide_drive_pio_state = {
+ .name = "ide_drive/pio_state",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .pre_save = ide_drive_pio_pre_save,
+ .post_load = ide_drive_pio_post_load,
+ .needed = ide_drive_pio_state_needed,
+ .fields = (VMStateField[]) {
+ VMSTATE_INT32(req_nb_sectors, IDEState),
+ VMSTATE_VARRAY_INT32(io_buffer, IDEState, io_buffer_total_len, 1,
+ vmstate_info_uint8, uint8_t),
+ VMSTATE_INT32(cur_io_buffer_offset, IDEState),
+ VMSTATE_INT32(cur_io_buffer_len, IDEState),
+ VMSTATE_UINT8(end_transfer_fn_idx, IDEState),
+ VMSTATE_INT32(elementary_transfer_size, IDEState),
+ VMSTATE_INT32(packet_transfer_size, IDEState),
+ VMSTATE_END_OF_LIST()
+ }
+ };
+
+ const VMStateDescription vmstate_ide_drive = {
+ .name = "ide_drive",
+ .version_id = 3,
+ .minimum_version_id = 0,
+ .post_load = ide_drive_post_load,
+ .fields = (VMStateField[]) {
+ .... several fields ....
+ VMSTATE_END_OF_LIST()
+ },
+ .subsections = (const VMStateDescription*[]) {
+ &vmstate_ide_drive_pio_state,
+ NULL
+ }
+ };
Here we have a subsection for the pio state. We only need to
save/send this state when we are in the middle of a pio operation
-(that is what ide_drive_pio_state_needed() checks). If DRQ_STAT is
+(that is what ``ide_drive_pio_state_needed()`` checks). If DRQ_STAT is
not enabled, the values on that fields are garbage and don't need to
be sent.
@@ -304,11 +292,12 @@ Using a condition function that checks a 'property' to determine whether
to send a subsection allows backwards migration compatibility when
new subsections are added.
-For example;
- a) Add a new property using DEFINE_PROP_BOOL - e.g. support-foo and
+For example:
+
+ a) Add a new property using ``DEFINE_PROP_BOOL`` - e.g. support-foo and
default it to true.
- b) Add an entry to the HW_COMPAT_ for the previous version
- that sets the property to false.
+ b) Add an entry to the ``HW_COMPAT_`` for the previous version that sets
+ the property to false.
c) Add a static bool support_foo function that tests the property.
d) Add a subsection with a .needed set to the support_foo function
e) (potentially) Add a pre_load that sets up a default value for 'foo'
@@ -332,25 +321,30 @@ in most cases. In general the preference is to tie the subsection to
the machine type, and allow reliable migrations, unless the behaviour
from omission of the subsection is really bad.
-= Not sending existing elements =
+Not sending existing elements
+-----------------------------
-Sometimes members of the VMState are no longer needed;
- removing them will break migration compatibility
- making them version dependent and bumping the version will break backwards
- migration compatibility.
+Sometimes members of the VMState are no longer needed:
+
+ - removing them will break migration compatibility
+
+ - making them version dependent and bumping the version will break backwards migration compatibility.
The best way is to:
- a) Add a new property/compatibility/function in the same way for subsections
- above.
+
+ a) Add a new property/compatibility/function in the same way for subsections above.
b) replace the VMSTATE macro with the _TEST version of the macro, e.g.:
- VMSTATE_UINT32(foo, barstruct)
+
+ ``VMSTATE_UINT32(foo, barstruct)``
+
becomes
- VMSTATE_UINT32_TEST(foo, barstruct, pre_version_baz)
- Sometime in the future when we no longer care about the ancient
-versions these can be killed off.
+ ``VMSTATE_UINT32_TEST(foo, barstruct, pre_version_baz)``
-= Return path =
+ Sometime in the future when we no longer care about the ancient versions these can be killed off.
+
+Return path
+-----------
In most migration scenarios there is only a single data path that runs
from the source VM to the destination, typically along a single fd (although
@@ -360,19 +354,23 @@ However, some uses need two way communication; in particular the Postcopy
destination needs to be able to request pages on demand from the source.
For these scenarios there is a 'return path' from the destination to the source;
-qemu_file_get_return_path(QEMUFile* fwdpath) gives the QEMUFile* for the return
+``qemu_file_get_return_path(QEMUFile* fwdpath)`` gives the QEMUFile* for the return
path.
Source side
+
Forward path - written by migration thread
Return path - opened by main thread, read by return-path thread
Destination side
+
Forward path - read by main thread
Return path - opened by main thread, written by main thread AND postcopy
- thread (protected by rp_mutex)
+ thread (protected by rp_mutex)
+
+Postcopy
+========
-= Postcopy =
'Postcopy' migration is a way to deal with migrations that refuse to converge
(or take too long to converge) its plus side is that there is an upper bound on
the amount of migration traffic and time it takes, the down side is that during
@@ -386,27 +384,30 @@ a fault that's translated by QEMU into a request to the source QEMU.
Postcopy can be combined with precopy (i.e. normal migration) so that if precopy
doesn't finish in a given time the switch is made to postcopy.
-=== Enabling postcopy ===
+Enabling postcopy
+-----------------
To enable postcopy, issue this command on the monitor prior to the
start of migration:
-migrate_set_capability postcopy-ram on
+``migrate_set_capability postcopy-ram on``
The normal commands are then used to start a migration, which is still
started in precopy mode. Issuing:
-migrate_start_postcopy
+``migrate_start_postcopy``
will now cause the transition from precopy to postcopy.
It can be issued immediately after migration is started or any
time later on. Issuing it after the end of a migration is harmless.
-Note: During the postcopy phase, the bandwidth limits set using
-migrate_set_speed is ignored (to avoid delaying requested pages that
-the destination is waiting for).
+.. note::
+ During the postcopy phase, the bandwidth limits set using
+ ``migrate_set_speed`` is ignored (to avoid delaying requested pages that
+ the destination is waiting for).
-=== Postcopy device transfer ===
+Postcopy device transfer
+------------------------
Loading of device data may cause the device emulation to access guest RAM
that may trigger faults that have to be resolved by the source, as such
@@ -416,6 +417,7 @@ before the device load begins to free the stream up. This is achieved by
'packaging' the device data into a blob that's read in one go.
Source behaviour
+----------------
Until postcopy is entered the migration stream is identical to normal
precopy, except for the addition of a 'postcopy advise' command at
@@ -423,13 +425,14 @@ the beginning, to tell the destination that postcopy might happen.
When postcopy starts the source sends the page discard data and then
forms the 'package' containing:
- Command: 'postcopy listen'
- The device state
- A series of sections, identical to the precopy streams device state stream
- containing everything except postcopiable devices (i.e. RAM)
- Command: 'postcopy run'
+ - Command: 'postcopy listen'
+ - The device state
-The 'package' is sent as the data part of a Command: 'CMD_PACKAGED', and the
+ A series of sections, identical to the precopy streams device state stream
+ containing everything except postcopiable devices (i.e. RAM)
+ - Command: 'postcopy run'
+
+The 'package' is sent as the data part of a Command: ``CMD_PACKAGED``, and the
contents are formatted in the same way as the main migration stream.
During postcopy the source scans the list of dirty pages and sends them
@@ -441,82 +444,100 @@ to be sent quickly in the hope that those pages are likely to be used
by the destination soon.
Destination behaviour
+---------------------
Initially the destination looks the same as precopy, with a single thread
reading the migration stream; the 'postcopy advise' and 'discard' commands
are processed to change the way RAM is managed, but don't affect the stream
processing.
-------------------------------------------------------------------------------
- 1 2 3 4 5 6 7
-main -----DISCARD-CMD_PACKAGED ( LISTEN DEVICE DEVICE DEVICE RUN )
-thread | |
- | (page request)
- | \___
- v \
-listen thread: --- page -- page -- page -- page -- page --
-
- a b c
-------------------------------------------------------------------------------
-
-On receipt of CMD_PACKAGED (1)
- All the data associated with the package - the ( ... ) section in the
-diagram - is read into memory, and the main thread recurses into
-qemu_loadvm_state_main to process the contents of the package (2)
-which contains commands (3,6) and devices (4...)
-
-On receipt of 'postcopy listen' - 3 -(i.e. the 1st command in the package)
-a new thread (a) is started that takes over servicing the migration stream,
-while the main thread carries on loading the package. It loads normal
-background page data (b) but if during a device load a fault happens (5) the
-returned page (c) is loaded by the listen thread allowing the main threads
-device load to carry on.
-
-The last thing in the CMD_PACKAGED is a 'RUN' command (6) letting the destination
-CPUs start running.
-At the end of the CMD_PACKAGED (7) the main thread returns to normal running behaviour
-and is no longer used by migration, while the listen thread carries
-on servicing page data until the end of migration.
-
-=== Postcopy states ===
+::
+
+ ------------------------------------------------------------------------------
+ 1 2 3 4 5 6 7
+ main -----DISCARD-CMD_PACKAGED ( LISTEN DEVICE DEVICE DEVICE RUN )
+ thread | |
+ | (page request)
+ | \___
+ v \
+ listen thread: --- page -- page -- page -- page -- page --
+
+ a b c
+ ------------------------------------------------------------------------------
+
+- On receipt of ``CMD_PACKAGED`` (1)
+
+ All the data associated with the package - the ( ... ) section in the diagram -
+ is read into memory, and the main thread recurses into qemu_loadvm_state_main
+ to process the contents of the package (2) which contains commands (3,6) and
+ devices (4...)
+
+- On receipt of 'postcopy listen' - 3 -(i.e. the 1st command in the package)
+
+ a new thread (a) is started that takes over servicing the migration stream,
+ while the main thread carries on loading the package. It loads normal
+ background page data (b) but if during a device load a fault happens (5)
+ the returned page (c) is loaded by the listen thread allowing the main
+ threads device load to carry on.
+
+- The last thing in the ``CMD_PACKAGED`` is a 'RUN' command (6)
+
+ letting the destination CPUs start running. At the end of the
+ ``CMD_PACKAGED`` (7) the main thread returns to normal running behaviour and
+ is no longer used by migration, while the listen thread carries on servicing
+ page data until the end of migration.
+
+Postcopy states
+---------------
Postcopy moves through a series of states (see postcopy_state) from
ADVISE->DISCARD->LISTEN->RUNNING->END
- Advise: Set at the start of migration if postcopy is enabled, even
- if it hasn't had the start command; here the destination
- checks that its OS has the support needed for postcopy, and performs
- setup to ensure the RAM mappings are suitable for later postcopy.
- The destination will fail early in migration at this point if the
- required OS support is not present.
- (Triggered by reception of POSTCOPY_ADVISE command)
-
- Discard: Entered on receipt of the first 'discard' command; prior to
- the first Discard being performed, hugepages are switched off
- (using madvise) to ensure that no new huge pages are created
- during the postcopy phase, and to cause any huge pages that
- have discards on them to be broken.
-
- Listen: The first command in the package, POSTCOPY_LISTEN, switches
- the destination state to Listen, and starts a new thread
- (the 'listen thread') which takes over the job of receiving
- pages off the migration stream, while the main thread carries
- on processing the blob. With this thread able to process page
- reception, the destination now 'sensitises' the RAM to detect
- any access to missing pages (on Linux using the 'userfault'
- system).
-
- Running: POSTCOPY_RUN causes the destination to synchronise all
- state and start the CPUs and IO devices running. The main
- thread now finishes processing the migration package and
- now carries on as it would for normal precopy migration
- (although it can't do the cleanup it would do as it
- finishes a normal migration).
-
- End: The listen thread can now quit, and perform the cleanup of migration
- state, the migration is now complete.
-
-=== Source side page maps ===
+ - Advise
+
+ Set at the start of migration if postcopy is enabled, even
+ if it hasn't had the start command; here the destination
+ checks that its OS has the support needed for postcopy, and performs
+ setup to ensure the RAM mappings are suitable for later postcopy.
+ The destination will fail early in migration at this point if the
+ required OS support is not present.
+ (Triggered by reception of POSTCOPY_ADVISE command)
+
+ - Discard
+
+ Entered on receipt of the first 'discard' command; prior to
+ the first Discard being performed, hugepages are switched off
+ (using madvise) to ensure that no new huge pages are created
+ during the postcopy phase, and to cause any huge pages that
+ have discards on them to be broken.
+
+ - Listen
+
+ The first command in the package, POSTCOPY_LISTEN, switches
+ the destination state to Listen, and starts a new thread
+ (the 'listen thread') which takes over the job of receiving
+ pages off the migration stream, while the main thread carries
+ on processing the blob. With this thread able to process page
+ reception, the destination now 'sensitises' the RAM to detect
+ any access to missing pages (on Linux using the 'userfault'
+ system).
+
+ - Running
+
+ POSTCOPY_RUN causes the destination to synchronise all
+ state and start the CPUs and IO devices running. The main
+ thread now finishes processing the migration package and
+ now carries on as it would for normal precopy migration
+ (although it can't do the cleanup it would do as it
+ finishes a normal migration).
+
+ - End
+
+ The listen thread can now quit, and perform the cleanup of migration
+ state, the migration is now complete.
+
+Source side page maps
+---------------------
The source side keeps two bitmaps during postcopy; 'the migration bitmap'
and 'unsent map'. The 'migration bitmap' is basically the same as in
@@ -529,6 +550,7 @@ The 'unsent map' is used for the transition to postcopy. It is a bitmap that
has a bit cleared whenever a page is sent to the destination, however during
the transition to postcopy mode it is combined with the migration bitmap
to form a set of pages that:
+
a) Have been sent but then redirtied (which must be discarded)
b) Have not yet been sent - which also must be discarded to cause any
transparent huge pages built during precopy to be broken.
@@ -540,15 +562,17 @@ request for a page that has already been sent is ignored. Duplicate requests
such as this can happen as a page is sent at about the same time the
destination accesses it.
-=== Postcopy with hugepages ===
+Postcopy with hugepages
+-----------------------
Postcopy now works with hugetlbfs backed memory:
+
a) The linux kernel on the destination must support userfault on hugepages.
b) The huge-page configuration on the source and destination VMs must be
identical; i.e. RAMBlocks on both sides must use the same page size.
- c) Note that -mem-path /dev/hugepages will fall back to allocating normal
+ c) Note that ``-mem-path /dev/hugepages`` will fall back to allocating normal
RAM if it doesn't have enough hugepages, triggering (b) to fail.
- Using -mem-prealloc enforces the allocation using hugepages.
+ Using ``-mem-prealloc`` enforces the allocation using hugepages.
d) Care should be taken with the size of hugepage used; postcopy with 2MB
hugepages works well, however 1GB hugepages are likely to be problematic
since it takes ~1 second to transfer a 1GB hugepage across a 10Gbps link,
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 05/14] migration: free result string
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (3 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 04/14] docs: Convert migration.txt to rst Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 06/14] migration: fix analyze-migration.py script with radix table Juan Quintela
` (10 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reported-by: Peter Xu <peterx@redhat.com>
---
tests/migration-test.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/tests/migration-test.c b/tests/migration-test.c
index be598d3257..799e24ebc6 100644
--- a/tests/migration-test.c
+++ b/tests/migration-test.c
@@ -358,13 +358,14 @@ static void migrate_check_parameter(QTestState *who, const char *parameter,
const char *value)
{
QDict *rsp, *rsp_return;
- const char *result;
+ char *result;
rsp = wait_command(who, "{ 'execute': 'query-migrate-parameters' }");
rsp_return = qdict_get_qdict(rsp, "return");
result = g_strdup_printf("%" PRId64,
qdict_get_try_int(rsp_return, parameter, -1));
g_assert_cmpstr(result, ==, value);
+ g_free(result);
QDECREF(rsp);
}
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 06/14] migration: fix analyze-migration.py script with radix table
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (4 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 05/14] migration: free result string Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 07/14] migration: introduce postcopy-blocktime capability Juan Quintela
` (9 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx
From: Laurent Vivier <lvivier@redhat.com>
Since commit 3a38429748 ("Add a "no HPT" encoding to HTAB migration stream")
the HTAB migration stream contains a header set to "-1", meaning there
is no HPT. Teach analyze-migration.py to ignore the section in this case.
Without this fix, the script fails with a dump from a POWER9 guest:
Traceback (most recent call last):
File "./qemu/scripts/analyze-migration.py", line 602, in <module>
dump.read(dump_memory = args.memory)
File "./qemu/scripts/analyze-migration.py", line 539, in read
section.read()
File "./qemu/scripts/analyze-migration.py", line 250, in read
self.file.readvar(n_valid * self.HASH_PTE_SIZE_64)
File "./qemu/scripts/analyze-migration.py", line 64, in readvar
raise Exception("Unexpected end of %s at 0x%x" % (self.filename, self.file.tell()))
Exception: Unexpected end of migrate.dump at 0x1d4763ba
Fixes: 3a38429748 ("Add a "no HPT" encoding to HTAB migration stream")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
scripts/analyze-migration.py | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/scripts/analyze-migration.py b/scripts/analyze-migration.py
index 14553876a2..88ff4adb30 100755
--- a/scripts/analyze-migration.py
+++ b/scripts/analyze-migration.py
@@ -234,6 +234,10 @@ class HTABSection(object):
header = self.file.read32()
+ if (header == -1):
+ # "no HPT" encoding
+ return
+
if (header > 0):
# First section, just the hash shift
return
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 07/14] migration: introduce postcopy-blocktime capability
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (5 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 06/14] migration: fix analyze-migration.py script with radix table Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 08/14] migration: add postcopy blocktime ctx into MigrationIncomingState Juan Quintela
` (8 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx, Alexey Perevalov
From: Alexey Perevalov <a.perevalov@samsung.com>
Right now it could be used on destination side to
enable vCPU blocktime calculation for postcopy live migration.
vCPU blocktime - it's time since vCPU thread was put into
interruptible sleep, till memory page was copied and thread awake.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
migration/migration.c | 9 +++++++++
migration/migration.h | 1 +
qapi/migration.json | 6 +++++-
3 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/migration/migration.c b/migration/migration.c
index 19917a4b5b..fb876e9fca 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1499,6 +1499,15 @@ bool migrate_zero_blocks(void)
return s->enabled_capabilities[MIGRATION_CAPABILITY_ZERO_BLOCKS];
}
+bool migrate_postcopy_blocktime(void)
+{
+ MigrationState *s;
+
+ s = migrate_get_current();
+
+ return s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_BLOCKTIME];
+}
+
bool migrate_use_compression(void)
{
MigrationState *s;
diff --git a/migration/migration.h b/migration/migration.h
index 663415fe48..9ab8d07004 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -201,6 +201,7 @@ int migrate_compress_level(void);
int migrate_compress_threads(void);
int migrate_decompress_threads(void);
bool migrate_use_events(void);
+bool migrate_postcopy_blocktime(void);
/* Sending on the return path - generic and then for each message type */
void migrate_send_rp_shut(MigrationIncomingState *mis,
diff --git a/qapi/migration.json b/qapi/migration.json
index 4cd3d13158..4d8ccdf776 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -352,12 +352,16 @@
#
# @x-multifd: Use more than one fd for migration (since 2.11)
#
+# @postcopy-blocktime: Calculate downtime for postcopy live migration
+# (since 2.12)
+#
# Since: 1.2
##
{ 'enum': 'MigrationCapability',
'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks',
'compress', 'events', 'postcopy-ram', 'x-colo', 'release-ram',
- 'block', 'return-path', 'pause-before-switchover', 'x-multifd' ] }
+ 'block', 'return-path', 'pause-before-switchover', 'x-multifd',
+ 'postcopy-blocktime' ] }
##
# @MigrationCapabilityStatus:
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 08/14] migration: add postcopy blocktime ctx into MigrationIncomingState
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (6 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 07/14] migration: introduce postcopy-blocktime capability Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 09/14] migration: calculate vCPU blocktime on dst side Juan Quintela
` (7 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx, Alexey Perevalov
From: Alexey Perevalov <a.perevalov@samsung.com>
This patch adds request to kernel space for UFFD_FEATURE_THREAD_ID, in
case this feature is provided by kernel.
PostcopyBlocktimeContext is encapsulated inside postcopy-ram.c,
due to it being a postcopy-only feature.
Also it defines PostcopyBlocktimeContext's instance live time.
Information from PostcopyBlocktimeContext instance will be provided
much after postcopy migration end, instance of PostcopyBlocktimeContext
will live till QEMU exit, but part of it (vcpu_addr,
page_fault_vcpu_time) used only during calculation, will be released
when postcopy ended or failed.
To enable postcopy blocktime calculation on destination, need to
request proper compatibility (Patch for documentation will be at the
tail of the patch set).
As an example following command enable that capability, assume QEMU was
started with
-chardev socket,id=charmonitor,path=/var/lib/migrate-vm-monitor.sock
option to control it
[root@host]#printf "{\"execute\" : \"qmp_capabilities\"}\r\n \
{\"execute\": \"migrate-set-capabilities\" , \"arguments\": {
\"capabilities\": [ { \"capability\": \"postcopy-blocktime\", \"state\":
true } ] } }" | nc -U /var/lib/migrate-vm-monitor.sock
Or just with HMP
(qemu) migrate_set_capability postcopy-blocktime on
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
migration/migration.h | 8 +++++++
migration/postcopy-ram.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 67 insertions(+)
diff --git a/migration/migration.h b/migration/migration.h
index 9ab8d07004..7e06c11773 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -22,6 +22,8 @@
#include "hw/qdev.h"
#include "io/channel.h"
+struct PostcopyBlocktimeContext;
+
/* State for the incoming migration */
struct MigrationIncomingState {
QEMUFile *from_src_file;
@@ -59,6 +61,12 @@ struct MigrationIncomingState {
/* The coroutine we should enter (back) after failover */
Coroutine *migration_incoming_co;
QemuSemaphore colo_incoming_sem;
+
+ /*
+ * PostcopyBlocktimeContext to keep information for postcopy
+ * live migration, to calculate vCPU block time
+ * */
+ struct PostcopyBlocktimeContext *blocktime_ctx;
};
MigrationIncomingState *migration_incoming_get_current(void);
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index bec6c2c66b..c18ec5aa18 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -61,6 +61,52 @@ struct PostcopyDiscardState {
#include <sys/eventfd.h>
#include <linux/userfaultfd.h>
+typedef struct PostcopyBlocktimeContext {
+ /* time when page fault initiated per vCPU */
+ int64_t *page_fault_vcpu_time;
+ /* page address per vCPU */
+ uint64_t *vcpu_addr;
+ int64_t total_blocktime;
+ /* blocktime per vCPU */
+ int64_t *vcpu_blocktime;
+ /* point in time when last page fault was initiated */
+ int64_t last_begin;
+ /* number of vCPU are suspended */
+ int smp_cpus_down;
+
+ /*
+ * Handler for exit event, necessary for
+ * releasing whole blocktime_ctx
+ */
+ Notifier exit_notifier;
+} PostcopyBlocktimeContext;
+
+static void destroy_blocktime_context(struct PostcopyBlocktimeContext *ctx)
+{
+ g_free(ctx->page_fault_vcpu_time);
+ g_free(ctx->vcpu_addr);
+ g_free(ctx->vcpu_blocktime);
+ g_free(ctx);
+}
+
+static void migration_exit_cb(Notifier *n, void *data)
+{
+ PostcopyBlocktimeContext *ctx = container_of(n, PostcopyBlocktimeContext,
+ exit_notifier);
+ destroy_blocktime_context(ctx);
+}
+
+static struct PostcopyBlocktimeContext *blocktime_context_new(void)
+{
+ PostcopyBlocktimeContext *ctx = g_new0(PostcopyBlocktimeContext, 1);
+ ctx->page_fault_vcpu_time = g_new0(int64_t, smp_cpus);
+ ctx->vcpu_addr = g_new0(uint64_t, smp_cpus);
+ ctx->vcpu_blocktime = g_new0(int64_t, smp_cpus);
+
+ ctx->exit_notifier.notify = migration_exit_cb;
+ qemu_add_exit_notifier(&ctx->exit_notifier);
+ return ctx;
+}
/**
* receive_ufd_features: check userfault fd features, to request only supported
@@ -153,6 +199,19 @@ static bool ufd_check_and_apply(int ufd, MigrationIncomingState *mis)
}
}
+#ifdef UFFD_FEATURE_THREAD_ID
+ if (migrate_postcopy_blocktime() && mis &&
+ UFFD_FEATURE_THREAD_ID & supported_features) {
+ /* kernel supports that feature */
+ /* don't create blocktime_context if it exists */
+ if (!mis->blocktime_ctx) {
+ mis->blocktime_ctx = blocktime_context_new();
+ }
+
+ asked_features |= UFFD_FEATURE_THREAD_ID;
+ }
+#endif
+
/*
* request features, even if asked_features is 0, due to
* kernel expects UFFD_API before UFFDIO_REGISTER, per
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 09/14] migration: calculate vCPU blocktime on dst side
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (7 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 08/14] migration: add postcopy blocktime ctx into MigrationIncomingState Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 10/14] migration: postcopy_blocktime documentation Juan Quintela
` (6 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx, Alexey Perevalov
From: Alexey Perevalov <a.perevalov@samsung.com>
This patch provides blocktime calculation per vCPU,
as a summary and as a overlapped value for all vCPUs.
This approach was suggested by Peter Xu, as an improvements of
previous approch where QEMU kept tree with faulted page address and cpus bitmask
in it. Now QEMU is keeping array with faulted page address as value and vCPU
as index. It helps to find proper vCPU at UFFD_COPY time. Also it keeps
list for blocktime per vCPU (could be traced with page_fault_addr)
Blocktime will not calculated if postcopy_blocktime field of
MigrationIncomingState wasn't initialized.
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
migration/postcopy-ram.c | 143 ++++++++++++++++++++++++++++++++++++++++++++++-
migration/trace-events | 5 +-
2 files changed, 146 insertions(+), 2 deletions(-)
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index c18ec5aa18..6bf24e9596 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -553,6 +553,142 @@ static int ram_block_enable_notify(const char *block_name, void *host_addr,
return 0;
}
+static int get_mem_fault_cpu_index(uint32_t pid)
+{
+ CPUState *cpu_iter;
+
+ CPU_FOREACH(cpu_iter) {
+ if (cpu_iter->thread_id == pid) {
+ trace_get_mem_fault_cpu_index(cpu_iter->cpu_index, pid);
+ return cpu_iter->cpu_index;
+ }
+ }
+ trace_get_mem_fault_cpu_index(-1, pid);
+ return -1;
+}
+
+/*
+ * This function is being called when pagefault occurs. It
+ * tracks down vCPU blocking time.
+ *
+ * @addr: faulted host virtual address
+ * @ptid: faulted process thread id
+ * @rb: ramblock appropriate to addr
+ */
+static void mark_postcopy_blocktime_begin(uint64_t addr, uint32_t ptid,
+ RAMBlock *rb)
+{
+ int cpu, already_received;
+ MigrationIncomingState *mis = migration_incoming_get_current();
+ PostcopyBlocktimeContext *dc = mis->blocktime_ctx;
+ int64_t now_ms;
+
+ if (!dc || ptid == 0) {
+ return;
+ }
+ cpu = get_mem_fault_cpu_index(ptid);
+ if (cpu < 0) {
+ return;
+ }
+
+ now_ms = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
+ if (dc->vcpu_addr[cpu] == 0) {
+ atomic_inc(&dc->smp_cpus_down);
+ }
+
+ atomic_xchg__nocheck(&dc->last_begin, now_ms);
+ atomic_xchg__nocheck(&dc->page_fault_vcpu_time[cpu], now_ms);
+ atomic_xchg__nocheck(&dc->vcpu_addr[cpu], addr);
+
+ /* check it here, not at the begining of the function,
+ * due to, check could accur early than bitmap_set in
+ * qemu_ufd_copy_ioctl */
+ already_received = ramblock_recv_bitmap_test(rb, (void *)addr);
+ if (already_received) {
+ atomic_xchg__nocheck(&dc->vcpu_addr[cpu], 0);
+ atomic_xchg__nocheck(&dc->page_fault_vcpu_time[cpu], 0);
+ atomic_dec(&dc->smp_cpus_down);
+ }
+ trace_mark_postcopy_blocktime_begin(addr, dc, dc->page_fault_vcpu_time[cpu],
+ cpu, already_received);
+}
+
+/*
+ * This function just provide calculated blocktime per cpu and trace it.
+ * Total blocktime is calculated in mark_postcopy_blocktime_end.
+ *
+ *
+ * Assume we have 3 CPU
+ *
+ * S1 E1 S1 E1
+ * -----***********------------xxx***************------------------------> CPU1
+ *
+ * S2 E2
+ * ------------****************xxx---------------------------------------> CPU2
+ *
+ * S3 E3
+ * ------------------------****xxx********-------------------------------> CPU3
+ *
+ * We have sequence S1,S2,E1,S3,S1,E2,E3,E1
+ * S2,E1 - doesn't match condition due to sequence S1,S2,E1 doesn't include CPU3
+ * S3,S1,E2 - sequence includes all CPUs, in this case overlap will be S1,E2 -
+ * it's a part of total blocktime.
+ * S1 - here is last_begin
+ * Legend of the picture is following:
+ * * - means blocktime per vCPU
+ * x - means overlapped blocktime (total blocktime)
+ *
+ * @addr: host virtual address
+ */
+static void mark_postcopy_blocktime_end(uint64_t addr)
+{
+ MigrationIncomingState *mis = migration_incoming_get_current();
+ PostcopyBlocktimeContext *dc = mis->blocktime_ctx;
+ int i, affected_cpu = 0;
+ int64_t now_ms;
+ bool vcpu_total_blocktime = false;
+ int64_t read_vcpu_time;
+
+ if (!dc) {
+ return;
+ }
+
+ now_ms = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
+
+ /* lookup cpu, to clear it,
+ * that algorithm looks straighforward, but it's not
+ * optimal, more optimal algorithm is keeping tree or hash
+ * where key is address value is a list of */
+ for (i = 0; i < smp_cpus; i++) {
+ uint64_t vcpu_blocktime = 0;
+
+ read_vcpu_time = atomic_fetch_add(&dc->page_fault_vcpu_time[i], 0);
+ if (atomic_fetch_add(&dc->vcpu_addr[i], 0) != addr ||
+ read_vcpu_time == 0) {
+ continue;
+ }
+ atomic_xchg__nocheck(&dc->vcpu_addr[i], 0);
+ vcpu_blocktime = now_ms - read_vcpu_time;
+ affected_cpu += 1;
+ /* we need to know is that mark_postcopy_end was due to
+ * faulted page, another possible case it's prefetched
+ * page and in that case we shouldn't be here */
+ if (!vcpu_total_blocktime &&
+ atomic_fetch_add(&dc->smp_cpus_down, 0) == smp_cpus) {
+ vcpu_total_blocktime = true;
+ }
+ /* continue cycle, due to one page could affect several vCPUs */
+ dc->vcpu_blocktime[i] += vcpu_blocktime;
+ }
+
+ atomic_sub(&dc->smp_cpus_down, affected_cpu);
+ if (vcpu_total_blocktime) {
+ dc->total_blocktime += now_ms - atomic_fetch_add(&dc->last_begin, 0);
+ }
+ trace_mark_postcopy_blocktime_end(addr, dc, dc->total_blocktime,
+ affected_cpu);
+}
+
/*
* Handle faults detected by the USERFAULT markings
*/
@@ -630,8 +766,11 @@ static void *postcopy_ram_fault_thread(void *opaque)
rb_offset &= ~(qemu_ram_pagesize(rb) - 1);
trace_postcopy_ram_fault_thread_request(msg.arg.pagefault.address,
qemu_ram_get_idstr(rb),
- rb_offset);
+ rb_offset,
+ msg.arg.pagefault.feat.ptid);
+ mark_postcopy_blocktime_begin((uintptr_t)(msg.arg.pagefault.address),
+ msg.arg.pagefault.feat.ptid, rb);
/*
* Send the request to the source - we want to request one
* of our host page sizes (which is >= TPS)
@@ -721,6 +860,8 @@ static int qemu_ufd_copy_ioctl(int userfault_fd, void *host_addr,
if (!ret) {
ramblock_recv_bitmap_set_range(rb, host_addr,
pagesize / qemu_target_page_size());
+ mark_postcopy_blocktime_end((uint64_t)(uintptr_t)host_addr);
+
}
return ret;
}
diff --git a/migration/trace-events b/migration/trace-events
index 6f29fcc686..462d15717d 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -115,6 +115,8 @@ process_incoming_migration_co_end(int ret, int ps) "ret=%d postcopy-state=%d"
process_incoming_migration_co_postcopy_end_main(void) ""
migration_set_incoming_channel(void *ioc, const char *ioctype) "ioc=%p ioctype=%s"
migration_set_outgoing_channel(void *ioc, const char *ioctype, const char *hostname) "ioc=%p ioctype=%s hostname=%s"
+mark_postcopy_blocktime_begin(uint64_t addr, void *dd, int64_t time, int cpu, int received) "addr: 0x%" PRIx64 ", dd: %p, time: %" PRId64 ", cpu: %d, already_received: %d"
+mark_postcopy_blocktime_end(uint64_t addr, void *dd, int64_t time, int affected_cpu) "addr: 0x%" PRIx64 ", dd: %p, time: %" PRId64 ", affected_cpu: %d"
# migration/rdma.c
qemu_rdma_accept_incoming_migration(void) ""
@@ -191,7 +193,7 @@ postcopy_ram_enable_notify(void) ""
postcopy_ram_fault_thread_entry(void) ""
postcopy_ram_fault_thread_exit(void) ""
postcopy_ram_fault_thread_quit(void) ""
-postcopy_ram_fault_thread_request(uint64_t hostaddr, const char *ramblock, size_t offset) "Request for HVA=0x%" PRIx64 " rb=%s offset=0x%zx"
+postcopy_ram_fault_thread_request(uint64_t hostaddr, const char *ramblock, size_t offset, uint32_t pid) "Request for HVA=0x%" PRIx64 " rb=%s offset=0x%zx pid=%u"
postcopy_ram_incoming_cleanup_closeuf(void) ""
postcopy_ram_incoming_cleanup_entry(void) ""
postcopy_ram_incoming_cleanup_exit(void) ""
@@ -200,6 +202,7 @@ save_xbzrle_page_skipping(void) ""
save_xbzrle_page_overflow(void) ""
ram_save_iterate_big_wait(uint64_t milliconds, int iterations) "big wait: %" PRIu64 " milliseconds, %d iterations"
ram_load_complete(int ret, uint64_t seq_iter) "exit_code %d seq iteration %" PRIu64
+get_mem_fault_cpu_index(int cpu, uint32_t pid) "cpu: %d, pid: %u"
# migration/exec.c
migration_exec_outgoing(const char *cmd) "cmd=%s"
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 10/14] migration: postcopy_blocktime documentation
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (8 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 09/14] migration: calculate vCPU blocktime on dst side Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 11/14] migration: add blocktime calculation into migration-test Juan Quintela
` (5 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx, Alexey Perevalov
From: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
docs/devel/migration.rst | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst
index bf97080dac..015a9ebdf7 100644
--- a/docs/devel/migration.rst
+++ b/docs/devel/migration.rst
@@ -401,6 +401,20 @@ will now cause the transition from precopy to postcopy.
It can be issued immediately after migration is started or any
time later on. Issuing it after the end of a migration is harmless.
+Blocktime is a postcopy live migration metric, intended to show how
+long the vCPU was in state of interruptable sleep due to pagefault.
+That metric is calculated both for all vCPUs as overlapped value, and
+separately for each vCPU. These values are calculated on destination
+side. To enable postcopy blocktime calculation, enter following
+command on destination monitor:
+
+``migrate_set_capability postcopy-blocktime on``
+
+Postcopy blocktime can be retrieved by query-migrate qmp command.
+postcopy-blocktime value of qmp command will show overlapped blocking
+time for all vCPU, postcopy-vcpu-blocktime will show list of blocking
+time per vCPU.
+
.. note::
During the postcopy phase, the bandwidth limits set using
``migrate_set_speed`` is ignored (to avoid delaying requested pages that
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 11/14] migration: add blocktime calculation into migration-test
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (9 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 10/14] migration: postcopy_blocktime documentation Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 12/14] migration: add postcopy total blocktime into query-migrate Juan Quintela
` (4 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx, Alexey Perevalov
From: Alexey Perevalov <a.perevalov@samsung.com>
This patch just requests blocktime calculation,
and check it in case when UFFD_FEATURE_THREAD_ID feature is set
on the host.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
tests/migration-test.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/tests/migration-test.c b/tests/migration-test.c
index 799e24ebc6..9fd5dadc0d 100644
--- a/tests/migration-test.c
+++ b/tests/migration-test.c
@@ -25,6 +25,7 @@
const unsigned start_address = 1024 * 1024;
const unsigned end_address = 100 * 1024 * 1024;
bool got_stop;
+static bool uffd_feature_thread_id;
#if defined(__linux__)
#include <sys/syscall.h>
@@ -54,6 +55,7 @@ static bool ufd_version_check(void)
g_test_message("Skipping test: UFFDIO_API failed");
return false;
}
+ uffd_feature_thread_id = api_struct.features & UFFD_FEATURE_THREAD_ID;
ioctl_mask = (__u64)1 << _UFFDIO_REGISTER |
(__u64)1 << _UFFDIO_UNREGISTER;
@@ -266,6 +268,16 @@ static uint64_t get_migration_pass(QTestState *who)
return result;
}
+static void read_blocktime(QTestState *who)
+{
+ QDict *rsp, *rsp_return;
+
+ rsp = wait_command(who, "{ 'execute': 'query-migrate' }");
+ rsp_return = qdict_get_qdict(rsp, "return");
+ g_assert(qdict_haskey(rsp_return, "postcopy-blocktime"));
+ QDECREF(rsp);
+}
+
static void wait_for_migration_complete(QTestState *who)
{
QDict *rsp, *rsp_return;
@@ -525,6 +537,7 @@ static void test_migrate(void)
migrate_set_capability(from, "postcopy-ram", "true");
migrate_set_capability(to, "postcopy-ram", "true");
+ migrate_set_capability(to, "postcopy-blocktime", "true");
/* We want to pick a speed slow enough that the test completes
* quickly, but that it doesn't complete precopy even on a slow
@@ -553,6 +566,9 @@ static void test_migrate(void)
wait_for_serial("dest_serial");
wait_for_migration_complete(from);
+ if (uffd_feature_thread_id) {
+ read_blocktime(to);
+ }
g_free(uri);
test_migrate_end(from, to);
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 12/14] migration: add postcopy total blocktime into query-migrate
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (10 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 11/14] migration: add blocktime calculation into migration-test Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 13/14] migration: Guard ram_bytes_remaining against early call Juan Quintela
` (3 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx, Alexey Perevalov
From: Alexey Perevalov <a.perevalov@samsung.com>
Postcopy total blocktime is available on destination side only.
But query-migrate was possible only for source. This patch
adds ability to call query-migrate on destination.
To be able to see postcopy blocktime, need to request postcopy-blocktime
capability.
The query-migrate command will show following sample result:
{"return":
"postcopy-vcpu-blocktime": [115, 100],
"status": "completed",
"postcopy-blocktime": 100
}}
postcopy_vcpu_blocktime contains list, where the first item is the first
vCPU in QEMU.
This patch has a drawback, it combines states of incoming and
outgoing migration. Ongoing migration state will overwrite incoming
state. Looks like better to separate query-migrate for incoming and
outgoing migration or add parameter to indicate type of migration.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
hmp.c | 15 +++++++++++++
migration/migration.c | 42 ++++++++++++++++++++++++++++++++----
migration/migration.h | 4 ++++
migration/postcopy-ram.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++
migration/trace-events | 1 +
qapi/migration.json | 11 +++++++++-
6 files changed, 124 insertions(+), 5 deletions(-)
diff --git a/hmp.c b/hmp.c
index 1727c9c003..354baaa6b6 100644
--- a/hmp.c
+++ b/hmp.c
@@ -264,6 +264,21 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
info->cpu_throttle_percentage);
}
+ if (info->has_postcopy_blocktime) {
+ monitor_printf(mon, "postcopy blocktime: %" PRId64 "\n",
+ info->postcopy_blocktime);
+ }
+
+ if (info->has_postcopy_vcpu_blocktime) {
+ Visitor *v;
+ char *str;
+ v = string_output_visitor_new(false, &str);
+ visit_type_int64List(v, NULL, &info->postcopy_vcpu_blocktime, NULL);
+ visit_complete(v, &str);
+ monitor_printf(mon, "postcopy vcpu blocktime: %s\n", str);
+ g_free(str);
+ visit_free(v);
+ }
qapi_free_MigrationInfo(info);
qapi_free_MigrationCapabilityStatusList(caps);
}
diff --git a/migration/migration.c b/migration/migration.c
index fb876e9fca..17cc219da2 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -591,14 +591,15 @@ static void populate_disk_info(MigrationInfo *info)
}
}
-MigrationInfo *qmp_query_migrate(Error **errp)
+static void fill_source_migration_info(MigrationInfo *info)
{
- MigrationInfo *info = g_malloc0(sizeof(*info));
MigrationState *s = migrate_get_current();
switch (s->state) {
case MIGRATION_STATUS_NONE:
/* no migration has happened ever */
+ /* do not overwrite destination migration status */
+ return;
break;
case MIGRATION_STATUS_SETUP:
info->has_status = true;
@@ -649,8 +650,6 @@ MigrationInfo *qmp_query_migrate(Error **errp)
break;
}
info->status = s->state;
-
- return info;
}
/**
@@ -714,6 +713,41 @@ static bool migrate_caps_check(bool *cap_list,
return true;
}
+static void fill_destination_migration_info(MigrationInfo *info)
+{
+ MigrationIncomingState *mis = migration_incoming_get_current();
+
+ switch (mis->state) {
+ case MIGRATION_STATUS_NONE:
+ return;
+ break;
+ case MIGRATION_STATUS_SETUP:
+ case MIGRATION_STATUS_CANCELLING:
+ case MIGRATION_STATUS_CANCELLED:
+ case MIGRATION_STATUS_ACTIVE:
+ case MIGRATION_STATUS_POSTCOPY_ACTIVE:
+ case MIGRATION_STATUS_FAILED:
+ case MIGRATION_STATUS_COLO:
+ info->has_status = true;
+ break;
+ case MIGRATION_STATUS_COMPLETED:
+ info->has_status = true;
+ fill_destination_postcopy_migration_info(info);
+ break;
+ }
+ info->status = mis->state;
+}
+
+MigrationInfo *qmp_query_migrate(Error **errp)
+{
+ MigrationInfo *info = g_malloc0(sizeof(*info));
+
+ fill_destination_migration_info(info);
+ fill_source_migration_info(info);
+
+ return info;
+}
+
void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
Error **errp)
{
diff --git a/migration/migration.h b/migration/migration.h
index 7e06c11773..d84bc550b1 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -71,6 +71,10 @@ struct MigrationIncomingState {
MigrationIncomingState *migration_incoming_get_current(void);
void migration_incoming_state_destroy(void);
+/*
+ * Functions to work with blocktime context
+ */
+void fill_destination_postcopy_migration_info(MigrationInfo *info);
#define TYPE_MIGRATION "migration"
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 6bf24e9596..28231334e0 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -108,6 +108,55 @@ static struct PostcopyBlocktimeContext *blocktime_context_new(void)
return ctx;
}
+static int64List *get_vcpu_blocktime_list(PostcopyBlocktimeContext *ctx)
+{
+ int64List *list = NULL, *entry = NULL;
+ int i;
+
+ for (i = smp_cpus - 1; i >= 0; i--) {
+ entry = g_new0(int64List, 1);
+ entry->value = ctx->vcpu_blocktime[i];
+ entry->next = list;
+ list = entry;
+ }
+
+ return list;
+}
+
+/*
+ * This function just populates MigrationInfo from postcopy's
+ * blocktime context. It will not populate MigrationInfo,
+ * unless postcopy-blocktime capability was set.
+ *
+ * @info: pointer to MigrationInfo to populate
+ */
+void fill_destination_postcopy_migration_info(MigrationInfo *info)
+{
+ MigrationIncomingState *mis = migration_incoming_get_current();
+ PostcopyBlocktimeContext *bc = mis->blocktime_ctx;
+
+ if (!bc) {
+ return;
+ }
+
+ info->has_postcopy_blocktime = true;
+ info->postcopy_blocktime = bc->total_blocktime;
+ info->has_postcopy_vcpu_blocktime = true;
+ info->postcopy_vcpu_blocktime = get_vcpu_blocktime_list(bc);
+}
+
+static uint64_t get_postcopy_total_blocktime(void)
+{
+ MigrationIncomingState *mis = migration_incoming_get_current();
+ PostcopyBlocktimeContext *bc = mis->blocktime_ctx;
+
+ if (!bc) {
+ return 0;
+ }
+
+ return bc->total_blocktime;
+}
+
/**
* receive_ufd_features: check userfault fd features, to request only supported
* features in the future.
@@ -482,6 +531,9 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis)
munmap(mis->postcopy_tmp_zero_page, mis->largest_page_size);
mis->postcopy_tmp_zero_page = NULL;
}
+ trace_postcopy_ram_incoming_cleanup_blocktime(
+ get_postcopy_total_blocktime());
+
trace_postcopy_ram_incoming_cleanup_exit();
return 0;
}
@@ -959,6 +1011,10 @@ void *postcopy_get_tmp_page(MigrationIncomingState *mis)
#else
/* No target OS support, stubs just fail */
+void fill_destination_postcopy_migration_info(MigrationInfo *info)
+{
+}
+
bool postcopy_ram_supported_by_host(MigrationIncomingState *mis)
{
error_report("%s: No OS support", __func__);
diff --git a/migration/trace-events b/migration/trace-events
index 462d15717d..141e773305 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -198,6 +198,7 @@ postcopy_ram_incoming_cleanup_closeuf(void) ""
postcopy_ram_incoming_cleanup_entry(void) ""
postcopy_ram_incoming_cleanup_exit(void) ""
postcopy_ram_incoming_cleanup_join(void) ""
+postcopy_ram_incoming_cleanup_blocktime(uint64_t total) "total blocktime %" PRIu64
save_xbzrle_page_skipping(void) ""
save_xbzrle_page_overflow(void) ""
ram_save_iterate_big_wait(uint64_t milliconds, int iterations) "big wait: %" PRIu64 " milliseconds, %d iterations"
diff --git a/qapi/migration.json b/qapi/migration.json
index 4d8ccdf776..70e7b677ef 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -155,6 +155,13 @@
# @error-desc: the human readable error description string, when
# @status is 'failed'. 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 (Since 2.12)
+#
+# @postcopy-vcpu-blocktime: list of the postcopy blocktime per vCPU (Since 2.12)
+#
+
#
# Since: 0.14.0
##
@@ -167,7 +174,9 @@
'*downtime': 'int',
'*setup-time': 'int',
'*cpu-throttle-percentage': 'int',
- '*error-desc': 'str'} }
+ '*error-desc': 'str',
+ '*postcopy-blocktime' : 'int64',
+ '*postcopy-vcpu-blocktime': ['int64']} }
##
# @query-migrate:
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 13/14] migration: Guard ram_bytes_remaining against early call
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (11 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 12/14] migration: add postcopy total blocktime into query-migrate Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-03 9:38 ` [Qemu-devel] [PULL 14/14] migration: finalize current_migration object Juan Quintela
` (2 subsequent siblings)
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Calling ram_bytes_remaining during the early part of setup is unsafe
because the ram_state isn't yet initialised.
This can happen in the sequence:
migrate
migrate_cancel
info migrate
if the migrate sticks trying to connect (e.g. to an unresponsive
destination due to the connect timeout). Here 'info migrate' sees
a state of CANCELLING and so assumes the migrate has partially happened.
partial fix for:
RH bz: https://bugzilla.redhat.com/show_bug.cgi?id=1525899
Reported-by: Xianxian Wang <xianwang@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
migration/ram.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/migration/ram.c b/migration/ram.c
index 021d583b9b..cb1950f3eb 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -237,7 +237,8 @@ static RAMState *ram_state;
uint64_t ram_bytes_remaining(void)
{
- return ram_state->migration_dirty_pages * TARGET_PAGE_SIZE;
+ return ram_state ? (ram_state->migration_dirty_pages * TARGET_PAGE_SIZE) :
+ 0;
}
MigrationStats ram_counters;
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* [Qemu-devel] [PULL 14/14] migration: finalize current_migration object
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (12 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 13/14] migration: Guard ram_bytes_remaining against early call Juan Quintela
@ 2018-01-03 9:38 ` Juan Quintela
2018-01-05 0:30 ` [Qemu-devel] [PULL 00/14] Migration pull request Eric Blake
2018-01-11 11:51 ` Peter Maydell
15 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-03 9:38 UTC (permalink / raw)
To: qemu-devel; +Cc: dgilbert, lvivier, peterx, Vladimir Sementsov-Ogievskiy
From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
current_migration has .instance_finalize callback, but it is not
called, because nobody unrefs current_migration. Fix that.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
include/migration/misc.h | 1 +
migration/migration.c | 5 +++++
vl.c | 1 +
3 files changed, 7 insertions(+)
diff --git a/include/migration/misc.h b/include/migration/misc.h
index c079b7771b..77fd4f587c 100644
--- a/include/migration/misc.h
+++ b/include/migration/misc.h
@@ -44,6 +44,7 @@ void dump_vmstate_json_to_file(FILE *out_fp);
/* migration/migration.c */
void migration_object_init(void);
+void migration_object_finalize(void);
void qemu_start_incoming_migration(const char *uri, Error **errp);
bool migration_is_idle(void);
void add_migration_state_change_notifier(Notifier *notify);
diff --git a/migration/migration.c b/migration/migration.c
index 17cc219da2..7a77b193c1 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -132,6 +132,11 @@ void migration_object_init(void)
}
}
+void migration_object_finalize(void)
+{
+ object_unref(OBJECT(current_migration));
+}
+
/* For outgoing */
MigrationState *migrate_get_current(void)
{
diff --git a/vl.c b/vl.c
index d3a5c5d021..073aef4b84 100644
--- a/vl.c
+++ b/vl.c
@@ -4874,6 +4874,7 @@ int main(int argc, char **argv, char **envp)
monitor_cleanup();
qemu_chr_cleanup();
user_creatable_cleanup();
+ migration_object_finalize();
/* TODO: unref root container, check all devices are ok */
return 0;
--
2.14.3
^ permalink raw reply related [flat|nested] 22+ messages in thread* Re: [Qemu-devel] [PULL 00/14] Migration pull request
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (13 preceding siblings ...)
2018-01-03 9:38 ` [Qemu-devel] [PULL 14/14] migration: finalize current_migration object Juan Quintela
@ 2018-01-05 0:30 ` Eric Blake
2018-01-05 9:29 ` Dr. David Alan Gilbert
2018-01-05 9:59 ` Juan Quintela
2018-01-11 11:51 ` Peter Maydell
15 siblings, 2 replies; 22+ messages in thread
From: Eric Blake @ 2018-01-05 0:30 UTC (permalink / raw)
To: Juan Quintela, qemu-devel
Cc: lvivier, dgilbert, peterx, Alexey, Markus Armbruster
[-- Attachment #1: Type: text/plain, Size: 1178 bytes --]
On 01/03/2018 03:38 AM, Juan Quintela wrote:
> Hi
>
> This are the changes for migration that are already reviewed.
>
> Please, apply.
>
> Alexey Perevalov (6):
> migration: introduce postcopy-blocktime capability
> migration: add postcopy blocktime ctx into MigrationIncomingState
> migration: calculate vCPU blocktime on dst side
> migration: postcopy_blocktime documentation
> migration: add blocktime calculation into migration-test
> migration: add postcopy total blocktime into query-migrate
I had unanswered questions about these patches in the v12 series, where
I'm not sure if the interface is still quite right. We're still early
enough that we could adjust the interface after the fact depending on
how the questions are answered; but we're also early enough that it may
be smarter to get the interface right before including it in a pull
request. I'll leave it to Peter and Juan to sort out whether this means
an updated pull request is needed, or to take this as-is.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]
^ permalink raw reply [flat|nested] 22+ messages in thread* Re: [Qemu-devel] [PULL 00/14] Migration pull request
2018-01-05 0:30 ` [Qemu-devel] [PULL 00/14] Migration pull request Eric Blake
@ 2018-01-05 9:29 ` Dr. David Alan Gilbert
2018-01-05 9:59 ` Juan Quintela
1 sibling, 0 replies; 22+ messages in thread
From: Dr. David Alan Gilbert @ 2018-01-05 9:29 UTC (permalink / raw)
To: Eric Blake
Cc: Juan Quintela, qemu-devel, lvivier, peterx, Alexey,
Markus Armbruster
* Eric Blake (eblake@redhat.com) wrote:
> On 01/03/2018 03:38 AM, Juan Quintela wrote:
> > Hi
> >
> > This are the changes for migration that are already reviewed.
> >
> > Please, apply.
> >
>
> > Alexey Perevalov (6):
> > migration: introduce postcopy-blocktime capability
> > migration: add postcopy blocktime ctx into MigrationIncomingState
> > migration: calculate vCPU blocktime on dst side
> > migration: postcopy_blocktime documentation
> > migration: add blocktime calculation into migration-test
> > migration: add postcopy total blocktime into query-migrate
>
> I had unanswered questions about these patches in the v12 series, where
> I'm not sure if the interface is still quite right. We're still early
> enough that we could adjust the interface after the fact depending on
> how the questions are answered; but we're also early enough that it may
> be smarter to get the interface right before including it in a pull
> request. I'll leave it to Peter and Juan to sort out whether this means
> an updated pull request is needed, or to take this as-is.
Hadn't that discussion been done to death about 10 times during the
(long) life of this series?
Dave
> --
> Eric Blake, Principal Software Engineer
> Red Hat, Inc. +1-919-301-3266
> Virtualization: qemu.org | libvirt.org
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [Qemu-devel] [PULL 00/14] Migration pull request
2018-01-05 0:30 ` [Qemu-devel] [PULL 00/14] Migration pull request Eric Blake
2018-01-05 9:29 ` Dr. David Alan Gilbert
@ 2018-01-05 9:59 ` Juan Quintela
2018-01-09 18:24 ` Peter Maydell
2018-01-10 4:58 ` Alexey Perevalov
1 sibling, 2 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-05 9:59 UTC (permalink / raw)
To: Eric Blake
Cc: qemu-devel, lvivier, dgilbert, peterx, Alexey, Markus Armbruster
Eric Blake <eblake@redhat.com> wrote:
> On 01/03/2018 03:38 AM, Juan Quintela wrote:
>> Hi
>>
>> This are the changes for migration that are already reviewed.
>>
>> Please, apply.
>>
>
>> Alexey Perevalov (6):
>> migration: introduce postcopy-blocktime capability
>> migration: add postcopy blocktime ctx into MigrationIncomingState
>> migration: calculate vCPU blocktime on dst side
>> migration: postcopy_blocktime documentation
>> migration: add blocktime calculation into migration-test
>> migration: add postcopy total blocktime into query-migrate
>
> I had unanswered questions about these patches in the v12 series, where
> I'm not sure if the interface is still quite right.
To be fair, I had alroady integrated the patches before I saw your questions.
> We're still early
> enough that we could adjust the interface after the fact depending on
> how the questions are answered;
I think this is the best approach, so far I can see two questions:
- do we want to make it conditional? it requires some locking, but I
haven't meassured it to see how slow/fast is it.
- the other was documentation.
I will like Alexey to answer. Depending of how slow it is, I can agree
to make it non-optional.
> but we're also early enough that it may
> be smarter to get the interface right before including it in a pull
> request. I'll leave it to Peter and Juan to sort out whether this means
> an updated pull request is needed, or to take this as-is.
Thanks, Juan.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [Qemu-devel] [PULL 00/14] Migration pull request
2018-01-05 9:59 ` Juan Quintela
@ 2018-01-09 18:24 ` Peter Maydell
2018-01-09 18:28 ` Juan Quintela
2018-01-10 4:58 ` Alexey Perevalov
1 sibling, 1 reply; 22+ messages in thread
From: Peter Maydell @ 2018-01-09 18:24 UTC (permalink / raw)
To: Juan Quintela
Cc: Eric Blake, Laurent Vivier, QEMU Developers, Markus Armbruster,
Peter Xu, Alexey, Dr. David Alan Gilbert
On 5 January 2018 at 09:59, Juan Quintela <quintela@redhat.com> wrote:
> Eric Blake <eblake@redhat.com> wrote:
>> On 01/03/2018 03:38 AM, Juan Quintela wrote:
>>> Hi
>>>
>>> This are the changes for migration that are already reviewed.
>>>
>>> Please, apply.
>>>
>>
>>> Alexey Perevalov (6):
>>> migration: introduce postcopy-blocktime capability
>>> migration: add postcopy blocktime ctx into MigrationIncomingState
>>> migration: calculate vCPU blocktime on dst side
>>> migration: postcopy_blocktime documentation
>>> migration: add blocktime calculation into migration-test
>>> migration: add postcopy total blocktime into query-migrate
>>
>> I had unanswered questions about these patches in the v12 series, where
>> I'm not sure if the interface is still quite right.
>
> To be fair, I had alroady integrated the patches before I saw your questions.
>
>> We're still early
>> enough that we could adjust the interface after the fact depending on
>> how the questions are answered;
>
> I think this is the best approach, so far I can see two questions:
>
> - do we want to make it conditional? it requires some locking, but I
> haven't meassured it to see how slow/fast is it.
>
> - the other was documentation.
>
> I will like Alexey to answer. Depending of how slow it is, I can agree
> to make it non-optional.
So have you come to a consensus on whether you'd like me to apply
this pull request or not ?
thanks
-- PMM
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [Qemu-devel] [PULL 00/14] Migration pull request
2018-01-09 18:24 ` Peter Maydell
@ 2018-01-09 18:28 ` Juan Quintela
0 siblings, 0 replies; 22+ messages in thread
From: Juan Quintela @ 2018-01-09 18:28 UTC (permalink / raw)
To: Peter Maydell
Cc: Eric Blake, Laurent Vivier, QEMU Developers, Markus Armbruster,
Peter Xu, Alexey, Dr. David Alan Gilbert
Peter Maydell <peter.maydell@linaro.org> wrote:
> On 5 January 2018 at 09:59, Juan Quintela <quintela@redhat.com> wrote:
>> Eric Blake <eblake@redhat.com> wrote:
>>> On 01/03/2018 03:38 AM, Juan Quintela wrote:
>>>> Hi
>>>>
>>>> This are the changes for migration that are already reviewed.
>>>>
>>>> Please, apply.
>>>>
>>>
>>>> Alexey Perevalov (6):
>>>> migration: introduce postcopy-blocktime capability
>>>> migration: add postcopy blocktime ctx into MigrationIncomingState
>>>> migration: calculate vCPU blocktime on dst side
>>>> migration: postcopy_blocktime documentation
>>>> migration: add blocktime calculation into migration-test
>>>> migration: add postcopy total blocktime into query-migrate
>>>
>>> I had unanswered questions about these patches in the v12 series, where
>>> I'm not sure if the interface is still quite right.
>>
>> To be fair, I had alroady integrated the patches before I saw your questions.
>>
>>> We're still early
>>> enough that we could adjust the interface after the fact depending on
>>> how the questions are answered;
>>
>> I think this is the best approach, so far I can see two questions:
>>
>> - do we want to make it conditional? it requires some locking, but I
>> haven't meassured it to see how slow/fast is it.
>>
>> - the other was documentation.
>>
>> I will like Alexey to answer. Depending of how slow it is, I can agree
>> to make it non-optional.
>
> So have you come to a consensus on whether you'd like me to apply
> this pull request or not ?
My understanding is that you should apply it. We will add a
documentation patch later.
Later, Juan.
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [Qemu-devel] [PULL 00/14] Migration pull request
2018-01-05 9:59 ` Juan Quintela
2018-01-09 18:24 ` Peter Maydell
@ 2018-01-10 4:58 ` Alexey Perevalov
1 sibling, 0 replies; 22+ messages in thread
From: Alexey Perevalov @ 2018-01-10 4:58 UTC (permalink / raw)
To: quintela, Eric Blake
Cc: qemu-devel, lvivier, dgilbert, peterx, Markus Armbruster
On 01/05/2018 12:59 PM, Juan Quintela wrote:
> Eric Blake <eblake@redhat.com> wrote:
>> On 01/03/2018 03:38 AM, Juan Quintela wrote:
>>> Hi
>>>
>>> This are the changes for migration that are already reviewed.
>>>
>>> Please, apply.
>>>
>>> Alexey Perevalov (6):
>>> migration: introduce postcopy-blocktime capability
>>> migration: add postcopy blocktime ctx into MigrationIncomingState
>>> migration: calculate vCPU blocktime on dst side
>>> migration: postcopy_blocktime documentation
>>> migration: add blocktime calculation into migration-test
>>> migration: add postcopy total blocktime into query-migrate
>> I had unanswered questions about these patches in the v12 series, where
>> I'm not sure if the interface is still quite right.
> To be fair, I had alroady integrated the patches before I saw your questions.
>
>> We're still early
>> enough that we could adjust the interface after the fact depending on
>> how the questions are answered;
> I think this is the best approach, so far I can see two questions:
>
> - do we want to make it conditional? it requires some locking, but I
> haven't meassured it to see how slow/fast is it.
>
> - the other was documentation.
>
> I will like Alexey to answer. Depending of how slow it is, I can agree
> to make it non-optional.
Ok, I'll give a logs with traces, maybe gprof result, today
or tomorrow.
>
>> but we're also early enough that it may
>> be smarter to get the interface right before including it in a pull
>> request. I'll leave it to Peter and Juan to sort out whether this means
>> an updated pull request is needed, or to take this as-is.
> Thanks, Juan.
>
>
>
--
Best regards,
Alexey Perevalov
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [Qemu-devel] [PULL 00/14] Migration pull request
2018-01-03 9:38 [Qemu-devel] [PULL 00/14] Migration pull request Juan Quintela
` (14 preceding siblings ...)
2018-01-05 0:30 ` [Qemu-devel] [PULL 00/14] Migration pull request Eric Blake
@ 2018-01-11 11:51 ` Peter Maydell
15 siblings, 0 replies; 22+ messages in thread
From: Peter Maydell @ 2018-01-11 11:51 UTC (permalink / raw)
To: Juan Quintela
Cc: QEMU Developers, Laurent Vivier, Dr. David Alan Gilbert, Peter Xu
On 3 January 2018 at 09:38, Juan Quintela <quintela@redhat.com> wrote:
> Hi
>
> This are the changes for migration that are already reviewed.
>
> Please, apply.
>
> Later, Juan.
>
>
> The following changes since commit 281f327487c9c9b1599f93c589a408bbf4a651b8:
>
> Merge remote-tracking branch 'remotes/vivier/tags/m68k-for-2.12-pull-request' into staging (2017-12-22 00:11:36 +0000)
>
> are available in the Git repository at:
>
> git://github.com/juanquintela/qemu.git tags/migration/20180103
>
> for you to fetch changes up to 8a18afdcd8d2d6ab31f9de89d2f20fdadb89beb8:
>
> migration: finalize current_migration object (2018-01-03 09:28:56 +0100)
>
> ----------------------------------------------------------------
> migration/next for 20180103
>
This fails to build on 32-bit systems:
/home/peter.maydell/qemu/migration/postcopy-ram.c: In function
'mark_postcopy_blocktime_begin':
/home/peter.maydell/qemu/migration/postcopy-ram.c:658:54: error: cast
to pointer from integer of different size
[-Werror=int-to-pointer-cast]
already_received = ramblock_recv_bitmap_test(rb, (void *)addr);
^
Keeping pointers in uint64_t and casting all over the place
looks like the wrong thing -- using the uintptr_t type will
likely make things cleaner.
This also looks suspicious:
atomic_xchg__nocheck(&dc->last_begin, now_ms);
atomic_xchg__nocheck(&dc->page_fault_vcpu_time[cpu], now_ms);
atomic_xchg__nocheck(&dc->vcpu_addr[cpu], addr);
because atomic operations on types larger than the host pointer
size are not portable to all architectures. This should probably
use the atomic_cmpxchg(), not __nocheck, because the latter
bypasses the build time assert for this problem and turns a
"fails on any 32-bit host" into "fails obscurely on some
architectures only".
thanks
-- PMM
^ permalink raw reply [flat|nested] 22+ messages in thread