qemu-e2k/monitor/qmp-cmds.c
Mark Kanda b9f88dc071 qmp: Support for querying stats
Gathering statistics is important for development, for monitoring and
for performance measurement.  There are tools such as kvm_stat that do
this and they rely on the _user_ knowing the interesting data points
rather than the tool (which can treat them as opaque).

The commands introduced in this commit introduce QMP support for
querying stats; the goal is to take the capabilities of these tools
and making them available throughout the whole virtualization stack,
so that one can observe, monitor and measure virtual machines without
having shell access + root on the host that runs them.

query-stats returns a list of all stats per target type (only VM
and vCPU to start); future commits add extra options for specifying
stat names, vCPU qom paths, and providers.  All these are used by the
HMP command "info stats".  Because of the development usecases around
statistics, a good HMP interface is important.

query-stats-schemas returns a list of stats included in each target
type, with an option for specifying the provider.  The concepts in the
schema are based on the KVM binary stats' own introspection data, just
translated to QAPI.

There are two reasons to have a separate schema that is not tied to
the QAPI schema.  The first is the contents of the schemas: the new
introspection data provides different information than the QAPI data,
namely unit of measurement, how the numbers are gathered and change
(peak/instant/cumulative/histogram), and histogram bucket sizes.
There's really no reason to have this kind of metadata in the QAPI
introspection schema (except possibly for the unit of measure, but
there's a very weak justification).

Another reason is the dynamicity of the schema.  The QAPI introspection
data is very much static; and while QOM is somewhat more dynamic,
generally we consider that to be a bug rather than a feature these days.
On the other hand, the statistics that are exposed by QEMU might be
passed through from another source, such as KVM, and the disadvantages of
manually updating the QAPI schema for outweight the benefits from vetting
the statistics and filtering out anything that seems "too unstable".
Running old QEMU with new kernel is a supported usecase; if old QEMU
cannot expose statistics from a new kernel, or if a kernel developer
needs to change QEMU before gathering new info from the new kernel,
then that is a poor user interface.

The framework provides a method to register callbacks for these QMP
commands.  Most of the work in fact is done by the callbacks, and a
large majority of this patch is new QAPI structs and commands.

Examples (with KVM stats):

- Query all VM stats:

{ "execute": "query-stats", "arguments" : { "target": "vm" } }

{ "return": [
     { "provider": "kvm",
       "stats": [
          { "name": "max_mmu_page_hash_collisions", "value": 0 },
          { "name": "max_mmu_rmap_size", "value": 0 },
          { "name": "nx_lpage_splits", "value": 148 },
          ... ] },
     { "provider": "xyz",
       "stats": [ ... ] }
] }

- Query all vCPU stats:

{ "execute": "query-stats", "arguments" : { "target": "vcpu" } }

{ "return": [
     { "provider": "kvm",
       "qom_path": "/machine/unattached/device[0]"
       "stats": [
          { "name": "guest_mode", "value": 0 },
          { "name": "directed_yield_successful", "value": 0 },
          { "name": "directed_yield_attempted", "value": 106 },
          ... ] },
     { "provider": "kvm",
       "qom_path": "/machine/unattached/device[1]"
       "stats": [
          { "name": "guest_mode", "value": 0 },
          { "name": "directed_yield_successful", "value": 0 },
          { "name": "directed_yield_attempted", "value": 106 },
          ... ] },
] }

- Retrieve the schemas:

{ "execute": "query-stats-schemas" }

{ "return": [
    { "provider": "kvm",
      "target": "vcpu",
      "stats": [
         { "name": "guest_mode",
           "unit": "none",
           "base": 10,
           "exponent": 0,
           "type": "instant" },
        { "name": "directed_yield_successful",
           "unit": "none",
           "base": 10,
           "exponent": 0,
           "type": "cumulative" },
        ... ]
    },
    { "provider": "kvm",
      "target": "vm",
      "stats": [
        { "name": "max_mmu_page_hash_collisions",
           "unit": "none",
           "base": 10,
           "exponent": 0,
           "type": "peak" },
        ... ]
    },
    { "provider": "xyz",
      "target": "vm",
      "stats": [ ... ]
    }
] }

Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-14 16:50:29 +02:00

539 lines
14 KiB
C

/*
* QEMU Management Protocol commands
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "qemu/cutils.h"
#include "qemu/option.h"
#include "monitor/monitor.h"
#include "sysemu/sysemu.h"
#include "qemu/config-file.h"
#include "qemu/uuid.h"
#include "chardev/char.h"
#include "ui/qemu-spice.h"
#include "ui/console.h"
#include "ui/dbus-display.h"
#include "sysemu/kvm.h"
#include "sysemu/runstate.h"
#include "sysemu/runstate-action.h"
#include "sysemu/blockdev.h"
#include "sysemu/block-backend.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-acpi.h"
#include "qapi/qapi-commands-block.h"
#include "qapi/qapi-commands-control.h"
#include "qapi/qapi-commands-machine.h"
#include "qapi/qapi-commands-misc.h"
#include "qapi/qapi-commands-stats.h"
#include "qapi/qapi-commands-ui.h"
#include "qapi/type-helpers.h"
#include "qapi/qmp/qerror.h"
#include "exec/ramlist.h"
#include "hw/mem/memory-device.h"
#include "hw/acpi/acpi_dev_interface.h"
#include "hw/intc/intc.h"
#include "hw/rdma/rdma.h"
#include "monitor/stats.h"
NameInfo *qmp_query_name(Error **errp)
{
NameInfo *info = g_malloc0(sizeof(*info));
if (qemu_name) {
info->has_name = true;
info->name = g_strdup(qemu_name);
}
return info;
}
KvmInfo *qmp_query_kvm(Error **errp)
{
KvmInfo *info = g_malloc0(sizeof(*info));
info->enabled = kvm_enabled();
info->present = accel_find("kvm");
return info;
}
UuidInfo *qmp_query_uuid(Error **errp)
{
UuidInfo *info = g_malloc0(sizeof(*info));
info->UUID = qemu_uuid_unparse_strdup(&qemu_uuid);
return info;
}
void qmp_quit(Error **errp)
{
shutdown_action = SHUTDOWN_ACTION_POWEROFF;
qemu_system_shutdown_request(SHUTDOWN_CAUSE_HOST_QMP_QUIT);
}
void qmp_stop(Error **errp)
{
/* if there is a dump in background, we should wait until the dump
* finished */
if (qemu_system_dump_in_progress()) {
error_setg(errp, "There is a dump in process, please wait.");
return;
}
if (runstate_check(RUN_STATE_INMIGRATE)) {
autostart = 0;
} else {
vm_stop(RUN_STATE_PAUSED);
}
}
void qmp_system_reset(Error **errp)
{
qemu_system_reset_request(SHUTDOWN_CAUSE_HOST_QMP_SYSTEM_RESET);
}
void qmp_system_powerdown(Error **errp)
{
qemu_system_powerdown_request();
}
void qmp_cont(Error **errp)
{
BlockBackend *blk;
BlockJob *job;
Error *local_err = NULL;
/* if there is a dump in background, we should wait until the dump
* finished */
if (qemu_system_dump_in_progress()) {
error_setg(errp, "There is a dump in process, please wait.");
return;
}
if (runstate_needs_reset()) {
error_setg(errp, "Resetting the Virtual Machine is required");
return;
} else if (runstate_check(RUN_STATE_SUSPENDED)) {
return;
} else if (runstate_check(RUN_STATE_FINISH_MIGRATE)) {
error_setg(errp, "Migration is not finalized yet");
return;
}
for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
blk_iostatus_reset(blk);
}
for (job = block_job_next(NULL); job; job = block_job_next(job)) {
block_job_iostatus_reset(job);
}
/* Continuing after completed migration. Images have been inactivated to
* allow the destination to take control. Need to get control back now.
*
* If there are no inactive block nodes (e.g. because the VM was just
* paused rather than completing a migration), bdrv_inactivate_all() simply
* doesn't do anything. */
bdrv_activate_all(&local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (runstate_check(RUN_STATE_INMIGRATE)) {
autostart = 1;
} else {
vm_start();
}
}
void qmp_system_wakeup(Error **errp)
{
if (!qemu_wakeup_suspend_enabled()) {
error_setg(errp,
"wake-up from suspend is not supported by this guest");
return;
}
qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, errp);
}
void qmp_set_password(SetPasswordOptions *opts, Error **errp)
{
int rc;
if (opts->protocol == DISPLAY_PROTOCOL_SPICE) {
if (!qemu_using_spice(errp)) {
return;
}
rc = qemu_spice.set_passwd(opts->password,
opts->connected == SET_PASSWORD_ACTION_FAIL,
opts->connected == SET_PASSWORD_ACTION_DISCONNECT);
} else {
assert(opts->protocol == DISPLAY_PROTOCOL_VNC);
if (opts->connected != SET_PASSWORD_ACTION_KEEP) {
/* vnc supports "connected=keep" only */
error_setg(errp, QERR_INVALID_PARAMETER, "connected");
return;
}
/* Note that setting an empty password will not disable login through
* this interface. */
rc = vnc_display_password(opts->u.vnc.display, opts->password);
}
if (rc != 0) {
error_setg(errp, "Could not set password");
}
}
void qmp_expire_password(ExpirePasswordOptions *opts, Error **errp)
{
time_t when;
int rc;
const char *whenstr = opts->time;
if (strcmp(whenstr, "now") == 0) {
when = 0;
} else if (strcmp(whenstr, "never") == 0) {
when = TIME_MAX;
} else if (whenstr[0] == '+') {
when = time(NULL) + strtoull(whenstr+1, NULL, 10);
} else {
when = strtoull(whenstr, NULL, 10);
}
if (opts->protocol == DISPLAY_PROTOCOL_SPICE) {
if (!qemu_using_spice(errp)) {
return;
}
rc = qemu_spice.set_pw_expire(when);
} else {
assert(opts->protocol == DISPLAY_PROTOCOL_VNC);
rc = vnc_display_pw_expire(opts->u.vnc.display, when);
}
if (rc != 0) {
error_setg(errp, "Could not set password expire time");
}
}
#ifdef CONFIG_VNC
void qmp_change_vnc_password(const char *password, Error **errp)
{
if (vnc_display_password(NULL, password) < 0) {
error_setg(errp, "Could not set password");
}
}
#endif
void qmp_add_client(const char *protocol, const char *fdname,
bool has_skipauth, bool skipauth, bool has_tls, bool tls,
Error **errp)
{
Chardev *s;
int fd;
fd = monitor_get_fd(monitor_cur(), fdname, errp);
if (fd < 0) {
return;
}
if (strcmp(protocol, "spice") == 0) {
if (!qemu_using_spice(errp)) {
close(fd);
return;
}
skipauth = has_skipauth ? skipauth : false;
tls = has_tls ? tls : false;
if (qemu_spice.display_add_client(fd, skipauth, tls) < 0) {
error_setg(errp, "spice failed to add client");
close(fd);
}
return;
#ifdef CONFIG_VNC
} else if (strcmp(protocol, "vnc") == 0) {
skipauth = has_skipauth ? skipauth : false;
vnc_display_add_client(NULL, fd, skipauth);
return;
#endif
#ifdef CONFIG_DBUS_DISPLAY
} else if (strcmp(protocol, "@dbus-display") == 0) {
if (!qemu_using_dbus_display(errp)) {
close(fd);
return;
}
if (!qemu_dbus_display.add_client(fd, errp)) {
close(fd);
return;
}
return;
#endif
} else if ((s = qemu_chr_find(protocol)) != NULL) {
if (qemu_chr_add_client(s, fd) < 0) {
error_setg(errp, "failed to add client");
close(fd);
return;
}
return;
}
error_setg(errp, "protocol '%s' is invalid", protocol);
close(fd);
}
MemoryDeviceInfoList *qmp_query_memory_devices(Error **errp)
{
return qmp_memory_device_list();
}
ACPIOSTInfoList *qmp_query_acpi_ospm_status(Error **errp)
{
bool ambig;
ACPIOSTInfoList *head = NULL;
ACPIOSTInfoList **prev = &head;
Object *obj = object_resolve_path_type("", TYPE_ACPI_DEVICE_IF, &ambig);
if (obj) {
AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(obj);
AcpiDeviceIf *adev = ACPI_DEVICE_IF(obj);
adevc->ospm_status(adev, &prev);
} else {
error_setg(errp, "command is not supported, missing ACPI device");
}
return head;
}
MemoryInfo *qmp_query_memory_size_summary(Error **errp)
{
MemoryInfo *mem_info = g_new0(MemoryInfo, 1);
MachineState *ms = MACHINE(qdev_get_machine());
mem_info->base_memory = ms->ram_size;
mem_info->plugged_memory = get_plugged_memory_size();
mem_info->has_plugged_memory =
mem_info->plugged_memory != (uint64_t)-1;
return mem_info;
}
void qmp_display_reload(DisplayReloadOptions *arg, Error **errp)
{
switch (arg->type) {
case DISPLAY_RELOAD_TYPE_VNC:
#ifdef CONFIG_VNC
if (arg->u.vnc.has_tls_certs && arg->u.vnc.tls_certs) {
vnc_display_reload_certs(NULL, errp);
}
#else
error_setg(errp, "vnc is invalid, missing 'CONFIG_VNC'");
#endif
break;
default:
abort();
}
}
void qmp_display_update(DisplayUpdateOptions *arg, Error **errp)
{
switch (arg->type) {
case DISPLAY_UPDATE_TYPE_VNC:
#ifdef CONFIG_VNC
vnc_display_update(&arg->u.vnc, errp);
#else
error_setg(errp, "vnc is invalid, missing 'CONFIG_VNC'");
#endif
break;
default:
abort();
}
}
static int qmp_x_query_rdma_foreach(Object *obj, void *opaque)
{
RdmaProvider *rdma;
RdmaProviderClass *k;
GString *buf = opaque;
if (object_dynamic_cast(obj, INTERFACE_RDMA_PROVIDER)) {
rdma = RDMA_PROVIDER(obj);
k = RDMA_PROVIDER_GET_CLASS(obj);
if (k->format_statistics) {
k->format_statistics(rdma, buf);
} else {
g_string_append_printf(buf,
"RDMA statistics not available for %s.\n",
object_get_typename(obj));
}
}
return 0;
}
HumanReadableText *qmp_x_query_rdma(Error **errp)
{
g_autoptr(GString) buf = g_string_new("");
object_child_foreach_recursive(object_get_root(),
qmp_x_query_rdma_foreach, buf);
return human_readable_text_from_str(buf);
}
HumanReadableText *qmp_x_query_ramblock(Error **errp)
{
g_autoptr(GString) buf = ram_block_format();
return human_readable_text_from_str(buf);
}
static int qmp_x_query_irq_foreach(Object *obj, void *opaque)
{
InterruptStatsProvider *intc;
InterruptStatsProviderClass *k;
GString *buf = opaque;
if (object_dynamic_cast(obj, TYPE_INTERRUPT_STATS_PROVIDER)) {
intc = INTERRUPT_STATS_PROVIDER(obj);
k = INTERRUPT_STATS_PROVIDER_GET_CLASS(obj);
uint64_t *irq_counts;
unsigned int nb_irqs, i;
if (k->get_statistics &&
k->get_statistics(intc, &irq_counts, &nb_irqs)) {
if (nb_irqs > 0) {
g_string_append_printf(buf, "IRQ statistics for %s:\n",
object_get_typename(obj));
for (i = 0; i < nb_irqs; i++) {
if (irq_counts[i] > 0) {
g_string_append_printf(buf, "%2d: %" PRId64 "\n", i,
irq_counts[i]);
}
}
}
} else {
g_string_append_printf(buf,
"IRQ statistics not available for %s.\n",
object_get_typename(obj));
}
}
return 0;
}
HumanReadableText *qmp_x_query_irq(Error **errp)
{
g_autoptr(GString) buf = g_string_new("");
object_child_foreach_recursive(object_get_root(),
qmp_x_query_irq_foreach, buf);
return human_readable_text_from_str(buf);
}
typedef struct StatsCallbacks {
StatRetrieveFunc *stats_cb;
SchemaRetrieveFunc *schemas_cb;
QTAILQ_ENTRY(StatsCallbacks) next;
} StatsCallbacks;
static QTAILQ_HEAD(, StatsCallbacks) stats_callbacks =
QTAILQ_HEAD_INITIALIZER(stats_callbacks);
void add_stats_callbacks(StatRetrieveFunc *stats_fn,
SchemaRetrieveFunc *schemas_fn)
{
StatsCallbacks *entry = g_new(StatsCallbacks, 1);
entry->stats_cb = stats_fn;
entry->schemas_cb = schemas_fn;
QTAILQ_INSERT_TAIL(&stats_callbacks, entry, next);
}
static bool invoke_stats_cb(StatsCallbacks *entry,
StatsResultList **stats_results,
StatsFilter *filter,
Error **errp)
{
ERRP_GUARD();
entry->stats_cb(stats_results, filter->target, errp);
if (*errp) {
qapi_free_StatsResultList(*stats_results);
*stats_results = NULL;
return false;
}
return true;
}
StatsResultList *qmp_query_stats(StatsFilter *filter, Error **errp)
{
StatsResultList *stats_results = NULL;
StatsCallbacks *entry;
QTAILQ_FOREACH(entry, &stats_callbacks, next) {
if (!invoke_stats_cb(entry, &stats_results, filter, errp)) {
break;
}
}
return stats_results;
}
StatsSchemaList *qmp_query_stats_schemas(Error **errp)
{
StatsSchemaList *stats_results = NULL;
StatsCallbacks *entry;
ERRP_GUARD();
QTAILQ_FOREACH(entry, &stats_callbacks, next) {
entry->schemas_cb(&stats_results, errp);
if (*errp) {
qapi_free_StatsSchemaList(stats_results);
return NULL;
}
}
return stats_results;
}
void add_stats_entry(StatsResultList **stats_results, StatsProvider provider,
const char *qom_path, StatsList *stats_list)
{
StatsResult *entry = g_new0(StatsResult, 1);
entry->provider = provider;
if (qom_path) {
entry->has_qom_path = true;
entry->qom_path = g_strdup(qom_path);
}
entry->stats = stats_list;
QAPI_LIST_PREPEND(*stats_results, entry);
}
void add_stats_schema(StatsSchemaList **schema_results,
StatsProvider provider, StatsTarget target,
StatsSchemaValueList *stats_list)
{
StatsSchema *entry = g_new0(StatsSchema, 1);
entry->provider = provider;
entry->target = target;
entry->stats = stats_list;
QAPI_LIST_PREPEND(*schema_results, entry);
}