mirror of
https://github.com/qemu/qemu.git
synced 2024-11-25 20:03:37 +08:00
kvm: Support for querying fd-based stats
Add support for querying fd-based KVM stats - as introduced by Linux kernel
commit:
cb082bfab59a ("KVM: stats: Add fd-based API to read binary stats data")
This allows the user to analyze the behavior of the VM without access
to debugfs.
Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Mark Kanda
Paolo Bonzini
parent
b9f88dc071
commit
cc01a3f4ca
@ -47,6 +47,7 @@
|
||||
#include "kvm-cpus.h"
|
||||
|
||||
#include "hw/boards.h"
|
||||
#include "monitor/stats.h"
|
||||
|
||||
/* This check must be after config-host.h is included */
|
||||
#ifdef CONFIG_EVENTFD
|
||||
@ -2310,6 +2311,9 @@ bool kvm_dirty_ring_enabled(void)
|
||||
return kvm_state->kvm_dirty_ring_size ? true : false;
|
||||
}
|
||||
|
||||
static void query_stats_cb(StatsResultList **result, StatsTarget target, Error **errp);
|
||||
static void query_stats_schemas_cb(StatsSchemaList **result, Error **errp);
|
||||
|
||||
static int kvm_init(MachineState *ms)
|
||||
{
|
||||
MachineClass *mc = MACHINE_GET_CLASS(ms);
|
||||
@ -2638,6 +2642,10 @@ static int kvm_init(MachineState *ms)
|
||||
}
|
||||
}
|
||||
|
||||
if (kvm_check_extension(kvm_state, KVM_CAP_BINARY_STATS_FD)) {
|
||||
add_stats_callbacks(query_stats_cb, query_stats_schemas_cb);
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
err:
|
||||
@ -3697,3 +3705,387 @@ static void kvm_type_init(void)
|
||||
}
|
||||
|
||||
type_init(kvm_type_init);
|
||||
|
||||
typedef struct StatsArgs {
|
||||
union StatsResultsType {
|
||||
StatsResultList **stats;
|
||||
StatsSchemaList **schema;
|
||||
} result;
|
||||
Error **errp;
|
||||
} StatsArgs;
|
||||
|
||||
static StatsList *add_kvmstat_entry(struct kvm_stats_desc *pdesc,
|
||||
uint64_t *stats_data,
|
||||
StatsList *stats_list,
|
||||
Error **errp)
|
||||
{
|
||||
|
||||
Stats *stats;
|
||||
uint64List *val_list = NULL;
|
||||
|
||||
/* Only add stats that we understand. */
|
||||
switch (pdesc->flags & KVM_STATS_TYPE_MASK) {
|
||||
case KVM_STATS_TYPE_CUMULATIVE:
|
||||
case KVM_STATS_TYPE_INSTANT:
|
||||
case KVM_STATS_TYPE_PEAK:
|
||||
case KVM_STATS_TYPE_LINEAR_HIST:
|
||||
case KVM_STATS_TYPE_LOG_HIST:
|
||||
break;
|
||||
default:
|
||||
return stats_list;
|
||||
}
|
||||
|
||||
switch (pdesc->flags & KVM_STATS_UNIT_MASK) {
|
||||
case KVM_STATS_UNIT_NONE:
|
||||
case KVM_STATS_UNIT_BYTES:
|
||||
case KVM_STATS_UNIT_CYCLES:
|
||||
case KVM_STATS_UNIT_SECONDS:
|
||||
break;
|
||||
default:
|
||||
return stats_list;
|
||||
}
|
||||
|
||||
switch (pdesc->flags & KVM_STATS_BASE_MASK) {
|
||||
case KVM_STATS_BASE_POW10:
|
||||
case KVM_STATS_BASE_POW2:
|
||||
break;
|
||||
default:
|
||||
return stats_list;
|
||||
}
|
||||
|
||||
/* Alloc and populate data list */
|
||||
stats = g_new0(Stats, 1);
|
||||
stats->name = g_strdup(pdesc->name);
|
||||
stats->value = g_new0(StatsValue, 1);;
|
||||
|
||||
if (pdesc->size == 1) {
|
||||
stats->value->u.scalar = *stats_data;
|
||||
stats->value->type = QTYPE_QNUM;
|
||||
} else {
|
||||
int i;
|
||||
for (i = 0; i < pdesc->size; i++) {
|
||||
QAPI_LIST_PREPEND(val_list, stats_data[i]);
|
||||
}
|
||||
stats->value->u.list = val_list;
|
||||
stats->value->type = QTYPE_QLIST;
|
||||
}
|
||||
|
||||
QAPI_LIST_PREPEND(stats_list, stats);
|
||||
return stats_list;
|
||||
}
|
||||
|
||||
static StatsSchemaValueList *add_kvmschema_entry(struct kvm_stats_desc *pdesc,
|
||||
StatsSchemaValueList *list,
|
||||
Error **errp)
|
||||
{
|
||||
StatsSchemaValueList *schema_entry = g_new0(StatsSchemaValueList, 1);
|
||||
schema_entry->value = g_new0(StatsSchemaValue, 1);
|
||||
|
||||
switch (pdesc->flags & KVM_STATS_TYPE_MASK) {
|
||||
case KVM_STATS_TYPE_CUMULATIVE:
|
||||
schema_entry->value->type = STATS_TYPE_CUMULATIVE;
|
||||
break;
|
||||
case KVM_STATS_TYPE_INSTANT:
|
||||
schema_entry->value->type = STATS_TYPE_INSTANT;
|
||||
break;
|
||||
case KVM_STATS_TYPE_PEAK:
|
||||
schema_entry->value->type = STATS_TYPE_PEAK;
|
||||
break;
|
||||
case KVM_STATS_TYPE_LINEAR_HIST:
|
||||
schema_entry->value->type = STATS_TYPE_LINEAR_HISTOGRAM;
|
||||
schema_entry->value->bucket_size = pdesc->bucket_size;
|
||||
schema_entry->value->has_bucket_size = true;
|
||||
break;
|
||||
case KVM_STATS_TYPE_LOG_HIST:
|
||||
schema_entry->value->type = STATS_TYPE_LOG2_HISTOGRAM;
|
||||
break;
|
||||
default:
|
||||
goto exit;
|
||||
}
|
||||
|
||||
switch (pdesc->flags & KVM_STATS_UNIT_MASK) {
|
||||
case KVM_STATS_UNIT_NONE:
|
||||
break;
|
||||
case KVM_STATS_UNIT_BYTES:
|
||||
schema_entry->value->has_unit = true;
|
||||
schema_entry->value->unit = STATS_UNIT_BYTES;
|
||||
break;
|
||||
case KVM_STATS_UNIT_CYCLES:
|
||||
schema_entry->value->has_unit = true;
|
||||
schema_entry->value->unit = STATS_UNIT_CYCLES;
|
||||
break;
|
||||
case KVM_STATS_UNIT_SECONDS:
|
||||
schema_entry->value->has_unit = true;
|
||||
schema_entry->value->unit = STATS_UNIT_SECONDS;
|
||||
break;
|
||||
default:
|
||||
goto exit;
|
||||
}
|
||||
|
||||
schema_entry->value->exponent = pdesc->exponent;
|
||||
if (pdesc->exponent) {
|
||||
switch (pdesc->flags & KVM_STATS_BASE_MASK) {
|
||||
case KVM_STATS_BASE_POW10:
|
||||
schema_entry->value->has_base = true;
|
||||
schema_entry->value->base = 10;
|
||||
break;
|
||||
case KVM_STATS_BASE_POW2:
|
||||
schema_entry->value->has_base = true;
|
||||
schema_entry->value->base = 2;
|
||||
break;
|
||||
default:
|
||||
goto exit;
|
||||
}
|
||||
}
|
||||
|
||||
schema_entry->value->name = g_strdup(pdesc->name);
|
||||
schema_entry->next = list;
|
||||
return schema_entry;
|
||||
exit:
|
||||
g_free(schema_entry->value);
|
||||
g_free(schema_entry);
|
||||
return list;
|
||||
}
|
||||
|
||||
/* Cached stats descriptors */
|
||||
typedef struct StatsDescriptors {
|
||||
const char *ident; /* cache key, currently the StatsTarget */
|
||||
struct kvm_stats_desc *kvm_stats_desc;
|
||||
struct kvm_stats_header *kvm_stats_header;
|
||||
QTAILQ_ENTRY(StatsDescriptors) next;
|
||||
} StatsDescriptors;
|
||||
|
||||
static QTAILQ_HEAD(, StatsDescriptors) stats_descriptors =
|
||||
QTAILQ_HEAD_INITIALIZER(stats_descriptors);
|
||||
|
||||
/*
|
||||
* Return the descriptors for 'target', that either have already been read
|
||||
* or are retrieved from 'stats_fd'.
|
||||
*/
|
||||
static StatsDescriptors *find_stats_descriptors(StatsTarget target, int stats_fd,
|
||||
Error **errp)
|
||||
{
|
||||
StatsDescriptors *descriptors;
|
||||
const char *ident;
|
||||
struct kvm_stats_desc *kvm_stats_desc;
|
||||
struct kvm_stats_header *kvm_stats_header;
|
||||
size_t size_desc;
|
||||
ssize_t ret;
|
||||
|
||||
ident = StatsTarget_str(target);
|
||||
QTAILQ_FOREACH(descriptors, &stats_descriptors, next) {
|
||||
if (g_str_equal(descriptors->ident, ident)) {
|
||||
return descriptors;
|
||||
}
|
||||
}
|
||||
|
||||
descriptors = g_new0(StatsDescriptors, 1);
|
||||
|
||||
/* Read stats header */
|
||||
kvm_stats_header = g_malloc(sizeof(*kvm_stats_header));
|
||||
ret = read(stats_fd, kvm_stats_header, sizeof(*kvm_stats_header));
|
||||
if (ret != sizeof(*kvm_stats_header)) {
|
||||
error_setg(errp, "KVM stats: failed to read stats header: "
|
||||
"expected %zu actual %zu",
|
||||
sizeof(*kvm_stats_header), ret);
|
||||
return NULL;
|
||||
}
|
||||
size_desc = sizeof(*kvm_stats_desc) + kvm_stats_header->name_size;
|
||||
|
||||
/* Read stats descriptors */
|
||||
kvm_stats_desc = g_malloc0_n(kvm_stats_header->num_desc, size_desc);
|
||||
ret = pread(stats_fd, kvm_stats_desc,
|
||||
size_desc * kvm_stats_header->num_desc,
|
||||
kvm_stats_header->desc_offset);
|
||||
|
||||
if (ret != size_desc * kvm_stats_header->num_desc) {
|
||||
error_setg(errp, "KVM stats: failed to read stats descriptors: "
|
||||
"expected %zu actual %zu",
|
||||
size_desc * kvm_stats_header->num_desc, ret);
|
||||
g_free(descriptors);
|
||||
g_free(kvm_stats_desc);
|
||||
return NULL;
|
||||
}
|
||||
descriptors->kvm_stats_header = kvm_stats_header;
|
||||
descriptors->kvm_stats_desc = kvm_stats_desc;
|
||||
descriptors->ident = ident;
|
||||
QTAILQ_INSERT_TAIL(&stats_descriptors, descriptors, next);
|
||||
return descriptors;
|
||||
}
|
||||
|
||||
static void query_stats(StatsResultList **result, StatsTarget target,
|
||||
int stats_fd, Error **errp)
|
||||
{
|
||||
struct kvm_stats_desc *kvm_stats_desc;
|
||||
struct kvm_stats_header *kvm_stats_header;
|
||||
StatsDescriptors *descriptors;
|
||||
g_autofree uint64_t *stats_data = NULL;
|
||||
struct kvm_stats_desc *pdesc;
|
||||
StatsList *stats_list = NULL;
|
||||
size_t size_desc, size_data = 0;
|
||||
ssize_t ret;
|
||||
int i;
|
||||
|
||||
descriptors = find_stats_descriptors(target, stats_fd, errp);
|
||||
if (!descriptors) {
|
||||
return;
|
||||
}
|
||||
|
||||
kvm_stats_header = descriptors->kvm_stats_header;
|
||||
kvm_stats_desc = descriptors->kvm_stats_desc;
|
||||
size_desc = sizeof(*kvm_stats_desc) + kvm_stats_header->name_size;
|
||||
|
||||
/* Tally the total data size; read schema data */
|
||||
for (i = 0; i < kvm_stats_header->num_desc; ++i) {
|
||||
pdesc = (void *)kvm_stats_desc + i * size_desc;
|
||||
size_data += pdesc->size * sizeof(*stats_data);
|
||||
}
|
||||
|
||||
stats_data = g_malloc0(size_data);
|
||||
ret = pread(stats_fd, stats_data, size_data, kvm_stats_header->data_offset);
|
||||
|
||||
if (ret != size_data) {
|
||||
error_setg(errp, "KVM stats: failed to read data: "
|
||||
"expected %zu actual %zu", size_data, ret);
|
||||
return;
|
||||
}
|
||||
|
||||
for (i = 0; i < kvm_stats_header->num_desc; ++i) {
|
||||
uint64_t *stats;
|
||||
pdesc = (void *)kvm_stats_desc + i * size_desc;
|
||||
|
||||
/* Add entry to the list */
|
||||
stats = (void *)stats_data + pdesc->offset;
|
||||
stats_list = add_kvmstat_entry(pdesc, stats, stats_list, errp);
|
||||
}
|
||||
|
||||
if (!stats_list) {
|
||||
return;
|
||||
}
|
||||
|
||||
switch (target) {
|
||||
case STATS_TARGET_VM:
|
||||
add_stats_entry(result, STATS_PROVIDER_KVM, NULL, stats_list);
|
||||
break;
|
||||
case STATS_TARGET_VCPU:
|
||||
add_stats_entry(result, STATS_PROVIDER_KVM,
|
||||
current_cpu->parent_obj.canonical_path,
|
||||
stats_list);
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
static void query_stats_schema(StatsSchemaList **result, StatsTarget target,
|
||||
int stats_fd, Error **errp)
|
||||
{
|
||||
struct kvm_stats_desc *kvm_stats_desc;
|
||||
struct kvm_stats_header *kvm_stats_header;
|
||||
StatsDescriptors *descriptors;
|
||||
struct kvm_stats_desc *pdesc;
|
||||
StatsSchemaValueList *stats_list = NULL;
|
||||
size_t size_desc;
|
||||
int i;
|
||||
|
||||
descriptors = find_stats_descriptors(target, stats_fd, errp);
|
||||
if (!descriptors) {
|
||||
return;
|
||||
}
|
||||
|
||||
kvm_stats_header = descriptors->kvm_stats_header;
|
||||
kvm_stats_desc = descriptors->kvm_stats_desc;
|
||||
size_desc = sizeof(*kvm_stats_desc) + kvm_stats_header->name_size;
|
||||
|
||||
/* Tally the total data size; read schema data */
|
||||
for (i = 0; i < kvm_stats_header->num_desc; ++i) {
|
||||
pdesc = (void *)kvm_stats_desc + i * size_desc;
|
||||
stats_list = add_kvmschema_entry(pdesc, stats_list, errp);
|
||||
}
|
||||
|
||||
add_stats_schema(result, STATS_PROVIDER_KVM, target, stats_list);
|
||||
}
|
||||
|
||||
static void query_stats_vcpu(CPUState *cpu, run_on_cpu_data data)
|
||||
{
|
||||
StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
|
||||
int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
|
||||
Error *local_err = NULL;
|
||||
|
||||
if (stats_fd == -1) {
|
||||
error_setg_errno(&local_err, errno, "KVM stats: ioctl failed");
|
||||
error_propagate(kvm_stats_args->errp, local_err);
|
||||
return;
|
||||
}
|
||||
query_stats(kvm_stats_args->result.stats, STATS_TARGET_VCPU, stats_fd,
|
||||
kvm_stats_args->errp);
|
||||
close(stats_fd);
|
||||
}
|
||||
|
||||
static void query_stats_schema_vcpu(CPUState *cpu, run_on_cpu_data data)
|
||||
{
|
||||
StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
|
||||
int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
|
||||
Error *local_err = NULL;
|
||||
|
||||
if (stats_fd == -1) {
|
||||
error_setg_errno(&local_err, errno, "KVM stats: ioctl failed");
|
||||
error_propagate(kvm_stats_args->errp, local_err);
|
||||
return;
|
||||
}
|
||||
query_stats_schema(kvm_stats_args->result.schema, STATS_TARGET_VCPU, stats_fd,
|
||||
kvm_stats_args->errp);
|
||||
close(stats_fd);
|
||||
}
|
||||
|
||||
static void query_stats_cb(StatsResultList **result, StatsTarget target, Error **errp)
|
||||
{
|
||||
KVMState *s = kvm_state;
|
||||
CPUState *cpu;
|
||||
int stats_fd;
|
||||
|
||||
switch (target) {
|
||||
case STATS_TARGET_VM:
|
||||
{
|
||||
stats_fd = kvm_vm_ioctl(s, KVM_GET_STATS_FD, NULL);
|
||||
if (stats_fd == -1) {
|
||||
error_setg_errno(errp, errno, "KVM stats: ioctl failed");
|
||||
return;
|
||||
}
|
||||
query_stats(result, target, stats_fd, errp);
|
||||
close(stats_fd);
|
||||
break;
|
||||
}
|
||||
case STATS_TARGET_VCPU:
|
||||
{
|
||||
StatsArgs stats_args;
|
||||
stats_args.result.stats = result;
|
||||
stats_args.errp = errp;
|
||||
CPU_FOREACH(cpu) {
|
||||
run_on_cpu(cpu, query_stats_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
|
||||
}
|
||||
break;
|
||||
}
|
||||
default:
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
void query_stats_schemas_cb(StatsSchemaList **result, Error **errp)
|
||||
{
|
||||
StatsArgs stats_args;
|
||||
KVMState *s = kvm_state;
|
||||
int stats_fd;
|
||||
|
||||
stats_fd = kvm_vm_ioctl(s, KVM_GET_STATS_FD, NULL);
|
||||
if (stats_fd == -1) {
|
||||
error_setg_errno(errp, errno, "KVM stats: ioctl failed");
|
||||
return;
|
||||
}
|
||||
query_stats_schema(result, STATS_TARGET_VM, stats_fd, errp);
|
||||
close(stats_fd);
|
||||
|
||||
stats_args.result.schema = result;
|
||||
stats_args.errp = errp;
|
||||
run_on_cpu(first_cpu, query_stats_schema_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
|
||||
}
|
||||
|
||||
@ -52,7 +52,7 @@
|
||||
# Since: 7.1
|
||||
##
|
||||
{ 'enum': 'StatsProvider',
|
||||
'data': [ ] }
|
||||
'data': [ 'kvm' ] }
|
||||
|
||||
##
|
||||
# @StatsTarget:
|
||||
|
||||
Loading…
Reference in New Issue
Block a user