migration/dirtyrate: implement dirty-bitmap dirtyrate calculation

introduce dirty-bitmap mode as the third method of calc-dirty-rate.
implement dirty-bitmap dirtyrate calculation, which can be used
to measuring dirtyrate in the absence of dirty-ring.

introduce "dirty_bitmap:-b" option in hmp calc_dirty_rate to
indicate dirty bitmap method should be used for calculation.

Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
Hyman Huang(黄勇) 2021-07-20 23:19:17 +08:00 committed by Juan Quintela
parent 4998a37e4b
commit 826b8bc80c
3 changed files with 112 additions and 15 deletions

View File

@ -1737,9 +1737,10 @@ ERST
{
.name = "calc_dirty_rate",
.args_type = "dirty_ring:-r,second:l,sample_pages_per_GB:l?",
.params = "[-r] second [sample_pages_per_GB]",
.help = "start a round of guest dirty rate measurement (using -d to"
"\n\t\t\t specify dirty ring as the method of calculation)",
.args_type = "dirty_ring:-r,dirty_bitmap:-b,second:l,sample_pages_per_GB:l?",
.params = "[-r] [-b] second [sample_pages_per_GB]",
.help = "start a round of guest dirty rate measurement (using -r to"
"\n\t\t\t specify dirty ring as the method of calculation and"
"\n\t\t\t -b to specify dirty bitmap as method of calculation)",
.cmd = hmp_calc_dirty_rate,
},

View File

@ -15,6 +15,7 @@
#include "qapi/error.h"
#include "cpu.h"
#include "exec/ramblock.h"
#include "exec/ram_addr.h"
#include "qemu/rcu_queue.h"
#include "qemu/main-loop.h"
#include "qapi/qapi-commands-migration.h"
@ -118,6 +119,10 @@ static struct DirtyRateInfo *query_dirty_rate_info(void)
}
info->vcpu_dirty_rate = head;
}
if (dirtyrate_mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) {
info->sample_pages = 0;
}
}
trace_query_dirty_rate_info(DirtyRateStatus_str(CalculatingState));
@ -429,6 +434,79 @@ static int64_t do_calculate_dirtyrate_vcpu(DirtyPageRecord dirty_pages)
return memory_size_MB / time_s;
}
static inline void record_dirtypages_bitmap(DirtyPageRecord *dirty_pages,
bool start)
{
if (start) {
dirty_pages->start_pages = total_dirty_pages;
} else {
dirty_pages->end_pages = total_dirty_pages;
}
}
static void do_calculate_dirtyrate_bitmap(DirtyPageRecord dirty_pages)
{
DirtyStat.dirty_rate = do_calculate_dirtyrate_vcpu(dirty_pages);
}
static inline void dirtyrate_manual_reset_protect(void)
{
RAMBlock *block = NULL;
WITH_RCU_READ_LOCK_GUARD() {
RAMBLOCK_FOREACH_MIGRATABLE(block) {
memory_region_clear_dirty_bitmap(block->mr, 0,
block->used_length);
}
}
}
static void calculate_dirtyrate_dirty_bitmap(struct DirtyRateConfig config)
{
int64_t msec = 0;
int64_t start_time;
DirtyPageRecord dirty_pages;
qemu_mutex_lock_iothread();
memory_global_dirty_log_start(GLOBAL_DIRTY_DIRTY_RATE);
/*
* 1'round of log sync may return all 1 bits with
* KVM_DIRTY_LOG_INITIALLY_SET enable
* skip it unconditionally and start dirty tracking
* from 2'round of log sync
*/
memory_global_dirty_log_sync();
/*
* reset page protect manually and unconditionally.
* this make sure kvm dirty log be cleared if
* KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE cap is enabled.
*/
dirtyrate_manual_reset_protect();
qemu_mutex_unlock_iothread();
record_dirtypages_bitmap(&dirty_pages, true);
start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
DirtyStat.start_time = start_time / 1000;
msec = config.sample_period_seconds * 1000;
msec = set_sample_page_period(msec, start_time);
DirtyStat.calc_time = msec / 1000;
/*
* dirtyrate_global_dirty_log_stop do two things.
* 1. fetch dirty bitmap from kvm
* 2. stop dirty tracking
*/
dirtyrate_global_dirty_log_stop();
record_dirtypages_bitmap(&dirty_pages, false);
do_calculate_dirtyrate_bitmap(dirty_pages);
}
static void calculate_dirtyrate_dirty_ring(struct DirtyRateConfig config)
{
CPUState *cpu;
@ -514,7 +592,9 @@ out:
static void calculate_dirtyrate(struct DirtyRateConfig config)
{
if (config.mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) {
if (config.mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) {
calculate_dirtyrate_dirty_bitmap(config);
} else if (config.mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) {
calculate_dirtyrate_dirty_ring(config);
} else {
calculate_dirtyrate_sample_vm(config);
@ -597,12 +677,15 @@ void qmp_calc_dirty_rate(int64_t calc_time,
/*
* dirty ring mode only works when kvm dirty ring is enabled.
* on the contrary, dirty bitmap mode is not.
*/
if ((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) &&
!kvm_dirty_ring_enabled()) {
error_setg(errp, "dirty ring is disabled, use sample-pages method "
"or remeasure later.");
return;
if (((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) &&
!kvm_dirty_ring_enabled()) ||
((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) &&
kvm_dirty_ring_enabled())) {
error_setg(errp, "mode %s is not enabled, use other method instead.",
DirtyRateMeasureMode_str(mode));
return;
}
/*
@ -678,9 +761,8 @@ void hmp_calc_dirty_rate(Monitor *mon, const QDict *qdict)
int64_t sample_pages = qdict_get_try_int(qdict, "sample_pages_per_GB", -1);
bool has_sample_pages = (sample_pages != -1);
bool dirty_ring = qdict_get_try_bool(qdict, "dirty_ring", false);
DirtyRateMeasureMode mode =
(dirty_ring ? DIRTY_RATE_MEASURE_MODE_DIRTY_RING :
DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING);
bool dirty_bitmap = qdict_get_try_bool(qdict, "dirty_bitmap", false);
DirtyRateMeasureMode mode = DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING;
Error *err = NULL;
if (!sec) {
@ -688,6 +770,18 @@ void hmp_calc_dirty_rate(Monitor *mon, const QDict *qdict)
return;
}
if (dirty_ring && dirty_bitmap) {
monitor_printf(mon, "Either dirty ring or dirty bitmap "
"can be specified!\n");
return;
}
if (dirty_bitmap) {
mode = DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP;
} else if (dirty_ring) {
mode = DIRTY_RATE_MEASURE_MODE_DIRTY_RING;
}
qmp_calc_dirty_rate(sec, has_sample_pages, sample_pages, true,
mode, &err);
if (err) {

View File

@ -1770,13 +1770,15 @@
#
# @page-sampling: calculate dirtyrate by sampling pages.
#
# @dirty-ring: calculate dirtyrate by via dirty ring.
# @dirty-ring: calculate dirtyrate by dirty ring.
#
# @dirty-bitmap: calculate dirtyrate by dirty bitmap.
#
# Since: 6.1
#
##
{ 'enum': 'DirtyRateMeasureMode',
'data': ['page-sampling', 'dirty-ring'] }
'data': ['page-sampling', 'dirty-ring', 'dirty-bitmap'] }
##
# @DirtyRateInfo: