haraldwolff/qemu-patch-raspberry4
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

savevm: split the process of different stages for loadvm/savevm

Browse source 
There are several stages during loadvm/savevm process. In different stage,
migration incoming processes different types of sections.
We want to control these stages more accuracy, it will benefit COLO
performance, we don't have to save type of QEMU_VM_SECTION_START
sections everytime while do checkpoint, besides, we want to separate
the process of saving/loading memory and devices state.

So we add three new helper functions: qemu_load_device_state() and
qemu_savevm_live_state() to achieve different process during migration.

Besides, we make qemu_loadvm_state_main() and qemu_save_device_state()
public, and simplify the codes of qemu_save_device_state() by calling the
wrapper qemu_savevm_state_header().

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This commit is contained in:
Zhang Chen 2018-09-03 12:38:54 +08:00 committed by Jason Wang
parent f56c0065b8
commit 3f6df99d9d
3 changed files with 65 additions and 16 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

41
migration/colo.c
View file

@ -30,6 +30,7 @@
#include "block/block.h"
#include "qapi/qapi-events-migration.h"
#include "qapi/qmp/qerror.h"
#include "sysemu/cpus.h"
static bool vmstate_loading;
static Notifier packets_compare_notifier;
@ -401,23 +402,34 @@ static int colo_do_checkpoint_transaction(MigrationState *s,
/* Disable block migration */
migrate_set_block_enabled(false, &local_err);
qemu_savevm_state_header(fb);
qemu_savevm_state_setup(fb);
qemu_mutex_lock_iothread();
replication_do_checkpoint_all(&local_err);
if (local_err) {
qemu_mutex_unlock_iothread();
goto out;
}
qemu_savevm_state_complete_precopy(fb, false, false);
qemu_mutex_unlock_iothread();
qemu_fflush(fb);
colo_send_message(s->to_dst_file, COLO_MESSAGE_VMSTATE_SEND, &local_err);
if (local_err) {
qemu_mutex_unlock_iothread();
goto out;
}
/* Note: device state is saved into buffer */
ret = qemu_save_device_state(fb);
qemu_mutex_unlock_iothread();
if (ret < 0) {
goto out;
}
/*
* Only save VM's live state, which not including device state.
* TODO: We may need a timeout mechanism to prevent COLO process
* to be blocked here.
*/
qemu_savevm_live_state(s->to_dst_file);
qemu_fflush(fb);
/*
* We need the size of the VMstate data in Secondary side,
* With which we can decide how much data should be read.
@ -635,6 +647,7 @@ void *colo_process_incoming_thread(void *opaque)
uint64_t total_size;
uint64_t value;
Error *local_err = NULL;
int ret;
rcu_register_thread();
qemu_sem_init(&mis->colo_incoming_sem, 0);
@ -708,6 +721,16 @@ void *colo_process_incoming_thread(void *opaque)
goto out;
}
qemu_mutex_lock_iothread();
cpu_synchronize_all_pre_loadvm();
ret = qemu_loadvm_state_main(mis->from_src_file, mis);
qemu_mutex_unlock_iothread();
if (ret < 0) {
error_report("Load VM's live state (ram) error");
goto out;
}
value = colo_receive_message_value(mis->from_src_file,
COLO_MESSAGE_VMSTATE_SIZE, &local_err);
if (local_err) {
@ -739,10 +762,10 @@ void *colo_process_incoming_thread(void *opaque)
}
qemu_mutex_lock_iothread();
qemu_system_reset(SHUTDOWN_CAUSE_NONE);
vmstate_loading = true;
if (qemu_loadvm_state(fb) < 0) {
error_report("COLO: loadvm failed");
ret = qemu_load_device_state(fb);
if (ret < 0) {
error_report("COLO: load device state failed");
qemu_mutex_unlock_iothread();
goto out;
}

36
migration/savevm.c
View file

@ -1378,13 +1378,21 @@ done:
return ret;
}
static int qemu_save_device_state(QEMUFile *f)
void qemu_savevm_live_state(QEMUFile *f)
{
/* save QEMU_VM_SECTION_END section */
qemu_savevm_state_complete_precopy(f, true, false);
qemu_put_byte(f, QEMU_VM_EOF);
}
int qemu_save_device_state(QEMUFile *f)
{
SaveStateEntry *se;
qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
qemu_put_be32(f, QEMU_VM_FILE_VERSION);
if (!migration_in_colo_state()) {
qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
qemu_put_be32(f, QEMU_VM_FILE_VERSION);
}
cpu_synchronize_all_states();
QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
@ -1440,8 +1448,6 @@ enum LoadVMExitCodes {
LOADVM_QUIT = 1,
};
static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis);
/* ------ incoming postcopy messages ------ */
/* 'advise' arrives before any transfers just to tell us that a postcopy
* *might* happen - it might be skipped if precopy transferred everything
@ -2247,7 +2253,7 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis)
return true;
}
static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis)
int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis)
{
uint8_t section_type;
int ret = 0;
@ -2418,6 +2424,22 @@ int qemu_loadvm_state(QEMUFile *f)
return ret;
}
int qemu_load_device_state(QEMUFile *f)
{
MigrationIncomingState *mis = migration_incoming_get_current();
int ret;
/* Load QEMU_VM_SECTION_FULL section */
ret = qemu_loadvm_state_main(f, mis);
if (ret < 0) {
error_report("Failed to load device state: %d", ret);
return ret;
}
cpu_synchronize_all_post_init();
return 0;
}
int save_snapshot(const char *name, Error **errp)
{
BlockDriverState *bs, *bs1;

4
migration/savevm.h
View file

@ -56,8 +56,12 @@ void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name,
uint64_t *start_list,
uint64_t *length_list);
void qemu_savevm_send_colo_enable(QEMUFile *f);
void qemu_savevm_live_state(QEMUFile *f);
int qemu_save_device_state(QEMUFile *f);
int qemu_loadvm_state(QEMUFile *f);
void qemu_loadvm_state_cleanup(void);
int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis);
int qemu_load_device_state(QEMUFile *f);
#endif