We separate the process of saving/loading ram and device state when do
checkpoint. We add new helpers for save/load ram/device. With this change,
we can directly transfer RAM from primary side to secondary side without
using channel-buffer as assistant, which also reduce the size of extra memory
was used during checkpoint.
Besides, we move the colo_flush_ram_cache to the proper position after the
above change.
Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
Signed-off-by: Li Zhijian <lizhij...@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
---
v16:
- Add Reviewd-by tag
v14:
- split two new patches from this patch
- Some minor fixes from Dave
v13:
- Re-use some existed helper functions to realize saving/loading
ram and device.
v11:
- Remove load configuration section in qemu_loadvm_state_begin()
---
migration/colo.c | 49 +++++++++++++++++++++++++++++++++++++++----------
migration/ram.c | 5 -----
migration/savevm.c | 4 ++++
3 files changed, 43 insertions(+), 15 deletions(-)
diff --git a/migration/colo.c b/migration/colo.c
index 50693bb..48cdf06 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -284,21 +284,37 @@ static int colo_do_checkpoint_transaction(MigrationState
*s,
goto out;
}
+ colo_send_message(s->to_dst_file, COLO_MESSAGE_VMSTATE_SEND, &local_err);
+ if (local_err) {
+ goto out;
+ }
+
/* Disable block migration */
s->params.blk = 0;
s->params.shared = 0;
- qemu_savevm_state_header(fb);
- qemu_savevm_state_begin(fb, &s->params);
+ qemu_savevm_state_begin(s->to_dst_file, &s->params);
+ ret = qemu_file_get_error(s->to_dst_file);
+ if (ret < 0) {
+ error_report("Save VM state begin error");
+ goto out;
+ }
+
qemu_mutex_lock_iothread();
- qemu_savevm_state_complete_precopy(fb, false);
+ /*
+ * 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);
+ /* Note: device state is saved into buffer */
+ ret = qemu_save_device_state(fb);
qemu_mutex_unlock_iothread();
-
- qemu_fflush(fb);
-
- colo_send_message(s->to_dst_file, COLO_MESSAGE_VMSTATE_SEND, &local_err);
- if (local_err) {
+ if (ret < 0) {
+ error_report("Save device state error");
goto out;
}
+ 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.
@@ -565,6 +581,17 @@ void *colo_process_incoming_thread(void *opaque)
goto out;
}
+ ret = qemu_loadvm_state_begin(mis->from_src_file);
+ if (ret < 0) {
+ error_report("Load vm state begin error, ret=%d", ret);
+ goto out;
+ }
+ ret = qemu_loadvm_state_main(mis->from_src_file, mis);
+ 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) {
@@ -599,8 +626,10 @@ void *colo_process_incoming_thread(void *opaque)
qemu_mutex_lock_iothread();
qemu_system_reset(VMRESET_SILENT);
vmstate_loading = true;
- if (qemu_loadvm_state(fb) < 0) {
- error_report("COLO: loadvm failed");
+ colo_flush_ram_cache();
+ ret = qemu_load_device_state(fb);
+ if (ret < 0) {
+ error_report("COLO: load device state failed");
qemu_mutex_unlock_iothread();
goto out;
}
diff --git a/migration/ram.c b/migration/ram.c
index 198dc53..0507846 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2499,7 +2499,6 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
* be atomic
*/
bool postcopy_running = postcopy_state_get() >=
POSTCOPY_INCOMING_LISTENING;
- bool need_flush = false;
seq_iter++;
@@ -2534,7 +2533,6 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
/* After going into COLO, we should load the Page into colo_cache
*/
if (ram_cache_enable) {
host = colo_cache_from_block_offset(block, addr);
- need_flush = true;
} else {
host = host_from_ram_block_offset(block, addr);
}
@@ -2629,9 +2627,6 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
wait_for_decompress_done();
rcu_read_unlock();
- if (!ret && ram_cache_enable && need_flush) {
- colo_flush_ram_cache();
- }
DPRINTF("Completed load of VM with exit code %d seq iteration "
"%" PRIu64 "\n", ret, seq_iter);
return ret;
diff --git a/migration/savevm.c b/migration/savevm.c
index 9085338..2d7a7ae 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -912,6 +912,10 @@ void qemu_savevm_state_begin(QEMUFile *f,
break;
}
}
+ if (migration_in_colo_state()) {
+ qemu_put_byte(f, QEMU_VM_EOF);
+ qemu_fflush(f);
+ }
}
/*
--
1.8.3.1
