savevm: split save_live into stage2 and stage3

We split it into 2 functions, foo_live_iterate, and foo_live_complete.
At this point, we only remove the bits that are for the other stage,
functionally this is equivalent to previous code.

Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
Juan Quintela 2012-06-28 15:31:37 +02:00
parent d1315aac6e
commit 16310a3cca
4 changed files with 128 additions and 68 deletions

View File

@ -374,12 +374,13 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
return 0;
}
static int ram_save_live(QEMUFile *f, int stage, void *opaque)
static int ram_save_iterate(QEMUFile *f, void *opaque)
{
uint64_t bytes_transferred_last;
double bwidth = 0;
int ret;
int i;
uint64_t expected_time;
memory_global_sync_dirty_bitmap(get_system_memory());
@ -424,28 +425,64 @@ static int ram_save_live(QEMUFile *f, int stage, void *opaque)
bwidth = 0.000001;
}
/* try transferring iterative blocks of memory */
if (stage == 3) {
int bytes_sent;
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
/* flush all remaining blocks regardless of rate limiting */
while ((bytes_sent = ram_save_block(f)) != 0) {
bytes_transferred += bytes_sent;
expected_time = ram_save_remaining() * TARGET_PAGE_SIZE / bwidth;
DPRINTF("ram_save_live: expected(" PRIu64 ") <= max(" PRIu64 ")?\n",
expected_time, migrate_max_downtime());
return expected_time <= migrate_max_downtime();
}
static int ram_save_complete(QEMUFile *f, void *opaque)
{
double bwidth = 0;
int ret;
int i;
int bytes_sent;
memory_global_sync_dirty_bitmap(get_system_memory());
bwidth = qemu_get_clock_ns(rt_clock);
i = 0;
while ((ret = qemu_file_rate_limit(f)) == 0) {
bytes_sent = ram_save_block(f);
bytes_transferred += bytes_sent;
if (bytes_sent == 0) { /* no more blocks */
break;
}
memory_global_dirty_log_stop();
/* we want to check in the 1st loop, just in case it was the 1st time
and we had to sync the dirty bitmap.
qemu_get_clock_ns() is a bit expensive, so we only check each some
iterations
*/
if ((i & 63) == 0) {
uint64_t t1 = (qemu_get_clock_ns(rt_clock) - bwidth) / 1000000;
if (t1 > MAX_WAIT) {
DPRINTF("big wait: " PRIu64 " milliseconds, %d iterations\n",
t1, i);
break;
}
}
i++;
}
if (ret < 0) {
return ret;
}
/* try transferring iterative blocks of memory */
/* flush all remaining blocks regardless of rate limiting */
while ((bytes_sent = ram_save_block(f)) != 0) {
bytes_transferred += bytes_sent;
}
memory_global_dirty_log_stop();
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
if (stage == 2) {
uint64_t expected_time;
expected_time = ram_save_remaining() * TARGET_PAGE_SIZE / bwidth;
DPRINTF("ram_save_live: expected(" PRIu64 ") <= max(" PRIu64 ")?\n",
expected_time, migrate_max_downtime());
return expected_time <= migrate_max_downtime();
}
return 0;
}
@ -578,7 +615,8 @@ done:
SaveVMHandlers savevm_ram_handlers = {
.save_live_setup = ram_save_setup,
.save_live_state = ram_save_live,
.save_live_iterate = ram_save_iterate,
.save_live_complete = ram_save_complete,
.load_state = ram_load,
.cancel = ram_migration_cancel,
};

View File

@ -568,12 +568,12 @@ static int block_save_setup(QEMUFile *f, void *opaque)
return 0;
}
static int block_save_live(QEMUFile *f, int stage, void *opaque)
static int block_save_iterate(QEMUFile *f, void *opaque)
{
int ret;
DPRINTF("Enter save live stage %d submitted %d transferred %d\n",
stage, block_mig_state.submitted, block_mig_state.transferred);
DPRINTF("Enter save live iterate submitted %d transferred %d\n",
block_mig_state.submitted, block_mig_state.transferred);
flush_blks(f);
@ -585,56 +585,76 @@ static int block_save_live(QEMUFile *f, int stage, void *opaque)
blk_mig_reset_dirty_cursor();
if (stage == 2) {
/* control the rate of transfer */
while ((block_mig_state.submitted +
block_mig_state.read_done) * BLOCK_SIZE <
qemu_file_get_rate_limit(f)) {
if (block_mig_state.bulk_completed == 0) {
/* first finish the bulk phase */
if (blk_mig_save_bulked_block(f) == 0) {
/* finished saving bulk on all devices */
block_mig_state.bulk_completed = 1;
}
} else {
if (blk_mig_save_dirty_block(f, 1) == 0) {
/* no more dirty blocks */
break;
}
/* control the rate of transfer */
while ((block_mig_state.submitted +
block_mig_state.read_done) * BLOCK_SIZE <
qemu_file_get_rate_limit(f)) {
if (block_mig_state.bulk_completed == 0) {
/* first finish the bulk phase */
if (blk_mig_save_bulked_block(f) == 0) {
/* finished saving bulk on all devices */
block_mig_state.bulk_completed = 1;
}
} else {
if (blk_mig_save_dirty_block(f, 1) == 0) {
/* no more dirty blocks */
break;
}
}
flush_blks(f);
ret = qemu_file_get_error(f);
if (ret) {
blk_mig_cleanup();
return ret;
}
}
if (stage == 3) {
/* we know for sure that save bulk is completed and
all async read completed */
assert(block_mig_state.submitted == 0);
flush_blks(f);
while (blk_mig_save_dirty_block(f, 0) != 0);
ret = qemu_file_get_error(f);
if (ret) {
blk_mig_cleanup();
/* report completion */
qemu_put_be64(f, (100 << BDRV_SECTOR_BITS) | BLK_MIG_FLAG_PROGRESS);
ret = qemu_file_get_error(f);
if (ret) {
return ret;
}
DPRINTF("Block migration completed\n");
return ret;
}
qemu_put_be64(f, BLK_MIG_FLAG_EOS);
return ((stage == 2) && is_stage2_completed());
return is_stage2_completed();
}
static int block_save_complete(QEMUFile *f, void *opaque)
{
int ret;
DPRINTF("Enter save live complete submitted %d transferred %d\n",
block_mig_state.submitted, block_mig_state.transferred);
flush_blks(f);
ret = qemu_file_get_error(f);
if (ret) {
blk_mig_cleanup();
return ret;
}
blk_mig_reset_dirty_cursor();
/* we know for sure that save bulk is completed and
all async read completed */
assert(block_mig_state.submitted == 0);
while (blk_mig_save_dirty_block(f, 0) != 0) {
/* Do nothing */
}
blk_mig_cleanup();
/* report completion */
qemu_put_be64(f, (100 << BDRV_SECTOR_BITS) | BLK_MIG_FLAG_PROGRESS);
ret = qemu_file_get_error(f);
if (ret) {
return ret;
}
DPRINTF("Block migration completed\n");
qemu_put_be64(f, BLK_MIG_FLAG_EOS);
return 0;
}
static int block_load(QEMUFile *f, void *opaque, int version_id)
@ -731,7 +751,8 @@ static bool block_is_active(void *opaque)
SaveVMHandlers savevm_block_handlers = {
.set_params = block_set_params,
.save_live_setup = block_save_setup,
.save_live_state = block_save_live,
.save_live_iterate = block_save_iterate,
.save_live_complete = block_save_complete,
.load_state = block_load,
.cancel = block_migration_cancel,
.is_active = block_is_active,

View File

@ -1236,7 +1236,7 @@ int register_savevm_live(DeviceState *dev,
se->vmsd = NULL;
se->no_migrate = 0;
/* if this is a live_savem then set is_ram */
if (ops->save_live_state != NULL) {
if (ops->save_live_setup != NULL) {
se->is_ram = 1;
}
@ -1620,7 +1620,7 @@ int qemu_savevm_state_iterate(QEMUFile *f)
int ret = 1;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!se->ops || !se->ops->save_live_state) {
if (!se->ops || !se->ops->save_live_iterate) {
continue;
}
if (se->ops && se->ops->is_active) {
@ -1636,7 +1636,7 @@ int qemu_savevm_state_iterate(QEMUFile *f)
qemu_put_byte(f, QEMU_VM_SECTION_PART);
qemu_put_be32(f, se->section_id);
ret = se->ops->save_live_state(f, QEMU_VM_SECTION_PART, se->opaque);
ret = se->ops->save_live_iterate(f, se->opaque);
trace_savevm_section_end(se->section_id);
if (ret <= 0) {
@ -1665,7 +1665,7 @@ int qemu_savevm_state_complete(QEMUFile *f)
cpu_synchronize_all_states();
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!se->ops || !se->ops->save_live_state) {
if (!se->ops || !se->ops->save_live_complete) {
continue;
}
if (se->ops && se->ops->is_active) {
@ -1678,7 +1678,7 @@ int qemu_savevm_state_complete(QEMUFile *f)
qemu_put_byte(f, QEMU_VM_SECTION_END);
qemu_put_be32(f, se->section_id);
ret = se->ops->save_live_state(f, QEMU_VM_SECTION_END, se->opaque);
ret = se->ops->save_live_complete(f, se->opaque);
trace_savevm_section_end(se->section_id);
if (ret < 0) {
return ret;

View File

@ -33,7 +33,8 @@ typedef struct SaveVMHandlers {
void (*set_params)(const MigrationParams *params, void * opaque);
SaveStateHandler *save_state;
int (*save_live_setup)(QEMUFile *f, void *opaque);
int (*save_live_state)(QEMUFile *f, int stage, void *opaque);
int (*save_live_iterate)(QEMUFile *f, void *opaque);
int (*save_live_complete)(QEMUFile *f, void *opaque);
void (*cancel)(void *opaque);
LoadStateHandler *load_state;
bool (*is_active)(void *opaque);