#include "block_int.h"
#include "hw/hw.h"
#include "qemu-queue.h"
+#include "qemu-timer.h"
#include "monitor.h"
#include "block-migration.h"
+#include "migration.h"
+#include "blockdev.h"
#include <assert.h>
#define BLOCK_SIZE (BDRV_SECTORS_PER_DIRTY_CHUNK << BDRV_SECTOR_BITS)
#define BLK_MIG_FLAG_PROGRESS 0x04
#define MAX_IS_ALLOCATED_SEARCH 65536
-#define MAX_BLOCKS_READ 10000
-#define BLOCKS_READ_CHANGE 100
-#define INITIAL_BLOCKS_READ 100
//#define DEBUG_BLK_MIGRATION
int bulk_completed;
int shared_base;
int64_t cur_sector;
+ int64_t cur_dirty;
int64_t completed_sectors;
int64_t total_sectors;
int64_t dirty;
QSIMPLEQ_ENTRY(BlkMigDevState) entry;
+ unsigned long *aio_bitmap;
} BlkMigDevState;
typedef struct BlkMigBlock {
uint8_t *buf;
BlkMigDevState *bmds;
int64_t sector;
+ int nr_sectors;
struct iovec iov;
QEMUIOVector qiov;
BlockDriverAIOCB *aiocb;
int transferred;
int64_t total_sector_sum;
int prev_progress;
+ int bulk_completed;
+ long double total_time;
+ long double prev_time_offset;
+ int reads;
} BlkMigState;
static BlkMigState block_mig_state;
return sum << BDRV_SECTOR_BITS;
}
+static inline long double compute_read_bwidth(void)
+{
+ assert(block_mig_state.total_time != 0);
+ return (block_mig_state.reads / block_mig_state.total_time) * BLOCK_SIZE;
+}
+
+static int bmds_aio_inflight(BlkMigDevState *bmds, int64_t sector)
+{
+ int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
+
+ if ((sector << BDRV_SECTOR_BITS) < bdrv_getlength(bmds->bs)) {
+ return !!(bmds->aio_bitmap[chunk / (sizeof(unsigned long) * 8)] &
+ (1UL << (chunk % (sizeof(unsigned long) * 8))));
+ } else {
+ return 0;
+ }
+}
+
+static void bmds_set_aio_inflight(BlkMigDevState *bmds, int64_t sector_num,
+ int nb_sectors, int set)
+{
+ int64_t start, end;
+ unsigned long val, idx, bit;
+
+ start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK;
+ end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK;
+
+ for (; start <= end; start++) {
+ idx = start / (sizeof(unsigned long) * 8);
+ bit = start % (sizeof(unsigned long) * 8);
+ val = bmds->aio_bitmap[idx];
+ if (set) {
+ val |= 1UL << bit;
+ } else {
+ val &= ~(1UL << bit);
+ }
+ bmds->aio_bitmap[idx] = val;
+ }
+}
+
+static void alloc_aio_bitmap(BlkMigDevState *bmds)
+{
+ BlockDriverState *bs = bmds->bs;
+ int64_t bitmap_size;
+
+ bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) +
+ BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1;
+ bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8;
+
+ bmds->aio_bitmap = qemu_mallocz(bitmap_size);
+}
+
static void blk_mig_read_cb(void *opaque, int ret)
{
+ long double curr_time = qemu_get_clock_ns(rt_clock);
BlkMigBlock *blk = opaque;
blk->ret = ret;
+ block_mig_state.reads++;
+ block_mig_state.total_time += (curr_time - block_mig_state.prev_time_offset);
+ block_mig_state.prev_time_offset = curr_time;
+
QSIMPLEQ_INSERT_TAIL(&block_mig_state.blk_list, blk, entry);
+ bmds_set_aio_inflight(blk->bmds, blk->sector, blk->nr_sectors, 0);
block_mig_state.submitted--;
block_mig_state.read_done++;
}
static int mig_save_device_bulk(Monitor *mon, QEMUFile *f,
- BlkMigDevState *bmds, int is_async)
+ BlkMigDevState *bmds)
{
int64_t total_sectors = bmds->total_sectors;
int64_t cur_sector = bmds->cur_sector;
blk->buf = qemu_malloc(BLOCK_SIZE);
blk->bmds = bmds;
blk->sector = cur_sector;
+ blk->nr_sectors = nr_sectors;
- if (is_async) {
- blk->iov.iov_base = blk->buf;
- blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
- qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
+ blk->iov.iov_base = blk->buf;
+ blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
+ qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
- blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov,
- nr_sectors, blk_mig_read_cb, blk);
- if (!blk->aiocb) {
- goto error;
- }
- block_mig_state.submitted++;
- } else {
- if (bdrv_read(bs, cur_sector, blk->buf, nr_sectors) < 0) {
- goto error;
- }
- blk_send(f, blk);
+ if (block_mig_state.submitted == 0) {
+ block_mig_state.prev_time_offset = qemu_get_clock_ns(rt_clock);
+ }
- qemu_free(blk->buf);
- qemu_free(blk);
+ blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov,
+ nr_sectors, blk_mig_read_cb, blk);
+ if (!blk->aiocb) {
+ goto error;
}
+ block_mig_state.submitted++;
bdrv_reset_dirty(bs, cur_sector, nr_sectors);
bmds->cur_sector = cur_sector + nr_sectors;
}
}
-static void init_blk_migration(Monitor *mon, QEMUFile *f)
+static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
{
+ Monitor *mon = opaque;
BlkMigDevState *bmds;
- BlockDriverState *bs;
int64_t sectors;
+ if (!bdrv_is_read_only(bs)) {
+ sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+ if (sectors <= 0) {
+ return;
+ }
+
+ bmds = qemu_mallocz(sizeof(BlkMigDevState));
+ bmds->bs = bs;
+ bmds->bulk_completed = 0;
+ bmds->total_sectors = sectors;
+ bmds->completed_sectors = 0;
+ bmds->shared_base = block_mig_state.shared_base;
+ alloc_aio_bitmap(bmds);
+ drive_get_ref(drive_get_by_blockdev(bs));
+ bdrv_set_in_use(bs, 1);
+
+ block_mig_state.total_sector_sum += sectors;
+
+ if (bmds->shared_base) {
+ monitor_printf(mon, "Start migration for %s with shared base "
+ "image\n",
+ bs->device_name);
+ } else {
+ monitor_printf(mon, "Start full migration for %s\n",
+ bs->device_name);
+ }
+
+ QSIMPLEQ_INSERT_TAIL(&block_mig_state.bmds_list, bmds, entry);
+ }
+}
+
+static void init_blk_migration(Monitor *mon, QEMUFile *f)
+{
block_mig_state.submitted = 0;
block_mig_state.read_done = 0;
block_mig_state.transferred = 0;
block_mig_state.total_sector_sum = 0;
block_mig_state.prev_progress = -1;
+ block_mig_state.bulk_completed = 0;
+ block_mig_state.total_time = 0;
+ block_mig_state.reads = 0;
- for (bs = bdrv_first; bs != NULL; bs = bs->next) {
- if (bs->type == BDRV_TYPE_HD) {
- sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
- if (sectors == 0) {
- continue;
- }
-
- bmds = qemu_mallocz(sizeof(BlkMigDevState));
- bmds->bs = bs;
- bmds->bulk_completed = 0;
- bmds->total_sectors = sectors;
- bmds->completed_sectors = 0;
- bmds->shared_base = block_mig_state.shared_base;
-
- block_mig_state.total_sector_sum += sectors;
-
- if (bmds->shared_base) {
- monitor_printf(mon, "Start migration for %s with shared base "
- "image\n",
- bs->device_name);
- } else {
- monitor_printf(mon, "Start full migration for %s\n",
- bs->device_name);
- }
-
- QSIMPLEQ_INSERT_TAIL(&block_mig_state.bmds_list, bmds, entry);
- }
- }
+ bdrv_iterate(init_blk_migration_it, mon);
}
-static int blk_mig_save_bulked_block(Monitor *mon, QEMUFile *f, int is_async)
+static int blk_mig_save_bulked_block(Monitor *mon, QEMUFile *f)
{
int64_t completed_sector_sum = 0;
BlkMigDevState *bmds;
QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
if (bmds->bulk_completed == 0) {
- if (mig_save_device_bulk(mon, f, bmds, is_async) == 1) {
+ if (mig_save_device_bulk(mon, f, bmds) == 1) {
/* completed bulk section for this device */
bmds->bulk_completed = 1;
}
}
}
- progress = completed_sector_sum * 100 / block_mig_state.total_sector_sum;
+ if (block_mig_state.total_sector_sum != 0) {
+ progress = completed_sector_sum * 100 /
+ block_mig_state.total_sector_sum;
+ } else {
+ progress = 100;
+ }
if (progress != block_mig_state.prev_progress) {
block_mig_state.prev_progress = progress;
qemu_put_be64(f, (progress << BDRV_SECTOR_BITS)
return ret;
}
-#define MAX_NUM_BLOCKS 4
-
-static void blk_mig_save_dirty_blocks(Monitor *mon, QEMUFile *f)
+static void blk_mig_reset_dirty_cursor(void)
{
BlkMigDevState *bmds;
- BlkMigBlock blk;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ bmds->cur_dirty = 0;
+ }
+}
+
+static int mig_save_device_dirty(Monitor *mon, QEMUFile *f,
+ BlkMigDevState *bmds, int is_async)
+{
+ BlkMigBlock *blk;
+ int64_t total_sectors = bmds->total_sectors;
int64_t sector;
+ int nr_sectors;
- blk.buf = qemu_malloc(BLOCK_SIZE);
+ for (sector = bmds->cur_dirty; sector < bmds->total_sectors;) {
+ if (bmds_aio_inflight(bmds, sector)) {
+ qemu_aio_flush();
+ }
+ if (bdrv_get_dirty(bmds->bs, sector)) {
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- for (sector = 0; sector < bmds->cur_sector;) {
- if (bdrv_get_dirty(bmds->bs, sector)) {
- if (bdrv_read(bmds->bs, sector, blk.buf,
- BDRV_SECTORS_PER_DIRTY_CHUNK) < 0) {
- monitor_printf(mon, "Error reading sector %" PRId64 "\n",
- sector);
- qemu_file_set_error(f);
- qemu_free(blk.buf);
- return;
+ if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
+ nr_sectors = total_sectors - sector;
+ } else {
+ nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
+ }
+ blk = qemu_malloc(sizeof(BlkMigBlock));
+ blk->buf = qemu_malloc(BLOCK_SIZE);
+ blk->bmds = bmds;
+ blk->sector = sector;
+ blk->nr_sectors = nr_sectors;
+
+ if (is_async) {
+ blk->iov.iov_base = blk->buf;
+ blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
+ qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
+
+ if (block_mig_state.submitted == 0) {
+ block_mig_state.prev_time_offset = qemu_get_clock_ns(rt_clock);
}
- blk.bmds = bmds;
- blk.sector = sector;
- blk_send(f, &blk);
- bdrv_reset_dirty(bmds->bs, sector,
- BDRV_SECTORS_PER_DIRTY_CHUNK);
+ blk->aiocb = bdrv_aio_readv(bmds->bs, sector, &blk->qiov,
+ nr_sectors, blk_mig_read_cb, blk);
+ if (!blk->aiocb) {
+ goto error;
+ }
+ block_mig_state.submitted++;
+ bmds_set_aio_inflight(bmds, sector, nr_sectors, 1);
+ } else {
+ if (bdrv_read(bmds->bs, sector, blk->buf,
+ nr_sectors) < 0) {
+ goto error;
+ }
+ blk_send(f, blk);
+
+ qemu_free(blk->buf);
+ qemu_free(blk);
}
- sector += BDRV_SECTORS_PER_DIRTY_CHUNK;
+
+ bdrv_reset_dirty(bmds->bs, sector, nr_sectors);
+ break;
}
+ sector += BDRV_SECTORS_PER_DIRTY_CHUNK;
+ bmds->cur_dirty = sector;
}
- qemu_free(blk.buf);
+ return (bmds->cur_dirty >= bmds->total_sectors);
+
+error:
+ monitor_printf(mon, "Error reading sector %" PRId64 "\n", sector);
+ qemu_file_set_error(f);
+ qemu_free(blk->buf);
+ qemu_free(blk);
+ return 0;
+}
+
+static int blk_mig_save_dirty_block(Monitor *mon, QEMUFile *f, int is_async)
+{
+ BlkMigDevState *bmds;
+ int ret = 0;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ if (mig_save_device_dirty(mon, f, bmds, is_async) == 0) {
+ ret = 1;
+ break;
+ }
+ }
+
+ return ret;
}
static void flush_blks(QEMUFile* f)
block_mig_state.transferred);
}
-static int is_stage2_completed(void)
+static int64_t get_remaining_dirty(void)
{
BlkMigDevState *bmds;
+ int64_t dirty = 0;
- if (block_mig_state.submitted > 0) {
- return 0;
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ dirty += bdrv_get_dirty_count(bmds->bs);
}
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- if (bmds->bulk_completed == 0) {
- return 0;
+ return dirty * BLOCK_SIZE;
+}
+
+static int is_stage2_completed(void)
+{
+ int64_t remaining_dirty;
+ long double bwidth;
+
+ if (block_mig_state.bulk_completed == 1) {
+
+ remaining_dirty = get_remaining_dirty();
+ if (remaining_dirty == 0) {
+ return 1;
+ }
+
+ bwidth = compute_read_bwidth();
+
+ if ((remaining_dirty / bwidth) <=
+ migrate_max_downtime()) {
+ /* finish stage2 because we think that we can finish remaing work
+ below max_downtime */
+
+ return 1;
}
}
- return 1;
+ return 0;
}
static void blk_mig_cleanup(Monitor *mon)
BlkMigDevState *bmds;
BlkMigBlock *blk;
+ set_dirty_tracking(0);
+
while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
+ bdrv_set_in_use(bmds->bs, 0);
+ drive_put_ref(drive_get_by_blockdev(bmds->bs));
+ qemu_free(bmds->aio_bitmap);
qemu_free(bmds);
}
qemu_free(blk);
}
- set_dirty_tracking(0);
-
monitor_printf(mon, "\n");
}
return 0;
}
- /* control the rate of transfer */
- while ((block_mig_state.submitted +
- block_mig_state.read_done) * BLOCK_SIZE <
- qemu_file_get_rate_limit(f)) {
- if (blk_mig_save_bulked_block(mon, f, 1) == 0) {
- /* no more bulk blocks for now */
- break;
+ 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(mon, f) == 0) {
+ /* finished saving bulk on all devices */
+ block_mig_state.bulk_completed = 1;
+ }
+ } else {
+ if (blk_mig_save_dirty_block(mon, f, 1) == 0) {
+ /* no more dirty blocks */
+ break;
+ }
+ }
}
- }
- flush_blks(f);
+ flush_blks(f);
- if (qemu_file_has_error(f)) {
- blk_mig_cleanup(mon);
- return 0;
+ if (qemu_file_has_error(f)) {
+ blk_mig_cleanup(mon);
+ return 0;
+ }
}
if (stage == 3) {
- while (blk_mig_save_bulked_block(mon, f, 0) != 0) {
- /* empty */
- }
+ /* we know for sure that save bulk is completed and
+ all async read completed */
+ assert(block_mig_state.submitted == 0);
- blk_mig_save_dirty_blocks(mon, f);
+ while (blk_mig_save_dirty_block(mon, f, 0) != 0);
blk_mig_cleanup(mon);
/* report completion */
int len, flags;
char device_name[256];
int64_t addr;
- BlockDriverState *bs;
+ BlockDriverState *bs, *bs_prev = NULL;
uint8_t *buf;
+ int64_t total_sectors = 0;
+ int nr_sectors;
do {
addr = qemu_get_be64(f);
addr >>= BDRV_SECTOR_BITS;
if (flags & BLK_MIG_FLAG_DEVICE_BLOCK) {
+ int ret;
/* get device name */
len = qemu_get_byte(f);
qemu_get_buffer(f, (uint8_t *)device_name, len);
return -EINVAL;
}
+ if (bs != bs_prev) {
+ bs_prev = bs;
+ total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+ if (total_sectors <= 0) {
+ error_report("Error getting length of block device %s",
+ device_name);
+ return -EINVAL;
+ }
+ }
+
+ if (total_sectors - addr < BDRV_SECTORS_PER_DIRTY_CHUNK) {
+ nr_sectors = total_sectors - addr;
+ } else {
+ nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
+ }
+
buf = qemu_malloc(BLOCK_SIZE);
qemu_get_buffer(f, buf, BLOCK_SIZE);
- bdrv_write(bs, addr, buf, BDRV_SECTORS_PER_DIRTY_CHUNK);
+ ret = bdrv_write(bs, addr, buf, nr_sectors);
qemu_free(buf);
+ if (ret < 0) {
+ return ret;
+ }
} else if (flags & BLK_MIG_FLAG_PROGRESS) {
if (!banner_printed) {
printf("Receiving block device images\n");
QSIMPLEQ_INIT(&block_mig_state.bmds_list);
QSIMPLEQ_INIT(&block_mig_state.blk_list);
- register_savevm_live("block", 0, 1, block_set_params, block_save_live,
- NULL, block_load, &block_mig_state);
+ register_savevm_live(NULL, "block", 0, 1, block_set_params,
+ block_save_live, NULL, block_load, &block_mig_state);
}
projects / qemu.git / blobdiff