From d76cac7dfbff76acb8eac2de849d148b0ff8cbbb Mon Sep 17 00:00:00 2001 From: Liran Schour Date: Tue, 26 Jan 2010 14:04:11 +0200 Subject: Tranfer dirty blocks during iterative phase Start transfer dirty blocks during the iterative stage. That will reduce the time that the guest will be suspended Signed-off-by: Liran Schour Signed-off-by: Anthony Liguori --- block-migration.c | 135 +++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 99 insertions(+), 36 deletions(-) (limited to 'block-migration.c') diff --git a/block-migration.c b/block-migration.c index 42320b28eb..30705891d0 100644 --- a/block-migration.c +++ b/block-migration.c @@ -42,6 +42,7 @@ typedef struct BlkMigDevState { 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; @@ -70,6 +71,7 @@ typedef struct BlkMigState { int64_t total_sector_sum; int prev_progress; int bulk_completed; + int dirty_iterations; } BlkMigState; static BlkMigState block_mig_state; @@ -183,6 +185,7 @@ static int mig_save_device_bulk(Monitor *mon, QEMUFile *f, goto error; } block_mig_state.submitted++; + bdrv_reset_dirty(bs, cur_sector, nr_sectors); bmds->cur_sector = cur_sector + nr_sectors; @@ -281,39 +284,88 @@ static int blk_mig_save_bulked_block(Monitor *mon, QEMUFile *f) 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 (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; + + 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->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++; + } else { + if (bdrv_read(bmds->bs, sector, blk->buf, + nr_sectors) < 0) { + goto error; } - blk.bmds = bmds; - blk.sector = sector; - blk_send(f, &blk); + blk_send(f, blk); - bdrv_reset_dirty(bmds->bs, sector, - BDRV_SECTORS_PER_DIRTY_CHUNK); + 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) @@ -404,28 +456,39 @@ static int block_save_live(Monitor *mon, QEMUFile *f, int stage, void *opaque) 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) == 0) { - /* finished saving bulk on all devices */ - block_mig_state.bulk_completed = 1; - 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) { + /* finish 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) { /* we know for sure that save bulk is completed */ - blk_mig_save_dirty_blocks(mon, f); + while(blk_mig_save_dirty_block(mon, f, 0) != 0); blk_mig_cleanup(mon); /* report completion */ -- cgit v1.2.3-55-g7522