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Diffstat (limited to 'block-migration.c')
-rw-r--r--block-migration.c54
1 files changed, 51 insertions, 3 deletions
diff --git a/block-migration.c b/block-migration.c
index d62a8b80ba..b726c6c002 100644
--- a/block-migration.c
+++ b/block-migration.c
@@ -54,7 +54,7 @@ typedef struct BlkMigDevState {
int64_t cur_sector;
int64_t cur_dirty;
- /* Protected by iothread lock. */
+ /* Protected by block migration lock. */
unsigned long *aio_bitmap;
int64_t completed_sectors;
} BlkMigDevState;
@@ -69,7 +69,7 @@ typedef struct BlkMigBlock {
QEMUIOVector qiov;
BlockDriverAIOCB *aiocb;
- /* Protected by iothread lock. */
+ /* Protected by block migration lock. */
int ret;
QSIMPLEQ_ENTRY(BlkMigBlock) entry;
} BlkMigBlock;
@@ -81,7 +81,7 @@ typedef struct BlkMigState {
QSIMPLEQ_HEAD(bmds_list, BlkMigDevState) bmds_list;
int64_t total_sector_sum;
- /* Protected by iothread lock. */
+ /* Protected by lock. */
QSIMPLEQ_HEAD(blk_list, BlkMigBlock) blk_list;
int submitted;
int read_done;
@@ -90,10 +90,23 @@ typedef struct BlkMigState {
int transferred;
int prev_progress;
int bulk_completed;
+
+ /* Lock must be taken _inside_ the iothread lock. */
+ QemuMutex lock;
} BlkMigState;
static BlkMigState block_mig_state;
+static void blk_mig_lock(void)
+{
+ qemu_mutex_lock(&block_mig_state.lock);
+}
+
+static void blk_mig_unlock(void)
+{
+ qemu_mutex_unlock(&block_mig_state.lock);
+}
+
static void blk_send(QEMUFile *f, BlkMigBlock * blk)
{
int len;
@@ -120,9 +133,11 @@ uint64_t blk_mig_bytes_transferred(void)
BlkMigDevState *bmds;
uint64_t sum = 0;
+ blk_mig_lock();
QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
sum += bmds->completed_sectors;
}
+ blk_mig_unlock();
return sum << BDRV_SECTOR_BITS;
}
@@ -142,6 +157,9 @@ uint64_t blk_mig_bytes_total(void)
return sum << BDRV_SECTOR_BITS;
}
+
+/* Called with migration lock held. */
+
static int bmds_aio_inflight(BlkMigDevState *bmds, int64_t sector)
{
int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
@@ -154,6 +172,8 @@ static int bmds_aio_inflight(BlkMigDevState *bmds, int64_t sector)
}
}
+/* Called with migration lock held. */
+
static void bmds_set_aio_inflight(BlkMigDevState *bmds, int64_t sector_num,
int nb_sectors, int set)
{
@@ -188,10 +208,13 @@ static void alloc_aio_bitmap(BlkMigDevState *bmds)
bmds->aio_bitmap = g_malloc0(bitmap_size);
}
+/* Never hold migration lock when yielding to the main loop! */
+
static void blk_mig_read_cb(void *opaque, int ret)
{
BlkMigBlock *blk = opaque;
+ blk_mig_lock();
blk->ret = ret;
QSIMPLEQ_INSERT_TAIL(&block_mig_state.blk_list, blk, entry);
@@ -200,6 +223,7 @@ static void blk_mig_read_cb(void *opaque, int ret)
block_mig_state.submitted--;
block_mig_state.read_done++;
assert(block_mig_state.submitted >= 0);
+ blk_mig_unlock();
}
static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
@@ -244,7 +268,9 @@ static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
+ blk_mig_lock();
block_mig_state.submitted++;
+ blk_mig_unlock();
blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov,
nr_sectors, blk_mig_read_cb, blk);
@@ -366,8 +392,12 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
int ret = -EIO;
for (sector = bmds->cur_dirty; sector < bmds->total_sectors;) {
+ blk_mig_lock();
if (bmds_aio_inflight(bmds, sector)) {
+ blk_mig_unlock();
bdrv_drain_all();
+ } else {
+ blk_mig_unlock();
}
if (bdrv_get_dirty(bmds->bs, sector)) {
@@ -389,8 +419,11 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
blk->aiocb = bdrv_aio_readv(bmds->bs, sector, &blk->qiov,
nr_sectors, blk_mig_read_cb, blk);
+
+ blk_mig_lock();
block_mig_state.submitted++;
bmds_set_aio_inflight(bmds, sector, nr_sectors, 1);
+ blk_mig_unlock();
} else {
ret = bdrv_read(bmds->bs, sector, blk->buf, nr_sectors);
if (ret < 0) {
@@ -446,6 +479,7 @@ static int flush_blks(QEMUFile *f)
__FUNCTION__, block_mig_state.submitted, block_mig_state.read_done,
block_mig_state.transferred);
+ blk_mig_lock();
while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) {
if (qemu_file_rate_limit(f)) {
break;
@@ -456,7 +490,9 @@ static int flush_blks(QEMUFile *f)
}
QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry);
+ blk_mig_unlock();
blk_send(f, blk);
+ blk_mig_lock();
g_free(blk->buf);
g_free(blk);
@@ -465,6 +501,7 @@ static int flush_blks(QEMUFile *f)
block_mig_state.transferred++;
assert(block_mig_state.read_done >= 0);
}
+ blk_mig_unlock();
DPRINTF("%s Exit submitted %d read_done %d transferred %d\n", __FUNCTION__,
block_mig_state.submitted, block_mig_state.read_done,
@@ -493,6 +530,7 @@ static void blk_mig_cleanup(void)
set_dirty_tracking(0);
+ blk_mig_lock();
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);
@@ -506,6 +544,7 @@ static void blk_mig_cleanup(void)
g_free(blk->buf);
g_free(blk);
}
+ blk_mig_unlock();
}
static void block_migration_cancel(void *opaque)
@@ -548,9 +587,11 @@ static int block_save_iterate(QEMUFile *f, void *opaque)
blk_mig_reset_dirty_cursor();
/* control the rate of transfer */
+ blk_mig_lock();
while ((block_mig_state.submitted +
block_mig_state.read_done) * BLOCK_SIZE <
qemu_file_get_rate_limit(f)) {
+ blk_mig_unlock();
if (block_mig_state.bulk_completed == 0) {
/* first finish the bulk phase */
if (blk_mig_save_bulked_block(f) == 0) {
@@ -564,11 +605,13 @@ static int block_save_iterate(QEMUFile *f, void *opaque)
if (ret < 0) {
return ret;
}
+ blk_mig_lock();
if (ret != 0) {
/* no more dirty blocks */
break;
}
}
+ blk_mig_unlock();
ret = flush_blks(f);
if (ret) {
@@ -595,7 +638,9 @@ static int block_save_complete(QEMUFile *f, void *opaque)
/* we know for sure that save bulk is completed and
all async read completed */
+ blk_mig_lock();
assert(block_mig_state.submitted == 0);
+ blk_mig_unlock();
do {
ret = blk_mig_save_dirty_block(f, 0);
@@ -620,6 +665,7 @@ static uint64_t block_save_pending(QEMUFile *f, void *opaque, uint64_t max_size)
/* Estimate pending number of bytes to send */
uint64_t pending;
+ blk_mig_lock();
pending = get_remaining_dirty() +
block_mig_state.submitted * BLOCK_SIZE +
block_mig_state.read_done * BLOCK_SIZE;
@@ -628,6 +674,7 @@ static uint64_t block_save_pending(QEMUFile *f, void *opaque, uint64_t max_size)
if (pending == 0 && !block_mig_state.bulk_completed) {
pending = BLOCK_SIZE;
}
+ blk_mig_unlock();
DPRINTF("Enter save live pending %" PRIu64 "\n", pending);
return pending;
@@ -739,6 +786,7 @@ void blk_mig_init(void)
{
QSIMPLEQ_INIT(&block_mig_state.bmds_list);
QSIMPLEQ_INIT(&block_mig_state.blk_list);
+ qemu_mutex_init(&block_mig_state.lock);
register_savevm_live(NULL, "block", 0, 1, &savevm_block_handlers,
&block_mig_state);
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-14 19:42:05 +0000