For simplicity, use bdrv_drained_begin/end to avoid concurrent writes to the write threshold, or reading it while it is being set. qmp_block_set_write_threshold is protected by the BQL.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- block/write-threshold.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/block/write-threshold.c b/block/write-threshold.c index c8ebc32b4d..64ddd3d653 100644 --- a/block/write-threshold.c +++ b/block/write-threshold.c @@ -112,7 +112,6 @@ void qmp_block_set_write_threshold(const char *node_name, Error **errp) { BlockDriverState *bs; - AioContext *aio_context; bs = bdrv_find_node(node_name); if (!bs) { @@ -120,10 +119,8 @@ void qmp_block_set_write_threshold(const char *node_name, return; } - aio_context = bdrv_get_aio_context(bs); - aio_context_acquire(aio_context); - + /* Avoid a concurrent write_threshold_disable. */ + bdrv_drained_begin(bs); bdrv_write_threshold_set(bs, threshold_bytes); - - aio_context_release(aio_context); + bdrv_drained_end(bs); } -- 2.13.0