@@ -63,6 +63,7 @@ typedef struct MirrorBlockJob {
int ret;
bool unmap;
bool waiting_for_io;
+ bool detached; /* temporarily detached from AioContext, don't do I/O */
int target_cluster_sectors;
int max_iov;
} MirrorBlockJob;
@@ -119,7 +120,7 @@ static void mirror_iteration_done(MirrorOp *op, int ret)
qemu_iovec_destroy(&op->qiov);
g_free(op);
- if (s->waiting_for_io) {
+ if (s->waiting_for_io && !s->detached) {
qemu_coroutine_enter(s->common.co, NULL);
}
}
@@ -375,7 +376,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
assert(!(sector_num % sectors_per_chunk));
ret = bdrv_get_block_status_above(source, NULL, sector_num,
nb_chunks * sectors_per_chunk,
- &io_sectors, &file);
+ &io_sectors, &file); /* TODO blocking */
if (ret < 0) {
io_sectors = nb_chunks * sectors_per_chunk;
}
@@ -442,6 +443,29 @@ static void mirror_drain(MirrorBlockJob *s)
}
}
+static void mirror_attached_aio_context(AioContext *new_context, void *opaque)
+{
+ MirrorBlockJob *s = opaque;
+
+ blk_set_aio_context(s->target, new_context);
+
+ /* Resume execution */
+ s->detached = false;
+ if (s->waiting_for_io) {
+ qemu_coroutine_enter(s->common.co, NULL);
+ }
+}
+
+static void mirror_detach_aio_context(void *opaque)
+{
+ MirrorBlockJob *s = opaque;
+
+ s->detached = true;
+
+ /* Complete pending write requests */
+ blk_drain(s->target);
+}
+
typedef struct {
int ret;
} MirrorExitData;
@@ -491,6 +515,8 @@ static void mirror_exit(BlockJob *job, void *opaque)
if (replace_aio_context) {
aio_context_release(replace_aio_context);
}
+ blk_remove_aio_context_notifier(s->common.blk, mirror_attached_aio_context,
+ mirror_detach_aio_context, s);
g_free(s->replaces);
bdrv_op_unblock_all(target_bs, s->common.blocker);
blk_unref(s->target);
@@ -580,14 +606,14 @@ static void coroutine_fn mirror_run(void *opaque)
if (now - last_pause_ns > SLICE_TIME) {
last_pause_ns = now;
- block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0);
+ block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0); /* TODO blocking */
}
if (block_job_is_cancelled(&s->common)) {
goto immediate_exit;
}
- ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n);
+ ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n); /* TODO blocking */
if (ret < 0) {
goto immediate_exit;
@@ -680,13 +706,13 @@ static void coroutine_fn mirror_run(void *opaque)
ret = 0;
trace_mirror_before_sleep(s, cnt, s->synced, delay_ns);
if (!s->synced) {
- block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
+ block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns); /* TODO blocking */
if (block_job_is_cancelled(&s->common)) {
break;
}
} else if (!should_complete) {
delay_ns = (s->in_flight == 0 && cnt == 0 ? SLICE_TIME : 0);
- block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
+ block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns); /* TODO blocking */
} else if (cnt == 0) {
/* The two disks are in sync. Exit and report successful
* completion.
@@ -851,6 +877,9 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
bdrv_op_block_all(target, s->common.blocker);
+ blk_add_aio_context_notifier(s->common.blk, mirror_attached_aio_context,
+ mirror_detach_aio_context, s);
+
s->common.co = qemu_coroutine_create(mirror_run);
trace_mirror_start(bs, s, s->common.co, opaque);
qemu_coroutine_enter(s->common.co, s);
When dataplane is enabled or disabled the drive switches to a new AioContext. The mirror block job must also move to the new AioContext so that drive accesses are always made within its AioContext. This work-in-progress patch partially achieves that by draining s->target of in-flight write requests to reach a quiescent point. The job is resumed in the new AioContext after moving s->target into the new AioContext. Unsolved cases include block_job_sleep_ns(), bdrv_is_allocated_above(), and bdrv_get_block_status_above(). Currently they continue executing in the old AioContext. Perhaps something similar to block_job_is_cancelled() checking is necessary so the coroutine can move itself to the new AioContext. Cc: Fam Zheng <famz@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> --- Jason: Please try this patch and see if it fixes the abort. It has fixed migration after drive_mirror for me. --- block/mirror.c | 41 +++++++++++++++++++++++++++++++++++------ 1 file changed, 35 insertions(+), 6 deletions(-)