Revert "monitor: use aio_co_reschedule_self()"

Commit 1f25c17 ("monitor: use aio_co_reschedule_self()") was a code
cleanup that uses aio_co_reschedule_self() instead of open coding
coroutine rescheduling.

Bug RHEL-34618 was reported and Kevin Wolf <[email protected]> identified
the root cause. I missed that aio_co_reschedule_self() ->
qemu_get_current_aio_context() only knows about
qemu_aio_context/IOThread AioContexts and not about iohandler_ctx. It
does not function correctly when going back from the iohandler_ctx to
qemu_aio_context.

Go back to open coding the AioContext transitions to avoid this bug.

This reverts commit 1f25c17.

Cc: [email protected]
Buglink: https://issues.redhat.com/browse/RHEL-34618
Signed-off-by: Stefan Hajnoczi <[email protected]>
Message-ID: <[email protected]>
Reviewed-by: Kevin Wolf <[email protected]>
Signed-off-by: Kevin Wolf <[email protected]>

Author: stefanhaRH

qapi/qmp-dispatch.c

@@ -212,7 +212,8 @@ QDict *coroutine_mixed_fn qmp_dispatch(const QmpCommandList *cmds, QObject *requ
              * executing the command handler so that it can make progress if it
              * involves an AIO_WAIT_WHILE().
              */
-            aio_co_reschedule_self(qemu_get_aio_context());
+            aio_co_schedule(qemu_get_aio_context(), qemu_coroutine_self());
+            qemu_coroutine_yield();
         }
 
         monitor_set_cur(qemu_coroutine_self(), cur_mon);
@@ -226,7 +227,9 @@ QDict *coroutine_mixed_fn qmp_dispatch(const QmpCommandList *cmds, QObject *requ
              * Move back to iohandler_ctx so that nested event loops for
              * qemu_aio_context don't start new monitor commands.
              */
-            aio_co_reschedule_self(iohandler_get_aio_context());
+            aio_co_schedule(iohandler_get_aio_context(),
+                            qemu_coroutine_self());
+            qemu_coroutine_yield();
         }
     } else {
        /*