qemu-kvm/kvm-Revert-monitor-use-aio_co_reschedule_self.patch

68 lines
2.8 KiB
Diff

From 53cc7daf2b6356f236a493cbe63d01afc5636fd3 Mon Sep 17 00:00:00 2001
From: Stefan Hajnoczi <stefanha@redhat.com>
Date: Mon, 6 May 2024 15:06:21 -0400
Subject: [PATCH 13/14] Revert "monitor: use aio_co_reschedule_self()"
RH-Author: Kevin Wolf <kwolf@redhat.com>
RH-MergeRequest: 253: Revert "monitor: use aio_co_reschedule_self()"
RH-Jira: RHEL-43409 RHEL-43410
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Hanna Czenczek <hreitz@redhat.com>
RH-Commit: [1/2] 772eccc9da09e6c1793d46ab6cf9ee6615812154 (kmwolf/centos-qemu-kvm)
Commit 1f25c172f837 ("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 <kwolf@redhat.com> 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 1f25c172f83704e350c0829438d832384084a74d.
Cc: qemu-stable@nongnu.org
Buglink: https://issues.redhat.com/browse/RHEL-34618
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240506190622.56095-2-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 719c6819ed9a9838520fa732f9861918dc693bda)
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
qapi/qmp-dispatch.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/qapi/qmp-dispatch.c b/qapi/qmp-dispatch.c
index f3488afeef..176b549473 100644
--- a/qapi/qmp-dispatch.c
+++ b/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 {
/*
--
2.39.3