Thanks for the update. I have sent the v3 removing the irrelevant
information:
https://patchew.org/QEMU/20231205091903.3640-1-tian...@smartx.com/
Best,
Tianren Zhang
On Tue, Dec 5, 2023 at 4:14 PM Daniel P. Berrangé <berra...@redhat.com>
wrote:
> On Tue, Dec 05, 2023 at 01:48:26AM -0500, tian...@smartx.com wrote:
> > From: Tianren Zhang <tian...@smartx.com>
> >
> > The stop process is not finished until bdrv_flush_all
> > is done. Some users (e.g., libvirt) detect the STOP
> > event and invokes some lock release logic to revoke
> > the disk lock held by current qemu when such event is
> > emitted. In such case, if the bdrv_flush_all is after
> > the stop event, it's possible that the disk lock is
> > released while the qemu is still waiting for I/O.
> > Therefore, it's better to have the stop event generated
> > after the whole stop process is done, so we can
> > guarantee to users that the stop process is finished
> > when they get the STOP event.
> >
> > Change-Id: Ia2f95cd55edfdeb71ee2e04005ac216cfabffa22
>
> Please don't include this in commit messages for patches posted.
> QEMU does not use Gerrit and so this is irrelevant to upstream.
>
> > Signed-off-by: Tianren Zhang <tian...@smartx.com>
> > ---
> > v2: do not call runstate_is_running twice
> > ---
> > system/cpus.c | 9 ++++++---
> > 1 file changed, 6 insertions(+), 3 deletions(-)
>
> Reviewed-by: Daniel P. Berrangé <berra...@redhat.com>
>
> >
> > diff --git a/system/cpus.c b/system/cpus.c
> > index a444a747f0..49af0f92b5 100644
> > --- a/system/cpus.c
> > +++ b/system/cpus.c
> > @@ -262,21 +262,24 @@ void cpu_interrupt(CPUState *cpu, int mask)
> > static int do_vm_stop(RunState state, bool send_stop)
> > {
> > int ret = 0;
> > + bool do_send_stop = false;
> >
> > if (runstate_is_running()) {
> > runstate_set(state);
> > cpu_disable_ticks();
> > pause_all_vcpus();
> > vm_state_notify(0, state);
> > - if (send_stop) {
> > - qapi_event_send_stop();
> > - }
> > + do_send_stop = send_stop;
> > }
> >
> > bdrv_drain_all();
> > ret = bdrv_flush_all();
> > trace_vm_stop_flush_all(ret);
> >
> > + if (do_send_stop) {
> > + qapi_event_send_stop();
> > + }
> > +
> > return ret;
> > }
>
> With regards,
> Daniel
> --
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