* Daniel P. Berrangé (berra...@redhat.com) wrote:
> The VM stop process has to flush outstanding I/O and this is a critical
> failure scenario that is hard to diagnose. Add a probe point that
> records the flush return code.
>
> Signed-off-by: Daniel P. Berrangé
Reviewed-by: Dr. David Alan Gilbert
> ---
> softmmu/cpus.c | 7 ++-
> softmmu/trace-events | 3 +++
> 2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/softmmu/cpus.c b/softmmu/cpus.c
> index a7ee431187..c3caaeb26e 100644
> --- a/softmmu/cpus.c
> +++ b/softmmu/cpus.c
> @@ -44,6 +44,7 @@
> #include "sysemu/whpx.h"
> #include "hw/boards.h"
> #include "hw/hw.h"
> +#include "trace.h"
>
> #ifdef CONFIG_LINUX
>
> @@ -266,6 +267,7 @@ static int do_vm_stop(RunState state, bool send_stop)
>
> bdrv_drain_all();
> ret = bdrv_flush_all();
> +trace_vm_stop_flush_all(ret);
>
> return ret;
> }
> @@ -704,12 +706,15 @@ int vm_stop_force_state(RunState state)
> if (runstate_is_running()) {
> return vm_stop(state);
> } else {
> +int ret;
> runstate_set(state);
>
> bdrv_drain_all();
> /* Make sure to return an error if the flush in a previous vm_stop()
> * failed. */
> -return bdrv_flush_all();
> +ret = bdrv_flush_all();
> +trace_vm_stop_flush_all(ret);
> +return ret;
> }
> }
>
> diff --git a/softmmu/trace-events b/softmmu/trace-events
> index b80ca042e1..f11b427544 100644
> --- a/softmmu/trace-events
> +++ b/softmmu/trace-events
> @@ -19,6 +19,9 @@ flatview_new(void *view, void *root) "%p (root %p)"
> flatview_destroy(void *view, void *root) "%p (root %p)"
> flatview_destroy_rcu(void *view, void *root) "%p (root %p)"
>
> +# softmmu.c
> +vm_stop_flush_all(int ret) "ret %d"
> +
> # vl.c
> vm_state_notify(int running, int reason, const char *reason_str) "running %d
> reason %d (%s)"
> load_file(const char *name, const char *path) "name %s location %s"
> --
> 2.30.2
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
