| Message ID | 20210415135851.862406-3-berrange@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | block, migration: improve debugging of migration bdrv_flush failure | expand |
* Daniel P. Berrangé (berrange@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 <berrange@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > --- > 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 >
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"
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 <berrange@redhat.com> --- softmmu/cpus.c | 7 ++++++- softmmu/trace-events | 3 +++ 2 files changed, 9 insertions(+), 1 deletion(-)