softmmu: add trace point when bdrv_flush_all fails

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.

Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2021-04-15 14:33:51 +01:00
parent 626ff6515d
commit 8af3f5c6d6
2 changed files with 9 additions and 1 deletions

View File

@ -44,6 +44,7 @@
#include "sysemu/whpx.h" #include "sysemu/whpx.h"
#include "hw/boards.h" #include "hw/boards.h"
#include "hw/hw.h" #include "hw/hw.h"
#include "trace.h"
#ifdef CONFIG_LINUX #ifdef CONFIG_LINUX
@ -266,6 +267,7 @@ static int do_vm_stop(RunState state, bool send_stop)
bdrv_drain_all(); bdrv_drain_all();
ret = bdrv_flush_all(); ret = bdrv_flush_all();
trace_vm_stop_flush_all(ret);
return ret; return ret;
} }
@ -704,12 +706,15 @@ int vm_stop_force_state(RunState state)
if (runstate_is_running()) { if (runstate_is_running()) {
return vm_stop(state); return vm_stop(state);
} else { } else {
int ret;
runstate_set(state); runstate_set(state);
bdrv_drain_all(); bdrv_drain_all();
/* Make sure to return an error if the flush in a previous vm_stop() /* Make sure to return an error if the flush in a previous vm_stop()
* failed. */ * failed. */
return bdrv_flush_all(); ret = bdrv_flush_all();
trace_vm_stop_flush_all(ret);
return ret;
} }
} }

View File

@ -19,6 +19,9 @@ flatview_new(void *view, void *root) "%p (root %p)"
flatview_destroy(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)" flatview_destroy_rcu(void *view, void *root) "%p (root %p)"
# softmmu.c
vm_stop_flush_all(int ret) "ret %d"
# vl.c # vl.c
vm_state_notify(int running, int reason, const char *reason_str) "running %d reason %d (%s)" 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" load_file(const char *name, const char *path) "name %s location %s"