Re: [Qemu-devel] [PATCH 1/8] Introduce the VMStatus type

[Luiz Capitulino]

On Tue, 12 Jul 2011 09:28:05 +0200
Markus Armbruster <address@hidden> wrote:

> Luiz Capitulino <address@hidden> writes:
> 
> > We need to track the VM status so that QMP can report it to clients.
> >
> > This commit adds the VMStatus type and related functions. The
> > vm_status_set() function is used to keep track of the current
> > VM status.
> >
> > The current statuses are:
> 
> Nitpicking about names, bear with me.
> 
> >     - debug: guest is running under gdb
> >     - inmigrate: guest is paused waiting for an incoming migration
> 
> incoming-migration?
> 
> >     - postmigrate: guest is paused following a successful migration
> 
> post-migrate?
> 
> >     - internal-error: Fatal internal error that prevents further guest
> >                 execution
> >     - load-state-error: guest is paused following a failed 'loadvm'
> 
> Less than obvious.  If you like concrete, name it loadvm-failed.  If you
> like abstract, name it restore-vm-failed.

Ok for your suggestions above.

> 
> >     - io-error: the last IOP has failed and the device is configured
> >                 to pause on I/O errors
> >     - watchdog-error: the watchdog action is configured to pause and
> >                       has been triggered
> 
> Sounds like the watchdog suffered an error.  watchdog-fired?

Maybe watchdog-paused.

> 
> >     - paused: guest has been paused via the 'stop' command
> 
> stop-command?

I prefer 'paused', it communicates better the state we're in.

> 
> >     - prelaunch: QEMU was started with -S and guest has not started
> 
> unstarted?

Looks the same to me.

> 
> >     - running: guest is actively running
> >     - shutdown: guest is shut down (and -no-shutdown is in use)
> >
> > Signed-off-by: Luiz Capitulino <address@hidden>
> > ---
> >  gdbstub.c       |    4 ++++
> >  hw/ide/core.c   |    1 +
> >  hw/scsi-disk.c  |    1 +
> >  hw/virtio-blk.c |    1 +
> >  hw/watchdog.c   |    1 +
> >  kvm-all.c       |    1 +
> >  migration.c     |    3 +++
> >  monitor.c       |    5 ++++-
> >  sysemu.h        |   19 +++++++++++++++++++
> >  vl.c            |   37 +++++++++++++++++++++++++++++++++++++
> >  10 files changed, 72 insertions(+), 1 deletions(-)
> >
> > diff --git a/gdbstub.c b/gdbstub.c
> > index c085a5a..61b700a 100644
> > --- a/gdbstub.c
> > +++ b/gdbstub.c
> > @@ -2358,6 +2358,7 @@ void gdb_do_syscall(gdb_syscall_complete_cb cb, const 
> > char *fmt, ...)
> >      s->state = RS_SYSCALL;
> >  #ifndef CONFIG_USER_ONLY
> >      vm_stop(VMSTOP_DEBUG);
> > +    vm_status_set(VMST_DEBUG);
> >  #endif
> >      s->state = RS_IDLE;
> >      va_start(va, fmt);
> > @@ -2432,6 +2433,7 @@ static void gdb_read_byte(GDBState *s, int ch)
> >          /* when the CPU is running, we cannot do anything except stop
> >             it when receiving a char */
> >          vm_stop(VMSTOP_USER);
> > +        vm_status_set(VMST_DEBUG);
> >      } else
> >  #endif
> >      {
> > @@ -2694,6 +2696,7 @@ static void gdb_chr_event(void *opaque, int event)
> >      switch (event) {
> >      case CHR_EVENT_OPENED:
> >          vm_stop(VMSTOP_USER);
> > +        vm_status_set(VMST_DEBUG);
> >          gdb_has_xml = 0;
> >          break;
> >      default:
> 
> Previous hunk has VMST_DEBUG with VMST_DEBUG.  Odd.
> 
> > @@ -2735,6 +2738,7 @@ static void gdb_sigterm_handler(int signal)
> >  {
> >      if (vm_running) {
> >          vm_stop(VMSTOP_USER);
> > +        vm_status_set(VMST_DEBUG);
> >      }
> >  }
> >  #endif
> > diff --git a/hw/ide/core.c b/hw/ide/core.c
> > index ca17a43..bf9df41 100644
> > --- a/hw/ide/core.c
> > +++ b/hw/ide/core.c
> > @@ -523,6 +523,7 @@ static int ide_handle_rw_error(IDEState *s, int error, 
> > int op)
> >          s->bus->error_status = op;
> >          bdrv_mon_event(s->bs, BDRV_ACTION_STOP, is_read);
> >          vm_stop(VMSTOP_DISKFULL);
> > +        vm_status_set(VMST_IOERROR);
> >      } else {
> >          if (op & BM_STATUS_DMA_RETRY) {
> >              dma_buf_commit(s, 0);
> > diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
> > index a8c7372..66037fd 100644
> > --- a/hw/scsi-disk.c
> > +++ b/hw/scsi-disk.c
> > @@ -216,6 +216,7 @@ static int scsi_handle_rw_error(SCSIDiskReq *r, int 
> > error, int type)
> >  
> >          bdrv_mon_event(s->bs, BDRV_ACTION_STOP, is_read);
> >          vm_stop(VMSTOP_DISKFULL);
> > +        vm_status_set(VMST_IOERROR);
> >      } else {
> >          if (type == SCSI_REQ_STATUS_RETRY_READ) {
> >              scsi_req_data(&r->req, 0);
> > diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c
> > index 91e0394..bf70200 100644
> > --- a/hw/virtio-blk.c
> > +++ b/hw/virtio-blk.c
> > @@ -79,6 +79,7 @@ static int virtio_blk_handle_rw_error(VirtIOBlockReq 
> > *req, int error,
> >          s->rq = req;
> >          bdrv_mon_event(s->bs, BDRV_ACTION_STOP, is_read);
> >          vm_stop(VMSTOP_DISKFULL);
> > +        vm_status_set(VMST_IOERROR);
> >      } else {
> >          virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
> >          bdrv_mon_event(s->bs, BDRV_ACTION_REPORT, is_read);
> > diff --git a/hw/watchdog.c b/hw/watchdog.c
> > index 1c900a1..d130cbb 100644
> > --- a/hw/watchdog.c
> > +++ b/hw/watchdog.c
> > @@ -133,6 +133,7 @@ void watchdog_perform_action(void)
> >      case WDT_PAUSE:             /* same as 'stop' command in monitor */
> >          watchdog_mon_event("pause");
> >          vm_stop(VMSTOP_WATCHDOG);
> > +        vm_status_set(VMST_WATCHDOG);
> >          break;
> >  
> >      case WDT_DEBUG:
> > diff --git a/kvm-all.c b/kvm-all.c
> > index cbc2532..aee9e0a 100644
> > --- a/kvm-all.c
> > +++ b/kvm-all.c
> > @@ -1015,6 +1015,7 @@ int kvm_cpu_exec(CPUState *env)
> >      if (ret < 0) {
> >          cpu_dump_state(env, stderr, fprintf, CPU_DUMP_CODE);
> >          vm_stop(VMSTOP_PANIC);
> > +        vm_status_set(VMST_INTERROR);
> >      }
> >  
> >      env->exit_request = 0;
> > diff --git a/migration.c b/migration.c
> > index af3a1f2..674792f 100644
> > --- a/migration.c
> > +++ b/migration.c
> > @@ -394,6 +394,9 @@ void migrate_fd_put_ready(void *opaque)
> >              }
> >              state = MIG_STATE_ERROR;
> >          }
> > +        if (state == MIG_STATE_COMPLETED) {
> > +            vm_status_set(VMST_POSTMIGRATE);
> > +        }
> >          s->state = state;
> >          notifier_list_notify(&migration_state_notifiers);
> >      }
> > diff --git a/monitor.c b/monitor.c
> > index 67ceb46..1cb3191 100644
> > --- a/monitor.c
> > +++ b/monitor.c
> > @@ -1258,6 +1258,7 @@ static void do_singlestep(Monitor *mon, const QDict 
> > *qdict)
> >  static int do_stop(Monitor *mon, const QDict *qdict, QObject **ret_data)
> >  {
> >      vm_stop(VMSTOP_USER);
> > +    vm_status_set(VMST_PAUSED);
> >      return 0;
> >  }
> >  
> > @@ -2782,7 +2783,9 @@ static void do_loadvm(Monitor *mon, const QDict 
> > *qdict)
> >  
> >      vm_stop(VMSTOP_LOADVM);
> >  
> > -    if (load_vmstate(name) == 0 && saved_vm_running) {
> > +    if (load_vmstate(name) < 0) {
> > +        vm_status_set(VMST_LOADERROR);
> > +    } else if (saved_vm_running) {
> >          vm_start();
> >      }
> >  }
> > diff --git a/sysemu.h b/sysemu.h
> > index d3013f5..7308ac5 100644
> > --- a/sysemu.h
> > +++ b/sysemu.h
> > @@ -77,6 +77,25 @@ int qemu_savevm_state_complete(Monitor *mon, QEMUFile 
> > *f);
> >  void qemu_savevm_state_cancel(Monitor *mon, QEMUFile *f);
> >  int qemu_loadvm_state(QEMUFile *f);
> >  
> > +typedef enum {
> > +    VMST_NOSTATUS,
> > +    VMST_DEBUG,
> > +    VMST_INMIGRATE,
> > +    VMST_POSTMIGRATE,
> > +    VMST_INTERROR,
> > +    VMST_IOERROR,
> > +    VMST_LOADERROR,
> > +    VMST_PAUSED,
> > +    VMST_PRELAUNCH,
> > +    VMST_RUNNING,
> > +    VMST_SHUTDOWN,
> > +    VMST_WATCHDOG,
> > +    VMST_MAX,
> > +} VMStatus;
> 
> How are these related to the VMSTOP_*?
> 
> Why do we need a separate enumeration?
> 
> > +
> > +void vm_status_set(VMStatus s);
> > +const char *vm_status_get_name(void);
> > +
> >  /* SLIRP */
> >  void do_info_slirp(Monitor *mon);
> >  
> > diff --git a/vl.c b/vl.c
> > index fcd7395..fb7208f 100644
> > --- a/vl.c
> > +++ b/vl.c
> > @@ -309,6 +309,37 @@ static int default_driver_check(QemuOpts *opts, void 
> > *opaque)
> >  }
> >  
> >  /***********************************************************/
> > +/* VMStatus */
> > +
> > +static const char *const vm_status_name[VMST_MAX] = {
> > +    [VMST_DEBUG] = "debug",
> > +    [VMST_INMIGRATE] = "inmigrate",
> > +    [VMST_POSTMIGRATE] = "postmigrate",
> > +    [VMST_INTERROR] = "internal-error",
> > +    [VMST_IOERROR] = "io-error",
> > +    [VMST_LOADERROR] = "load-state-error",
> > +    [VMST_PAUSED] = "paused",
> > +    [VMST_PRELAUNCH] = "prelaunch",
> > +    [VMST_RUNNING] = "running",
> > +    [VMST_SHUTDOWN] = "shutdown",
> > +    [VMST_WATCHDOG] = "watchdog-error",
> > +};
> > +
> > +static VMStatus qemu_vm_status = VMST_NOSTATUS;
> > +
> > +void vm_status_set(VMStatus s)
> > +{
> > +    assert(s > VMST_NOSTATUS && s < VMST_MAX);
> > +    qemu_vm_status = s;
> > +}
> > +
> > +const char *vm_status_get_name(void)
> > +{
> > +    assert(qemu_vm_status > VMST_NOSTATUS && qemu_vm_status < VMST_MAX);
> > +    return vm_status_name[qemu_vm_status];
> > +}
> > +
> 
> Couldn't find a better place than the ol' vl.c rubbish dump  ;)
> 
> [...]
>