Re: [PATCH v3 1/8] migration/savevm: Move more savevm handling into vmstate_save()

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* David Hildenbrand (david@redhat.com) wrote:
> Let's move more code into vmstate_save(), reducing code duplication and
> preparing for reuse of vmstate_save() in qemu_savevm_state_setup(). We
> have to move vmstate_save() to make the compiler happy.
> 
> We'll now also trace from qemu_save_device_state().

Mostly OK, but..

> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  migration/savevm.c | 79 ++++++++++++++++++++++------------------------

Doesn't this also need to upate trace-events?

Dave

>  1 file changed, 37 insertions(+), 42 deletions(-)
> 
> diff --git a/migration/savevm.c b/migration/savevm.c
> index a0cdb714f7..d8830297e4 100644
> --- a/migration/savevm.c
> +++ b/migration/savevm.c
> @@ -897,17 +897,6 @@ static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se,
>      }
>  }
>  
> -static int vmstate_save(QEMUFile *f, SaveStateEntry *se,
> -                        JSONWriter *vmdesc)
> -{
> -    trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)");
> -    if (!se->vmsd) {
> -        vmstate_save_old_style(f, se, vmdesc);
> -        return 0;
> -    }
> -    return vmstate_save_state(f, se->vmsd, se->opaque, vmdesc);
> -}
> -
>  /*
>   * Write the header for device section (QEMU_VM_SECTION START/END/PART/FULL)
>   */
> @@ -941,6 +930,43 @@ static void save_section_footer(QEMUFile *f, SaveStateEntry *se)
>      }
>  }
>  
> +static int vmstate_save(QEMUFile *f, SaveStateEntry *se, JSONWriter *vmdesc)
> +{
> +    int ret;
> +
> +    if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
> +        return 0;
> +    }
> +    if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) {
> +        trace_savevm_section_skip(se->idstr, se->section_id);
> +        return 0;
> +    }
> +
> +    trace_savevm_section_start(se->idstr, se->section_id);
> +    save_section_header(f, se, QEMU_VM_SECTION_FULL);
> +    if (vmdesc) {
> +        json_writer_start_object(vmdesc, NULL);
> +        json_writer_str(vmdesc, "name", se->idstr);
> +        json_writer_int64(vmdesc, "instance_id", se->instance_id);
> +    }
> +
> +    trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)");
> +    if (!se->vmsd) {
> +        vmstate_save_old_style(f, se, vmdesc);
> +    } else {
> +        ret = vmstate_save_state(f, se->vmsd, se->opaque, vmdesc);
> +        if (ret) {
> +            return ret;
> +        }
> +    }
> +
> +    trace_savevm_section_end(se->idstr, se->section_id, 0);
> +    save_section_footer(f, se);
> +    if (vmdesc) {
> +        json_writer_end_object(vmdesc);
> +    }
> +    return 0;
> +}
>  /**
>   * qemu_savevm_command_send: Send a 'QEMU_VM_COMMAND' type element with the
>   *                           command and associated data.
> @@ -1374,31 +1400,11 @@ int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f,
>      json_writer_int64(vmdesc, "page_size", qemu_target_page_size());
>      json_writer_start_array(vmdesc, "devices");
>      QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
> -
> -        if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
> -            continue;
> -        }
> -        if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) {
> -            trace_savevm_section_skip(se->idstr, se->section_id);
> -            continue;
> -        }
> -
> -        trace_savevm_section_start(se->idstr, se->section_id);
> -
> -        json_writer_start_object(vmdesc, NULL);
> -        json_writer_str(vmdesc, "name", se->idstr);
> -        json_writer_int64(vmdesc, "instance_id", se->instance_id);
> -
> -        save_section_header(f, se, QEMU_VM_SECTION_FULL);
>          ret = vmstate_save(f, se, vmdesc);
>          if (ret) {
>              qemu_file_set_error(f, ret);
>              return ret;
>          }
> -        trace_savevm_section_end(se->idstr, se->section_id, 0);
> -        save_section_footer(f, se);
> -
> -        json_writer_end_object(vmdesc);
>      }
>  
>      if (inactivate_disks) {
> @@ -1594,21 +1600,10 @@ int qemu_save_device_state(QEMUFile *f)
>          if (se->is_ram) {
>              continue;
>          }
> -        if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
> -            continue;
> -        }
> -        if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) {
> -            continue;
> -        }
> -
> -        save_section_header(f, se, QEMU_VM_SECTION_FULL);
> -
>          ret = vmstate_save(f, se, NULL);
>          if (ret) {
>              return ret;
>          }
> -
> -        save_section_footer(f, se);
>      }
>  
>      qemu_put_byte(f, QEMU_VM_EOF);
> -- 
> 2.39.0
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK