On 30.05.2018 15:08, Igor Mammedov wrote:
> On Thu, 17 May 2018 10:15:17 +0200
> David Hildenbrand <da...@redhat.com> wrote:
>
>> For multi stage hotplug handlers, we'll have to do some error handling
>> in some hotplug functions, so let's use a local error variable (except
>> for unplug requests).
> I'd split out introducing local error into separate patch
> so patch would do a single thing.
>
>> Also, add code to pass control to the final stage hotplug handler at the
>> parent bus.
> But I don't agree with generic
> "} else if (dev->parent_bus && dev->parent_bus->hotplug_handler) {"
> forwarding, it's done by 3/14 for generic case and in case of
> special device that needs bus handler called from machine one,
> I'd suggest to do forwarding explicitly for that device only
> like we do with acpi_dev.
I decided to do it that way because it is generic and results in nicer
recovery handling (e.g. in case pc_dimm plug fails, we can simply
rollback all (for now MemoryDevice) previous plug operations).
IMHO, the resulting code is easier to read.
>From this handling it is clear that
"if we reach the hotplug handler, and it is not some special device
plugged by the machine (CPU, PC_DIMM), pass it on to the actual hotplug
handler if any exists"
>
>
>> Signed-off-by: David Hildenbrand <da...@redhat.com>
>> ---
>> hw/i386/pc.c | 39 +++++++++++++++++++++++++++++++--------
>> 1 file changed, 31 insertions(+), 8 deletions(-)
>>
>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>> index d768930d02..510076e156 100644
>> --- a/hw/i386/pc.c
>> +++ b/hw/i386/pc.c
>> @@ -2007,19 +2007,32 @@ static void pc_cpu_pre_plug(HotplugHandler
>> *hotplug_dev,
>> static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
>> DeviceState *dev, Error **errp)
>> {
>> + Error *local_err = NULL;
>> +
>> + /* final stage hotplug handler */
>> if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
>> - pc_cpu_pre_plug(hotplug_dev, dev, errp);
>> + pc_cpu_pre_plug(hotplug_dev, dev, &local_err);
>> + } else if (dev->parent_bus && dev->parent_bus->hotplug_handler) {
>> + hotplug_handler_pre_plug(dev->parent_bus->hotplug_handler, dev,
>> + &local_err);
>> }
>> + error_propagate(errp, local_err);
>> }
>>
>> static void pc_machine_device_plug_cb(HotplugHandler *hotplug_dev,
>> DeviceState *dev, Error **errp)
>> {
>> + Error *local_err = NULL;
>> +
>> + /* final stage hotplug handler */
>> if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
>> - pc_dimm_plug(hotplug_dev, dev, errp);
>> + pc_dimm_plug(hotplug_dev, dev, &local_err);
>> } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
>> - pc_cpu_plug(hotplug_dev, dev, errp);
>> + pc_cpu_plug(hotplug_dev, dev, &local_err);
>> + } else if (dev->parent_bus && dev->parent_bus->hotplug_handler) {
>> + hotplug_handler_plug(dev->parent_bus->hotplug_handler, dev,
>> &local_err);
>> }
>> + error_propagate(errp, local_err);
>> }
>>
>> static void pc_machine_device_unplug_request_cb(HotplugHandler *hotplug_dev,
>> @@ -2029,7 +2042,10 @@ static void
>> pc_machine_device_unplug_request_cb(HotplugHandler *hotplug_dev,
>> pc_dimm_unplug_request(hotplug_dev, dev, errp);
>> } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
>> pc_cpu_unplug_request_cb(hotplug_dev, dev, errp);
>> - } else {
>> + } else if (dev->parent_bus && dev->parent_bus->hotplug_handler) {
>> + hotplug_handler_unplug_request(dev->parent_bus->hotplug_handler,
>> dev,
>> + errp);
>> + } else if (!dev->parent_bus) {
>> error_setg(errp, "acpi: device unplug request for not supported
>> device"
>> " type: %s", object_get_typename(OBJECT(dev)));
>> }
>> @@ -2038,14 +2054,21 @@ static void
>> pc_machine_device_unplug_request_cb(HotplugHandler *hotplug_dev,
>> static void pc_machine_device_unplug_cb(HotplugHandler *hotplug_dev,
>> DeviceState *dev, Error **errp)
>> {
>> + Error *local_err = NULL;
>> +
>> + /* final stage hotplug handler */
>> if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
>> - pc_dimm_unplug(hotplug_dev, dev, errp);
>> + pc_dimm_unplug(hotplug_dev, dev, &local_err);
>> } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
>> - pc_cpu_unplug_cb(hotplug_dev, dev, errp);
>> - } else {
>> - error_setg(errp, "acpi: device unplug for not supported device"
>> + pc_cpu_unplug_cb(hotplug_dev, dev, &local_err);
>> + } else if (dev->parent_bus && dev->parent_bus->hotplug_handler) {
>> + hotplug_handler_unplug(dev->parent_bus->hotplug_handler, dev,
>> + &local_err);
>> + } else if (!dev->parent_bus) {
>> + error_setg(&local_err, "acpi: device unplug for not supported
>> device"
>> " type: %s", object_get_typename(OBJECT(dev)));
>> }
>> + error_propagate(errp, local_err);
>> }
>>
>> static HotplugHandler *pc_get_hotpug_handler(MachineState *machine,
>
--
Thanks,
David / dhildenb
