On Wed, May 20, 2020 at 10:10:47AM -0700, Dongli Zhang wrote:
> On 5/20/20 4:56 AM, Ming Lei wrote:
> > +static bool nvme_wait_freeze_and_check(struct nvme_dev *dev)
> > +{
> > + bool frozen;
> > +
> > + while (true) {
> > + frozen = nvme_frozen(&dev->ctrl);
> > + if (frozen)
> > + break;
> > + if (!dev->online_queues)
> > + break;
> > + msleep(5);
> > + }
> > +
> > + return frozen;
> > +}
> > +
> > static void nvme_reset_work(struct work_struct *work)
> > {
> > struct nvme_dev *dev =
> > container_of(work, struct nvme_dev, ctrl.reset_work);
> > bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
> > int result;
> > + bool reset_done = true;
> >
> > if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING)) {
> > result = -ENODEV;
> > @@ -2606,8 +2622,9 @@ static void nvme_reset_work(struct work_struct *work)
> > nvme_free_tagset(dev);
> > } else {
> > nvme_start_queues(&dev->ctrl);
> > - nvme_wait_freeze(&dev->ctrl);
> > - nvme_dev_add(dev);
> > + reset_done = nvme_wait_freeze_and_check(dev);
>
> Once we arrive at here, it indicates "dev->online_queues >= 2".
>
> 2601 if (dev->online_queues < 2) {
> 2602 dev_warn(dev->ctrl.device, "IO queues not created\n");
> 2603 nvme_kill_queues(&dev->ctrl);
> 2604 nvme_remove_namespaces(&dev->ctrl);
> 2605 nvme_free_tagset(dev);
> 2606 } else {
> 2607 nvme_start_queues(&dev->ctrl);
> 2608 nvme_wait_freeze(&dev->ctrl);
> 2609 nvme_dev_add(dev);
> 2610 nvme_unfreeze(&dev->ctrl);
> 2611 }
>
> Is there any reason to check "if (!dev->online_queues)" in
> nvme_wait_freeze_and_check()?
Looks correct to me. If the queues fail to freeze, that means a timeout
occured, and the nvme timeout handler tears down all online queues, so
this patch uses that for the criteria to break out of the loop.
