Re: [PATCH] nvme-pci: Use non-operational power state instead of D3 on Suspend-to-Idle

[Kai-Heng Feng <kai.heng.feng@canonical.com>]

at 03:16, Keith Busch <kbusch@kernel.org> wrote:

> On Thu, May 09, 2019 at 02:59:55AM +0800, Kai-Heng Feng wrote:
>> +static int nvme_do_resume_from_idle(struct pci_dev *pdev)
>> +{
>> +	struct nvme_dev *ndev = pci_get_drvdata(pdev);
>> +	int result;
>> +
>> +	pdev->dev_flags &= ~PCI_DEV_FLAGS_NO_D3;
>> +	ndev->ctrl.suspend_to_idle = false;
>> +
>> +	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
>> +	if (result < 0)
>> +		goto out;
>> +
>> +	result = nvme_pci_configure_admin_queue(ndev);
>> +	if (result)
>> +		goto out;
>> +
>> +	result = nvme_alloc_admin_tags(ndev);
>> +	if (result)
>> +		goto out;
>> +
>> +	ndev->ctrl.max_hw_sectors = NVME_MAX_KB_SZ << 1;
>> +	ndev->ctrl.max_segments = NVME_MAX_SEGS;
>> +	mutex_unlock(&ndev->shutdown_lock);
>
> This lock was never locked.

Yea, will fix this.

>
> But I think these special suspend/resume routines are too similar to the
> existing ones, they should just incorporate this feature if we need to
> do this.

That’s my original direction, but this requires a new bool to  
nvme_dev_disable(), so it becomes
static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown, bool  
suspend_to_idle)

And it starts to get messy.

Kai-Heng