On 2018/5/23 10:54, Wei Hu (Xavier) wrote:
>
> On 2018/5/23 4:26, Jason Gunthorpe wrote:
>> On Fri, May 18, 2018 at 03:23:00PM +0800, Wei Hu (Xavier) wrote:
>>> On 2018/5/18 12:15, Jason Gunthorpe wrote:
>>>> On Fri, May 18, 2018 at 11:28:11AM +0800, Wei Hu (Xavier) wrote:
>>>>> On 2018/5/17 23:14, Jason Gunthorpe wrote:
>>>>>> On Thu, May 17, 2018 at 04:02:52PM +0800, Wei Hu (Xavier) wrote:
>>>>>>> diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
>>>>>>> index 86ef15f..e1c44a6 100644
>>>>>>> +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
>>>>>>> @@ -774,6 +774,9 @@ static int hns_roce_cmq_send(struct hns_roce_dev *hr_dev,
>>>>>>> int ret = 0;
>>>>>>> int ntc;
>>>>>>>
>>>>>>> + if (hr_dev->is_reset)
>>>>>>> + return 0;
>>>>>>> +
>>>>>>> spin_lock_bh(&csq->lock);
>>>>>>>
>>>>>>> if (num > hns_roce_cmq_space(csq)) {
>>>>>>> @@ -4790,6 +4793,7 @@ static int hns_roce_hw_v2_init_instance(struct hnae3_handle *handle)
>>>>>>> return 0;
>>>>>>>
>>>>>>> error_failed_get_cfg:
>>>>>>> + handle->priv = NULL;
>>>>>>> kfree(hr_dev->priv);
>>>>>>>
>>>>>>> error_failed_kzalloc:
>>>>>>> @@ -4803,14 +4807,70 @@ static void hns_roce_hw_v2_uninit_instance(struct hnae3_handle *handle,
>>>>>>> {
>>>>>>> struct hns_roce_dev *hr_dev = (struct hns_roce_dev *)handle->priv;
>>>>>>>
>>>>>>> + if (!hr_dev)
>>>>>>> + return;
>>>>>>> +
>>>>>>> hns_roce_exit(hr_dev);
>>>>>>> + handle->priv = NULL;
>>>>>>> kfree(hr_dev->priv);
>>>>>>> ib_dealloc_device(&hr_dev->ib_dev);
>>>>>>> }
>>>>>> Why are these hunks here? If init fails then uninit should not be
>>>>>> called, so why meddle with priv?
>>>>> In hns_roce_hw_v2_init_instance function, we evaluate handle->priv with
>>>>> hr_dev,
>>>>> We want clear the value in hns_roce_hw_v2_uninit_instance function.
>>>>> So we can ensure no problem in RoCE driver.
>>>> What problem could happen?
>>>>
>>>> I keep removing unnecessary sets to null and checks of null, so please
>>>> don't add them if they cannot happen.
>>>>
>>>> Eg uninit should never be called with a null priv, that is a serious
>>>> logic mis-design someplace if it happens.
>>>>
>>>> Jason
>>> NIC driver call the registered reset_notify() function to finish the
>>> part of RoCE reset process.
>>> In RoCE driver, when hnae3_reset_notify_type is HNAE3_UNINIT_CLIENT,
>>> we call hns_roce_hw_v2_uninit_instance(handle, false) to release the
>>> resources.
>>> when hnae3_reset_notify_type is HNAE3_INIT_CLIENT, we call
>>> hns_roce_hw_v2_init_instance.
>>> if hns_roce_hw_v2_init_instance failed, we should ensure no problem in
>>> the other callback
>>> function registered by RoCE driver.
>> Don't design things like this.
>>
>> init/uninit are paired - do not call something uninit if it can be
>> called after init fails, or better, arrange to prevent that so things
>> are sane.
>>
>> Jason
>>
>> .
> The current RoCE driver registered 3 callback function to NIC driver as
> belows:
> 1.init_instance/uninit_instance are paired.
> 2.In reset_notify function, RoCE dirver still call
> init_instance/uninit_instance function.
> but NIC driver does not perceive the behavior. We need to judge in RoCE
> driver.
>
> static const struct hnae3_client_ops hns_roce_hw_v2_ops = {
> .init_instance = hns_roce_hw_v2_init_instance,
> .uninit_instance = hns_roce_hw_v2_uninit_instance,
> .reset_notify = hns_roce_hw_v2_reset_notify,
> };
struct hnae3_handle is defined in NIC driver, and handle->priv is used
for RoCE driver,
NIC driver will not use this member handle->priv.
struct hnae3_handle {
struct hnae3_client *client;
struct pci_dev *pdev;
void *priv;
struct hnae3_ae_algo *ae_algo; /* the class who provides this handle */
u64 flags; /* Indicate the capabilities for this handle*/
unsigned long last_reset_time;
enum hnae3_reset_type reset_level;
union {
struct net_device *netdev; /* first member */
struct hnae3_knic_private_info kinfo;
struct hnae3_unic_private_info uinfo;
struct hnae3_roce_private_info rinfo;
};
u32 numa_node_mask; /* for multi-chip support */
};
> Wei Hu
>
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> .
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