Hi Ferruh, thanks for your message.
We developed a ethtool-dpdk which is secondary process based dpdk 17.08
version. Our device
support hotplug detach, but hotplug deatch is failed when we use
ethtool-dpdk.We found the
secondary process will change the shared memory when initializing.Secondary
process calls
"rte_eth_dev_pci_allocate" function and enters "rte_eth_copy_pci_info" function.
(rte_eth_dev_pci_generic_probe -> rte_eth_dev_pci_allocate ->
rte_eth_copy_pci_info)
Then it sets the value of struct "rte_eth_dev_data.dev_flags" to zero.In our
platform, this value
is equal to 0x0003.(RTE_ETH_DEV_DETACHABLE | RTE_ETH_DEV_INTR_LSC),but after
reset
the "dev_flags", the value changed to 0x0002.(RTE_ETH_DEV_DETACHABLE).So, our
device hotplug
detach is failed.I found the similar problem in other dpdk version, include
dpdk 19.11.Even though
the deivce hotplug detach is discarded,but i think the shared memory changed is
unexpected by primary
process.
Our driver is ixgbe, i think this problem has a little relationship with
driver, Secondary process
enters "rte_eth_copy_pci_info" by "rte_eth_dev_pci_allocate".And I agree your
opinion, the helper
function should simple on what it does.I have two ways to fix this problem, one
is add an if-statement
in "rte_eth_dev_pci_allocate" function to forbid secondary process enters
"rte_eth_copy_pci_info" function,
another way is add an if-statement in "rte_eth_copy_pci_info" function to
forbid secondary process change
shared memory.And First way need to ensure the "rte_eth_copy_pci_info" function
won't be called anywhere else.
I think the second way is simple and lower risk.
Please forgive me because my poor english....
发件人：Ferruh Yigit <ferruh.yi...@intel.com>
发送日期：2020-01-14 22:45:33
收件人：Fang TongHao
<fangtong...@sangfor.com.cn>,tho...@monjalon.net,arybche...@solarflare.com
抄送人：dev@dpdk.org,sta...@dpdk.org,jia....@intel.com,cunming.li...@intel.com,qi.z.zh...@intel.com,jungle845943...@outlook.com
主题：Re: [dpdk-dev] [PATCH v2] Fixes: ethdev: secondary process change shared
memory>On 1/13/2020 5:03 AM, Fang TongHao wrote:
>> Secondary process calls “rte_eth_dev_pci_allocate”
>> function and enters rte_eth_copy_pci_info function
>> when initializing.Then it sets the value of struct
>> "rte_eth_dev_data.dev_flags" to zero and reset it,
>> but this struct is shared by primary process and
>> secondary process.To fix this bug,by adding an
>> if-statement to forbid the secondaryprocess changing
>> the above-mentioned value.
>
>Hi Fang,
>
>Thanks for the fix, I agree with the problem statement, but not sure if this
>should be handled in the helper function or in the place where the function is
>called. Helper function is simple on what it does, do we need to put the
>primary
>process logic in it.
>
>Can you please give more details of the bug you have encounter, is it seen by a
>specific PMD?
>
>Thanks,
>ferruh
>
>>
>> Signed-off-by: Fang TongHao <fangtong...@sangfor.com.cn>
>> ---
>> lib/librte_ethdev/rte_ethdev_pci.h | 18 ++++++++++--------
>> 1 file changed, 10 insertions(+), 8 deletions(-)
>>
>> diff --git a/lib/librte_ethdev/rte_ethdev_pci.h
>> b/lib/librte_ethdev/rte_ethdev_pci.h
>> index ccdbb46ec..e7dae0545 100644
>> --- a/lib/librte_ethdev/rte_ethdev_pci.h
>> +++ b/lib/librte_ethdev/rte_ethdev_pci.h
>> @@ -60,14 +60,16 @@ rte_eth_copy_pci_info(struct rte_eth_dev *eth_dev,
>>
>> eth_dev->intr_handle = &pci_dev->intr_handle;
>>
>> - eth_dev->data->dev_flags = 0;
>> - if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_LSC)
>> - eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_LSC;
>> - if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_RMV)
>> - eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_RMV;
>> -
>> - eth_dev->data->kdrv = pci_dev->kdrv;
>> - eth_dev->data->numa_node = pci_dev->device.numa_node;
>> + if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
>> + eth_dev->data->dev_flags = 0;
>> + if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_LSC)
>> + eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_LSC;
>> + if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_RMV)
>> + eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_RMV;
>> +
>> + eth_dev->data->kdrv = pci_dev->kdrv;
>> + eth_dev->data->numa_node = pci_dev->device.numa_node;
>> + }
>> }
>>
>> static inline int
>>
>
