[PATCH] net/vmxnet3: add spinlocks to register command access

[Ferruh Yigit]

On 11/30/2021 7:31 AM, Yong Wang wrote:
> -----Original Message-----
> From:"sahithi.singam at oracle.com"  <sahithi.singam at oracle.com>
> Date: Monday, November 8, 2021 at 12:23 AM
> To: Yong Wang<yongwang at vmware.com>
> Cc:"dev at dpdk.org"  <dev at dpdk.org>, Sahithi Singam<sahithi.singam at oracle.com>
> Subject: [PATCH] net/vmxnet3: add spinlocks to register command access
> 
>      From: Sahithi Singam<sahithi.singam at oracle.com>
> 
>      At present, there are no spinlocks around register command access.
>      This resulted in a race condition when two threads running on
>      two different cores invoked link_update function at the same time
>      to get link status. Due to this race condition, one of the threads
>      reported false link status value.
> 
>      Signed-off-by: Sahithi Singam<sahithi.singam at oracle.com>
>      ---
> 
> Thanks Sahithi for the patch.  As we discussed offline, in DPDK, the expectation is that control level synchronization should be handled by the application.  In my knowledge, currently no PMD guarantee such synchronization at driver callback level.  It makes more sense to have the application manages the synchronization as most likely it needs to work with multiple PMDs and it's better to keep this behavior consistent across all PMDs (i.e, it does not make a lot of sense to support this behavior only in one particular PMD).

ack,
updating patch status as rejected.