Re: [dpdk-users] Support for more RSS hash types in vmxnet3

[Yong Wang <yongwang@vmware.com>]

-----Original Message-----
From: Iain Barker <iain.barker@oracle.com> on behalf of Iain Barker <iain.barker@oracle.com>
Date: Monday, March 18, 2019 at 6:58 AM
To: Yong Wang <yongwang@vmware.com>, Ferruh Yigit <ferruh.yigit@intel.com>, Jay Miller <jay.miller@oracle.com>, "users@dpdk.org" <users@dpdk.org>
Subject: RE: [dpdk-users] Support for more RSS hash types in vmxnet3

    On 8/21/2018 6:57 PM, Jay Miller wrote:
    > It's clear that the vmxnet3 driver (even as of 18.08) supports just a 
    > subset of RSS hash types:
    > 
    > #define VMXNET3_RSS_OFFLOAD_ALL ( \
    >      ETH_RSS_IPV4 | \
    >      ETH_RSS_NONFRAG_IPV4_TCP | \
    >      ETH_RSS_IPV6 | \
    >      ETH_RSS_NONFRAG_IPV6_TCP)
    > 
    > Are there plans to add support for other hash types (like 
    > ETH_RSS_NONFRAG_IPV4_UDP), or is this an architectural limitation of 
    > vmxnet3?
    
    
    On August 22, 2018 at 2:55 AM, Ferruh Yigit wrote:
        
    > Hi Yong,
    >    
    > Can you please double check if the driver reports all supported hash functions
    > correctly.
    >    
    > On v18.08, the RSS hf request from application changed from best effort to
    > strict requirement, meaning if an application request a hash function but driver
    > doesn't report it as supported API will return an error, that is why it is
    > important for PMD to report supported hf properly.
    >    
    > Thanks,
    > ferruh
    
    
    On September 13, 2018 6:44 PM, Yong Wang wrote:
    
    > That's pretty much all the hash types supported by vmxnet3 by default up to version 3.  
    > With version 4, UDP RSS will be supported but it's only supported on certain version of ESX.  
    > Since v4 driver is not out yet, current VMXNET3_RSS_OFFLOAD_ALL should be good.
    
    
    
    Ferruh/Yong,
    
    I notice that ESXi 6.7 has been released for some months now with support for VMXNET3 version 4 including with RSS for UDP
    https://docs.vmware.com/en/vSphere/6.7/solutions/vSphere-6.7.2cd6d2a77980cc623caa6062f3c89362/GUID-C500585C0560D28B71180A40A4767C57.html
    
    I'm surprised this wasn't already present in DPDK 19.02 given how long 6.7 has been available already.
    
    Is it just a matter of changing the definition of VMXNET3_RSS_OFFLOAD_ALL  in the PMD to support this, or are other changes required?
    
    thanks.
    Iain

Iain,

We do plan to upstream the change to support the new RSS types in the near future.  Currently it's still under internal testing.

Thanks,
Yong