On Mon, May 08, 2023 at 02:45:44PM +0000, Haiyang Zhang wrote:

quoted

-----Original Message-----
From: Leon Romanovsky <leon@kernel.org>
Sent: Monday, May 8, 2023 2:10 AM
To: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Long Li <longli@microsoft.com>; Jason Gunthorpe <jgg@ziepe.ca>; Ajay
Sharma [off-list ref]; Dexuan Cui [off-list ref];
KY Srinivasan [off-list ref]; Wei Liu [off-list ref]; David S.
Miller [off-list ref]; Eric Dumazet [off-list ref];
Jakub Kicinski [off-list ref]; Paolo Abeni [off-list ref]; linux-
rdma@vger.kernel.org; linux-hyperv@vger.kernel.org;
netdev@vger.kernel.org; linux-kernel@vger.kernel.org
Subject: Re: [PATCH] RDMA/mana_ib: Use v2 version of cfg_rx_steer_req to
enable RX coalescing

On Sun, May 07, 2023 at 09:39:27PM +0000, Haiyang Zhang wrote:

quoted

quoted

-----Original Message-----
From: Leon Romanovsky <leon@kernel.org>
Sent: Sunday, May 7, 2023 4:11 AM
To: Long Li <longli@microsoft.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>; Ajay Sharma
[off-list ref]; Dexuan Cui [off-list ref]; KY
Srinivasan [off-list ref]; Haiyang Zhang

[off-list ref];

quoted

quoted

Wei Liu [off-list ref]; David S. Miller [off-list ref]; Eric
Dumazet [off-list ref]; Jakub Kicinski [off-list ref];

Paolo

quoted

quoted

Abeni [off-list ref]; linux-rdma@vger.kernel.org; linux-
hyperv@vger.kernel.org; netdev@vger.kernel.org; linux-
kernel@vger.kernel.org
Subject: Re: [PATCH] RDMA/mana_ib: Use v2 version of cfg_rx_steer_req

to

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quoted

enable RX coalescing

On Fri, May 05, 2023 at 11:51:48AM -0700, longli@linuxonhyperv.com
wrote:

quoted

From: Long Li <longli@microsoft.com>

With RX coalescing, one CQE entry can be used to indicate multiple

packets

quoted

quoted

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on the receive queue. This saves processing time and PCI bandwidth over
the CQ.

Signed-off-by: Long Li <longli@microsoft.com>
---
 drivers/infiniband/hw/mana/qp.c |  5 ++++-
 include/net/mana/mana.h         | 17 +++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

Why didn't you change mana_cfg_vport_steering() too?

The mana_cfg_vport_steering() is for mana_en (Enthernet) driver, not the
mana_ib driver.

The changes for mana_en will be done in a separate patch together with
changes for mana_en RX code patch to support multiple packets / CQE.

I'm aware of the difference between mana_en and mana_ib.

The change you proposed doesn't depend on "support multiple packets /
CQE."
and works perfectly with one packet/CQE also, does it?

No.
If we add the following setting to the mana_en / mana_cfg_vport_steering(),
the NIC may put multiple packets in one CQE, so we need to have the changes
for mana_en RX code path to support multiple packets / CQE.
+	req->cqe_coalescing_enable = true;

You can leave "cqe_coalescing_enable = false" for ETH and still reuse
your new v2 struct.

H> 

So we plan to set this cqe_coalescing_enable, and the changes for mana_en 
RX code path to support multiple packets / CQE in another patch.

And how does it work with IB without changing anything except this
proposed patch?

Thanks

Thanks,
- Haiyang