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From:   Dexuan Cui <decui@microsoft.com>
To:     "longli@linuxonhyperv.com" <longli@linuxonhyperv.com>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Leon Romanovsky <leon@kernel.org>,
        Ajay Sharma <sharmaajay@microsoft.com>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Wei Liu <wei.liu@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
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        Paolo Abeni <pabeni@redhat.com>
CC:     "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
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        Long Li <longli@microsoft.com>,
        "stable@vger.kernel.org" <stable@vger.kernel.org>
Subject: RE: [PATCH v2] net: mana: Batch ringing RX queue doorbell on
 receiving packets
Thread-Topic: [PATCH v2] net: mana: Batch ringing RX queue doorbell on
 receiving packets
Thread-Index: AQHZpSXIMoXo+dT7t0ST/0M/X/rooa+Xsx2w
Date:   Fri, 23 Jun 2023 03:00:05 +0000
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> From: longli@linuxonhyperv.com
> Sent: Thursday, June 22, 2023 9:23 AM
>  ...
>=20
> It's inefficient to ring the doorbell page every time a WQE is posted to
> the received queue.
>=20
> Move the code for ringing doorbell page to where after we have posted all
> WQEs to the receive queue during a callback from napi_poll().
>=20
> Tests showed no regression in network latency benchmarks.
>=20
> Cc: stable@vger.kernel.org
> Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network
> Adapter (MANA)")
> Signed-off-by: Long Li <longli@microsoft.com>

Reviewed-by: Dexuan Cui <decui@microsoft.com>